P-type semiconductor material having a wide band gap

Abstract

The production of improved photoresponsive amorphous alloys and devices, such as photovoltaic, photoreceptive devices and the like; having improved wavelength threshold characteristics is made possible by adding one or more band gap increasing elements to the alloys and devices. The increasing element or elements are added at least to a portion of the active photoresponsive regions of amorphous silicon devices. One increasing element is carbon which increases the band gap from that of the materials without the increasing element incorporated therein. Other increasing elements can be used such as nitrogen. The silicon and increasing elements are concurrently combined and deposited as amorphous alloys by vapor deposition, sputtering or glow discharge decomposition. A density of states reducing element allows the band gap increasing element(s) to be added to the alloy to adjust the band gap without reducing the electronic qualities of the alloy. The compensating or altering element(s) can be added during deposition of the alloy or following deposition. The addition of the increasing element(s) to the alloys increases the band gap to a widened utilization width for a particular device to increase the photoabsorption efficiency and to thus enhance the device photoresponse. The band gap increasing element(s) can be added in varying amounts, in discrete layers or in substantially constant amounts in the alloys and devices.