Patent ID: 8349643

Claim:
A method of manufacturing a photovoltaic device comprising: forming a substantially intrinsic first amorphous silicon layer on a surface of a crystalline silicon layer with conductivity; forming a second amorphous silicon layer on the first amorphous silicon layer, wherein the forming of the first amorphous silicon layer includes performing a CVD (chemical vapor deposition) method; and the CVD method includes introducing CO 2 gas with an ambient gas, wherein introducing CO 2 gas comprises controlling a volume of the CO 2 gas to obtain an oxygen concentration of a portion of the first amorphous silicon layer in the vicinity of an interface with the crystalline silicon layer equal to or below 10 20 cm −3 , wherein the oxygen concentration in the portion of the first amorphous silicon layer is lower than that of the oxygen concentration at the interface with the crystalline silicon layer, wherein an oxygen concentration profile of a portion of the first amorphous silicon layer on the crystalline silicon layer side of the first amorphous silicon layer includes a higher value in the vicinity of the interface with the crystalline silicon layer and a lower value deeper from the vicinity of the interface, and wherein the first amorphous silicon layer includes a portion on the second amorphous silicon layer side whose oxygen concentration is more than or equal to 10 20 cm −3 .