Techniques for achieving band gap grading in CZTS/Se absorber materials are provided. In one aspect, a method for creating band gap grading in a CZTS/Se absorber layer includes the steps of: providing a reservoir material containing Si or Ge; forming the CZTS/Se absorber layer on the reservoir material; and annealing the reservoir material and the CZTS/Se absorber layer under conditions sufficient to diffuse Si or Ge atoms from the reservoir material into the CZTS/Se absorber layer with a concentration gradient to create band gap grading in the CZTS/Se absorber layer. A photovoltaic device and method of forming the photovoltaic device are also provided.

The present disclosure provides systems, processes, articles of manufacture, and compositions that relate to core/shell semiconductor nanowires. Specifically, the disclosure provides a novel semiconductor material, CdSe/ZnS core/shell nanowires, as well as a method of preparation thereof. The disclosure also provides a new continuous flow method of preparing core/shell nanowires, including CdSe/CdS core/shell nanowire and CdSe/ZnS core/shell nanowires.

A method for producing an ohmic contact for an electronic part, wherein a layer consisting of a semiconductor is applied to a substrate is disclosed. A surface to be contacted of the applied semiconductor is wet-chemically etched, which is rinsed with radicals. An electrical conductor or a semiconductor is applied to the surface rinsed with radicals. An electronic component having several semiconductor layers on a substrate is also disclosed. A top layer on the one or more semiconductor layers is applied to the substrate. The top layer consists of an electrically non-conductive dielectric having an access through the top layer to a semiconductor layer, wherein adjacent semiconductor layers consist of different II-VI semiconductors. The access is at least partially filled with a II-VI semiconductor. A metallic contact applied to the II-VI semiconductor extends to the outer side of the top layer or projects outwardly relative to the top layer.

A hybrid vapor phase-solution phase CZT(S,Se) growth technique is provided. In one aspect, a method of forming a kesterite absorber material on a substrate includes the steps of: depositing a layer of a first kesterite material on the substrate using a vapor phase deposition process, wherein the first kesterite material includes Cu, Zn, Sn, and at least one of S and Se; annealing the first kesterite material to crystallize the first kesterite material; and depositing a layer of a second kesterite material on a side of the first kesterite material opposite the substrate using a solution phase deposition process, wherein the second kesterite material includes Cu, Zn, Sn, and at least one of S and Se, wherein the first kesterite material and the second kesterite material form a multi-layer stack of the absorber material on the substrate. A photovoltaic device and method of formation thereof are also provided.

Disclosed herein are compositions and methods for making polycrystalline thin films having very large grains sizes and exhibiting improved properties over existing thin films.

A thin film structure according to various example embodiments includes a first buffer layer, a transition metal dichalcogenide layer on the first buffer layer, and a second buffer layer on the transition metal dichalcogenide layer, wherein the second buffer layer includes same chalcogen element as a chalcogen element included in the transition metal dichalcogenide layer.

A photovoltaic device is presented. The photovoltaic device includes a layer stack; and an absorber layer is disposed on the layer stack. The absorber layer comprises selenium, wherein an atomic concentration of selenium varies across a thickness of the absorber layer. The photovoltaic device is substantially free of a cadmium sulfide layer.

A photovoltaic device is presented. The photovoltaic device includes a layer stack; and an absorber layer is disposed on the layer stack. The absorber layer comprises selenium, wherein an atomic concentration of selenium varies across a thickness of the absorber layer. The photovoltaic device is substantially free of a cadmium sulfide layer.