SELECTIVE EPITAXIAL-GROWTH OF SI1-XGEX SI STRAINED-LAYERS IN A TUBULAR HOT-WALL LOW-PRESSURE CHEMICAL-VAPOR-DEPOSITION SYSTEM/

Selective epitaxial growth (SEG) of SiGe on patterned-oxide silicon su bstrates, using a tubular hot-wall low pressure chemical vapor deposit ion (LPCVD) system, has been demonstrated. This conventional LPCVD sys tem was proposed as a low cost alternative for SiGe epitaxial growth. Dichlorosilane (SiH2Cl2) and germane (GeH4) were used as the reactant gases with hydrogen as a carrier gas, with no addition of HCl needed t o achieve selectivity in quality epitaxial growth of SiGe. Nomarski mi croscopy showed good selectivity with no nucleation occurring on the S iO2 areas. A low defect silicon buffei layer grown under SEG condition s was key in obtaining high-quality growth. Cross-sectional transmissi on electron microscopy showed that the SiGe strained layers grown at 7 00 degrees C, 750 degrees C, and 800 degrees C were of high quality. ( C) 1997 American Vacuum Society.