Polycrystalline silicon semiconductor having an amorphous silicon buffer layer

A semiconductor device having a stacked layer structure on a substrate made of a material different from crystalline silicon and a collecting electrode disposed on said stacked layer structure, said stacked layer structure comprising an amorphous silicon layer having an n- or p-type conductivity on said substrate as a buffer layer and a polycrystalline silicon semiconductor active layer with a multilayered structure disposed on said amorphous silicon layer, said multilayered structure having at least a first polycrystalline silicon layer in non-junction forming contact with said amorphous silicon layer and a second polycrystalline silicon layer having a conductivity type opposite to the conductivity type of said first polycrystalline silicon layer.