Patent ID: 7199303

Claim:
An optical energy conversion apparatus comprising: a substrate; an adhesive layer coated on said substrate; a barrier layer formed on said adhesive layer; a first electrode layer formed on said barrier layer; a reflecting film form on said first electrode layer; a first impurity doped semiconductor layer, formed on said reflecting film, said first impurity doped semiconductor layer being of a semiconductor material admixed with a first impurity; an optically active layer, formed on said first impurity doped semiconductor layer, said optically active semiconductor layer being of a hydrogen-containing amorphous semiconductor material; a second impurity doped semiconductor layer, admixed with a second impurity and formed on said optically active semiconductor layer, said second impurity doped semiconductor layer being of a polycrystallized semiconductor material lower in hydrogen concentration than the material of said optically active semiconductor layer; and a second electrode layer provided on said second impurity doped semiconductor layer; wherein the average crystal grain size of said second impurity doped semiconductor layer is decreased stepwise in a direction proceeding from the surface of the second impurity doped semiconductor layer towards said substrate.