Abstract: A light-receiving element includes a III-V group compound semiconductor substrate, a light-receiving layer having a type II multi-quantum well structure disposed on the substrate, and a type I wavelength region reduction means for reducing light in a wavelength region of type I absorption in the type II multi-quantum well structure disposed on a light incident surface or between the light incident surface and the light-receiving layer.

Abstract: The disclosure relates to multiple quantum well (MQW) structures for intrinsic regions of monolithic photovoltaic junctions within solar cells which are substantially lattice matched to GaAs or Ge. The disclosed MQW structures incorporate quantum wells formed of quaternary InGaAsP, between barriers of InGaP.

Abstract: An InxGa1-xAs interlayer is provided between a III-V base and an intrinsic amorphous semiconductor layer of a heterojunction III-V solar cell structure. Improved surface passivation and open circuit voltage may be obtained through the incorporation of the interlayer within the structure.

Abstract: The present invention relates to optoelectronic device layer structures, light emitting devices, and detectors based upon heterostructures formed between hexagonal boron nitride (hNB) and III-nitrides, and more particularly, to heterojunction devices capable of emitting and detecting photons in the ultraviolet (UV) and extremely ultraviolet (RUV) spectral range. The present invention also relates to neutron detectors based on epitaxially grown hBN thin films (or epitaxial layers) and hBN stacked thin films (or epitaxial layers) to satisfy the thickness required for capturing all incoming neutrons.

Abstract: A high operating temperature split-off band infrared (SPIP) detector having a double and/or graded barrier on either side of the emitter is provided. The photodetector may include a first and second barrier and an emitter disposed between the first and second barriers so as to form a heterojunction at each interface between the emitter and the first and second barriers, respectively. The emitter may be of a first semiconductor material having a split-off response to optical signals, while one of the first or the second barriers may include a double barrier having a light-hole energy band level that is aligned with the split-off band energy level of the emitter. In addition, the remaining barrier may be graded.

Abstract: The present disclosure provides a high-speed laser power converter (LPC). The LPC is able to be cascaded. The LPC has a high-speed photodiode (PD) performance even operated under a forward bias operational voltage. Thus, the present disclosure can generate power (instead of consume power) during high-speed data transmission in an optical interconnect (OI) system using 850 nano-meters (nm) wavelength vertical cavity surface-emitting laser (VCSEL).

Abstract: An InxGa1-xAs interlayer is provided between a III-V base and an intrinsic amorphous semiconductor layer of a heterojunction III-V solar cell structure. Improved surface passivation and open circuit voltage may be obtained through the incorporation of the interlayer within the structure.

Abstract: Inverted metamorphic multijunction solar cells having a heterojunction middle subcell and a graded interlayer, and methods of making same, are disclosed herein. The present disclosure provides a method of manufacturing a solar cell using an MOCVD process, wherein the graded interlayer is composed of (InxGa1-x)y Al1-yAs, and is formed in the MOCVD reactor so that it is compositionally graded to lattice match the middle second subcell on one side and the lower third subcell on the other side, with the values for x and y computed and the composition of the graded interlayer determined so that as the layer is grown in the MOCVD reactor, the band gap of the graded interlayer remains constant at 1.5 eV throughout the thickness of the graded interlayer.

Abstract: An object of the present invention is to provide a group III-V compound semiconductor photo detector comprising an absorption layer having a group III-V compound semiconductor layer containing Sb as a group V constituent element, and an n-type InP window layer, resulting in reduced dark current. The InP layer 23 grown on the absorption layer 23 contains antimony as impurity, due to the memory effect with antimony which is supplied during the growth of a GaAsSb layer of the absorption layer 21. In the group III-V compound semiconductor photo detector 11, the InP layer 23 contains antimony as impurity and is doped with silicon as n-type dopant. Although antimony impurities in the InP layer 23 generate holes, the silicon contained in the InP layer 23 compensates for the generated carriers. As a result, the second portion 23d of the InP layer 23 has sufficient n-type conductivity.

Abstract: Provided are a light-receiving element which has sensitivity in the near-infrared region and in which a good crystal quality is easily obtained, a one-dimensional or two-dimensional array of the light-receiving elements is easily formed with a high accuracy, and a dark current can be reduced; a light-receiving element array; and methods for producing the same. A light-receiving element includes a group III-V compound semiconductor stacked structure including an absorption layer 3 having a pn-junction 15 therein, wherein the absorption layer has a multiquantum well structure composed of group III-V compound semiconductors, the pn-junction 15 is formed by selectively diffusing an impurity element into the absorption layer, and the concentration of the impurity element in the absorption layer is 5×1016 cm?3 or less.

