A photosensitive transistor is disclosed herein that includes: a semiconductor substrate of the first conductivity type as a collector layer; above it a less doped layer of the first conductivity type having regions of different thickness; a semiconductor base layer of the second conductivity type above at least parts of the regions of the less doped layer; and an emitter layer of the first conductivity type above at least parts of the base layer, but not above at least one part of the part of the base layer disposed above the thinner region of the less doped layer.

Semiconductor devices, such as photonics devices, employ substantially curved-shaped Silicon-Germanium (SiGe) structures and are fabricated using zero-change CMOS fabrication process technologies. In one example, a closed-loop resonator waveguide-coupled photodetector includes a silicon resonator structure formed in a silicon substrate, interdigitated n-doped well-implant regions and p-doped well-implant regions forming multiple silicon p-n junctions around the silicon resonator structure, and a closed-loop SiGe photocarrier generation region formed in a pocket within the interdigitated n-doped and p-doped well implant regions. The closed-loop SiGe region is located so as to substantially overlap with an optical mode of radiation when present in the silicon resonator structure, and traverses the multiple silicon p-n junctions around the silicon resonator structure. Electric fields arising from the respective p-n silicon junctions significantly facilitate a flow of the generated photocarriers between electric contact regions of the photodetector.

An optoelectric device includes a quantum dot core and an intermediate provided on at least a part of a surface of the quantum dot core, thereby converting light energy incident upon the optoelectric device to electrical energy.

An optoelectronic semiconductor structure includes a first n-type semiconductor layer, a first quantum well layer, a first p-type semiconductor layer, and a second n-type semiconductor layer. The first quantum well layer is disposed on the first n-type semiconductor layer. The first p-type semiconductor layer is disposed on the first quantum well layer. The second n-type semiconductor layer is disposed on the first p-type semiconductor layer. The second n-type semiconductor layer includes both an n-type dopant and a p-type dopant. The concentration of the n-type dopant in the second n-type semiconductor layer is greater than the concentration of the p-type dopant in the second n-type semiconductor layer. The first n-type semiconductor layer, the first quantum well layer, the first p-type semiconductor layer, and the second n-type semiconductor layer form a bipolar phototransistor structure. A manufacturing method of the optoelectronic semiconductor structure is also provided.

Methods and devices for an avalanche photo-transistor. In one aspect, an avalanche photo-transistor includes a detection region configured to absorb light incident on a first surface of the detection region and generate one or more charge carriers in response, a first terminal in electrical contact with the detection region and configured to bias the detection region, an interim doping region, a second terminal in electrical contact with the interim doping region and configured to bias the interim doping region, a multiplication region configured to receive the one or more charge carriers flowing from the interim doping region and generate one or more additional charge carriers in response, a third terminal in electrical contact with the multiplication region and configured to bias the multiplication region, wherein the interim doping region is located in between the detection region and the multiplication region.

In accordance with various embodiments of the disclosed subject matter, a phototransistor comprises an NPN or PNP phototransistor having a base including a Si-region, a Ge-region, and a Ge-Si interface region wherein photons are absorbed in the Ge region and conduction-band electrons are attracted to the interface region such that the electrons' mobility is enhanced thereby.

A photo-current amplification apparatus is provided. The photo-current amplification apparatus includes a photo-detecting device including: a substrate; an absorption region comprising germanium, the absorption region supported by the substrate and configured to receive an optical signal and to generate a first electrical signal based on the optical signal; an emitter contact region of a conductivity type; and a collector contact region of the conductivity type, wherein at least one of the emitter contact region or the collector contact region is formed outside the absorption region, and wherein a second electrical signal collected by the collector contact region is greater than the first electrical signal generated by the absorption region.

A lateral interband Type II engineered (LITE) detector is provided. LITE detectors use engineered heterostructures to spatially separate electrons and holes into separate layers. The device may have two configurations, a positive intrinsic (PIN) configuration and a BJT (Bipolar junction transistor) configuration. The PIN configuration may have a wide bandgap (WBG) layer that transports the holes above a narrow bandgap (NBG) absorber layer that absorbs the target radiation and transports the electrons. The BJT configuration may have a WBG layer operating as a BJT above an NBG layer. In both configurations, the LITE design uses a Type II staggered offset between the NBG layers and the WBG layers that provides a built-in field for the holes to drift from an absorber region to a transporter region.

An opto-electronic High Electron Mobility Transistor (HEMT) may include a current channel including a two-dimensional electron gas (2DEG). The opto-electronic HEMT may further include a photoelectric bipolar transistor embedded within at least one of a source and a drain of the HEMT, the photoelectric bipolar transistor being in series with the current channel of the HEMT.

An opto-electronic High Electron Mobility Transistor (HEMT) may include a current channel including a two-dimensional electron gas (2DEG). The opto-electronic HEMT may further include a photoelectric bipolar transistor embedded within at least one of a source and a drain of the HEMT, the photoelectric bipolar transistor being in series with the current channel of the HEMT.