Disclosed are a method of forming a photodetector and a photodetector structure. In the method, a polycrystalline or amorphous light-absorbing layer is formed on a dielectric layer such that it is in contact with a monocrystalline semiconductor core of an optical waveguide. The light-absorbing layer is then encapsulated in one or more strain-relief layers and a rapid melting growth (RMG) process is performed to crystallize the light-absorbing layer. The strain-relief layer(s) are tuned for controlled strain relief so that, during the RMG process, the light-absorbing layer remains crack-free. The strain-relief layer(s) are then removed and an encapsulation layer is formed over the light-absorbing layer (e.g., filling in surface pits that developed during the RMG process). Subsequently, dopants are implanted through the encapsulation layer to form diffusion regions for PIN diode(s). Since the encapsulation layer is relatively thin, desired dopant profiles can be achieved within the diffusion regions.

A photoconductive device that generates or detects terahertz radiation includes a semiconductor layer; a structure portion; and an electrode. The semiconductor layer has a thickness no less than a first propagation distance and no greater than a second propagation distance, the first propagation distance being a distance that the surface plasmon wave propagates through the semiconductor layer in a perpendicular direction of an interface between the semiconductor layer and the structure portion until an electric field intensity of the surface plasmon wave becomes 1/e times the electric field intensity of the surface plasmon wave at the interface, the second propagation distance being a distance that a terahertz wave having an optical phonon absorption frequency of the semiconductor layer propagates through the semiconductor layer in the perpendicular direction until an electric field intensity of the terahertz wave becomes 1/e.sup.2 times the electric field intensity of the terahertz wave at the interface.

A ultraviolet detector includes a substrate; a first epitaxial layer that is a heavily doped epitaxial layer and located on the substrate, a second epitaxial layer located on the first epitaxial layer, where the second epitaxial layer is a lightly doped epitaxial layer, or a double-layer or multi-layer structure composed of at least one lightly doped epitaxial layer and at least one heavily doped epitaxial layer; an ohmic contact layer located on the second epitaxial layer or formed in the second epitaxial layer, where the ohmic contact layer is a graphical heavily doped layer; and a first metal electrode layer located on the ohmic contact layer.

A first photodetector according to an embodiment of the present disclosure includes: a substrate having a first surface that serves as a light-receiving surface and a second surface opposed to the first surface, and including an uneven structure provided on the first surface and a light-receiving section that performs photoelectric conversion to generate electric charge corresponding to an amount of light reception for each pixel; a passivation film stacked on the first surface of the substrate; and a reflectance adjustment layer including a plurality of protrusions configuring the uneven structure and the passivation film embedded in a plurality of recesses configuring the uneven structure, and having a refractive index between the substrate and the passivation film.

A diode for detecting the presence of radiation includes a P region, an N region, an intrinsic region located between the P region and the N region, and a layer of nanoclusters located adjacent to the intrinsic region.

BSI image sensors and methods. In an embodiment, a substrate is provided having a sensor array and a periphery region and having a front side and a back side surface; a bottom anti-reflective coating (BARC) is formed over the back side to a first thickness, over the sensor array region and the periphery region; forming a first dielectric layer over the BARC; a metal shield is formed; selectively removing the metal shield from over the sensor array region; selectively removing the first dielectric layer from over the sensor array region, wherein a portion of the first thickness of the BARC is also removed and a remainder of the first thickness of the BARC remains during the process of selectively removing the first dielectric layer; forming a second dielectric layer over the remainder of the BARC and over the metal shield; and forming a passivation layer over the second dielectric layer.

A semiconductor layered structure according to the present invention includes a substrate formed of a III-V compound semiconductor; and semiconductor layers disposed on the substrate and formed of III-V compound semiconductors. The substrate has a majority-carrier-generating impurity concentration of 110.sup.17 cm.sup.3 or more and 210.sup.20 cm.sup.3 or less, and the impurity has an activation ratio of 30% or more.

Structures and techniques introduced here enable the design and fabrication of photodetectors (PDs) and/or other electronic circuits using typical semiconductor device manufacturing technologies meanwhile reducing the adverse impacts on PDs performance. Examples of the various structures and techniques introduced here include, but not limited to, a pre-PD homogeneous wafer bonding technique, a pre-PD heterogeneous wafer bonding technique, a post-PD wafer bonding technique, their combinations, and a number of mirror equipped PD structures. With the introduced structures and techniques, it is possible to implement PDs using typical direct growth material epitaxy technology while reducing the adverse impact of the defect layer at the material interface caused by lattice mismatch.

A photo detecting device comprising: a substrate; a plurality of photoelectric conversion elements provided to the substrate and configured to output a detection signal corresponding to light with which the photoelectric conversion elements are irradiated; at least one or more light emitting elements provided to the substrate; and a control circuit configured to set a wavelength of light output from the light emitting element by controlling an electric current flowing through the light emitting element.

Silicon-based or other electronic circuitry is dissolved or otherwise disabled by reactive materials within a semiconductor chip should the chip or a device containing the chip be subjected to tampering. Triggering circuits containing normally-OFF heterojunction field-effect photo-transistors are configured to cause reactions of the reactive materials within the chips upon exposure to light. The normally-OFF heterojunction field-effect photo-transistors can be fabricated during back-end-of-line processing through the use of polysilicon channel material, amorphous hydrogenated silicon gate contacts, hydrogenated crystalline silicon source/drain contacts, or other materials that allow processing at low temperatures.