Application Of Cl-2 For Low Temperature Etch And Epitaxy

In this work, two most typical applications of Cl-2 etch relevant for sub-10 nm CMOS device production, namely sacrificial etch and selective deposition are presented. It is shown that Si0.7Ge0.3 sacrificial etch with Cl-2 is possible in the temperature range of 350 degrees C-400 degrees C when He is used as a carrier gas. This temperature range can be further lowered when He is substituted with N-2. Use of N-2 also allows Si etch at very low temperatures (similar to 400 degrees C) which are not accessible for etching with HCl and potentially can be used for sacrificial etch of Si and Si-based epitaxial selective growth processes. Furthermore, a combination of Cl-2 with high order Si and Ge precursors allowed development of cyclic selective epitaxial processes at temperatures as low as 400 degrees C with active dopant concentrations of similar to 1 x 10(20) cm(-3) for Si0.7Ge0.3:B and similar to 3 x 10(19) cm(-3) for Si0.7Ge0.3:P.