@article{park_lu_park_rozgonyi_2015, title={Impact of structural defect density on gettering of transition metal impurities during phosphorus emitter diffusion in multi-crystalline silicon solar cell processing}, volume={11}, number={4}, journal={Electronic Materials Letters}, author={Park, Y. and Lu, J. and Park, J. H. and Rozgonyi, G.}, year={2015}, pages={658–663} } @article{park_lu_park_rozgonyi_2015, title={The influence of hydrogenation on the electrical properties of impurity-contaminated silicon grain boundaries}, volume={11}, number={6}, journal={Electronic Materials Letters}, author={Park, Y. and Lu, J. G. and Park, J. H. and Rozgonyi, G.}, year={2015}, pages={993–997} } @article{leonard_markevich_peaker_hamilton_yousseff_rozgonyi_2014, title={Molybdenum nano-precipitates in silicon: A TEM and DLTS study}, volume={251}, number={11}, journal={Physica Status Solidi. B, Basic Solid State Physics}, author={Leonard, S. and Markevich, V. P. and Peaker, A. R. and Hamilton, B. and Yousseff, K. and Rozgonyi, G.}, year={2014}, pages={2201–2204} } @article{bharathan_zhou_narayan_rozgonyi_bulman_2014, title={Thermal Misfit Strain Relaxation in Ge/(001)Si Heterostructures}, volume={43}, ISSN={["1543-186X"]}, DOI={10.1007/s11664-014-3247-6}, number={9}, journal={JOURNAL OF ELECTRONIC MATERIALS}, author={Bharathan, Jayesh and Zhou, Honghui and Narayan, Jagdish and Rozgonyi, George and Bulman, Gary E.}, year={2014}, month={Sep}, pages={3196–3203} } @article{bharathan_narayan_rozgonyi_bulman_2013, title={Defect Characterization in Ge/(001)Si Epitaxial Films Grown by Reduced-Pressure Chemical Vapor Deposition}, volume={42}, ISSN={["1543-186X"]}, DOI={10.1007/s11664-013-2686-9}, number={10}, journal={JOURNAL OF ELECTRONIC MATERIALS}, author={Bharathan, Jayesh and Narayan, Jagdish and Rozgonyi, George and Bulman, Gary E.}, year={2013}, month={Oct}, pages={2888–2896} } @article{youssef_shi_radue_good_rozgonyi_2013, title={Effect of oxygen and associated residual stresses on the mechanical properties of high growth rate Czochralski silicon}, volume={113}, number={13}, journal={Journal of Applied Physics}, author={Youssef, K. and Shi, M. and Radue, C. and Good, E. and Rozgonyi, G.}, year={2013} } @article{shi_youssef_rozgonyi_2013, title={Fracture strength of photovoltaic silicon wafers evaluated using a controlled flaw method}, volume={15}, number={8}, journal={Advanced Engineering Materials}, author={Shi, M. R. and Youssef, K. and Rozgonyi, G. A.}, year={2013}, pages={756–760} } @article{jiang_yu_gu_rozgonyi_yang_2013, title={Modulation of electrical characteristics at a Ni-contaminated silicon grain boundary by engineering the metal precipitates}, volume={210}, number={9}, journal={Physica Status Solidi. A, Applications and Materials Science}, author={Jiang, T. T. and Yu, X. G. and Gu, X. and Rozgonyi, G. and Yang, D. R.}, year={2013}, pages={1828–1831} } @article{yoon_yan_ostrom_kim_rozgonyi_2012, title={Deep level transient spectroscopy and minority carrier lifetime study on Ga-doped continuous Czochralski silicon}, volume={101}, number={22}, journal={Applied Physics Letters}, author={Yoon, Y. and Yan, Y. X. and Ostrom, N. P. and Kim, J. and Rozgonyi, G.}, year={2012} } @article{yoon_paudyal_kim_ok_kulshreshtha_johnston_rozgonyi_2012, title={Effect of nickel contamination on high carrier lifetime n-type crystalline silicon}, volume={111}, number={3}, journal={Journal of Applied Physics}, author={Yoon, Y. and Paudyal, B. and Kim, J. and Ok, Y. W. and Kulshreshtha, P. and Johnston, S. and Rozgonyi, G.}, year={2012} } @article{yoon_paudyal_kim_ok_kulshreshtha_johnston_rozgonyi_2012, title={Effect of nickel contamination on high carrier lifetime n-type crystalline silicon (vol 111, 033702, 2012)}, volume={111}, number={4}, journal={Journal of Applied Physics}, author={Yoon, Y. and Paudyal, B. and Kim, J. and Ok, Y. W. and Kulshreshtha, P. and Johnston, S. and Rozgonyi, G.}, year={2012} } @article{kulshreshtha_youssef_rozgonyi_2012, title={Nano-indentation: A tool to investigate crack propagation related phase transitions in PV silicon}, volume={96}, number={1}, journal={Solar Energy Materials and Solar Cells}, author={Kulshreshtha, P. K. and Youssef, K. M. and Rozgonyi, G.}, year={2012}, pages={166–172} } @article{kulshreshtha_yoon_youssef_good_rozgonyi_2012, title={Oxygen precipitation related stress-modified crack propagation in high growth rate Czochralski silicon wafers}, volume={159}, number={2}, journal={Journal of the Electrochemical Society}, author={Kulshreshtha, P. K. and Yoon, Y. and Youssef, K. M. and Good, E. A. and Rozgonyi, G.}, year={2012}, pages={H125–129} } @article{bharathan_narayan_rozgonyi_bulman_2013, title={Poisson Ratio of Epitaxial Germanium Films Grown on Silicon}, volume={42}, ISSN={["0361-5235"]}, DOI={10.1007/s11664-012-2337-6}, abstractNote={An accurate knowledge of elastic constants of thin films is important in understanding the effect of strain on material properties. We have used residual thermal strain to measure the Poisson ratio of Ge films grown on Si ⟨001⟩ substrates, using the sin2 ψ method and high-resolution x-ray diffraction. The Poisson ratio of the Ge films was measured to be 0.25, compared with the bulk value of 0.27. Our study indicates that use of Poisson ratio instead of bulk compliance values yields a more accurate description of the state of in-plane strain present in the film.}, number={1}, journal={JOURNAL OF ELECTRONIC MATERIALS}, author={Bharathan, Jayesh and Narayan, Jagdish and Rozgonyi, George and Bulman, Gary E.}, year={2013}, month={Jan}, pages={40–46} } @article{youssef_yu_seacrist_rozgonyi_2012, title={Understanding the effect of impurities and grain boundaries on mechanical behavior of Si via nanoindentation of (110)/(100) direct Si bonded wafers}, volume={27}, number={1}, journal={Journal of Materials Research}, author={Youssef, K. and Yu, X. G. and Seacrist, M. and Rozgonyi, G.}, year={2012}, pages={349–355} } @article{yu_li_fan_yang_kittler_reiche_seibt_rozgonyi_2010, title={Effect of Au contamination on the electrical characteristics of a "model" small-angle grain boundary in n-type direct silicon bonded wafer}, volume={108}, number={5}, journal={Journal of Applied Physics}, author={Yu, X. and Li, X. and Fan, R. and Yang, D. and Kittler, M. and Reiche, M. and Seibt, M. and Rozgonyi, G.}, year={2010} } @article{li_yu_song_yang_rozgonyi_2010, title={Effect of nickel contamination on grain boundary states at a direct silicon bonded (110)/(100) interface}, volume={63}, number={11}, journal={Scripta Materialia}, author={Li, X. Q. and Yu, X. G. and Song, L. H. and Yang, D. R. and Rozgonyi, G.}, year={2010}, pages={1100–1103} } @article{yoon_yi_yim_lee_rozgonyi_joo_2010, title={Microstructure and electrical properties of high power laser thermal annealing on inkjet-printed Ag films}, volume={87}, number={11}, journal={Microelectronic Engineering}, author={Yoon, Y. H. and Yi, S. M. and Yim, J. R. and Lee, J. H. and Rozgonyi, G. and Joo, Y. C.}, year={2010}, pages={2230–2233} } @article{yu_song_yang_kittler_rozgonyi_2010, title={Modulation of 1.5 mu m dislocation-related luminescence emitted from a direct silicon bonded interface by external bias}, volume={96}, number={21}, journal={Applied Physics Letters}, author={Yu, X. G. and Song, L. H. and Yang, D. R. and Kittler, M. and Rozgonyi, G. A.}, year={2010} } @article{park_lu_rozgonyi_2010, title={Segregation and thermal dissociation of hydrogen at the (110)/(001) silicon grain boundary}, volume={6}, number={1}, journal={Electronic Materials Letters}, author={Park, Y. and Lu, J. G. and Rozgonyi, G.}, year={2010}, pages={1–5} } @article{park_lu_rozgonyi_2009, title={Hydrogen passivation of deep energy levels at the interfacial grain boundary in (110)/(100) bonded silicon wafers}, volume={105}, number={1}, journal={Journal of Applied Physics}, author={Park, Y. and Lu, J. and Rozgonyi, G.}, year={2009} } @article{lu_yu_park_rozgonyi_2009, title={Investigation of iron impurity gettering at dislocations in a SiGe/Si heterostructure}, volume={105}, number={7}, journal={Journal of Applied Physics}, author={Lu, J. G. and Yu, X. G. and Park, Y. and Rozgonyi, G.}, year={2009} } @article{yu_lu_youssef_rozgonyi_2009, title={Proximity gettering of Cu at a (110)/(001) grain boundary interface formed by direct silicon bonding}, volume={94}, number={22}, journal={Applied Physics Letters}, author={Yu, X. and Lu, J. and Youssef, K. and Rozgonyi, G.}, year={2009} } @article{yu_lu_rozgonyi_2008, title={Capacitance transient and current-/capacitance-voltage study of direct silicon bonded (110)/(100) interface}, volume={92}, number={26}, journal={Applied Physics Letters}, author={Yu, X. G. and Lu, J. G. and Rozgonyi, G.