Abstract: A photovoltaic device and processes of manufacture are provided that employ particularly configured, textured back reflector structures that maintain a smooth, non-textured surface at the interface between the lowermost doped layer of semiconductor material and the intrinsic, light absorbing layer of nanocrystalline semiconductor material. The back reflector structure provides exhibit both superior short circuit current and a superior fill factor to a photovoltaic device such as those using nanocrystalline semiconductor materials.

Abstract: A tandem photovoltaic device includes at least two photovoltaic cells stacked in an optical and electrical series relationship. At least one of the tandem cells includes a dual function semiconductor layer fabricated from a dual function semiconductor material. This dual function layer is an electronically active constituent of the cell. The dual function layer also is optically active and creates a reflective condition which redirects a portion of the light which has passed through the cell back through the cell's active layers to photo generate additional photocurrent. Use of the dual function material eliminates the need for incorporating separate semiconductor and reflective layers in a photovoltaic device. Further disclosed are exemplary formulations of some dual function materials.

Abstract: A process for the plasma deposition of a layer of a microcrystalline semiconductor material is carried out by energizing a process gas which includes a precursor of the semiconductor material and a diluent with electromagnetic energy so as to create a plasma therefrom. The plasma deposits a layer of the microcrystalline semiconductor material onto the substrate. The concentration of the diluent in the process gas is varied as a function of the thickness of the layer of microcrystalline semiconductor material which has been deposited. Also disclosed is the use of the process for the preparation of an N-I-P type photovoltaic device.

Abstract: A VHF energized plasma deposition process wherein a process gas is decomposed in a plasma so as to deposit the thin film material onto a substrate, is carried out at process gas pressures which are in the range of 0.5-2.0 torr, with substrate temperatures that do not exceed 300° C., and substrate-cathode spacings in the range of 10-50 millimeters. Deposition rates are at least 5 angstroms per second. The present method provides for the high speed deposition of semiconductor materials having a quality at least equivalent to materials produced at a much lower deposition rate.

Abstract: A thin film, hydrogenated, silicon based semiconductor alloy material is produced by a VHF energized plasma deposition process wherein a process gas is decomposed in a plasma so as to deposit the thin film material onto a substrate. The process is carried out at process gas pressures which are in the range of 0.5-2.0 torr, with substrate temperatures that do not exceed 300° C., and substrate-cathode spacings in the range of 10-50 millimeters. Deposition rates are at least 5 angstroms per second. Also disclosed are photovoltaic devices which include the semiconductor material.

Abstract: A semiconductor device of p-i-n type configuration includes a p layer which is comprised of a p-doped semiconductor material, an n layer comprised of an n-doped semiconductor material and an i layer comprised of a substantially intrinsic, nanocrystalline semiconductor material interposed therebetween. The crystalline volume in the i layer decreases as the thickness of said layer increases from its interface with the n layer to its interface with the p layer. The grain size of the substantially intrinsic nanocrystalline semiconductor material may also decrease as the thickness of the i layer increases from its interface with the n layer to its interface with the p layer. The volume of regions of intermediate range order in a portion of the i layer commencing at the interface of the i layer and the p layer, and comprising no more than 50% of the thickness thereof, is greater than is the volume of regions of intermediate range order in the remainder of the i layer.

Abstract: A process for the plasma deposition of a layer of a microcrystalline semiconductor material is carried out by energizing a process gas which includes a precursor of the semiconductor material and a diluent with electromagnetic energy so as to create a plasma therefrom. The plasma deposits a layer of the microcrystalline semiconductor material onto the substrate. The concentration of the diluent in the process gas is varied as a function of the thickness of the layer of microcrystalline semiconductor material which has been deposited. Also disclosed is the use of the process for the preparation of an N-I-P type photovoltaic device.