Reducing grain-boundary effects in polycrystalline silicon solar cells

Solar-cell structures were prepared by depositing successively p- and n+-type silicon layers on low-resistivity p-type polycrystalline silicon substrates. The characteristics of the solar cells are limited predominately by the grain boundaries in the deposited p layer. The effects of grain boundaries can be reduced by increasing the dopant concentration in the p layer, and solar cells of lower series resistance and higher conversion efficiency have been obtained.