Abstract: Photodetector arrays, image sensors, and other apparatus are disclosed. In one aspect, an apparatus may include a surface to receive light, a plurality of photosensitive regions disposed within a substrate, and a material coupled between the surface and the plurality of photosensitive regions. The material may receive the light. At least some of the light may free electrons in the material. The apparatus may also include a plurality of discrete electron repulsive elements. The discrete electron repulsive elements may be coupled between the surface and the material. Each of the discrete electron repulsive elements may correspond to a different photosensitive region. Each of the discrete electron repulsive elements may repel electrons in the material toward a corresponding photosensitive region. Other apparatus are also disclosed, as are methods of use, methods of fabrication, and systems incorporating such apparatus.

Abstract: A photodetector detects the absence or presence of light by detecting a change in the inductance of a coil. The magnetic field generated when a current flows through the coil passes through an electron-hole generation region. Charged particles in the electron-hole generation region come under the influence of the magnetic field, and generate eddy currents whose magnitudes depend on whether light is absent or present. The eddy currents generate a magnetic field that opposes the magnetic field generated by current flowing through the coil.

Abstract: A photocell which operates at multiple wavelengths for efficient power generation from broadband incident radiation. According to a preferred embodiment, the photocell is a multi-layer device that includes a first outer layer, a middle layer and an inner layer disposed on a substrate. All three layers are formed from II-VI semiconductor layers. The device is arranged such that the outer layer has a high band gap, the middle layer has a band gap which is less than half the band gap of the outer layer and the inner layer has a band gap which is less than half that of the substrate. Thus, there is a step change in band gap between various layers.

Abstract: An optical-powered device includes a flexible substrate, a photonic bandgap layer coupled thereto, a waveguide contained within the photonic bandgap layer, and a dendrimer region contained within the waveguide. The dendrimer region may comprise more than one dendrimers. The dendrimer region emission band is within the photonic bandgap of the photonic bandgap layer. Multiple photonic bandgap layers may be included, with one or more waveguides therein. Each waveguide may have a dendrimer region therein. Electronic circuitry may be contained within a portion of the photonic bandgap layer. A light-modulating layer may be directly coupled to the photonic bandgap layer. A portion of the photonic bandgap layer may have a sensing material embedded therein. A cover layer having one or more windows may be coupled to the photonic bandgap layer. Another layer, such as a buffer layer, may be disposed between the substrate layer and the photonic bandgap layer.

Abstract: The invention specifies a radiation detector for detecting radiation (8) according to a predefined spectral sensitivity distribution (9) that exhibits a maximum at a predefined wavelength ?0, comprising a semiconductor body (1) with an active region (5) serving to generate a detector signal and intended to receive radiation, in which according to one embodiment the active region (5) includes a plurality of functional layers (4a, 4b, 4c, 4d) that have different band gaps and/or thicknesses and are implemented such that they (4a, 4b, 4c, 4d) at least partially absorb radiation in a range of wavelengths greater than ?0. According to a further embodiment, disposed after the active region is a filter layer structure (70) comprising at least one filter layer (7, 7a, 7b, 7c), said filter layer structure determining the short-wave side (101) of the detector sensitivity (10) according to the predefined spectral sensitivity distribution (9) by absorbing wavelengths smaller than ?0.

Abstract: Disclosed is a light emitting device including, a light emitting structure that has a first conductive semiconductor layer, an active layer and a second conductive semiconductor layer, wherein the active layer is provided between the first conductive semiconductor layer and the second conductive semiconductor layer, and includes a plurality of well layers and at least one barrier layer, wherein the barrier layer includes a first nitride layer and a second nitride layer provided on the first nitride layer, and wherein the first nitride layer has a larger energy band gap than the second nitride layer while the energy band gap of the second nitride layer is larger than that of each well layer.

Abstract: The present teachings provide a detection cell for a biological material and methods for detecting biological material including a photosensitive material optically coupled to an interior volume containing the biological material so to avoid optical components or an external light source.

Abstract: The semiconductor device includes: a base; a first mount placed on the bottom of the base; a second mount placed on the top of the base; a first light-emitting element placed on the bottom of the first mount; and a second light-emitting element placed on the top of the second mount for emitting light. The first light-emitting element and the second light-emitting element are placed so that the emission direction of light from the second light-emitting element is at an angle of depression with respect to the emission direction of light from the first light-emitting element and that the emission direction of light from the first light-emitting element and the emission direction of light from the second light-emitting element substantially coincide with each other as viewed from above the base.

