A semiconductor bipolar phototransistor (PT) comprises a floating base consisting of a base (b) electrically coupled only to (i) an emitter (e) via an emitter junction (ej); and (ii) a collector (c) via a collector junction (cj) conductively, capacitively or inductively. A substantially planar semiconductor interface is formed between the semiconductor and a dielectric. A semiconductor volume of highest bandgap (Eg) whose bandgap is higher than the bandgap of the remaining semiconductor volume of the semiconductor bipolar phototransistor (PT) within about 1 micron linear distance from the substantially planar semiconductor interface with the dielectric. The emitter junction (ej) comprises an emitter junction (ej) portion with a bandgap lower than the bandgap of the highest bandgap volume. The base (b) comprises a base (b) portion with a bandgap lower than the bandgap of the highest bandgap volume. The collector junction (cj) comprises a collector junction (cj) portion with a bandgap lower than the bandgap of the highest bandgap volume. A first low-doped region of the highest bandgap volume resides within the emitter junction (ej). A second low-doped region of the highest bandgap volume resides within the base (b). A third low-doped region of the highest bandgap volume resides within the collector junction (cj). A minimum linear dimension of the highest bandgap volume is at least 10 nanometers. The highest bandgap volume is substantially single crystalline. The first, second, and third low-doped regions of the highest bandgap volume are not doped to higher than 10.sup.16/cm.sup.3.

A semiconductor bipolar phototransistor (PT) comprises a floating base consisting of a base (b) electrically coupled only to (i) an emitter (e) via an emitter junction (ej); and (ii) a collector (c) via a collector junction (cj) conductively, capacitively or inductively. A substantially planar semiconductor interface is formed between the semiconductor and a dielectric. A semiconductor volume of highest bandgap (Eg) whose bandgap is higher than the bandgap of the remaining semiconductor volume of the semiconductor bipolar phototransistor (PT) within about 1 micron linear distance from the substantially planar semiconductor interface with the dielectric. The emitter junction (ej) comprises an emitter junction (ej) portion with a bandgap lower than the bandgap of the highest bandgap volume. The base (b) comprises a base (b) portion with a bandgap lower than the bandgap of the highest bandgap volume. The collector junction (cj) comprises a collector junction (cj) portion with a bandgap lower than the bandgap of the highest bandgap volume. A first low-doped region of the highest bandgap volume resides within the emitter junction (ej). A second low-doped region of the highest bandgap volume resides within the base (b). A third low-doped region of the highest bandgap volume resides within the collector junction (cj). A minimum linear dimension of the highest bandgap volume is at least 10 nanometers. The highest bandgap volume is substantially single crystalline. The first, second, and third low-doped regions of the highest bandgap volume are not doped to higher than 10.sup.16/cm.sup.3.

A stacked (or vertically arranged) photodetector having at least one contact region on a germanium sensing region. Including the at least one contact on the germanium sensing region reduces the amount of surface area of the germanium sensing region that is interfaced with a substrate (e.g., a silicon substrate) in which the germanium sensing region is included. This reduces the amount of lattice mismatch reduces the amount of misfit defects for the germanium sensing region, which reduces the dark current for the photodetector. The reduced amount of dark current may increase the photosensitivity of the photodetector, may increase low-light performance of the photodetector, and/or may decrease noise and other defects in images and/or light captured by the photodetector, among other examples.

A radiation detection device includes at least one heterojunction Schottky barrier diode (HSBD). The at least one HSBD includes at least one boron-doped diamond layer located on top of at least one epitaxial layer, the epitaxial layer located on top of at least one buffer layer, and the buffer layer located on top of a bulk substrate layer. At least one contact layer is located on a side of the bulk substrate layer opposite the epitaxial layer.

A radiation detection device includes at least one heterojunction Schottky barrier diode (HSBD). The at least one HSBD includes at least one boron-doped diamond layer located on top of at least one epitaxial layer, the epitaxial layer located on top of at least one buffer layer, and the buffer layer located on top of a bulk substrate layer. At least one contact layer is located on a side of the bulk substrate layer opposite the epitaxial layer.

Provided are a silicon carbide detector and a fabrication method thereof. The silicon carbide detector includes: a silicon carbide substrate layer; and a silicon carbide base layer located on a side of the silicon carbide substrate layer, where the silicon carbide base layer includes a first silicon carbide layer, a second silicon carbide layer and a third silicon carbide layer that are stacked; the third silicon carbide layer serves as an anode layer and is located in a first region of the second silicon carbide layer, and a second region of the second silicon carbide layer is exposed; N drift rings are provided in the second region of the second silicon carbide layer, and among the N drift rings, a 1st drift ring is a closed ring and remaining drift rings are arranged in a spiral pattern around the 1st drift ring.