A photodetector comprising a photoabsorber, comprising a doped semiconductor, a contact layer comprising a doped semiconductor and a barrier layer comprising a charge carrier compensated semiconductor, the barrier layer compensated by doping impurities such that it exhibits a valence band energy level substantially equal to the valence band energy level of the photo absorbing layer and a conduction band energy level exhibiting a significant band gap in relation to the conduction band of the photo absorbing layer, the barrier layer disposed between the photoabsorber and contact layers. The relationship between the photo absorbing layer and contact layer valence and conduction band energies and the barrier layer conduction and valance band energies is selected to facilitate minority carrier current flow while inhibiting majority carrier current flow between the contact and photo absorbing layers.

The invention relates to a photo bode type structure (comprising: a support (100) including at least one semiconductor layer, the semiconductor layer (120) including of a first semiconductor zone (10) of a first type of conductivity and a mesa (130) in contact with the semiconductor layer (120). The mesa (130) includes of a second semiconductor zone (20), known as absorption zone, said second semiconductor zone (20) being of a second type of conductivity. The second semiconductor zone has a concentration of majority carriers such that the second semiconductor zone (30) is depleted in the absence of polarization of the structure (1). The structure (1) further comprises a third semiconductor zone (30) of the second type of conductivity made of a third material transparent in the absorbed wavelength range. The third semiconductor zone (30) is interposed between the first and the second semiconductor zones (10, 20) while being at least partially arranged in the semiconductor layer (120). The invention also relates to component and a method for manufacturing such a structure (1).

A photodetector comprising a contact layer; an absorbing region positioned such that light admitted passes into the absorbing region; a diffractive region comprising at least one diffractive element operating to diffract light into the absorbing region; the configuration of the photodetector being determined by computer simulation to determine an optimal diffractive region and absorbing region configuration for optimal quantum efficiency for at least one predetermined wavelength range, the diffractive region operating to diffract light entering through the contact layer such that phases of diffracted waves from locations within the photodetector including waves reflected by sidewalls and waves reflected by the diffractive elements form a constructive interference pattern inside the absorbing region. A method of designing a photodetector comprises using a computer simulation to determine an optimal configuration for at least one wavelength range occurring when waves reflected by the diffractive element form a constructive interference pattern inside the absorbing region.

A photodetector comprising a photoabsorber, comprising a doped semiconductor, a contact layer comprising a doped semiconductor and a barrier layer comprising a charge carrier compensated semiconductor, the barrier layer compensated by doping impurities such that it exhibits a valence band energy level substantially equal to the valence band energy level of the photo absorbing layer and a conduction band energy level exhibiting a significant band gap in relation to the conduction band of the photo absorbing layer, the barrier layer disposed between the photoabsorber and contact layers. The relationship between the photo absorbing layer and contact layer valence and conduction band energies and the barrier layer conduction and valance band energies is selected to facilitate minority carrier current flow while inhibiting majority carrier current flow between the contact and photo absorbing layers.

According to an embodiment, a device comprises a direct conversion compound semiconductor layer configured to convert high energy radiation photons into an electric current, the direct conversion compound semiconductor layer comprising: a pixel array positioned in the direct conversion compound semiconductor layer, including pixels located at an outermost circumference, wherein the pixels comprise signal pads; a guard ring encircling the pixel array, wherein the pixels at the outermost circumference are closest to the guard ring; guard ring contact pads, wherein the guard ring contact pads are situated in place of some of the pixel signal pads at the outermost circumference and connected to the guard ring; wherein the guard ring contact pads are further situated asymmetrically with respect to a symmetry x-axis and a symmetry y-axis of the direct conversion compound semiconductor layer. Other embodiments relates to a detector comprising an array of tiles according to the device, and an imaging system comprising: an x-ray source and the detector.

A hybrid photovoltaic device (1) comprising a thin film solar cell (2) disposed in a first layer (21) comprising an array of vertically aligned nanowires (25), said nanowires having a junction with a first band gap corresponding to a first spectral range. The nanowires (25) form absorbing regions, and non-absorbing regions are formed between the nanowires. A bulk solar cell (3) s disposed in a second layer (31), positioned below the first layer (21), having a junction with a second band gap, which is smaller than said first band gap and corresponding to a second spectral range. The nanowires are provided in the first layer with a lateral density selected a such that a predetermined portion of an incident photonic wave-front will pass through the non-absorbing regions without absorption in the first spectral range, into the bulk solar cell for absorption in both the first spectral range and the second spectral range.

A photovoltaic device includes a substrate structure and a p-type semiconductor absorber layer. A photovoltaic device may include a CdSeTe layer. A process for manufacturing a photovoltaic device includes forming a CdSeTe layer over a substrate. The process includes forming a p-type cadmium selenide telluride absorber layer.

Disclosed are a mercury cadmium telluride-black phosphorus van der Waals heterojunction infrared polarization detector and a preparation method thereof. The structure of the detector from bottom to top comprises a substrate, a mercury cadmium telluride material, an insulating layer, a two-dimensional semiconductor black phosphorus, and metal electrodes. First, growing the mercury cadmium telluride material on the substrate, removing part of the mercury cadmium telluride by ultraviolet lithography and argon ion etching, filling with aluminum oxide as the insulating layer using an electron beam evaporation method, transferring the two-dimensional semiconductor material black phosphorus at the junction of mercury cadmium telluride and an insulating layer assisted by a polypropylene carbonate film, and preparing the metal source-drain electrodes by electron beam lithography technology combined with the lift-off process to form the mercury cadmium telluride-black phosphorus van der Waals heterojunction infrared polarization detector.

A Terahertz Source and Detector device is provided that includes a nanostructured metasurface configured to transmit fully into a layer of absorbing material below the metasurface to achieve transparent conductivity in the visible spectrum region, wherein the metasurface is composed of crystalline material with very high mobility. The crystalline material can be composed of HgCdTe. The HgCdTe material can have a bandgap of about 700 meV. The intrinsic carrier concentration can be 10.sup.12 cm.sup.−3 at 300K.

Embodiments of a photovoltaic device are provided herein. The photovoltaic device can include a layer stack and an absorber layer disposed on the layer stack. The absorber layer can include a first region and a second region. Each of the first region of the absorber layer and the second region of the absorber layer can include a compound comprising cadmium, selenium, and tellurium. An atomic concentration of selenium can vary across the absorber layer. The first region of the absorber layer can have a thickness between 100 nanometers to 3000 nanometers. The second region of the absorber layer can have a thickness between 100 nanometers to 3000 nanometers. A ratio of an average atomic concentration of selenium in the first region of the absorber layer to an average atomic concentration of selenium in the second region of the absorber layer can be greater than 10.