}, year={2008} } @article{lu_rozgonyi_2008, title={Capacitance transient study of the influence of iron contamination on the electrical characteristics of silicon grain boundaries}, volume={92}, number={8}, journal={Applied Physics Letters}, author={Lu, J. G. and Rozgonyi, G.}, year={2008} } @article{lu_rozgonyi_schonecker_2008, title={Carrier lifetime limitation defects in polycrystalline silicon ribbons grown on substrate (RGS)}, volume={11}, ISSN={["1873-4081"]}, DOI={10.1016/j.mssp.2008.07.001}, abstractNote={Carrier lifetime limitation defects in polycrystalline silicon ribbons have been examined in samples with high oxygen and carbon content. Infrared spectroscopy showed that essentially all supersaturated oxygen impurities precipitated within 1 h annealing at over 800 °C. Preferential defect etching revealed that a much higher density of oxygen precipitates were generated in dislocation-free grains than in those highly dislocated (105–107 cm−2) ones. Correlated with electron-beam-induced current imaging, we found that oxygen precipitates are the dominant carrier recombination defects in dislocation-free grains, while dislocations are the lifetime killer for highly dislocated grains. It is suggested that eliminating dislocations alone will not improve the carrier lifetime, considering that a higher density of oxygen precipitates formed in the absence of dislocation-related heterogeneous nucleation sites will significantly degrade the carrier lifetime.}, number={1}, journal={MATERIALS SCIENCE IN SEMICONDUCTOR PROCESSING}, author={Lu, Jinggang and Rozgonyi, George A. and Schonecker, Axel}, year={2008}, month={Feb}, pages={20–24} } @article{lu_park_rozgonyi_2008, title={Deep level transient spectroscopy and capacitance-voltage study of dislocations and associated defects in SiGe/Si heterostructures}, volume={103}, number={7}, journal={Journal of Applied Physics}, author={Lu, J. G. and Park, Y. K. and Rozgonyi, G. A.}, year={2008} } @article{yu_lu_rozgonyi_2008, title={Deep-level transient spectroscopy study on direct silicon bonded (110)/(100) interfacial grain boundary}, volume={23}, number={12}, journal={Semiconductor Science and Technology}, author={Yu, X. G. and Lu, J. G. and Rozgonyi, G.}, year={2008} } @article{lu_rozgonyi_seacrist_chaumont_campion_2008, title={Effect of strained-Si layer thickness on dislocation distribution and SiGe relaxation in strained-Si/SiGe heterostructures}, volume={104}, number={7}, journal={Journal of Applied Physics}, author={Lu, J. G. and Rozgonyi, G. and Seacrist, M. and Chaumont, M. and Campion, A.}, year={2008} } @article{yu_lu_rozgonyi_2008, title={Impact of Cu contamination on the electrical properties of a direct silicon bonded (110)/(100) interfacial grain boundary}, volume={104}, number={11}, journal={Journal of Applied Physics}, author={Yu, X. G. and Lu, J. G. and Rozgonyi, G.}, year={2008} } @article{zhang_rozgonyi_yakimov_yarykin_seacrist_2008, title={Impact of thermal annealing on deep-level defects in strained-Si/SiGe heterostructure}, volume={103}, number={10}, journal={Journal of Applied Physics}, author={Zhang, R. H. and Rozgonyi, G. A. and Yakimov, E. and Yarykin, N. and Seacrist, M.}, year={2008} } @article{lu_rozgonyi_2007, title={Carrier capture cross sections of deep gap states at the interfacial grain boundary in a (110)/(100) bonded silicon wafer}, volume={91}, number={17}, journal={Applied Physics Letters}, author={Lu, J. and Rozgonyi, G.}, year={2007} } @article{wagener_zhang_rozgonyi_seacrist_ries_2007, title={Current transport characteristics across shallow hybrid-orientation silicon bonded interfaces}, volume={90}, number={11}, journal={Applied Physics Letters}, author={Wagener, M. C. and Zhang, R. H. and Rozgonyi, G. A. and Seacrist, M. and Ries, M.}, year={2007} } @article{yakimov_zhang_rozgonyi_seacrist_2007, title={EBIC characterization of strained Si/SiGe heterostructures}, volume={41}, number={4}, journal={Semiconductors and Semimetals}, author={Yakimov, E. B. and Zhang, R. H. and Rozgonyi, G. A. and Seacrist, M.}, year={2007}, pages={402–406} } @article{wagener_seacrist_rozgonyi_2007, title={Passivation of hybrid-orientation direct silicon bonded interfaces}, volume={401}, ISSN={["1873-2135"]}, DOI={10.1016/j.physb.2007.09.022}, abstractNote={This paper reports on the effect hydrogenation has on the electrical properties of hybrid-orientation (1 1 0)/(1 0 0) direct silicon bonded interfaces. Temperature-dependent capacitance measurements and deep-level transient spectroscopy were used to evaluate the distribution of interface states following hydrogenation. Although the overall interface charge remained nearly unchanged, the interface state distribution was significantly altered, changing from a broad band of states to a narrow energy distribution positioned near mid-gap.}, journal={PHYSICA B-CONDENSED MATTER}, author={Wagener, Magnus C. and Seacrist, Mike and Rozgonyi, George A.}, year={2007}, month={Dec}, pages={564–567} } @article{zhao_duscher_rozgonyi_zikry_chopra_ozturk_2007, title={Quantitative nanoscale local strain profiling in embedded SiGe metal-oxide-semiconductor structures}, volume={90}, ISSN={["1077-3118"]}, url={http://www.scopus.com/inward/record.url?eid=2-s2.0-34248361149&partnerID=MN8TOARS}, DOI={10.1063/1.2738188}, abstractNote={Mechanical strain by strain engineering has been widely used in Si metal-oxide-semiconductor field effect transistors. Experimental convergent beam electron diffraction (CBED) strain measurements and finite element calculations to quantitatively correlate the strain in the transmission electron microscope (TEM) sample with the actual device. It was found that the magnitude of the longitudinal strain, εx, along the channel direction, is about 20% higher in the TEM sample than in the real device. This combined approach can be used to explain data from other CBED studies of strained Si devices.}, number={19}, journal={APPLIED PHYSICS LETTERS}, author={Zhao, W. and Duscher, G. and Rozgonyi, G. and Zikry, M. A. and Chopra, S. and Ozturk, M. C.}, year={2007}, month={May} } @article{lu_rozgonyi_2006, title={Oxygen and carbon precipitation in crystalline sheet silicon - Depth profiling by infrared spectroscopy, and preferential defect etching}, volume={153}, ISSN={["1945-7111"]}, DOI={10.1149/1.2347103}, abstractNote={The depth variation of oxygen and carbon precipitation in multicrystalline sheet silicon has been examined by infrared microspectroscopy, electron-beam induced current (EBIC), and preferential defect etching. Experimental results on the depth profiles of interstitial oxygen (O i ), substitutional carbon (C s ), and oxygen precipitates, plus numerical analyses of vacancy-interstitial distribution indicate that oxygen precipitation is controlled by the initial O i concentration and quenched-in vacancies. In addition, it is found that the C s depth profile in the annealed samples mimics the O i profile. Examination of the precipitate density and the C s reduction rate allows us to show that formation of interstitial carbon by capturing self-interstitials generated during oxygen precipitation is a necessary step in explaining the fast C s reduction. From the fact that the carbon precipitation rate is controlled not only by the self-interstitial generation, but also by the precipitate density, it is suggested that the generated interstitial carbon impurities are most likely to coprecipitate at common sites with O i .}, number={11}, journal={JOURNAL OF THE ELECTROCHEMICAL SOCIETY}, author={Lu, Jinggang and Rozgonyi, George}, year={2006}, pages={G986–G991} } @article{stoddard_duscher_windl_rozgonyi_2005, title={A new understanding of near-threshold damage for 200 keV irradiation in silicon}, volume={40}, ISSN={["1573-4803"]}, DOI={10.1007/s10853-005-1059-z}, number={14}, journal={JOURNAL OF MATERIALS SCIENCE}, author={Stoddard, N and Duscher, G and Windl, W and Rozgonyi, G}, year={2005}, month={Jul}, pages={3639–3650} } @inproceedings{lu_rozgonyi_rand_jonczyk_2005, title={EBIC study of electrical activity of stacking faults in multicrystalline sheet silicon}, volume={108-109}, ISBN={3908450640}, booktitle={Proceedings of the 9th International Autumn Meeting: Gettering and defect engineering in semiconductor technology: GADEST 2001, S. Tecla, Italy, September 30-October 3, 2001 (Solid state phenomena)}, publisher={Uetikon-Zurich, Switzerland: Sci-Tech Pub. Ltd.; Enfield, N.H.: Trans Tech Pub. Ltd.}, author={Lu, J. G. and Rozgonyi, G. and Rand, J. and Jonczyk, R.