A semiconductor device is provided, which includes a first semiconductor structure, a second semiconductor structure, and an active region. The active region is located between the first semiconductor structure and the second semiconductor structure. The active region includes a light-emitting region having N pair(s) of semiconductor stack(s). Each of the semiconductor stack includes a well layer and a barrier layer, in which N is a positive integer greater than or equal to 1. The well layer includes a first group III-V semiconductor material including indium with a first percentage of indium content. The barrier layer includes a second group III-V semiconductor material including indium with a second percentage of indium content. The first group III-V semiconductor material and the second group III-V semiconductor material further includes phosphorus. The second percentage of indium content is less than the first percentage of indium content.

A photodiode, such as a linear mode avalanche photodiode can be made free of excess noise via having a superlattice multiplication region that allows only one electrical current carrier type, such as an electron or a hole, to accumulate enough kinetic energy to impact ionize when biased, where the layers are lattice matched. A photodiode can be constructed with i) a lattice matched pair of a first semiconductor alloy and a second semiconductor alloy in a superlattice multiplication region, ii) an absorber region, and iii) a semiconductor substrate. A detector with multiple photodiodes can be made with these construction layers in order to have a cutoff wavelength varied anywhere from 1.7 to 4.9 m as well as a noise resulting from a dark current at a level such that an electromagnetic radiation signal with the desired minimum wavelength cutoff can be accurately sensed by the photodiode.

The invention relates to a detector element which has the following features: an epitaxial semiconductor layer sequence including at least two active layers which are designed to absorb electromagnetic radiation with a wavelength L1, wherein the epitaxial semiconductor layer sequence has a first main surface and a second main surface lying opposite the first main surface, each surface being designed to couple in and couple out electromagnetic radiation, and at least three electric connection contacts which are designed to electrically contact the active layers, an electric connection contact being arranged between two active layers. The invention additionally relates to a lidar module and to a method for operating a lidar module.

A superlattice structure for a thin film solar cell includes superimposed layers of nanocrystals and is configured to generate a flow of electrons across the layers when it is irradiated by a solar radiation. Each of the layers includes an array of nanocrystals which have substantially the same size and shape and the nanocrystals of each of the layers have different size and/or different shape with respect to the nanocrystals of the other layers. The layers are sorted in such an order that the superlattice structure is anisotropic. A thin film solar cell having the superlattice structure and a method for making the superlattice structure is related.

A camera having an integrated dewar cooler assembly (IDCA) with an optical window, and a reduced dark current photodetector disposed within the IDCA to receive light passing through the optical window. The photodetector comprising a semiconductor photo absorbing layer, a semiconductor barrier layer having a thickness and a first side adjacent a side of the photo absorbing layer, the barrier layer exhibiting 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 an energy gap in relation to the conduction band of the photo absorbing layer, and a contact area comprising a doped semiconductor, the contact area is adjacent a second side of the barrier layer opposing the first side. The energy gap and/or the thickness of the of the barrier layer is sufficient to minimize charge carriers tunneling and thermalization.

Systems, devices, and methods for optical sensing applications. An example multi-wavelength light emitter structure including a substrate; and a vertical structure over the substrate and extending vertically away from the substrate along an axis, the vertical structure comprising a first active region including one or more cascade stages of superlattices for light emission at a first wavelength; a second active region including one or more cascade stages of superlattices for light emission at a second wavelength different from the first wavelength, wherein the second active region is closer to the substrate than the first active region and spaced apart from the first active region; and an electrically conductive material along sidewalls of at least one of the first active region or the second active region.

An infrared detector and a method for forming it are provided. The detector includes absorber, barrier, and contact regions. The absorber region includes a first semiconductor material, with a first lattice constant, that produces charge carriers in response to infrared light. The barrier region is disposed on the absorber region and comprises a superlatice that includes (i) first barrier region layers comprising the first semiconductor material, and (ii) second barrier region layers comprising a second semiconductor material, different from, but lattice matched to, the first semiconductor material. The first and second barrier region layers are alternatingly arranged. The contact region is disposed on the barrier region and comprises a superlattice that includes (i) first contact region layers comprising the first semiconductor material, and (ii) second contact region layers comprising the second semiconductor material layer. The first and second contact region layers are alternatingly arranged.

In one aspect, an avalanche photodiode, includes an absorber, a first superlattice structure directly connected to the absorber and configured to multiply holes and a second superlattice structure directly connected to the first superlattice structure and configured to multiply electrons. The first and second superlattice structures include III-V semiconductor material. The avalanche photodiode is a dual mode device configured to operate in either a linear mode or a Geiger mode. In another aspect, a method includes fabricating the avalanche diode.

A contact to a semiconductor heterostructure is described. In one embodiment, there is an n-type semiconductor contact layer. A light generating structure formed over the n-type semiconductor contact layer has a set of quantum wells and barriers configured to emit or absorb target radiation. An ultraviolet transparent semiconductor layer having a non-uniform thickness is formed over the light generating structure. A p-type contact semiconductor layer having a non-uniform thickness is formed over the ultraviolet transparent semiconductor layer.

In accordance with an embodiment, a diode comprises a substrate, a dielectric material including an opening that exposes a portion of the substrate, the opening having an aspect ratio of at least 1, a bottom diode material including a lower region disposed at least partly in the opening and an upper region extending above the opening, the bottom diode material comprising a semiconductor material that is lattice mismatched to the substrate, a top diode material proximate the upper region of the bottom diode material, and an active diode region between the top and bottom diode materials, the active diode region including a surface extending away from the top surface of the substrate.