Semiconductor device and method for manufacturing the same

Abstract

In one embodiment, a method for manufacturing a semiconductor device is disclosed. The method can include depositing a first amorphous film having a first impurity, depositing a third amorphous lower-layer film on the first amorphous film, forming microcrystals on the third amorphous lower-layer film, depositing a third amorphous upper-layer film on the third amorphous lower-layer film to cover the microcrystals, depositing a second amorphous film having a second impurity on the third amorphous upper-layer film, and radiating microwaves to crystallize the third amorphous lower-layer film and the third amorphous upper-layer film to form a third crystal layer, and crystallize the first amorphous film and the second amorphous film to form a first crystal layer and a second crystal layer.

1 .- 14 . (canceled) 
     
     
         15 . A semiconductor device comprising:
 a first crystal layer that has a first impurity added thereto;   a third crystal layer that is formed on the first crystal layer; and   a second crystal layer that is formed on the third crystal layer and has a second impurity added thereto,   the third crystal layer containing a metal element.   
     
     
         16 . The semiconductor device according to  claim 15 , wherein the metal element is selected from the group consisting of indium, iridium, titanium, tantalum, cobalt, germanium, platinum, lanthanum, nickel, yttrium, hafnium, zirconium, tin, niobium, barium, strontium, magnesium, and silicon germanium. 
     
     
         17 . The semiconductor device according to  claim 15 , wherein the first crystal layer, the third crystal layer, and the second crystal layer are silicon crystal layers. 
     
     
         18 . A semiconductor device comprising:
 a first crystal lower layer that has a first impurity added thereto;   a second crystal layer that is formed on the first crystal lower layer and has a second impurity added thereto; and   a first crystal upper layer that is formed on the second crystal layer and has the first impurity added thereto,   the second crystal layer including a second crystal lower layer provided on the first crystal lower layer, a second crystal upper layer, and a crystal film placed between the second crystal lower layer and the second crystal upper layer, the crystal film containing a metal element.   
     
     
         19 . The semiconductor device according to  claim 18 , wherein the metal element is selected from the group consisting of indium, iridium, titanium, tantalum, cobalt, germanium, platinum, lanthanum, nickel, yttrium, hafnium, zirconium, tin, niobium, barium, strontium, magnesium, and silicon germanium. 
     
     
         20 . The semiconductor device according to  claim 18 , wherein the first crystal lower layer, the second crystal layer, and the first crystal upper layer are silicon crystal layers.