}, year={2005}, pages={627–630} } @article{bray_zhao_kordas_wise_robinson_rozgonyi_2005, title={Electrical, structural, and chemical analysis of defects in epitaxial SiGe-based heterostructures}, volume={152}, number={5}, journal={Journal of the Electrochemical Society}, author={Bray, K. R. and Zhao, W. and Kordas, L. and Wise, R. and Robinson, M. and Rozgonyi, G.}, year={2005}, pages={C310–315} } @article{lu_rozgonyi_schonecker_gutjahr_liu_2005, title={Impact of oxygen on carbon precipitation in polycrystalline ribbon silicon}, volume={97}, number={3}, journal={Journal of Applied Physics}, author={Lu, J. G. and Rozgonyi, G. and Schonecker, A. and Gutjahr, A. and Liu, Z. X.}, year={2005} } @article{stoddard_duscher_karoui_stevie_rozgonyi_2005, title={Segregation and enhanced diffusion of nitrogen in silicon induced by low energy ion bombardment}, volume={97}, ISSN={["1089-7550"]}, DOI={10.1063/1.1866480}, abstractNote={A sample of nitrogen-doped, single crystal Czochralski silicon was subjected to several different surface preparations. Secondary ion mass spectrometry depth profiling has shown that prolonged glancing-angle bombardment by 3–5kV Ar+ ions significantly increases the nitrogen concentration in the near surface by up to an order of magnitude over the bulk value. Concentrations are observed to be elevated over the bulk value to a depth up to 25μm. Nitrogen-implanted samples and samples with a 1nm surface nitride did not exhibit nitrogen segregation under the same conditions, but a sample with 100nm of surface nitride did exhibit ion bombardment induced drive-in. In nitride-free samples, the source of the nitrogen is indicated to be a nitrogen-rich layer in the first micron of material. The diffusion behavior of nitrogen in silicon is discussed and the Crowdion mechanism for diffusion is suggested as the enabling mechanism for the enhanced low temperature diffusion.}, number={8}, journal={JOURNAL OF APPLIED PHYSICS}, author={Stoddard, N and Duscher, G and Karoui, A and Stevie, F and Rozgonyi, G}, year={2005}, month={Apr} } @article{kvit_karoui_duscher_rozgonyi_2004, title={"Umbrella"-like precipitates in nitrogen-doped Czochralski silicon wafers}, volume={84}, ISSN={["1077-3118"]}, DOI={10.1063/1.1669069}, abstractNote={Nitrogen effect on nucleation of oxygen precipitates in Czochralski Si has been investigated by transmission electron microscopy, Z-contrast imaging, and electron energy loss spectrometry (EELS). We have examined unusual “umbrella” shape oxygen precipitates in bulk of ingot in depths of more than 40 μm. Two predominant orientations of “umbrella” have been found along [110] and [−1−10] directions. We have investigated the distribution of nitrogen, oxygen, and interstitial Si by EELS profile taken simultaneously with HR Z-contrast image. The mechanism of nitrogen-enriched oxygen precipitates nucleation has been discussed.}, number={11}, journal={APPLIED PHYSICS LETTERS}, author={Kvit, A and Karoui, A and Duscher, G and Rozgonyi, GA}, year={2004}, month={Mar}, pages={1889–1891} } @article{rozgonyi_lu_zhang_rand_jonczyk_2004, title={Evaluation of silicon sheet film growth and wafer processing via structural, chemical and electrical diagnostics}, volume={95-96}, journal={Diffusion and Defect Data. [Pt. B], Solid State Phenomena}, author={Rozgonyi, G. A. and Lu, J. and Zhang, R. and Rand, J. and Jonczyk, R.}, year={2004}, pages={211–216} } @article{zhang_dyk_rozgonyi_rand_jonczyk_2004, title={Investigation of foreign particles in polycrystalline silicon using infrared microscopy}, volume={82}, ISSN={["0927-0248"]}, DOI={10.1016/j.solmat.2003.11.031}, abstractNote={The presence of SiC and SiNO particles in as-grown polycrystalline silicon has been investigated using infrared (IR) microscopy. These foreign particles were also characterized using electron beam induced current measurements, and scanning electron microscopy together with energy dispersive spectrum analyses. These performance-degrading inclusions were found to be distributed throughout the bulk of the material and varied in size from several microns to about 20 μm. In addition to the observation of the foreign particles, the feasibility of using IR microscopy as a characterization tool was also demonstrated.}, number={4}, journal={SOLAR ENERGY MATERIALS AND SOLAR CELLS}, author={Zhang, R and Dyk, EE and Rozgonyi, GA and Rand, J and Jonczyk, R}, year={2004}, month={May}, pages={577–585} } @article{lu_rozgonyi_rand_jonczyk_2004, title={Oxygen precipitate denuded zone in polycrystalline sheet silicon}, volume={85}, ISSN={["1077-3118"]}, DOI={10.1063/1.1781369}, abstractNote={The spatial variation of oxygen precipitation across the thickness of polycrystalline sheet silicon has been investigated by Fourier transform infrared (FTIR) microspectroscopy and preferential etching/optical microscopy. FTIR shows that interstitial oxygen is depleted near the top surface of the as-grown sample, thereby suppressing oxygen precipitation during subsequent annealing. Preferential etching and electron-beam-induced current imaging of polished cross sections revealed a 250-μm-wide precipitate denuded zone near the top surface. Evidently, growth-induced near-surface reduction of the oxygen profile keeps the oxygen supersaturation below a critical level for precipitate nucleation. Considering that the minority carrier diffusion length of current finished sheet silicon solar cells ranges from 50to100μm, it is anticipated that optimization of the 250-μm-wide precipitate denuded zone will improve solar cell performance.}, number={7}, journal={APPLIED PHYSICS LETTERS}, author={Lu, JG and Rozgonyi, G and Rand, J and Jonczyk, R}, year={2004}, month={Aug}, pages={1178–1180} } @article{karoui_karoui_rozgonyi_yang_2004, title={Oxygen precipitation in nitrogen doped Czochralski silicon wafers. I. Formation mechanisms of near-surface and bulk defects}, volume={96}, ISSN={["1089-7550"]}, DOI={10.1063/1.1773921}, abstractNote={Defect size distributions in nitrogen-doped Czochralski (N-CZ) silicon wafers were obtained using an oxygen precipitate profiler and Wright-Jenkins etching. These showed unique depth dependence in low-high and high-low-high cycled N-CZ wafers. Unique phenomena observed include a high defect concentration at the subsurface that decreases within the top 2μm of the so-called denuded zone. In contrast to N-free CZ Si for which the first high step annealing dissolves the grown-in defects, these appeared to be stable in N-CZ Si. As a result, the defect size distribution in the bulk was found to be independent of the annealing cycle. It was also found that the depth dependent defect concentration correlates well with oxygen and strongly with nitrogen secondary ion mass spectroscopy profiles, suggesting that nitrogen is the leading impurity in the defect formation processes even though introduced at very low concentration. Nitrogen appeared to effectively modify the nucleation regime by a drastic increase of the nuclei density. At low temperature under external stress, nitrogen and oxygen cosegregate to the surface where the stress is applied; such a phenomenon is largely increased at high temperature.}, number={6}, journal={JOURNAL OF APPLIED PHYSICS}, author={Karoui, A and Karoui, FS and Rozgonyi, GA and Yang, D}, year={2004}, month={Sep}, pages={3255–3263} } @article{karoui_rozgonyi_2004, title={Oxygen precipitation in nitrogen doped Czochralski silicon wafers. II. Effects of nitrogen and oxygen coupling}, volume={96}, ISSN={["1089-7550"]}, DOI={10.1063/1.1773922}, abstractNote={Nitrogen segregation and coprecipitation with oxygen in N-doped Czochralski (N-CZ) silicon wafers are investigated as a function of depth based on extended defect structure and chemical composition. High resolution nitrogen and oxygen secondary ion mass spectroscopy imaging revealed strong coupling of oxygen with nitrogen in annealed as well as in “as-grown” N-CZ Si wafers. In both cases, the near-surface regions appeared highly supersaturated in N and O forming a continuum of defects initiated by N-O complexes. The N and O stoichiometry depth profiles were found to depend on the material thermal history. The spatial variation of the stoichiometry ratio was also determined for precipitates using a combination of scanning transmission electron microscope (STEM) in Z-contrast mode with electron energy loss spectroscopy. The precipitate atomic and microstructures, analyzed by high resolution TEM and STEM, clearly demonstrate that second phase precipitate is precursor to a third phase that is an outer oxynitride shell. Nitrogen and oxygen cosegregation from the matrix to the precipitate interface occurs in a similar fashion as in the subsurface region. We propose a mechanism for oxygen precipitation in N-CZ Si based on N segregation to the interface while oxygen is trapped inside the oxynitride shell.