Abstract: A method for manufacturing a semiconductor optical device includes forming a BDR (Band Discontinuity Reduction) layer of a first conductivity type doped with an impurity, depositing a contact layer of the first conductivity type in contact with the BDR layer after forming the the BDR layer, the contact layer being doped with the same impurity as the BDR layer and used to form an electrode, and heat treating after forming the contact layer.

Abstract: Provided are an optical receiver and a method of forming the same. The optical receiver includes a lens, a photo detector, and a hetero-junction bipolar transistor. The lens is attached to a backside of a substrate. The photo detector is disposed on a top surface of the substrate. The hetero-junction bipolar transistor is disposed on the top surface of the substrate. The lens condenses an incident optical signal to transmit the condensed optical signal to the photo detector.

Abstract: A waveguide photodetector detecting light incident on a light detecting end face includes: a substrate; and a layer stack structure on the substrate and including a semiconductor layer of a first conductivity type, an undoped semiconductor layer, and a semiconductor layer of a second conductivity type. The undoped semiconductor layer includes two or more undoped light absorbing layers and undoped non-light-absorbing layers. One non-light-absorbing layer is disposed between adjacent undoped light absorbing layers. The non-light-absorbing layers have a bandgap wavelength shorter than the wavelength of the incident light that is detected.

Abstract: An infrared photodetector including a layer structure of an intermediate layer, and a quantum dot layer having a narrower band gap than the intermediate layer and including a plurality of quantum dots alternately stacked, and detecting photocurrent generated when infrared radiation is applied to the layer structure to thereby detect the infrared radiation, the infrared photodetector further including a first barrier layer provided on one side of the quantum dot layer and having a larger band gap than the intermediate layer; and a second barrier layer provided on the other side of the quantum dot layer and having a larger band gap than the intermediate layer.

Abstract: A photo-detector, in which metal wiring for connecting electrodes is arranged on a planarized surface and thus the metal wiring arrangement is simplified, and a method of manufacturing the same are provided. The photo-detector includes a multi-layer compound semiconductor layer formed on a compound semiconductor substrate. A number of p-n junction diodes are arranged in a regular order in a selected region of the compound semiconductor layer, and an isolation region for individually isolating the p-n junction diodes is formed by implanting impurity ions in the multi-layer compound semiconductor layer. The isolation region and the surface of the compound semiconductor layer are positioned on the same level. The isolation region may be a Fe-impurity region.

Abstract: A white light-emitting diode is fabricated by metal organic chemical vapor deposition (MOCVD), which can produce a broad band emission covering all the visible range in the spectrum by capping the Indium nitride (InN) and Indium-rich Indium Gallium Nitride (InGaN) quantum dots (QDs) in single or multiple InxGa1-xN/InyGa1-yN quantum wells (QWs) by introducing bursts of at least one of Timethylindium (TMIn), Triethylindium (TEIn) and Ethyldimethylindium (EDMIn), which serve as nuclei for the growth of QDs in QWs. The diode can thus radiate white light ranging from 400 nm to 750 nm by adjusting the In burst parameters.

Abstract: A structure for a gallium-nitride (GaN) based ultraviolet photo detector is provided. The structure contains an n-type contact layer, a light absorption layer, a light penetration layer, and a p-type contact layer, sequentially stacked on a substrate from bottom to top in this order. The layers are all made of aluminum-gallium-indium-nitride (AlGaInN) compound semiconductors. By varying the composition of aluminum, gallium, and indium, the layers, on one hand, can achieve the desired band gaps so that the photo detector is highly responsive to ultraviolet lights having specific wavelengths. On the other hand, the layers have compatible lattice constants so that problems associated with excessive stress are avoided and high-quality epitaxial structure is obtained. The structure further contains a positive electrode, a light penetration contact layer, and an anti-reflective coating layer on top of the p-type contact layer, and a negative electrode on the n-type contact layer.

Abstract: A photodetector and method of detecting far infrared optical signals. In one embodiment of the present invention, the photodetctor has a plurality of N barriers, N being an integer greater than 1, each barrier being a layer of a material made from a first and a second group III elements and a first group V element and characterized by a bandgap. The photodetector further has a plurality of N?1 emitters, each emitter being a layer of material made from a third group III element and a second group V element and characterized by a bandgap different from that of the barriers and having at least one free carrier responsive to optical signals, wherein each emitter is located between two barriers so as to form a heterojunction at each interface between an emitter and a barrier.

Abstract: An optical device includes an antimonide-containing substrate, and an antimonide-containing n-doped layer provided on the substrate. The optical device further includes an antimonide-containing i-doped layer provided on the n-doped layer, an antimonide-containing p-doped layer provided on the i-doped layer, and an antimonide-containing p+-doped layer provided on the p-doped layer.