Method of manufacturing solar cell

Abstract

A method of manufacturing a solar cell can include forming a silicon oxide film on a semiconductor substrate and successively exposing the silicon oxide film to a temperature in a range of 570° C. to 700° C. to anneal the silicon oxide film.

What is claimed is: 
     
         1 . A method of manufacturing a solar cell, comprising:
 forming a silicon oxide film on a surface of a semiconductor substrate by wet oxidation; and   successively exposing the silicon oxide film to a temperature in a range of 570° C. to 700° C. to anneal the silicon oxide film.   
     
     
         2 . The method according to  claim 1 , wherein, in the successively exposing of the silicon oxide film, the silicon oxide film is annealed at the temperature in the range of 570° C. to 700° C. to form a tunneling layer. 
     
     
         3 . The method according to  claim 1 , wherein, in the forming of the silicon oxide film, a surface of the semiconductor substrate is exposed to a chemical solution made of a liquid oxidizing agent. 
     
     
         4 . The method according to  claim 3 , wherein, the forming of the silicon oxide film is performed at a temperature in a range of 60° C. to 90° C. 
     
     
         5 . The method according to  claim 3 , wherein the liquid oxidizing agent is ozone (O 3 ) or hydrogen peroxide (H 2 O 2 ). 
     
     
         6 . The method according to  claim 1 , wherein a temperature of the forming of the silicon oxide film is lower than the temperature of the successively exposing the silicon oxide film. 
     
     
         7 . The method according to  claim 1 , wherein the semiconductor substrate includes a monocrystalline silicon substrate. 
     
     
         8 . The method according to  claim 1 , further comprising:
 forming a polysilicon layer on the silicon oxide film.   
     
     
         9 . The method according to  claim 8 , wherein the polysilicon layer is formed by using a low pressure chemical vapor deposition (LPCVD). 
     
     
         10 . The method according to  claim 9 , wherein the polycrystalline silicon layer is formed by using the low pressure chemical vapor deposition at a deposition temperature equal to or higher than 600° C. 
     
     
         11 . The method according to  claim 8 , wherein the forming of the polysilicon layer comprises:
 forming an amorphous silicon layer; and   annealing the amorphous silicon layer to form the polysilicon layer.   
     
     
         12 . The method according to  claim 8 , further comprising:
 forming a passivation film on the polysilicon layer; and   forming an electrode connected to the polysilicon layer through penetrating the passivation film.   
     
     
         13 . The method according to  claim 12 , further comprising:
 forming a doped region at the other surface of the semiconductor substrate.   
     
     
         14 . The method according to  claim 13 , wherein the doped region is formed by diffusing a dopant into the semiconductor substrate. 
     
     
         15 . The method according to  claim 13 , wherein the polysilicon layer has a conductive type the same as a conductive type of the semiconductor substrate, and
 wherein the doped region has a conductive type opposite to the conductive type of the semiconductor substrate.