@article{shanware_massoud_acker_li_mirabedini_henson_hauser_wortman_1999, title={The effects of Ge content in poly-Si1-xGex gate material on the tunneling barrier in PMOS devices}, volume={48}, ISSN={["0167-9317"]}, DOI={10.1016/s0167-9317(99)00333-0}, abstractNote={The use of SiGe gates in MOSFET technology has promise as a single-gate material for both n- and p-channel MOSFETs. The Ge content in the gate, however, affects the gate energy band diagram. While Ge in the SiGe gate does not affect the conduction-band energy level, it is found to raise the valence-band energy level and reduce the gate bandgap. This change results in an increase in the gate current resulting mainly from the tunneling of electrons from the valence band of the gate in PMOSFETs. This paper reports on the effects of Ge content in SiGe gates on the tunneling characteristics of PMOSFETs.}, number={1-4}, journal={MICROELECTRONIC ENGINEERING}, author={Shanware, A and Massoud, HZ and Acker, A and Li, VZQ and Mirabedini, MR and Henson, K and Hauser, JR and Wortman, JJ}, year={1999}, month={Sep}, pages={39–42} }
 @article{li_mirabedini_vogel_henson_batchelor_wortman_kuehn_1998, title={Effects of Si source gases (SiH4 and Si2H6) on polycrystalline- Si1-xGex deposited on oxide by RTCVD}, volume={1}, number={3}, journal={Electrochemical and Solid State Letters}, author={Li, V. Z. Q. and Mirabedini, M. R. and Vogel, E. and Henson, K. and Batchelor, A. D. and Wortman, J. J. and Kuehn, R. T.}, year={1998}, pages={153–155} }
 @article{heinisch_hornung_linkous_craig_mirabedini_wortman_1998, title={Impact of floating gate dopant concentration and interpoly dielectric processing on tunnel dielectric reliability}, volume={145}, ISSN={["0013-4651"]}, DOI={10.1149/1.1838464}, abstractNote={The influence of gate dopant concentration and thermal budget on the reliability of tunnel dielectric films was studied. Metal oxide semiconductor (MOS) capacitors were furnace annealed after gate formation, floating gate devices were fabricated with interpoly dielectric films either grown by furnace oxidation or deposited by rapid thermal chemical vapor deposition (RTCVD); the latter process is associated with a much lower thermal budget. Ion implanted amorphous silicon was employed for the gate electrodes of the MOS capacitors and for the floating gate layers of the memory devices. The reliability of the dielectrics was evaluated under a constant current stress, and the cycling endurance of the floating gate devices was examined. It was found that tap generation and charge trapping increase with increasing annealing time and increasing dopant concentration, while charge to breakdown (Q bd ) decreases with increasing annealing time. The cycling endurance plot for the floating gate devices revealed little distortion of the threshold voltage window for devices with the low thermal budget RTCVD interpoly dielectric film. Based on this study, a low thermal budget process is preferable for the formation of the interpoly dielectric.}, number={4}, journal={JOURNAL OF THE ELECTROCHEMICAL SOCIETY}, author={Heinisch, HH and Hornung, BE and Linkous, RB and Craig, SA and Mirabedini, MR and Wortman, JJ}, year={1998}, month={Apr}, pages={1351–1355} }
 @article{li_mirabedini_hornung_heinisch_xu_batchelor_maher_wortman_kuehn_1998, title={Structure and properties of rapid thermal chemical vapor deposited polycrystalline silicon-germanium films on SiO2 using Si2H6, GeH4, and B2H6 gases}, volume={83}, ISSN={["0021-8979"]}, DOI={10.1063/1.367404}, abstractNote={Deposition of undoped and in situ boron-doped polycrystalline silicon-germanium (poly-Si1−xGex) films on oxide has been investigated at temperatures below 625 °C and a pressure of 4 Torr in a rapid thermal chemical vapor deposition system. The influences of reactant gases such as Si2H6, SiH4, GeH4, and B2H6 on the nucleation behavior, and structural properties of poly-Si1−xGex films formed on oxide were studied. The experimental results showed that in situ boron-doped or undoped poly-Si1−xGex films can be directly deposited on oxide without an initial Si predeposition layer to provide the necessary nucleation sites on the surface when using Si2H6 as the Si source gas. However, when SiH4 was used as the Si source gas, only in situ boron-doped films can be deposited nonselectively on the oxide without the initial Si predeposition layer, and to deposit undoped poly-Si1−xGex films, Si predeposition is needed, otherwise Si1−xGex islands are formed on the oxide. X-ray diffraction analysis showed that poly-Si1−xGex films deposited using Si2H6, GeH4, and B2H6 gas mixture have three singular peaks corresponding to {311}, {220}, and {111} planes, thus indicating the Si1−xGex alloy is formed. In addition, we found that B2H6 gas has a minor effect on the Ge incorporation into the films but reduces the overall deposition rate.}, number={10}, journal={JOURNAL OF APPLIED PHYSICS}, author={Li, VZQ and Mirabedini, MR and Hornung, BE and Heinisch, HH and Xu, M and Batchelor, D and Maher, DM and Wortman, JJ and Kuehn, RT}, year={1998}, month={May}, pages={5469–5476} }
 @article{li_mirabedini_kuehn_wortman_ozturk_batchelor_christensen_maher_1997, title={Rapid thermal chemical vapor deposition of in situ boron doped polycrystalline silicon germanium films on silicon dioxide for complimentary metal oxide semiconductor applications}, volume={71}, DOI={10.1063/1.120344}, abstractNote={In situ boron-doped polycrystalline Si1−xGex (x>0.4) films have been formed on the thermally grown oxides in a rapid thermal chemical vapor deposition processor using SiH4-GeH4-B2H6-H2 gas system. Our results showed that in situ boron-doped Si1−xGex films can be directly deposited on the oxide surface, in contrast to the rapid thermal deposition of undoped silicon-germanium (Si1−xGex) films on oxides which is a partially selective process and requires a thin silicon film pre-deposition to form a continuous film. For the in situ boron-doped Si1−xGex films, we observed that with the increase of the germane percentage in the gas source, the Ge content and the deposition rate of the film are increased, while its resistivity is decreased down to 0.66 mΩ cm for a Ge content of 73%. Capacitance-voltage characteristics of p-type metal-oxide-semiconductor capacitors with p+-Si1−xGex gates showed negligible polydepletion effect for a 75 Å gate oxide, indicating that a high doping level of boron at the poly-Si1−xGex/oxide interface was achieved.}, number={23}, journal={Applied Physics Letters}, author={Li, V. Z. Q. and Mirabedini, M. R. and Kuehn, R. T. and Wortman, J. J. and Ozturk, M. C. and Batchelor, D. and Christensen, K. and Maher, D. M.}, year={1997}, pages={3388–3390} }