US Patent 7303786 Method of forming a polysilicon layer

In a method of forming a polysilicon layer on a substrate, a first embodiment comprises: doping inert gas into the substrate to form a plurality of pores in the substrate; depositing a buffer later on the substrate; depositing an amorphous silicon layer on the buffer layer; and heating the amorphous silicon layer to convert the amorphous silicon layer into a polysilicon layer. A second embodiment comprises: depositing a first buffer layer on a substrate; doping inert gas into the first buffer layer to form a plurality of pores in the first buffer layer; depositing a second buffer layer on the first buffer layer; depositing an amorphous silicon layer on the second buffer layer; and heating the amorphous silicon layer to convert the amorphous silicon layer into a polysilicon layer.