Method for manufacturing thin-film photoelectric conversion device

A method for manufacturing a thin-film photoelectric conversion device, the method comprising:

• a first step of forming a first electrode layer, a photoelectric conversion layer having a first conductive semiconductor layer, a second conductive semiconductor layer, and a third conductive semiconductor layer sequentially laminated thereon, and a second electrode layer sequentially laminated in this order on a translucent insulating substrate, such that adjacent thin-film photoelectric conversion cells are electrically connected in series;
• a second step of isolating a thin-film photoelectric conversion cell into a plurality of thin-film photoelectric conversion cells by forming isolation trenches that reach from a surface of the second electrode layer to the first electrode layer;
• after the second step, a third step of removing a part of sidewalls at an external periphery of the thin-film photoelectric conversion cells positioned at an external peripheral edge of the thin-film photoelectric conversion device, along with an external periphery of the thin-film photoelectric conversion device, and maintaining isolation from the outside;
• and
• a fourth step of modifying into insulation layers by performing an oxidation process on all of the sidewalls of the isolation trenches of the photoelectric conversion layer and all of the sidewalls at the external periphery after the third step.