The present invention concerns methods for producing photovoltaic material and a device able to exploit high energy photons. The photovoltaic material is obtained from a conventional photovoltaic material having a top surface intended to be exposed to photonic radiation, having a built-in P-N junction delimiting an emitter part and a base part and comprising at least one area or region specifically designed, treated or adapted to absorb high energy or energetic photons, located adjacent or near at least one hetero-interface. According to the invention, this material is subjected to treatments resulting in the formation of at least one semiconductor based metamaterial field or region being created, as a transitional region of the or a hetero-interface, in an area located continuous or proximate to the or an absorption area or region for the energetic photons of the photonic radiation impacting said photovoltaic material.

A photovoltaic cell is provided that enables cost reduction and stable operation with a simple configuration and enhances conversion efficiency by a new technology of forming an energy level in a band gap. In the photovoltaic cell, a substrate, a conductive first electrode, an electromotive force layer, a p-type semiconductor layer, and a conductive second electrode are laminated, electromotive force is generated by photoexciting the electron in the band gap of the electromotive force layer by light irradiation, the electromotive force layer is filled with an n-type metal oxide semiconductor of fine particles coated by an insulating coat, a new energy level is formed in a band gap by photoexcited structural change caused by ultraviolet irradiation, and efficient and stable operation can be performed by providing a layer of an n-type metal oxide semiconductor between the first electrode and the electromotive force layer.

An integrated circuit includes a substrate material that includes an epitaxial layer, wherein the substrate material and the epitaxial layer form a first semiconductor material with the epitaxial layer having a first conductivity type. At least one nanowire comprising a second semiconductor material having a second conductivity type doped differently than the first conductivity type of the first semiconductor material forms a junction crossing region with the first semiconductor material. The nanowire and the first semiconductor material form an avalanche photodiode (APD) in the junction crossing region to enable single photon detection. In an alternative configuration, the APD is formed as a p-i-n crossing region where n represents an n-type material, i represents an intrinsic layer, and p represents a p-type material.

Techniques for forming an ohmic back contact for Ag.sub.2ZnSn(S,Se).sub.4 photovoltaic devices. In one aspect, a method for forming a photovoltaic device includes the steps of: depositing a refractory electrode material onto a substrate; depositing a contact material onto the refractory electrode material, wherein the contact material includes a transition metal oxide; forming an absorber layer on the contact material, wherein the absorber layer includes Ag, Zn, Sn, and at least one of S and Se; annealing the absorber layer; forming a buffer layer on the absorber layer; and forming a top electrode on the buffer layer. The refractory electrode material may be Mo, W, Pt, Ti, TiN, FTO, and combinations thereof. The transition metal oxide may be TiO.sub.2, ZnO, SnO, ZnSnO, Ga.sub.2O.sub.3, and combinations thereof. A photovoltaic device is also provided.

Optically sensitive devices include a device comprising a first contact and a second contact, each having a work function, and an optically sensitive material between the first contact and the second contact. The optically sensitive material comprises a p-type semiconductor, and the optically sensitive material has a work function. Circuitry applies a bias voltage between the first contact and the second contact. The optically sensitive material has an electron lifetime that is greater than the electron transit time from the first contact to the second contact when the bias is applied between the first contact and the second contact. The first contact provides injection of electrons and blocking the extraction of holes. The interface between the first contact and the optically sensitive material provides a surface recombination velocity less than 1 cm/s.

A solar cell apparatus according to the embodiment includes a support substrate; a back electrode layer on the support layer; a light absorbing layer on the back electrode layer; a plurality of buffer layers on the light absorbing layer, the plurality of buffer layers having a bandgap gradually increased from a bottom thereof to a top thereof; and a window layer on the buffer layers.

A method of forming a multijunction solar cell comprising at least an upper subcell, a middle subcell, and a lower subcell, the method including forming a first alpha layer over said middle solar subcell using a surfactant and dopant including selenium, the first alpha layer configured to prevent threading dislocations from propagating; forming a metamorphic grading interlayer over and directly adjacent to said first alpha layer; forming a second alpha layer using a surfactant and dopant including selenium over and directly adjacent to said grading interlayer to prevent threading dislocations from propagating; and forming a lower solar subcell over said grading interlayer such that said lower solar subcell is lattice mismatched with respect to said middle solar subcell.

An electronic device includes a trigonal crystal substrate defining a (0001) C-plane. The substrate may comprise Sapphire or other suitable material. A plurality of rhombohedrally aligned SiGe (111)-oriented crystals are disposed on the (0001) C-plane of the crystal substrate. A first region of material is disposed on the rhombohedrally aligned SiGe layer. The first region comprises an intrinsic or doped Si, Ge, or SiGe layer. The first region can be layered between two secondary regions comprising n+doped SiGe or n+doped Ge, whereby the first region collects electrons from the two secondary regions.

Disclosed herein are a solar cell and a method of manufacturing the same. The solar cell module includes a semiconductor substrate, a first passivation film located on a front surface of the semiconductor substrate, a second passivation film located on a rear surface of the semiconductor substrate, a front electric field region located on the first passivation film on the front surface of the semiconductor substrate and being of a same conductivity-type as that of the semiconductor substrate, an emitter region located on the second passivation film on the rear surface of the semiconductor substrate and being of a conductivity-type opposite that of the semiconductor substrate, first electrodes conductively connected to the front electric field region, and second electrode conductively connected to the emitter region.

Methods for producing photovoltaic material and a device able to exploit high energy photons. The photovoltaic material is obtained from a conventional photovoltaic material having a top surface intended to be exposed to photonic radiation, having a built-in P-N junction delimiting an emitter part and a base part and including at least one area or region specifically designed, treated or adapted to absorb high energy or energetic photons, located adjacent or near at least one hetero-interface. This material is subjected to treatments resulting in the formation of at least one semiconductor based metamaterial field or region being created, as a transitional region of the or a hetero-interface, in an area located continuous or proximate to the or an absorption area or region for the energetic photons of the photonic radiation impacting the photovoltaic material.