}, number={6}, journal={JOURNAL OF APPLIED PHYSICS}, author={Karoui, A and Rozgonyi, GA}, year={2004}, month={Sep}, pages={3264–3271} } @article{lu_rozgonyi_rand_jonczyk_2004, title={Secondary phase inclusions in polycrystalline sheet silicon}, volume={269}, ISSN={["1873-5002"]}, DOI={10.1016/j.jcrysgro.2004.05.022}, abstractNote={Secondary phase inclusions with a size of typically 1–3 μm were observed in polycrystalline sheet silicon samples by preferential etching/Normaski microscopy. The chemical compositions of these inclusions were characterized by secondary ion mass spectroscopy (SIMS) depth profile measurements. It was found that there are mainly two types of inclusions in the sheet Si: nitrogen-rich with trace oxygen, and carbon-rich with trace nitrogen. Fourier transform infrared (FTIR) spectroscopy results indicated that the nitrogen rich particles are either α-Si3N4 or silicon oxynitride, while the carbon rich particles are most likely a form of graphite. Microscopic cross-sectional FTIR determined that inclusions deeper in the wafer contain more oxygen than those near the top-surface. Chemical reactions between these included particles and molten Si are discussed based on a thermodynamic analysis. It is concluded that α-Si3N4 particles, formed either through Si–N2 reaction or incorporated from refractory materials, transform into oxynitrides in the deeper region where the dissolved oxygen exceeds 2.8×1017 cm−3.}, number={2-4}, journal={JOURNAL OF CRYSTAL GROWTH}, author={Lu, JG and Rozgonyi, G and Rand, J and Jonczyk, R}, year={2004}, month={Sep}, pages={599–605} } @article{karoui_karoui_rozgonyi_hourai_sueoka_2004, title={Characterization of nucleation sites in nitrogen doped czochralski silicon by density functional theory and molecular mechanics}, volume={95-96}, DOI={10.4028/www.scientific.net/ssp.95-96.99}, abstractNote={Extended defect nucleation and growth in nitrogen doped Czochralski silicon crystals are investigated in terms of trapping vacancy and oxygen atoms by ni trogen-pairs using molecular mechanics. The results have been correlated to the formation ener gy and stability of nitrogen-vacancyoxygen complexes obtained by ab-initio density functional theory. We found that N2 in a split interstitial position and V2N2 when formed from VN2 are very stable and have a strong affinity for oxygen, whereas the interaction energy between these defects and vacanc ies is weak. VN2 can only be weakly coupled to oxygen atoms, whereas it reconstructs into stable V 2N2 by trapping a vacancy. These results are in agreement with the degree of stability of nitrogen-vacancy-ox ygen complexes and indicate that N 2 and V2N2 are nucleation centers for oxygen precipitation rather than for void formation.}, number={2004}, journal={Diffusion and Defect Data. [Pt. B], Solid State Phenomena}, author={Karoui, F. S. and Karoui, A. and Rozgonyi, G. A. and Hourai, M. and Sueoka, K.}, year={2004}, pages={99–104} } @article{lu_wagener_rozgonyi_rand_jonczyk_2003, title={Effects of grain boundary on impurity gettering and oxygen precipitation in polycrystalline sheet silicon}, volume={94}, ISSN={["0021-8979"]}, DOI={10.1063/1.1578699}, abstractNote={The effects of grain boundaries (GB) in polycrystalline sheet silicon on impurity gettering and oxygen precipitation were investigated by electron beam induced current (EBIC), deep level transient spectroscopy (DLTS), micro-Fourier-transform infrared spectroscopy (FTIR), and preferential etching/Normaski optical microscopy techniques. Both as-grown and thermally processed wafers were studied. A correlation between GB density and transition metal concentration was quantitatively established by combining DLTS and EBIC studies. It was found that four deep levels arising from Fe–B, Fe–Al, Cr–B, and Fei were present in the as-grown sample, and their concentrations decrease with increasing GB density. GB gettering was further verified by the presence of an EBIC image contrast halo around the GB. Preferential etching also revealed a precipitate density of 2×107 cm−2 on the GB. After processing, a clearly defined oxygen precipitate denuded zone formed around the GB with the interstitial oxygen concentration [Oi] decreased from 14.4 to 2.2×1017 cm−3. Micro-FTIR showed that, for both processed and as-grown samples, more silicon oxynitride appears in the GB than in the intragrain region. Since nitrogen enhances oxygen precipitation, it is likely that nitrogen preferentially precipitated on the GB during the wafer formation process and resulted in a nitrogen depletion zone, where oxygen precipitation was further suppressed and a denuded zone formed.}, number={1}, journal={JOURNAL OF APPLIED PHYSICS}, author={Lu, JG and Wagener, M and Rozgonyi, G and Rand, J and Jonczyk, R}, year={2003}, month={Jul}, pages={140–144} } @article{kvit_yankov_duscher_rozgonyi_glasko_2003, title={Formation of nanoscale voids and related metallic impurity gettering in high-energy ion-implanted and annealed epitaxial silicon}, volume={83}, ISSN={["0003-6951"]}, DOI={10.1063/1.1601678}, abstractNote={We have examined nanovoid formation, Fe gettering, and Fe clustering phenomena occurring in epitaxial silicon layers implanted with MeV Si ions. Insights into these phenomena as a function of depth have been gained from detailed analyses by Z-contrast imaging in conjunction with electron energy-loss spectroscopy. Our work has shown at the nanoscale structural and chemical levels that the defects produced by MeV self-ion implantation between the surface and the ion projected range Rp (i.e., in the so-called Rp/2 region) are voids, which provide extremely efficient and aggressive metallic impurity gettering. It has been proposed that the gettering does not occur via chemisorption or silicidation layering on the internal surface of the void walls, as in the well-known case of helium-induced cavities, but rather proceeds in a mode of metal–metal atom binding in the vicinity of the Rp/2 voids.}, number={7}, journal={APPLIED PHYSICS LETTERS}, author={Kvit, A and Yankov, RA and Duscher, G and Rozgonyi, G and Glasko, JM}, year={2003}, month={Aug}, pages={1367–1369} } @article{stoddard_karoui_duscher_kvit_rozgonyi_2003, title={In situ point defect generation and agglomeration during electron-beam irradiation of nitrogen-doped Czochralski silicon}, volume={6}, ISSN={["1944-8775"]}, DOI={10.1149/1.1614471}, abstractNote={Samples of Czochralski silicon were observed after irradiation by a convergent electron beam in a transmission electron microscope. In a nitrogen-doped sample, the 200 keV electrons induced a vacancy-rich region containing point-defect clusters, surrounded by a ring rich in self-interstitials. No comparable effect existed in nitrogen-free reference samples. It is proposed that Frenkel pairs, created by electron collisions, are separated and stabilized by nitrogen or related complexes. Some interstitials become free to diffuse while the nitrogen, vacancies and oxygen agglomerate. This study demonstrates that the initial formation of voids and precipitate nuclei from point defects can be observed at low temperatures. © 2003 The Electrochemical Society. All rights reserved.}, number={11}, journal={ELECTROCHEMICAL AND SOLID STATE LETTERS}, author={Stoddard, N and Karoui, A and Duscher, G and Kvit, A and Rozgonyi, G}, year={2003}, month={Nov}, pages={G134–G136} } @article{rozgonyi_karoui_kvit_duscher_2003, title={Nano-scale analysis of precipitates in nitrogen-doped Czochralski silicon}, volume={66}, ISSN={["1873-5568"]}, DOI={10.1016/S0167-9317(02)00923-1}, abstractNote={Nitrogen-doped Czochralski (CZ) silicon wafers were heat treated with Lo-Hi annealing in argon. Nanoscale defects were then examined by high resolution transmission electron microscopy (HRTEM), scanning transmission electron microscopy (STEM) in the Z-contrast mode, and electron energy loss spectroscopy (EELS) analyses using a field emission JEOL 2010 with a resolution below 2 A. The structures of precipitates, stacking faults and interstitial aggregates were found to depend on their location relative to the wafer surface. Precipitate composition, strain at the interface and interface roughness were obtained and are discussed in connection with the point defects generated during crystal growth and modified during wafer annealing. An excellent correlation was found between Z-contrast line scans across the precipitates and the N to O concentration ratio determined with EELS. In the precipitate central region that ratio is between 1 and 6%, whereas at precipitate boundaries it reaches 17%.