A quantum dot structure, a radiation conversion element and a light emitting device are disclosed. In an embodiment a quantum dot structure includes an active region configured to emit radiation, a barrier region surrounding the active region and a trap region spaced apart from the active region, wherein a band edge of the trap region forms a trap configuration with respect to the barrier region for at least one type of charge carrier.

Disclosed herein are photonic materials. The photonic materials comprise a first layer, a second layer, and a third layer, wherein the second layer is disposed between and in contact with the first layer and the third layer, such that the second layer is sandwiched between the first layer and the third layer. In some examples, the first layer comprises In.sub.yGa.sub.1-.sub.yN, wherein y is from 0 to 0.8. In some examples, the second layer comprises (Zn.sub.aSn.sub.bGe.sub.c).sub.xGa.sub.dN.sub.2, wherein: x is from greater than 0 to 1; a, b, c, and d are each independently from 0 to 1; with the proviso that at least one of a, b, or c is greater than 0. In some examples, the third layer comprises In.sub.zGa.sub.1-.sub.zN, wherein z is from 0 to 0.8.

An image sensor with embedded wells for accommodating light emitters includes a semiconductor substrate including an array of doped sensing regions respectively corresponding to an array of photosensitive pixels of the image sensor. The semiconductor substrate forms an array of wells. Each well is aligned with a respective doped sensing region to facilitate detection, by the photosensitive pixel that includes said respective doped sensing region, of light emitted to the photosensitive pixel by a light emitter disposed in the well. The image sensor further includes, between adjacent doped sensing regions, a light-blocking barrier to reduce propagation of light to the doped sensing-region of each photosensitive pixel from wells not aligned therewith.

A non-diffusion type photodiode is described and has: a substrate, a buffer layer, a light absorption layer, an intermediate layer, and a multiplication/window layer. The buffer layer is disposed on the substrate. The light absorption layer is disposed on the buffer layer. The intermediate layer is disposed on the light absorption layer and has a first boundary, wherein the intermediate layer is an I-type semiconductor layer or a graded refractive index layer. The multiplication/window layer is disposed on the intermediate layer and has a second boundary, wherein in a top view, the first boundary surrounds the second boundary, and a distance between the first boundary and the second boundary is greater than or equal to 1 micrometer. The non-diffusion type photodiode can reduce generation of dark current.

A non-diffusion type photodiode is described and has: a substrate, a buffer layer, a light absorption layer, an intermediate layer, and a multiplication/window layer. The buffer layer is disposed on the substrate. The light absorption layer is disposed on the buffer layer. The intermediate layer is disposed on the light absorption layer and has a first boundary, wherein the intermediate layer is an I-type semiconductor layer or a graded refractive index layer. The multiplication/window layer is disposed on the intermediate layer and has a second boundary, wherein in a top view, the first boundary surrounds the second boundary, and a distance between the first boundary and the second boundary is greater than or equal to 1 micrometer. The non-diffusion type photodiode can reduce generation of dark current.

A solar cell device includes a supporting substrate, and an epitaxial active structure that is disposed on the supporting substrate. The epitaxial active structure has a bottom surface adjacent to the supporting substrate and a top surface opposite to the bottom surface, and is formed with an isolation section that extends from the top surface to the bottom surface. A method for producing the solar cell device is also disclosed.

A single-photon detection pixel includes a substrate, a first well provided in the substrate, a pair of heavily doped regions provided on the first well, and a contact provided between the pair of heavily doped regions, wherein the substrate and the pair of heavily doped regions have a first conductivity type, and the first well and the contact have a second conductivity type that is different from the first conductivity type.

Techniques for enhancing the absorption of photons in semiconductors with the use of microstructures are described. The microstructures, such as pillars and/or holes, effectively increase the effective absorption length resulting in a greater absorption of the photons. Using microstructures for absorption enhancement for silicon photodiodes and silicon avalanche photodiodes can result in bandwidths in excess of 10 Gb/s at photons with wavelengths of 850 nm, and with quantum efficiencies of approximately 90% or more.

An infrared detector includes: a first light receiving layer having a first cutoff wavelength; a second light receiving layer having a second cutoff wavelength longer than the first cutoff wavelength; an intermediate filter layer having a third cutoff wavelength that is the same as or longer than the first cutoff wavelength and the same as or shorter than the second cutoff wavelength, the intermediate filter layer being disposed between the first light receiving layer and the second light receiving layer; a first barrier layer disposed between the first light receiving layer and the intermediate filter layer; and a second barrier layer disposed between the second light receiving layer and the intermediate filter layer.

Devices for generating electrical energy along with methods of fabrication and methods of use are disclosed. An example device can comprise one or more layers of a transition metal dichalcogenide material. An example device can comprise a mechano-electric generator. Another example device can comprise a thermoelectric generator.