@article{oneil_ozturk_violette_batchelor_christensen_maher_1997, title={Optimization of process conditions for selective silicon epitaxy using disilane, hydrogen, and chlorine}, volume={144}, ISSN={["0013-4651"]}, DOI={10.1149/1.1838003}, abstractNote={We have previously reported a process for low temperature selective silicon epitaxy using Si 2 H 6 , H 2 , and Cl 2 in an ultrahigh vacuum rapid thermal chemical vapor deposition reactor. Selective deposition implies that growth occurs on the Si surface but not on any of the surrounding insulator surfaces. Using this method and process chemistry, the level of Cl species required to maintain adequate selectivity has been greatly reduced in comparison to SiH 2 Cl 3 -based, conventional CVD approaches. In this report, we have extended upon the previous work and provide information regarding the selectivity of the silicon deposition process to variations in the growth conditions. We have investigated the selectivity of the process to variations in disilane flow/partial pressure, growth temperature, and system contamination. We demonstrate that increases in either the Si 2 H 6 partial pressure or flow rate, the process temperature, or the source contamination levels can lead to selectivity degradation. In regard to the structural quality of the selective epitaxial layers, we have observed epitaxial defects that have appeared to be a strong function of two basic conditions: the contamination level of the process and the chlorine flow rate or chlorine partial pressure. Overall, the results in this study indicate several process conditions that can inhibit the quality of a selective silicon deposition process developed for single-wafer manufacturing.}, number={9}, journal={JOURNAL OF THE ELECTROCHEMICAL SOCIETY}, author={ONeil, PA and Ozturk, MC and Violette, KE and Batchelor, D and Christensen, K and Maher, DM}, year={1997}, month={Sep}, pages={3309–3315} }
 @article{sun_bartholomew_bellur_oneil_srivastava_violette_ozturk_osburn_masnari_1996, title={Sub-half micron elevated source/drain NMOSFETs by low temperature selective epitaxial deposition}, volume={429}, ISBN={["1-55899-332-0"]}, ISSN={["0272-9172"]}, DOI={10.1557/proc-429-343}, abstractNote={AbstractIn this paper we report the first NMOSFETs with elevated S/D selectively deposited by ultra high vacuum rapid thermal chemical vapor deposition (UHV-RTCVD). The deposition process included an in-situ vacuum prebake (750 °C for 10 sec) followed by selective epitaxial growth (SEG) at 800 °C. Si2H6 was used as the silicon gas source instead of the more commonly used SiH4 and SiH2Cl2 in order to achieve high growth rates at low pressure. To prevent nucleation from occurring on insulator surfaces during growth, an etching mechanism was introduced by the addition of Cl2. The gases included 100 sccm of 10% Si2H6 in H2 and 2 sccm of Cl2 at a process pressure of 24 mTorr. An epitaxial growth rate of 160 nm/min has been achieved. The final epi thickness was around 0.1 μm. The S/D junctions were formed via ion implantation into the epi. The subsequent RTA (10 sec at 950 °C) resulted in an effective junction depth about 75 nm beneath the starting Si substrate. Process and device simulations reveal the importance of maintaining a shallow LDD junction for deep submicron devices by using low temperature selective deposition. MOSFETs exhibit good subthreshold characteristics with subthreshold swing of 86 mV/dec at a drain bias of 2.5 V, and threshold variations due to charge sharing and drain-induced-barrierlowering (DIBL) were moderate for Leff down to 0.35 μm. The gate-induced junction leakage current is below 2 pA/μm at a bias of 2.5 V.}, journal={RAPID THERMAL AND INTEGRATED PROCESSING V}, author={Sun, J and Bartholomew, RF and Bellur, K and ONeil, PA and Srivastava, A and Violette, KE and Ozturk, MC and Osburn, CM and Masnari, NA}, year={1996}, pages={343–347} }