}, number={1-4}, journal={MICROELECTRONIC ENGINEERING}, author={Rozgonyi, GA and Karoui, A and Kvit, A and Duscher, G}, year={2003}, month={Apr}, pages={305–313} } @article{karoui_karoui_rozgonyi_hourai_sueoka_2003, title={Structure, energetics, and thermal stability of nitrogen-vacancy-related defects in nitrogen doped silicon}, volume={150}, ISSN={["1945-7111"]}, DOI={10.1149/1.1621418}, abstractNote={The electronic structure, formation energy, and thermal stability of nitrogen-vacancy related complexes in silicon have been investigated using density functional theory and semi-empirical Hartree-Fock calculations. The calculated energies of formation in the ground state showed that VN 2 was not stable, whereas V 2 N 2 when formed from VN 2 was the most stable, followed by N 2 and V 2 N 2 formed from a divacancy. The calculated free energy changes of the considered chemical reactions confirmed the low stability of VN 2 compared to V 2 N 2 . The latter can form during crystal growth from VN 2 , whereas reactions between N 2 and divacancy can also occur upon wafer heating. At low nitrogen concentration (∼5 X 10 13 cm -3 ), only about 10% of vacancy concentration was converted into VN 2 , while at a high nitrogen concentration (∼10 16 cm -3 ) about 75% of vacancies are trapped by nitrogen. V 2 N 2 appeared to create a potential well of -2.4 eV for oxygen and about -0.3 eV for vacancies, suggesting that the stable V 2 N 2 is a nucleus for oxygen precipitation while it is a weak trapping center for vacancies.}, number={12}, journal={JOURNAL OF THE ELECTROCHEMICAL SOCIETY}, author={Karoui, A and Karoui, FS and Rozgonyi, GA and Hourai, M and Sueoka, K}, year={2003}, month={Dec}, pages={G771–G777} } @article{yoganand_raghuveer_jagannadham_wu_karoui_rozgonyi_2002, title={Multilayer TiC/TiN diffusion barrier films for copper}, volume={80}, ISSN={["1077-3118"]}, url={http://www.scopus.com/inward/record.url?eid=2-s2.0-79955988332&partnerID=MN8TOARS}, DOI={10.1063/1.1430027}, abstractNote={TiC/TiN thin films deposited by reactive magnetron sputtering on Si (100) substrates were investigated by transmission electron microscopy for microstructure and by deep level transient spectroscopy (DLTS) for diffusion barrier against copper. TiN thin films deposited on Si substrates at a substrate temperature of 600 °C were textured, and TiC thin films deposited at the same temperature were polycrystalline. TiC/TiN multilayer films also showed the same characteristics with the formation of an additional interaction layer. The diffusion barrier characteristics of the TiC/TiN/Si were determined by DLTS and the results showed that the films completely prevented diffusion of copper into Si.}, number={1}, journal={APPLIED PHYSICS LETTERS}, author={Yoganand, SN and Raghuveer, MS and Jagannadham, K and Wu, L and Karoui, A and Rozgonyi, G}, year={2002}, month={Jan}, pages={79–81} } @article{karoui_karoui_kvit_rozgonyi_yang_2002, title={Role of nitrogen related complexes in the formation of defects in silicon}, volume={80}, ISSN={["1077-3118"]}, DOI={10.1063/1.1462874}, abstractNote={Defect size and density distributions were obtained as a function of depth in nitrogen doped CZ silicon (N-CZ) following Hi–Lo–Hi and Lo–Hi annealing, using an oxygen precipitate profiler. The defects were also delineated by Wright etching and Nomarski optical microscopy on both cleaved and bevel polished samples. In addition to the enhanced precipitation and absence of voids previously reported for N-CZ Si, an unexpected mode of precipitation has been found near the annealed wafer surface, just above the traditional denuded zone. This oxynitride precipitate is discussed with regard to N-related complex interactions and point defect supersaturations/injection. High resolution transmission electron microscopy revealed that most precipitates have an octahedral shape with two distinct amorphous phases, which reflect a transition from an initial phase containing both N and O to one with primarily O, as verified with Z-contrast TEM and electron energy loss spectroscopy.}, number={12}, journal={APPLIED PHYSICS LETTERS}, author={Karoui, A and Karoui, FS and Kvit, A and Rozgonyi, GA and Yang, D}, year={2002}, month={Mar}, pages={2114–2116} } @article{karoui_karoui_yang_rozgonyi_2002, title={Role of nitrogen-related complexes in the formation of defects in N-Cz silicon wafers}, volume={82-84}, number={2002}, journal={Gettering and defect engineering in semiconductor technology}, author={Karoui, A. and Karoui, F. S. and Yang, D. and Rozgonyi, G. A.}, year={2002}, pages={69–74} } @article{ono_sasaki_kirk_rozgonyi_2000, title={Electron beam induced current contrast of oxygen precipitation related defects in Czochralski silicon}, volume={78-79}, number={2000}, journal={Diffusion and Defect Data. [Pt. B], Solid State Phenomena}, author={Ono, T. and Sasaki, T. and Kirk, H. and Rozgonyi, G. A.}, year={2000}, pages={237–252} } @article{rozgonyi_glasko_beaman_koveshnikov_2000, title={Gettering issues using MeV ion implantation}, volume={72}, ISSN={["0921-5107"]}, DOI={10.1016/s0921-5107(99)00506-1}, abstractNote={Abstract MeV implantation has generated interest as a gettering option in silicon since it was established that under the appropriate conditions of irradiation fluence, substrate oxygen content, and annealing treatment, at least two distinct regions, denoted as R p and R p /2, getter impurities (M. Tamura, T. Ando, O.K., Nucl. Instrum. Methods Phys. Res. B 59/60 (1991) 572; A. Agarwal, K. Christensen, D. Venables, D.M. Maher, G.A. Rozgonyi, Appl. Phys. Lett. 69 (1996) 3899). In the present work we report on the thermal stability of Fe gettered at R p due to MeV ion implantation-induced dislocation loops in Fe contaminated CZ Si wafers, and an activation energy for the release of gettered Fe of 0.80 eV. It has also been determined that, the gettering mechanism in the R p /2 region in epitaxial Si for high MeV ion doses (≈5×10 15 Ge cm −2 ) is vacancy-related, since TEM analysis revealed 4–11-nm diameter voids. Under the annealing conditions studied, these voids were found to be more efficient at Fe capture than R p defects.}, number={2-3}, journal={MATERIALS SCIENCE AND ENGINEERING B-SOLID STATE MATERIALS FOR ADVANCED TECHNOLOGY}, author={Rozgonyi, GA and Glasko, JM and Beaman, KL and Koveshnikov, SV}, year={2000}, month={Mar}, pages={87–92} } @article{kawamura_kanzawa_kojima_rozgonyi_2000, title={Reconstructed (12,2,7) Si surface structure observed by scanning tunneling microscopy}, volume={87}, ISSN={["0021-8979"]}, DOI={10.1063/1.371930}, abstractNote={A series of reconstructed high-index Si surfaces, with angle β from the [111] to [11̄0] direction varying between 10° and 35° (in increments of 5°) were systematically studied by ultrahigh vacuum scanning tunneling microscopy. The reconstruction of the (12, 2, 7) surface with β=30° as a typical example of the series was described in detail. Fourier transforms revealed a (2×2) structure of the terrace, the splitting lattice on the step wall, and diffuse streaks from the kinks. The results were compared with other high-index surfaces of the β series. The reconstructed terrace structures were separated into two groups by the boundary between β=20° and 25°. With regard to the reconstructed step wall structures, a remarkable characteristic pattern of these high-index surfaces was clarified, namely that they are composed of several splitting lattices. The degree of splitting proved to be closely proportional to the effective dangling bond density. The diffuse streaks from the kinks were also observed as a common phenomenon of this series.}, number={2}, journal={JOURNAL OF APPLIED PHYSICS}, author={Kawamura, T and Kanzawa, T and Kojima, S and Rozgonyi, GA}, year={2000}, month={Jan}, pages={711–716} } @article{ono_rozgonyi_horie_miyazaki_tsuya_1999, title={Analysis of capacitor breakdown mechanisms due to crystal-originated pits}, volume={20}, ISSN={["0741-3106"]}, DOI={10.1109/55.791924}, abstractNote={The extent to which crystal originated defect pits (COPs) will enhance capacitor B-mode failures has been examined as a function of substrate carrier type/dopant concentration and bias mode (accumulation/inversion). An unexpected immunity to COPs, found for n-type capacitors biased into accumulation, could be readily explained by invoking Fowler-Nordheim (FN) tunneling variations due to the morphology of the capacitor electrodes, as revealed by cross-sectional TEM on simulated COPs formed by KOH anisotropic etching.