abstract |
Epitaxial and polycrystalline layers of silicon and silicon-germanium alloys are selectively grown on a semiconductor substrate or wafer by forming over the wafer a thin film masking layer of an oxide of an element selected from scandium, yttrium, lanthanum, cerium, praseodymium, neodymium, samarium, europium, gadolinium, terbium, dysprosium, holmium, erbium, thulium, ytterbium, and lutetium; and then growing the epitaxial layer over the wafer at temperatures below 650° C. The epitaxial and polycrystalline layers do not grow on the masking layer. The invention overcomes the problem of forming epitaxial layers at temperatures above 650° C. by providing a lower temperature process. |