TECHNOLOGY FOCUS - INORGANIC CHEMISTRY - Preferred Method: The etching and removing step of intrinsic type amorphous semiconductor layer, n-type amorphous semiconductor layer (n) and transparent conductive oxide film of the n-doped region, comprises applying etching paste on the transparent conductive oxide film of the n-doped region, removing the transparent conductive oxide film applied with etching paste by heat treating the substrate, and performing wet etching of the p-type amorphous semiconductor layer and intrinsic type amorphous semiconductor layer of the n-doped region using the transparent conductive oxide film remaining on the p-doped region as etch mask. The method comprises removing etching paste remaining on p-type amorphous semiconductor layer, intrinsic type amorphous semiconductor layers and n-type amorphous semiconductor layer by wet etching, and etching paste remaining on n-type amorphous semiconductor layer, intrinsic type amorphous semiconductor layer and n-type amorphous semiconductor layer by wet etching. The etching and removing step of the intrinsic type amorphous semiconductor layer, n-type amorphous semiconductor layer and the transparent conductive oxide film of the p-doped region, comprises applying etching paste on the transparent conductive oxide film of the p-doped region, removing the transparent conductive oxide film applied with etching paste by heat treating the substrate, and performing wet etching of the n-type amorphous semiconductor layer and intrinsic type amorphous semiconductor layers of the p-doped region using the transparent conductive oxide film remaining on the p-doped region as etch mask.    TECHNOLOGY FOCUS - INORGANIC CHEMISTRY - Preferred Components: The etchant used in wet etching is alkaline aqueous solution, preferably potassium hydroxide, sodium hydroxide, lithium hydroxide, rubidium hydroxide or cesium hydroxide, or acid aqueous solution, preferably hydrogen fluoride, nitric acid, hydrochloric acid, sulfuric acid or acetic acid.