Abstract: A method of growing a germanium (Ge) epitaxial thin film having negative photoconductance characteristics and a photodiode using the same are provided. The method of growing the germanium (Ge) epitaxial thin film includes growing a germanium (Ge) thin film on a silicon substrate at a low temperature, raising the temperature to grow the germanium (Ge) thin film, and growing the germanium (Ge) thin film at a high temperature, wherein each stage of growth is performed using reduced pressure chemical vapor deposition (RPCVD). The three-stage growth method enables formation of a germanium (Ge) epitaxial thin film characterized by alleviated stress on a substrate, a lowered penetrating dislocation density, and reduced surface roughness.

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: There is provided an image pickup device, including a photoelectric conversion element converting light into charges, a transfer gate for transferring the converted charges to a floating node, a source follower transistor for outputting a signal based on a voltage of the floating node to a signal line, and a clip circuit clipping the signal line at a first voltage and a second voltage.

Abstract: Modeling a monolithic, multi-bandgap, tandem, solar photovoltaic converter or thermophotovoltaic converter by constraining the bandgap value for the bottom subcell to no less than a particular value produces an optimum combination of subcell bandgaps that provide theoretical energy conversion efficiencies nearly as good as unconstrained maximum theoretical conversion efficiency models, but which are more conducive to actual fabrication to achieve such conversion efficiencies than unconstrained model optimum bandgap combinations. Achieving such constrained or unconstrained optimum bandgap combinations includes growth of a graded layer transition from larger lattice constant on the parent substrate to a smaller lattice constant to accommodate higher bandgap upper subcells and at least one graded layer that transitions back to a larger lattice constant to accommodate lower bandgap lower subcells and to counter-strain the epistructure to mitigate epistructure bowing.

Abstract: Embodiments of the invention generally relate to optoelectronic semiconductor devices such as photovoltaic devices including solar cells. In one aspect, an optoelectronic semiconductor device includes an absorber layer made of gallium arsenide (GaAs) and having only one type of doping. An emitter layer is located closer than the absorber layer to a back side of the device, the emitter layer made of a different material than the absorber layer and having a higher bandgap than the absorber layer. A heterojunction formed between the emitter layer and the absorber layer, and a p-n junction is formed between the emitter layer and the absorber layer and at least partially within the different material at a location offset from the heterojunction. The p-n junction causes a voltage to be generated in the device in response to the device being exposed to light at a front side of the device.

Abstract: A method for fabricating a III-nitride semiconductor film, comprising depositing or growing a III-nitride semiconductor film in a semiconductor light absorbing or light emitting device structure; and growing a textured or structured surface of the III-nitride nitride semiconductor film in situ with the growing or the deposition of the III-nitride semiconductor film, by controlling the growing of the III-nitride semiconductor film to obtain a texture of the textured surface, or one or more structures of the structured surface, that increase output power of light from the light emitting device, or increase absorption of light in the light absorbing device.

Abstract: The present invention provides a non-vacuum method of depositing a photovoltaic absorber layer based on electrophoretic deposition of a mixture of nanoparticles with a controlled atomic ratio between the elements. The nanoparticles are first dispersed in a liquid medium to form a colloidal suspension and then electrophoretically deposited onto a substrate to form a thin film photovoltaic absorber layer. The absorber layer may be subjected to optional post-deposition treatments for photovoltaic absorption.

Abstract: A CMOS image sensor includes a substrate including silicon, a silicon germanium (SiGe) epitaxial layer formed over the substrate, the SiGe epitaxial layer formed through epitaxial growth and doped with a predetermined concentration level of impurities, an undoped silicon epitaxial layer formed over the SiGe epitaxial layer by epitaxial growth, and a photodiode region formed from a top surface of the undoped silicon epitaxial layer to a predetermined depth in the SiGe epitaxial layer.

Abstract: A method for producing a light-emitting device, includes: performing, on a first substrate made of III-V group compound semiconductor, crystal growth of a laminated body including an etching easy layer contiguous to the first substrate and a light-emitting layer made of nitride semiconductor; bonding a second substrate and the laminated body; and detaching the second substrate provided with the light-emitting layer from the first substrate by, one of removing the etching easy layer by using a solution etching method, and removing the first substrate and the etching easy layer by using mechanical polishing method.

Abstract: A dilute nitrogen alloy of InNxSb1-x epilayers strained to an epitaxial substrate useful for Long Wavelength Infrared (LWIR) Focal Plane Arrays, and method of fabricating. Strained materials of composition InNxSb1-x exhibiting increased Auger lifetimes and improved absorption properties.