}, number={10}, journal={IEEE ELECTRON DEVICE LETTERS}, author={Ono, T and Rozgonyi, G and Horie, H and Miyazaki, M and Tsuya, H}, year={1999}, month={Oct}, pages={504–506} } @article{kirk_radzimski_romanowski_rozgonyi_1999, title={Bias dependent contrast mechanisms in EBIC images of MOS capacitors}, volume={146}, ISSN={["0013-4651"]}, DOI={10.1149/1.1391799}, abstractNote={Defects and inhomogeneities in the electrical properties of metal oxide silicon capacitors are analyzed by scanning electron microscopy, using the electron beam induced current technique (MOS/EBIC). All capacitors were analyzed in their as-fabricated or prebreakdown condition. The collected signals and image contrast are found to be highly dependent on the gate-to-substrate bias applied during MOS/EBIC examination, and this bias-dependence is shown to be correlated with the nature and physical location of the defect. Specific MOS defects were selected for this study according to their position in the substrate, in the oxide, or at the Si/SiO 2 interface. Substrate defects examined were misfit dislocations in epitaxial Si(Ge) on Si. Interfacial inhomogeneities included thermally oxidized, reactive ion etched (RIE) Si surfaces, and SiO 2 precipitates or D-defects which extend to meet the Si surface. Oxide layer inhomogeneities were also detectable which exhibited a strong contrast dependence on the oxide electric field strength.}, number={4}, journal={JOURNAL OF THE ELECTROCHEMICAL SOCIETY}, author={Kirk, HR and Radzimski, Z and Romanowski, A and Rozgonyi, GA}, year={1999}, month={Apr}, pages={1529–1535} } @article{koveshnikov_choi_yarykin_rozgonyi_1999, title={Drift of interstitial iron in a space charge region of p-type Si Schottky diode}, volume={274}, number={1999 Dec.}, journal={Physica. B, Condensed Matter}, author={Koveshnikov, S. and Choi, B. and Yarykin, N. and Rozgonyi, G.}, year={1999}, pages={395–397} } @article{ono_asayama_horie_hourai_sueoka_tsuya_rozgonyi_1999, title={Effect of heavy boron doping on oxide precipitate growth in Czochralski silicon}, volume={146}, ISSN={["0013-4651"]}, DOI={10.1149/1.1391921}, abstractNote={Oxide precipitate growth in boron‐doped Czochralski silicon wafers with resistivities ranging from 6 to 40 mΩ cm has been studied following prolonged annealing from 800 to 1000°C. Transmission electron microscopy revealed that (i) the growth rate of oxide platelet precipitates is proportional to the square root of time in 40 mΩ cm samples and (ii) the precipitate morphology changes from plate to polyhedral and strain around the precipitate decreases during annealing at 900°C in 6, 9, and 18 mΩ cm samples. These results indicate that changes in precipitate morphology occur because the oxygen precipitation and boron atom size effects are enhanced by increasing boron concentration. © 1999 The Electrochemical Society. All rights reserved.}, number={6}, journal={JOURNAL OF THE ELECTROCHEMICAL SOCIETY}, author={Ono, T and Asayama, E and Horie, H and Hourai, M and Sueoka, K and Tsuya, H and Rozgonyi, GA}, year={1999}, month={Jun}, pages={2239–2244} } @article{cho_yarykin_brown_kononchuk_rozgonyi_zuhr_1999, title={Evolution of deep-level centers in p-type silicon following ion implantation at 85 K}, volume={74}, ISSN={["0003-6951"]}, DOI={10.1063/1.123519}, abstractNote={In situ deep-level transient spectroscopy measurements have been carried out on p-type silicon following MeV He, Si, and Ge ion implantation at 85 K. Deep levels corresponding to intrinsic and impurity-related point defects are only detected after annealing at temperatures above 200 K. In addition to divacancies, interstitial carbon, and a carbon–oxygen complex, the formation of another defect, denoted as K2, has been observed during annealing at 200–230 K in epitaxial wafers, and at 200–300 K in Czochralski grown material. The energy level of the K2 defect is located 0.36 eV above the valence band, which is very close to a previously observed level of the carbon–oxygen pair. The relative concentration of this defect is ∼10 times higher in samples implanted with Ge than in those implanted with He. Due to its formation temperature, equal concentration in epitaxial and Czochralski grown wafers, and absence in n-type samples, the K2 trap has been tentatively identified as a vacancy-related complex which probably contains boron.}, number={9}, journal={APPLIED PHYSICS LETTERS}, author={Cho, CR and Yarykin, N and Brown, RA and Kononchuk, O and Rozgonyi, GA and Zuhr, RA}, year={1999}, month={Mar}, pages={1263–1265} } @article{beaman_glasko_koveshnikov_rozgonyi_1999, title={Gettering at vacancy and interstitial-rich regions in MeV ion implanted silicon}, volume={70}, number={1999}, journal={Diffusion and Defect Data. [Pt. B], Solid State Phenomena}, author={Beaman, K. L. and Glasko, J. M. and Koveshnikov, S. V. and Rozgonyi, G. A.}, year={1999}, pages={247–252} } @article{yarykin_cho_zuhr_rozgonyi_1999, title={In-situ photoexcitation-induced perturbations of defect complex concentration and distribution in silicon implanted with light and heavy ions}, volume={70}, number={1999}, journal={Diffusion and Defect Data. [Pt. B], Solid State Phenomena}, author={Yarykin, N. and Cho, C. R. and Zuhr, R. A. and Rozgonyi, G. A.}, year={1999}, pages={397–402} } @article{yarykin_cho_zuhr_rozgonyi_1999, title={In-situ studies of point-defect complexes in silicon implanted with heavy MeV ions}, volume={274}, number={1999 Dec.}, journal={Physica. B, Condensed Matter}, author={Yarykin, N. and Cho, C. R. and Zuhr, R. and Rozgonyi, G.}, year={1999}, pages={485–488} } @article{beaman_kononchuk_koveshnikov_osburn_rozgonyi_1999, title={Lateral gettering of Fe on bulk and silicon-on-insulator wafers}, volume={146}, ISSN={["1945-7111"]}, DOI={10.1149/1.1391867}, abstractNote={Laterally displaced gettering sites have been studied as an alternative to traditional internal gettering and back-side gettering sites. Fe was diffused laterally and captured, first by coulombic pairing with B in p-type Si, and then by strategically placed ion implantation induced dislocation loops. This localization of Fe was tracked by both deep level transient spectroscopy and capacitance-voltage measurements. As proof of the viability of the gettering technique, laterally displaced gettering sites were formed adjacent to capacitors on various silicon-on-insulator (SOI) substrate types. Both implantation induced dislocation loops and P diffusion were used for gettering. An improvement in gate oxide integrity was observed for capacitors with lateral gettering on all SOI types studied.}, number={5}, journal={JOURNAL OF THE ELECTROCHEMICAL SOCIETY}, author={Beaman, KL and Kononchuk, O and Koveshnikov, S and Osburn, CM and Rozgonyi, GA}, year={1999}, month={May}, pages={1925–1928} } @article{ono_romanowski_asayama_horie_sueoka_tsuya_rozgonyi_1999, title={Oxide precipitate-induced dislocation generation in heavily boron-doped Czochralski silicon}, volume={146}, ISSN={["0013-4651"]}, DOI={10.1149/1.1392496}, abstractNote={Dislocation generation associated with oxide precipitates in heavily boron-doped Czochralski silicon wafers with resistivities of 9, 18, and 40 mΩ cm has been studied following prolonged isothermal annealing from 800 to 1000°C. Transmission electron microscopy observations revealed (i) the critical precipitate size for punched-out dislocations to form in 9 and 18 mΩ cm wafers was smaller than 40 nm in 9 and 18 mΩ cm wafers, while larger than 55 nm in 40 mΩ cm samples; (ii) the precipitate density was higher than 10 12 cm -3 in 9 and 18 mΩ cm wafers, and below 10 11 cm -3 in 40 mΩ cm wafers annealed at 800 and 900°C, respectively. The strain around a precipitate was estimated and it was concluded that the higher supersaturation of silicon interstitials in the 9 and 18 mΩ cm wafers was due to the higher precipitate density, which in turn was likely to be the main cause of the reduction in critical precipitate size.}, number={9}, journal={JOURNAL OF THE ELECTROCHEMICAL SOCIETY}, author={Ono, T and Romanowski, A and Asayama, E and Horie, H and Sueoka, K and Tsuya, H and Rozgonyi, GA}, year={1999}, month={Sep}, pages={3461–3465} } @article{ono_rozgonyi_asayama_horie_tsuya_sueoka_1999, title={Oxygen diffusion in heavily antimony-, arsenic-, and boron-doped Czochralski silicon wafers}, volume={74}, ISSN={["0003-6951"]}, DOI={10.1063/1.123210}, abstractNote={The effect of dopant-type, antimony (Sb), arsenic (As), and boron (B), on the outdiffusion of oxygen in heavily doped Czochralski (Cz) silicon wafers has been investigated using secondary ion mass spectroscopy. The results indicate that, although oxygen diffusion in Cz silicon is retarded in heavily B- and As-doped wafers during low temperature annealing (800 °C), it is not influenced by heavy Sb doping. This indicates that charge effects and atom size effects have negligible influence on the diffusion of oxygen. The B and As diffusion retardation effect is attributed to the existence of dopant-oxygen complexes. The oxygen solubility was largest in the most heavily B-doped samples annealed at low temperature.