An optical device useful for spatial light modulation. The device comprises: a semiconductor layer having a first surface and a second surface, the semiconductor having an electric field-dependent resonance wavelength; a first electrode electrically connected to the semiconductor layer; a first insulating layer adjacent to the first surface of the semiconductor layer, and a second insulating layer adjacent to the second surface of the semiconducting layer, the first and the second insulating layers each being optically transparent at the resonance wavelength; a first group of at least one gate electrodes disposed adjacent to the first insulating layer, and a second group of at least one gate electrodes disposed adjacent to the second insulating layer, each gate electrode being at least 80% optically transparent at the resonance wavelength; wherein the first and the second groups of gate electrodes, taken together, form at least two regions in the semiconductor layer, an electrostatic field in each of the at least two regions being independently controllable by application of voltage to the first and the second groups of gate electrodes, the at least two regions abutting each other along at least one boundary.

A method for forming a back contact on an absorber layer in a photovoltaic device includes forming a two dimensional material on a first substrate. An absorber layer including CuZnSnS(Se) (CZTSSe) is grown over the first substrate on the two dimensional material. A buffer layer is grown on the absorber layer on a side opposite the two dimensional material. The absorber layer is exfoliated from the two dimensional material to remove the first substrate from a backside of the absorber layer opposite the buffer layer. A back contact is deposited on the absorber layer.

A PV module includes a transparent substrate, a first solar cell unit, a crystalline silicon solar cell, and a spacer. The first solar cell unit is between the transparent substrate and the crystalline silicon solar cell, and the first solar cell unit includes a first electrode, a second electrode, and a I-III-VI semiconductor layer between the first electrode and the second electrode. The I-III-VI semiconductor layer includes at least gallium (Ga) and sulfur (S), and the energy gap thereof is more than that of crystalline silicon. Moreover, the crystalline silicon solar cell and the first solar cell unit are separated by the spacer.

A method for fabricating an optically transparent conductor including depositing a plurality of metal nanowires on a substrate, annealing or illuminating the plurality of metal nanowires to thermally or optically fuse nanowire junctions between metal nanowires to form a metal nanowire network, disposing a graphene layer over the metal nanowire network to form a nanohybrid layer comprising the graphene layer and the metal nanowire network, depositing a dielectric passivation layer over the nanohybrid layer, patterning the dielectric passivation layer using lithography, printing, or any other method of patterning to define an area for the optically transparent conductor, and etching the patterned dielectric passivation layer to define the optically transparent conductor.

Various embodiment include optical and optoelectronic devices and methods of making same. Under one aspect, an optical device includes an integrated circuit having an array of conductive regions, and an optically sensitive material over at least a portion of the integrated circuit and in electrical communication with at least one conductive region of the array of conductive regions. Under another aspect, a film includes a network of fused nanocrystals, the nanocrystals having a core and an outer surface, wherein the core of at least a portion of the fused nanocrystals is in direct physical contact and electrical communication with the core of at least one adjacent fused nanocrystal, and wherein the film has substantially no defect states in the regions where the cores of the nanocrystals are fused. Additional devices and methods are described.

A photovoltaic device including a single junction solar cell provided by an absorption layer of a type IV semiconductor material having a first conductivity, and an emitter layer of a type III-V semiconductor material having a second conductivity, wherein the type III-V semiconductor material has a thickness that is no greater than 50 nm.

In one embodiment, harmful solar cell polarization is prevented or minimized by providing a conductive path that bleeds charge from a front side of a solar cell to the bulk of a wafer. The conductive path may include patterned holes in a dielectric passivation layer, a conductive anti-reflective coating, or layers of conductive material formed on the top or bottom surface of an anti-reflective coating, for example. Harmful solar cell polarization may also be prevented by biasing a region of a solar cell module on the front side of the solar cell.

One embodiment of the present invention can provide a system for fabrication of a photovoltaic structure. The system can include a physical vapor deposition tool configured to sequentially deposit a transparent conductive oxide layer and a metallic layer on an emitter layer formed in a first surface of a Si substrate, without requiring the Si substrate to be removed from the physical vapor deposition tool after depositing the transparent conductive oxide layer. The system can further include an electroplating tool configured to plate a metallic grid on the metallic layer and a thermal annealing tool configured to anneal the transparent conductive oxide layer.

Disclosed are an electrode structure and a method for producing an electrode. The method includes disposing first and second wires on a substrate, and bonding the first and second wires to each other. The electrode structure includes a substrate, a first wire disposed on the substrate, and a second wire disposed on the substrate. The first wire crosses the second wire, and the first and second wires are bonded to each other.

The present invention relates to a transparent compound semiconductor and to a production method therefor, and is adapted to provide a transparent compound semiconductor of high stability and charge mobility while being transparent. The transparent compound semiconductor according to the present invention has a composition of Ba.sub.1XLa.sub.XSnO.sub.3 (0<x<0.1) and has a charge mobility of at least 10 cm.sup.2/V.Math.sec.