Abstract: Provided is a semiconductor wafer including: a base wafer containing silicon; an inhibitor that has been formed on the base wafer, has an aperture in which a surface of the base wafer is exposed, and inhibits crystal growth; and a light-absorptive structure that has been formed inside the aperture in contact with a surface of the base wafer exposed inside the aperture, where the light-absorptive structure includes a first semiconductor and a second semiconductor.

Abstract: A superlattice structure comprises a plurality of well layers made of first semiconductor and a plurality of barrier layers made of second semiconductor that has a band gap wider than that of the first semiconductor, wherein both layers are deposited alternately, and wherein a maximum thickness of each of the wall and barrier layers is such that a band gap between a lower limit of a mini band generated in a conduction band and an upper limit of a mini band generated in a valence band is a given width in the energy state of electron of the superlattice structure, and a minimum thickness of each of the wall and the barrier layers is such that a bandwidth of a mini band generated in the conduction band is a given width in the energy state of electron of the superlattice structure.

Abstract: Provided is an optical device including a base wafer containing silicon, a plurality of seed crystals disposed on the base wafer, and a plurality of Group 3-5 compound semiconductors lattice-matching or pseudo lattice-matching the plurality of seed crystals. At least one of the Group 3-5 compound semiconductors has a photoelectric semiconductor formed therein, the photoelectric semiconductor including a light emitting semiconductor that emits light in response to a driving current supplied thereto or a light receiving semiconductor that generates a photocurrent in response to light applied thereto, and at least one of the plurality of Group 3-5 compound semiconductors other than the Group 3-5 compound semiconductor having the photoelectric semiconductor has a heterojunction transistor formed therein.

Abstract: A bispectral detector comprising upper and lower semiconductor layers of a first conductivity type in order to absorb a first and a second electromagnetic spectrum, separated by an intermediate layer that forms a barrier; semiconductor zones of a second conductivity type implanted in upper layer and lower layer and each implanted at least partially in the bottom of an opening that passes through upper layer and intermediate layer; and conductor elements connected to semiconductor zones. At least that part of each opening that passes through upper layer is separated from the latter by a semiconductor cap layer: whereof the concentration of dopants of the second conductivity type is greater than 1017 cm?3; and whereof the thickness is chosen as a function of said concentration so that it exceeds the minority carrier diffusion length in the cap layer.

Abstract: A semiconductor detector has a tunable spectral response. These detectors may be used with processing techniques that permit the creation of “synthetic” sensors that have spectral responses that are beyond the spectral responses attainable by the underlying detectors. For example, the processing techniques may permit continuous and independent tuning of both the center wavelength and the spectral resolution of the synthesized spectral response. Other processing techniques can also generate responses that are matched to specific target signatures.

Abstract: A photodiode in which a pn junction is formed between the doped region (DG) formed in the surface of a crystalline semiconductor substrate and a semiconductor layer (HS) deposited above said doped region. An additional doping (GD) is provided in the edge region of the doped zone, by means of which additional doping the pn junction is shifted deeper into the substrate (SU). With the greater distance of the pn junction from defects at phase boundaries that is achieved in this way, the dark current within the photodiode is reduced.

Abstract: An optoelectronic device, including a semiconductor body having a surface to receive photons and a plurality of doped regions of opposite doping polarities, the doped regions extending substantially from the surface of the semiconductor body and into the semiconductor body, and being arranged in one or more pairs of opposite doping polarities such that each pair of doped regions forms a corresponding space charge region having a corresponding electric field therein, the space charge region extending substantially from the surface of the semiconductor body and into the semiconductor body such that photons entering the semiconductor body through the surface and travelling along paths within the space charge region generate electron-hole pairs in the space charge region that are separated in opposing directions substantially orthogonal to the photon paths by the electric field and collected by the corresponding pair of doped regions, thereby providing an electrical current to be conducted from the device.

Abstract: Electronic and opto-electronic devices having epitaxially-deposited III/V compounds on vicinal group IV substrates and method for making same. The devices include an AlAs nucleating layer on a Ge substrate. The group IV substrate contains a p-n junction whose change of characteristics during epitaxial growth of As-containing layers is minimized by the AlAs nucleating layer. The AlAs nucleating layer provides improved morphology of the devices and a means to control the position of a p-n junction near the surface of the group IV substrate through diffusion of As and/or P and near the bottom of the III/V structure through minimized diffusion of the group IV element.

