Si 1Ϫx Ge x /Si heterostructures are useful for numerous device applications where device performance is improved by band offsets and/or increased carrier mobility. The use of selective epitaxial growth for the implementation of Si 1Ϫx Ge x has some advantages compared to a nonselective growth process. However, some issues such as thickness nonuniformity ͑microloading on a micrometer scale and gas depletion on a wafer scale͒ and facet formation must be solved. In this paper, we give a detailed overview of our selective Si 1Ϫx Ge x growth process in a standard production-oriented chemical vapor deposition system for Ge contents between 0 and 32%. Our process allows layer deposition with no pattern dependence of the growth rate and Ge content ͑no microloading͒ and with a wafer scale layer nonuniformity that is better than the accuracy of the measurement techniques (ϳ2%). Facet formation was avoided by choosing the correct growth conditions and by preventing lateral growth over the mask material. Selective epitaxial layers did not show a degradation of photoluminescence characteristics. The layer quality is further demonstrated by the performance of Si 1Ϫx Ge x heterojunction bipolar transistors ͑0.35 and 0.25 m technology͒, and p-type Si 1Ϫx Ge x heterojunction metal oxide semiconductor devices ͑effective gate length down to 70 nm͒.

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