posed between the doped amorphous silicon layers 55 and 56 is exposed. [0067] Then, it is preferable to practice an oxygen plasma in order to stabilize a surface of the exposed semiconductor 40. [0068] Next, as shown in FIGS. 7a and 7 b, the passivation layer 70 is formed by depositing an inorganic insulating film such as SiNx, or, SiOC or SiOF with a low dielectric, or coating an acryl-based orga