@article{alptekin_ozturk_misra_cho_kim_chopra_2009, title={Erbium Silicide Formation on Si1-xCx Epitaxial Layers}, volume={156}, ISSN={["1945-7111"]}, DOI={10.1149/1.3097189}, abstractNote={Erbium silicide (ErSi 2-x ) formation was investigated on Si 1-x C x epitaxial layers grown on Si substrates. Substitutional carbon incorporation in the epitaxial layers was in the range of 0.6-1.6%. The silicide films were formed by rapid thermal annealing of sputter-deposited erbium layers in the temperature range of 350-700°C. The sheet resistance of the silicide films formed on Si 1-x C x epitaxial layers was found to be equal to or less than the sheet resistance of the films formed on Si epitaxial layers. At 600°C, an average resistivity of 114 ± 4 μΩ cm was obtained. The silicide grains were found to be epitaxially aligned to the substrate along the (100) orientation, regardless of the carbon concentration in the underlying epitaxial layer. Compositional analysis of the films indicated carbon accumulation at the ErSi 2-x /Si 1-x C x interface with no carbon incorporation in the silicide. The films formed on Si 1-x C x epitaxial layers exhibited a smooth interface/surface morphology free of pinholes, contrary to the silicides formed on Si. The root-mean-square surface roughness was found to be less than 1.5 nm, which was found to be the case with both substitutional and interstitial incorporation of carbon atoms in the epitaxial layer.}, number={5}, journal={JOURNAL OF THE ELECTROCHEMICAL SOCIETY}, author={Alptekin, Emre and Ozturk, Mehmet C. and Misra, Veena and Cho, Yonah and Kim, Yihwan and Chopra, Saurabh}, year={2009}, pages={H378–H383} }
 @misc{ozturk_misra_chopra_2007, title={Methods of fabricating strained semiconductor-on-insulator field-effect transistors and related devices}, volume={7,211,458}, number={2007 May 1}, publisher={Washington, DC: U.S. Patent and Trademark Office}, author={Ozturk, M. and Misra, V. and Chopra, S.}, year={2007} }
 @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{chopra_ozturk_misra_ren_mcneil_2007, title={The effects of nickel germanosilicide contacts on the biaxial compressive stress in thin epitaxial silicon-germanium alloys on silicon}, volume={91}, ISSN={["1077-3118"]}, DOI={10.1063/1.2795346}, abstractNote={When a thin Si1−xGex epitaxial layer is grown on Si, it is under biaxial compression. In this letter, it is shown that a nickel germanosilicide (NiSi1−xGex) layer formed on Si1−xGex can significantly reduce the in-plane compressive strain in Si1−xGex. It is proposed that the observed reduction is due to the biaxial tensile stress applied by the NiSi1−xGex layer. Because the Si1−xGex bandgap is a strong function of the strain, this is expected to have a strong impact on the metal-semiconductor barrier height and the contact resistivity of the interface if the metal Fermi level is pinned near the Si1−xGex midgap.}, number={14}, journal={APPLIED PHYSICS LETTERS}, author={Chopra, Saurabh and Ozturk, Mehmet C. and Misra, Veena and Ren, Zhongqiao and McNeil, L. E.}, year={2007}, month={Oct} }
 @article{chopra_ozturk_misra_mcguire_mcneil_2006, title={Analysis of boron strain compensation in silicon-germanium alloys by Raman spectroscopy}, volume={88}, ISSN={["1077-3118"]}, DOI={10.1063/1.2205752}, abstractNote={The impact of heavy boron doping on the biaxial compressive strain in Si1−xGex layers grown on Si has been investigated using Raman spectroscopy and theoretical calculations. It is shown that one boron atom is sufficient to compensate the strain due to approximately 6.9 Ge atoms. This effect is appreciably large for boron concentrations as low as 1%, typical for applications, which employ heavily boron doped layers. Using strain compensation, the Ge content can be substantially increased without increasing the stored strain energy. This phenomenon can be useful in applications, which require low-resistivity p-type strained Si1−xGex layers with high Ge content.}, number={20}, journal={APPLIED PHYSICS LETTERS}, author={Chopra, Saurabh and Ozturk, Mehmet C. and Misra, Veena and McGuire, Kris and McNeil, Laurie E.}, year={2006}, month={May} }
 @misc{rao_chopra_2006, title={Carbon nanotube based resonant-circuit sensor}, volume={6,997,039}, number={2006 Feb. 14}, publisher={Washington, DC: U.S. Patent and Trademark Office}, author={Rao, A. M. and Chopra, S.}, year={2006} }
 @article{chopra_ozturk_misra_mcguire_mcneil_2006, title={Critical thickness of heavily boron-doped silicon-germanium alloys}, volume={89}, ISSN={["1077-3118"]}, DOI={10.1063/1.2374870}, abstractNote={In this work, the effect of boron concentration on the critical thickness of heavily boron doped Si1−xGex alloys (Si1−x−yGexBy) has been studied using Raman spectroscopy. The experimental results indicate that while boron decreases the stored strain energy, it can substantially increase the critical thickness for a given Ge concentration. The Si1−x−yGexBy critical thickness was calculated using two different models based on energy balance and kinetic considerations. The results show that the kinetic model provides a good estimate for the Si1−x−yGexBy critical thickness.}, number={20}, journal={APPLIED PHYSICS LETTERS}, author={Chopra, Saurabh and Ozturk, Mehmet C. and Misra, Veena and McGuire, Kris and McNeil, L. E.}, year={2006}, month={Nov} }