Patent ID: 8557688

Claim:
A method for fabricating a P-type polycrystalline silicon-germanium structure, comprising: Step S 1 : forming an aluminum layer and an amorphous germanium layer on a P-type monocrystalline silicon substrate in sequence, wherein the aluminum layer is interposed between the P-type monocrystalline silicon substrate and the amorphous germanium layer; Step S 2 : annealing the P-type monocrystalline silicon substrate, wherein the aluminum layer and the amorphous germanium layer undergo annealing at a temperature of 400-650° C.; and Step S 3 : undertaking an aluminum-induced crystallization process in which germanium atoms of the amorphous germanium layer and silicon atoms of the P-type monocrystalline silicon substrate simultaneously pass through the aluminum layer, then the amorphous germanium layer being induced and converted into a P-type polycrystalline silicon-germanium layer between the P-type monocrystalline silicon substrate and the aluminum layer.