Enhancement of short-circuit current by use of wide bandgap n-layers in p-i-n amorphous silicon photovoltaic cells

摘要

A photovoltaic cell (10) that includes a transparent substrate (12), a front conductive layer (14) formed on the substrate, a p-type layer (16) formed on the front conductive layer, an i-layer (18) of amorphous silicon formed on the p-layer, a wide bandgap n-type layer (20) formed on the i-layer and a back contact layer (25) formed on the n-type structure. The wide bandgap n-type layer (20) may be an n-type sandwich structure includes first, second and third n-layers (21,22,23) alternatingly formed on one another. The first n-layer (21) is formed on the i-layer, the second n-layer (22) is formed on the first n-layer (21), and the n-layer (23) is formed on the second n-layer (22). The second n-layer (22) has an optical bandgap wider than the optical bandgap of the first and second n-type layers (21,23).