}, number={24}, journal={APPLIED PHYSICS LETTERS}, author={Ono, T and Rozgonyi, GA and Asayama, E and Horie, H and Tsuya, H and Sueoka, K}, year={1999}, month={Jun}, pages={3648–3650} } @article{ono_rozgonyi_au_messina_goodall_huff_1999, title={Oxygen precipitation behavior in 300 mm polished Czochralski silicon wafers}, volume={146}, ISSN={["0013-4651"]}, DOI={10.1149/1.1392555}, abstractNote={The oxygen precipitation behavior in large diameter (300 mm) Czochralski silicon polished wafers with initial oxygen concentrations between 25-36 parts per million atomic and low carbon content, has been studied following two step heat-treatments (low-high annealing). It was found that an oxygen precipitation retardation and recovery phenomena occurred. Transmission electron microscopy observations showed that extended defect formation is drastically changed from punched-out dislocations in precipitate retardation samples, to stacking faults in precipitation recovery samples. The precipitation retardation phenomenon is consistent with a previous model on smaller diameter wafers; however, the current experimental results for 300 mm wafers indicate platelet precipitate growth during the first low temperature annealing plays a key role in the oxygen precipitation recovery phenomenon.}, number={10}, journal={JOURNAL OF THE ELECTROCHEMICAL SOCIETY}, author={Ono, T and Rozgonyi, GA and Au, C and Messina, T and Goodall, RK and Huff, HR}, year={1999}, month={Oct}, pages={3807–3811} } @article{brown_kononchuk_rozgonyi_1999, title={Simulation of metallic impurity gettering in silicon by MeV ion implantation}, volume={148}, number={1-4}, journal={Nuclear Instruments & Methods in Physics Research. Section A, Accelerators, Spectrometers, Detectors, and Associated Equipment}, author={Brown, R. A. and Kononchuk, O. and Rozgonyi, G. A.}, year={1999}, pages={322–328} } @article{romanowski_rozgonyi_tamatsuka_1999, title={Simulation of void and oxygen precipitation processes during high temperature annealing of silicon wafers}, volume={85}, ISSN={["0021-8979"]}, DOI={10.1063/1.370144}, abstractNote={The kinetics for dissolution/growth of defects in Czochralski silicon wafers during a 1 h high temperature annealing at 1100 °C has been investigated. The size and distribution of point defects such as vacancy, self-interstitial and oxygen interstitial, are simulated for oxygen and hydrogen ambient annealing. The boundary conditions are analyzed separately for hydrogen and oxygen annealing. A deterministic homogeneous model is used for describing the defect kinetics. The self-interstitial injection rate during oxide annealing is calculated from the Deal-Grove model. Simulated void and oxygen size distributions are compared to B- and C-mode capacitor failure distribution functions. Experimental and theoretical data show that voids can be dissolved during either oxygen or hydrogen annealing, while oxygen precipitates are dissolved during hydrogen annealing and only partially dissolved during oxygen annealing.}, number={9}, journal={JOURNAL OF APPLIED PHYSICS}, author={Romanowski, A and Rozgonyi, G and Tamatsuka, M}, year={1999}, month={May}, pages={6408–6414} } @article{sasaki_ono_rozgonyi_1999, title={Size distribution of oxide precipitates in annealed Czochralski silicon}, volume={2}, ISSN={["1099-0062"]}, DOI={10.1149/1.1390915}, abstractNote={The size distribution of oxide precipitates in Czochralski silicon has been determined using an optical precipitate profiler on two‐ step annealed wafers with and without a high‐temperature dissolution annealing . The dissolution annealing significantly changed oxygen precipitation, probably by changing the size distribution of grown‐in nuclei. For wafers without the dissolution annealing, the size distribution becomes narrower, with a smaller mean size for increasing length of treatment. It is proposed that the size‐dependent nucleus dissolution is due to the removal of point defects from the precipitate/matrix interface or its vicinity. ©1999 The Electrochemical Society}, number={11}, journal={ELECTROCHEMICAL AND SOLID STATE LETTERS}, author={Sasaki, T and Ono, T and Rozgonyi, GA}, year={1999}, month={Nov}, pages={589–591} } @article{yarykin_cho_rozgonyi_zuhr_1999, title={The impact of in situ photoexcitation on the formation of vacancy-type complexes in silicon implanted at 85 and 295 K}, volume={75}, ISSN={["1077-3118"]}, DOI={10.1063/1.124335}, abstractNote={Photoexcitation of silicon during low-fluence implantation with MeV Si and Ge ions is observed to suppress vacancy-type point-defect formation, as determined by in situ deep-level transient spectroscopy. The A-center formation after low-temperature implantation is extended over a wide temperature interval indicating that electrically inactive clusters, which emit vacancies during annealing, are formed in the end-of-range region during implantation at 85 K. The number of vacancies stored in these clusters is influenced by low-temperature in situ photoexcitation.}, number={2}, journal={APPLIED PHYSICS LETTERS}, author={Yarykin, N and Cho, CR and Rozgonyi, GA and Zuhr, RA}, year={1999}, month={Jul}, pages={241–243} } @article{kononchuk_bondarenko_rozgonyi_1998, title={Combined MOS/EBIC and TEM study of electrically active defects in SOI wafers}, volume={63-4}, number={1998}, journal={Diffusion and Defect Data. [Pt. B], Solid State Phenomena}, author={Kononchuk, O. and Bondarenko, I. and Rozgonyi, G.}, year={1998}, pages={61–67} } @article{kononchuk_korablev_yarykin_rozgonyi_1998, title={Diffusion of iron in the silicon dioxide layer of silicon-on-insulator structures}, volume={73}, ISSN={["0003-6951"]}, DOI={10.1063/1.122128}, abstractNote={The redistribution of iron implanted into the oxide layer of silicon-on-insulator structures has been measured using the secondary ion mass spectroscopy technique after annealing at 900–1050 °C. Iron diffusion has been found to be much faster in the oxide prepared by the separation-byimplantation-of-oxygen (SIMOX) procedure compared to the thermally grown oxide in the bonded and etched-back structures. In the latter case, the Fe diffusivity exhibits a thermal activation with an energy of 2.8 eV, confirming the literature data on silica glass. In the SIMOX oxide, the diffusivity depends only weakly on temperature, indicative of an essentially activation-free diffusion mechanism. Gettering of Fe at below-the-buried-oxide defects in SIMOX wafers has been observed. No iron segregation has been detected at the SiO2–Si interfaces.}, number={9}, journal={APPLIED PHYSICS LETTERS}, author={Kononchuk, O and Korablev, KG and Yarykin, N and Rozgonyi, GA}, year={1998}, month={Aug}, pages={1206–1208} } @article{romanowski_buczkowski_karoui_rozgonyi_1998, title={Frequency-resolved microwave reflection photoconductance}, volume={83}, ISSN={["0021-8979"]}, DOI={10.1063/1.367946}, abstractNote={The effect of the carrier recombination process in silicon on the microwave reflection coefficient is analyzed in the frequency domain. The process is described using a two level recombination/trapping model. Carrier recombination kinetics are characterized by four parameters, two of which are related to the recombination and the other to the trapping processes. These parameters are evaluated for Czochralski silicon wafers based on Nyquist plots. In the evaluation procedure, a nonlinear simplex method is used for fitting the experimental data to the model.