Photoelectric conversion device and manufacturing method thereof

A photoelectric conversion device, comprising:

• a semiconductor substrate comprising a front side and a back side;
• a protective layer formed on the front side of the semiconductor substrate;
• a first non-single crystalline semiconductor layer formed on a first portion of the back side of the semiconductor substrate, the first non-single crystalline semiconductor layer being an intrinsic semiconductor layer;
• a first conductive layer comprising a first impurity formed on a back side of the first non-single crystalline semiconductor layer;
• a second non-single crystalline semiconductor layer comprising a second impurity formed on a second portion of the back side of the semiconductor substrate;
• a second conductive layer comprising the first impurity and the second impurity formed on a back side of the second non-single crystalline semiconductor layer,
• wherein a concentration of the first impurity is greater than or equal to that of the second impurity in the second conductive layer,
• wherein:
• the first impurity comprises a group 3 or 5 element, the second impurity comprises a group 3 or 5 element, and the first and second impurities comprise different group elements than each other, and
• the first conductive layer and the second conductive layer include polycrystalline or amorphous silicon.