Photoelectric conversion device

A photoelectric conversion device comprising:

• a first electrode;
• a second electrode;
• a crystalline silicon substrate having one conductivity type between the first electrode and the second electrode;
• a first silicon semiconductor layer having a conductivity type opposite to that of the crystalline silicon substrate between the crystalline silicon substrate and the first electrode;
• a light-transmitting conductive film between the first silicon semiconductor layer and the first electrode;
• and
• a second silicon semiconductor layer having the same conductivity type as the crystalline silicon substrate between the crystalline silicon substrate and the second electrode,
• wherein the second silicon semiconductor layer comprises a first region, a second region over the first region, and a third region over the second region,
• wherein the second silicon semiconductor layer comprises an impurity element imparting a conductivity type,
• wherein a concentration of the impurity element is constant in the third region,
• wherein a concentration of the impurity element in the second region monotonically increases in a film thickness direction from a third region side to a first region side,
• wherein a concentration of the impurity element is constant in the first region, and
• wherein the second silicon semiconductor layer is in contact with the second electrode.

A photoelectric conversion device comprising:

• a first electrode;
• a second electrode;
• a crystalline silicon substrate having one conductivity type between the first electrode and the second electrode;
• a first silicon semiconductor layer having a conductivity type opposite to that of the crystalline silicon substrate between the crystalline silicon substrate and the first electrode;
• a light-transmitting conductive film between the first silicon semiconductor layer and the first electrode;
• and
• a second silicon semiconductor layer having the same conductivity type as the crystalline silicon substrate between the crystalline silicon substrate and the second electrode,
• wherein the first silicon semiconductor layer comprises a first region, a second region under the first region, and a third region under the second region,
• wherein the first silicon semiconductor layer comprises a first impurity element imparting a conductivity type,
• wherein a concentration of the first impurity element is constant in the third region,
• wherein a concentration of the first impurity element in the second region monotonically increases in a film thickness direction from a third region side to a first region side,
• wherein a concentration of the first impurity element is constant in the first region
• wherein the second silicon semiconductor layer comprises a fourth region, a fifth region over the fourth region, and a sixth region over the fifth region,
• wherein the second silicon semiconductor layer comprises a second impurity element imparting a conductivity type,
• wherein a concentration of the second impurity element is constant in the sixth region,
• wherein a concentration of the second impurity element in the second region monotonically increases in a film thickness direction from a sixth region side to a fourth region side,
• wherein a concentration of the second impurity element is constant in the fourth region, and
• wherein the second silicon semiconductor layer is in contact with the second electrode.