SURFACE-MORPHOLOGY STUDY AND ELECTRICAL-PROPERTIES OF SI1-XCX ON SI GROWN BY LOW-PRESSURE CHEMICAL-VAPOR-DEPOSITION

Si1-xCx alloys were grown on silicon substrates by rapid thermal proce ss/very low pressure chemical vapor deposition (RTP/VLP CVD). The grow th rate is about 0.4 nm/min within the critical thickness and 1.4 nm/m in beyond the critical thickness. Atomic force microscope (AFM) invest igation on different samples indicated that the surface roughness is p roportional to the growth rate and reverse proportional to the mass fl ow ratio of SiH4 to C2H2. This result will provide useful information on the material growth condition. The Raman spectrum study indicated t he strain in Si1-xCx layer and the substitutional C was confirmed by t he observation of the peak at 960 cm(-1). The bandgap of the Si1-xCx l ayer was studied by making Schottky contacts on the Si1-xCx samples. T he barrier height reduction on the strain sample can be attributed to the effect of C incorporation. (C) 1998 Elsevier Science S.A.