Poly silicon layer and structure for forming the same

Abstract

A method of fabricating a poly silicon layer comprising the following steps is provided. First, a substrate is provided and an amorphous silicon layer is formed on the substrate. A patterned metal layer is formed on the amorphous silicon layer. Next, a pulsed rapid thermal annealing process is performed to form a metal silicide between the patterned metal layer and the amorphous silicon layer, wherein the patterned metal layer and the amorphous silicon layer are adopted for conducting thermal energy to the amorphous silicon layer such that the amorphous silicon layer is converted into a polysilicon layer. Finally, the patterned metal layer is removed. A polysilicon layer formed according to the above-mentioned fabrication method is also provided. The grains of the poly silicon layer are spherical in shape.

1 . A poly silicon layer, comprising;
 a substrate; and   a poly silicon layer on the substrate, wherein grains of the polysilicon layer are spherical in shape.   
   
   
       2 . The poly silicon layer according to  claim 1 , wherein a size of the grain is larger than 4000 angstrom. 
   
   
       3 . The poly silicon layer according to  claim 1 , wherein a surface roughness of the poly silicon layer is smaller than 10 angstrom. 
   
   
       4 . The poly silicon layer according to  claim 1 , further comprising a patterned metal layer on the poly silicon layer. 
   
   
       5 . The poly silicon layer according to  claim 4 , wherein a material of the patterned metal layer comprises nickel, cobalt, copper, tantalum, iron or platinum. 
   
   
       6 . A structure for forming a poly silicon layer, comprising;
 a substrate;   an amorphous silicon layer on the substrate;   a patterned metal layer on the amorphous silicon layer; and   a metal silicide between the patterned metal layer and the amorphous silicon layer.   
   
   
       7 . The structure according to  claim 6 , wherein a material of the patterned metal layer comprises nickel, cobalt, copper, tantalum, iron or platinum. 
   
   
       8 . The structure according to  claim 6 , wherein the metal silicide is formed on the surface of the amorphous silicon layer and does not pass through the amorphous silicon layer.