Provided are photovoltaic devices with polycrystalline type II-VI semiconductor absorber materials including n-type absorber compositions and having p-type hole contact layers are described herein. Methods of treating semiconductor absorber layers and forming hole contact layers are described.

A process for impurification of semiconductor materials, comprising adjacent compensated codoping comprising: (a) providing a multicomponent host material AEGJ . . . ; (b) selecting two impurities Q and X codopants elements under the following scheme: (i) considering the host A and G, impurity Q is the chemical element with atomic number Z.sub.A1 and impurity X is the chemical element with atomic number Z.sub.G+1; or impurity Q is the chemical element with atomic number Z.sub.A+1 and impurity X is the chemical element with atomic number Z.sub.G1; or (ii) considering the host A and G, impurity Q is the chemical element with atomic number Z.sub.A2 and impurity X is the chemical element with atomic number Z.sub.G+2; or impurity Q is the chemical element with atomic number Z.sub.A+2 and impurity X is the chemical element with atomic number Z.sub.G2; or (iii) considering the host A and G, impurity Q is the chemical element with atomic number Z.sub.A1 and impurity X is the chemical element with atomic number Z.sub.G+2; or impurity Q is the chemical element with atomic number Z.sub.A+2 and impurity X is the chemical element with atomic number Z.sub.G1; and (c) performing the host adjacent codoping process with the selected impurities.

This disclosure provides systems, methods, and apparatus related to photodetectors. In one aspect, a photodetector device comprises a substrate, a polycrystalline layer disposed on the substrate, and a first electrode and a second electrode disposed on the polycrystalline layer. The polycrystalline layer comprises nanograins with grain boundaries between the nanograins. The nanograins comprise a semiconductor material. A doping element comprising a halogen is segregated at the grain boundaries. A length of the polycrystalline layer is between and separating the first electrode and the second electrode.

A P-type solar cell comprises a layer stack with: a back electrode, a p-type semiconductor absorber layer disposed on the back electrode, a crystalline cadmium sulfide (CdS) layer disposed on the absorber layer, and a front electrode disposed on the side of the layer stack opposite of the back electrode. The CdS layer has Cu-doping and a layer thickness between 50 and 300 . A method for producing a p-type solar cell comprises: providing a p-type photoactive semiconductor absorber layer, etching the surface of the absorber layer such that crystallographic unevenness and pinholes are reduced, depositing a CdS layer on the absorber layer, with a layer thickness between 50 and 200 , heating at least the CdS layer to recrystallize the CdS layer, and optionally placing on the absorber layer a Cu-containing layer different from the CdS layer, either after etching or after the application of the CdS layer.

A P-type solar cell comprises a layer stack with: a back electrode, a p-type semiconductor absorber layer disposed on the back electrode, a crystalline cadmium sulfide (CdS) layer disposed on the absorber layer, and a front electrode disposed on the side of the layer stack opposite the back electrode. The CdS layer has Cu-doping and a layer thickness between 50 and 300 . A method for producing a p-type solar cell comprises: providing a p-type photoactive semiconductor absorber layer, etching the surface of the absorber layer such that crystallographic unevenness and pinholes are reduced, depositing a CdS layer on the absorber layer, with a layer thickness between 50 and 200 , applying heat to at least the CdS layer to recrystallize the CdS layer, and optionally placing on the absorber layer a Cu-containing layer different from the CdS layer, either after etching or after the application of the CdS layer.

Methods for doping an absorbent layer of a p-n heterojunction in a thin film photovoltaic device are provided. The method can include depositing a window layer on a transparent substrate, where the window layer includes at least one dopant (e.g,. copper). A p-n heterojunction can be formed on the window layer, with the p-n heterojunction including a photovoltaic material (e.g., cadmium telluride) in an absorber layer. The dopant can then be diffused from the window layer into the absorber layer (e.g., via annealing).

Described herein is a method of using the buffer layer of a transparent conductive substrate as a dopant source for the n-type window layer of a photovoltaic device. The dopant source of the buffer layer distributes to the window layer of the photovoltaic device during semiconductor processing. Described herein are also methods of manufacturing embodiments of the substrate structure and photovoltaic device. Disclosed embodiments also describe a photovoltaic module and a photovoltaic structure with a plurality of photovoltaic devices having an embodiment of the substrate structure.

An improved feeder system and method for continuous vapor transport deposition that includes at least two vaporizers couple to a common distributor through an improved seal for separately vaporizing and collecting at least any two vaporizable materials for deposition as a material layer on a substrate. Multiple vaporizer provide redundancy and allow for continuous deposition during vaporizer maintenance and repair.

In one aspect of the present invention, a photovoltaic device is provided. The photovoltaic device includes a window layer and an absorber layer disposed on the window layer, wherein the absorber layer includes a first region and a second region, the first region disposed adjacent to the window layer. The absorber layer further includes a first additive and a second additive, wherein a concentration of the first additive in the first region is greater than a concentration of the first additive in the second region, and wherein a concentration of the second additive in the second region is greater than a concentration of the second additive in the first region. Method of making a photovoltaic device is also provided.

A photovoltaic cell can include a dopant in contact with a semiconductor layer.