}, number={12}, journal={JOURNAL OF APPLIED PHYSICS}, author={Romanowski, A and Buczkowski, A and Karoui, A and Rozgonyi, GA}, year={1998}, month={Jun}, pages={7730–7735} } @article{brown_kononchuk_rozgonyi_koveshnikov_knights_simpson_gonzalez_1998, title={Impurity gettering to secondary defects created by MeV ion implantation in silicon}, volume={84}, ISSN={["0021-8979"]}, DOI={10.1063/1.368438}, abstractNote={Impurities in MeV-implanted and annealed silicon may be trapped at interstitial defects near the projected ion range, Rp, and also at vacancy-related defects at approximately Rp/2. We have investigated the temperature dependence of impurity trapping at these secondary defects, which were preformed by annealing at 900 °C. The binding energies of Fe, Ni, and Cu are greater at the vacancy-related defects than at extrinsic dislocation loops. During subsequent processing at temperatures up to 900 °C, the amount of these impurities trapped at Rp/2 increases with decreasing temperature while the amount trapped at Rp decreases, with most of the trapped metals located at Rp/2 in samples processed at temperatures ≲ 700 °C. However, intrinsic oxygen is trapped at both types of defects; this appears to have little effect on the trapping of metallic impurities at extrinsic dislocations, but may inhibit or completely suppress the trapping at vacancy-related defects.}, number={5}, journal={JOURNAL OF APPLIED PHYSICS}, author={Brown, RA and Kononchuk, O and Rozgonyi, GA and Koveshnikov, S and Knights, AP and Simpson, PJ and Gonzalez, F}, year={1998}, month={Sep}, pages={2459–2465} } @article{koveshnikov_rozgonyi_1998, title={Mechanism of iron gettering in MeV Si ion implanted epitaxial silicon}, volume={84}, ISSN={["0021-8979"]}, DOI={10.1063/1.368462}, abstractNote={The gettering properties of the two damage regions, namely, a near-surface vacancy-rich region, Rp/2 and a buried layer of extended defects near the MeV Si ion projected range, Rp, have been quantitatively determined by means of secondary ion mass spectrometry and deep level transient spectroscopy techniques. To isolate the simultaneous and competitive gettering between iron and oxygen, the MeV defects were introduced into epitaxial silicon doped with boron. Czochralski Si samples were also used for comparison. Experiments on isochronal and isothermal annealing of Fe contaminated samples in conjunction with the rapid quenching procedure allowed us to establish the dominating gettering mechanisms in the two damage regions. Thus, gettering in the Rp region was driven by relaxation of supersaturated Fe, while the segregation-induced gettering mechanism was operative in the Rp/2 zone. As a result, the concentration of Fe, which was remained ungettered at elevated temperature, was well below the solid solubility limit. The major gettering parameters of MeV defects, such as gettering capacity, efficiency, and thermal stability have been determined.}, number={6}, journal={JOURNAL OF APPLIED PHYSICS}, author={Koveshnikov, SV and Rozgonyi, GA}, year={1998}, month={Sep}, pages={3078–3084} } @article{tamatsuka_radzimski_rozgonyi_oka_kato_kitagawara_1998, title={Medium field breakdown origin on metal oxide semiconductor capacitor containing grown-in Czochralski silicon crystal defects}, volume={37}, ISSN={["0021-4922"]}, DOI={10.1143/JJAP.37.1236}, abstractNote={The medium field breakdown of metal oxide semiconductor capacitor due to the Czochralski silicon crystal originated defect was studied in view of both electrical and structural analyses. By analyzing the local tunneling current which initiates the medium field breakdown, phenomenological defect sizes were calculated from the local tunneling current by assuming the local oxide thinning model. They were the defect diameter as 5 to 50 nm and the local oxide thinning as ∼25 nm. These data were confirmed by direct defect observation using high precision defect isolation procedure followed by transmission electron microscopy. Direct observation revealed that the real defect size was ∼200 nm which correlated well with other recently reported works. The real local oxide thinning,however,was not as large as phenomenological calculation. To explain the differences between phenomenological and real local oxide thinning, the poly-Si grain protrusion induced stress model was proposed.}, number={3B}, journal={JAPANESE JOURNAL OF APPLIED PHYSICS PART 1-REGULAR PAPERS SHORT NOTES & REVIEW PAPERS}, author={Tamatsuka, M and Radzimski, Z and Rozgonyi, GA and Oka, S and Kato, M and Kitagawara, Y}, year={1998}, month={Mar}, pages={1236–1239} } @article{beaman_agarwal_kononchuk_koveshnikov_bondarenko_rozgonyi_1997, title={Gettering of iron in silicon-on-insulator wafers}, volume={71}, ISSN={["1077-3118"]}, DOI={10.1063/1.119741}, abstractNote={Gettering of Fe in silicon-on-insulator material has been investigated on both the bonded and separation by implantation of oxygen (SIMOX) platforms. Reduction of electrically active iron in intentionally contaminated and annealed wafers has been measured by deep level transient spectroscopy. These data, coupled with structural characterization techniques, such as transmission electron microscopy and preferential chemical etching, provide evidence that structural postimplantation damage below the buried oxide (BOX) in SIMOX wafers is an effective site for gettering of iron with the iron gettering efficiency varying with the SIMOX processing. Gettering was not observed in bonded wafers, and the lower BOX interface did not provide any iron gettering in either bonded or SIMOX wafers.}, number={8}, journal={APPLIED PHYSICS LETTERS}, author={Beaman, KL and Agarwal, A and Kononchuk, O and Koveshnikov, S and Bondarenko, I and Rozgonyi, GA}, year={1997}, month={Aug}, pages={1107–1109} } @article{brown_kononchuk_bondarenko_romanowski_radzimski_rozgonyi_gonzalez_1997, title={Metallic impurity gettering and secondary defect formation in megaelectron volt self-implanted Czochralski and float-zone silicon}, volume={144}, ISSN={["0013-4651"]}, DOI={10.1149/1.1837910}, abstractNote={Megaelectron volt (MeV) self-implantation has been investigated as a means of producing buried defect layers for gettering metallic impurities in Czochralski (CZ) and float-zone (FZ) silicon. The properties of implanted and annealed wafers were studied by generation lifetime (Zerbst) analysis of transient capacitance data, capacitance-voltage measurements, deep-level transient spectroscopy, scanning electron-beam-induced current microscopy, transmission electron microscopy, optical microscopy with preferential chemical etching, and secondary ion mass spectroscopy. We found that metallic contaminants such as Fe and Cu were effectively gettered to buried extended defect layers formed by implantation of ion fluences ≤1 x 10 15 Si cm -2 . For example, the concentration of iron in regions near the buried defects can be reduced to below 10 10 cm -3 in samples annealed at 900°C. The region above the damage layer appears to be free of electrically active defects, having very high generation lifetime values, and is therefore suitable for device processing. However, the structure and width of the buried defect band is sensitive to the implanted ion fluence and the oxygen content of the wafers. For example, the defect layers formed by high ion fluences (∼10 15 cm -2 ) are wider in FZ wafers than in CZ wafers. For fluences 1 x 10 14 cm 2 , dislocations extend from the buried damage band in both directions during annealing and are observed at depths up to 10 μm. These dislocations intersect the wafer surface in both CZ and FZ wafers, making fluences lower than ≃ 5 x 10 14 cm -2 unsuitable for device fabrication.}, number={8}, journal={JOURNAL OF THE ELECTROCHEMICAL SOCIETY}, author={Brown, RA and Kononchuk, O and Bondarenko, I and Romanowski, A and Radzimski, Z and Rozgonyi, GA and Gonzalez, F}, year={1997}, month={Aug}, pages={2872–2881} } @article{brown_kononchuk_radzimski_rozgonyi_gonzalez_1997, title={The effect of oxygen on secondary defect formation in MeV self-implanted silicon}, volume={127}, ISSN={["0168-583X"]}, DOI={10.1016/S0168-583X(96)00848-8}, abstractNote={The effects of ion fluence and oxygen concentration on secondary defect formation in MeV self-implanted silicon has been studied for Czochralski (Cz) and float zone (FZ) wafers by means of transmission electron microscopy (TEM) and optical microscopy with bevel polishing/chemical etching. We found that the density, distribution and number of extended defects is strongly dependent upon the oxygen concentration. The dislocation density was found to be up to one order of magnitude lower in FZ wafers. At high ion fluences (∼ 1015 cm−2), secondary defects form in a well-defined band near the ion projected range, Rp. At lower ion fluences, dislocations extend from the defect band to increasingly large depths. For ion fluences approaching the threshold for secondary defect formation (∼ 1014 cm−2), defects are observed from the surface to depths of ⋍ 10 μm, i.e., five times Rp.}, journal={NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION B-BEAM INTERACTIONS WITH MATERIALS AND ATOMS}, author={Brown, RA and Kononchuk, O and Radzimski, Z and Rozgonyi, GA and Gonzalez, F}, year={1997}, month={May}, pages={55–58} }