SINGLE-WAFER SI AND SIGE PROCESSES FOR ADVANCED ULSI TECHNOLOGIES

Low thermal budget as well as new industrially processable materials w ill be key issues in future advanced CMOS (less than or equal to 0.18 mu m) and bipolar technologies. Low-temperature deposition of Si and S i1-xGex (referred to as SiGe hereafter) has been performed using an in dustrial, 200 mm, single-wafer CVD module operating at reduced pressur e. Epitaxial Si and heteroepitaxial SiGe growth has been studied for b uried channel applications in CMOS devices or as a base for heterojunc tion bipolar transistors (HBTs), as well as polycrystalline SiGe with a high Ge content as a potential alternative material for poly gate st acks. The dependence of the deposition rate on the filling ratio and w indow size, and its evolution with the addition of HCl to the gas mixt ure is investigated for selectively grown SiGe layers. The pattern dep endence of the Ge content is also presented. Preliminary results on po ly-SiGe films with Ge contents up to 100% are shown and discussed.