Patent ID: 8044296

Claim:
A photovoltaic device comprising: a substrate having a first insulating surface; an insulating layer having a second insulating surface, wherein the second insulating surface is formed in contact with the first insulating surface; a first electrode formed over the insulating layer; a single crystal semiconductor layer formed over the first electrode, wherein the single crystal semiconductor layer comprises hydrogen and halogen; a protection film formed over the single crystal semiconductor layer, and a second electrode formed over the protection film, wherein the single crystal semiconductor layer comprises: a first impurity layer comprising a first impurity; a second impurity layer formed between the first impurity layer and the protection film, comprising a second impurity, wherein the protection film comprises the second impurity, wherein a first conductivity type of the first impurity is different from a second conductivity type of the second impurity, wherein the second impurity layer comprises: a first region; and a second region formed between the first region and the second electrode, wherein a concentration of halogen in the second region is higher than that of the first region, and wherein the second insulating surface is able to form a hydrophilic surface.