A method for fabricating dislocation-free tensile-strained SiGe films via the oxidation of porous Si substrates

TitleA method for fabricating dislocation-free tensile-strained SiGe films via the oxidation of porous Si substrates
Publication TypeJournal Article
Year of Publication2007
AuthorsKim, J, Li, B, Xie, Y-H
JournalApplied Physics Letters
Volume91
Issue25
Pagination252108
Date Published2007/12/17/
Abstract

A method for fabricating tensile-strained SiGe films via the oxidation of porous Si substrates with thin SiGe overlayers is reported. A 100 nm thick Si(0.77)Ge(0.23) film on a porous Si substrate is fabricated through self-limiting anodization of a heavily doped p-type Si substrate with an epitaxially grown intrinsic Si(0.77)Ge(0.23) overlayer. The pseudomorphic Si(0.77)Ge(0.23) film originally under 0.94% compressive strain on the porous Si substrate becomes completely relaxed by low temperature (500 degrees C) oxidation of the porous Si substrate. Continued oxidation introduces an additional 0.71% tensile strain in the Si(0.77)Ge(0.23) layer without the introduction of dislocations or cracks. (c) 2007 American Institute of Physics.