Abstract: A quad photoreceiver includes a low capacitance quad InGaAs p-i-n photodiode structure formed on an InP (100) substrate. The photodiode includes a substrate providing a buffer layer having a metal contact on its bottom portion serving as a common cathode for receiving a bias voltage, and successive layers deposited on its top portion, the first layer being drift layer, the second being an absorption layer, the third being a cap layer divided into four quarter pie shaped sections spaced apart, with metal contacts being deposited on outermost top portions of each section to provide output terminals, the top portions being active regions for detecting light. Four transimpedance amplifiers have input terminals electrically connected to individual output terminals of each p-i-n photodiode.

Abstract: Methods and structures for monolithically integrating monocrystalline silicon and monocrystalline non-silicon materials and devices are provided. In one structure, a monolithically integrated semiconductor device structure comprises a silicon substrate and a first monocrystalline semiconductor layer disposed over the silicon substrate, wherein the first monocrystalline semiconductor layer has a lattice constant different from a lattice constant of relaxed silicon. The structure also includes an insulating layer disposed over the first monocrystalline semiconductor layer in a first region and a monocrystalline silicon layer disposed over the insulating layer in the first region. The structure includes at least one silicon-based electronic device comprising an element including at least a portion of the monocrystalline silicon layer.

Abstract: An image sensor and a method for manufacturing the same are disclosed. The image sensor can include a semiconductor substrate that includes photodiodes arranged for each unit pixel; an interlayer dielectric layer and metal wirings disposed on the semiconductor substrate; and a photorefractive unit that is formed on the periphery of an optical path incident on the photodiodes. The photorefractive unit has a lower refractive index than the interlayer dielectric layer. The slantly incident light can be incident on the photodiodes, while maintaining the slanted optical path as it is. The light sensitivity of the photodiodes can be improved, thereby improving image quality.

Abstract: A complementary metal oxide semiconductor (CMOS) device and a method for fabricating the same are provided. The CMOS image sensor includes: a first conductive type substrate including a trench; a channel stop layer formed by using a first conductive type epitaxial layer over an inner surface of the trench; a device isolation layer formed on the channel stop layer to fill the trench; a second conductive type photodiode formed in a portion of the substrate in one side of the channel stop layer; and a transfer gate structure formed on the substrate adjacent to the photodiode to transfer photo-electrons generated from the photodiode.

Abstract: Nanoscaled, tunable detector devices for ultrasensitive detection of terahertz (THz) radiation based on the fabrication of one-dimensional (1D) plasma devices having clouds of strongly correlated and spatially confined electronic charge carriers are disclosed. These one-dimensional collective excitations (“plasmons”) are realized using coaxial semiconducting core-shell nanowires or by electrostatically confining a two dimensional charge to one dimension. By exploiting the properties of plasmons confined to reduced dimensions and under a selected device configuration, conventional limitations on carrier drift and transit times that dictate the speed and sensitivity of transistors can be circumvented, and detector sensitivity can be improved. 1D devices with sub-picosecond response times will be important for a range of applications in diverse areas such as remote sensing and imaging, molecular spectroscopy, biotechnology, and in a range of the spectrum that has been difficult to detect.

Abstract: A light receiving device having small dark current and capable of sensing light in the wavelength range of 2.0 ?m to 3.0 ?m with high sensitivity is provided. The light receiving device has an InP substrate, and a light receiving layer formed by alternately stacking a larger layer formed of GaInNAsSbP mixed crystal having nitrogen content of at most 5% in 5 group, larger lattice constant than that of InP and thickness between hc and 11hc, the critical thickness hc being determined as hc=b(1?? cos2?){log(hc/b)+1}/8?f(1+?)cos ? and a smaller layer formed of GaInNAsSbP mixed crystal having nitrogen content of at most 5% in 5 group, smaller lattice constant than that of InP and thickness between hc and 11hc; absolute value of lattice mismatch of the larger layer and the smaller layer to the InP substrate is at least 0.5% and at most 5%; at least one of the layers has absorption edge wavelength of 2.0 ?m to 3.0 ?m; total thickness of respective layers is 2.0 ?m to 4.

Abstract: A method of fabricating multi-spectral photo-sensors including photo-diodes incorporating stacked epitaxial superlattices monolithically integrated with CMOS devices on a common semiconductor substrate.

Abstract: The present invention provides of a three-dimensional bicontinuous heterostructure, a method of producing same, and the application of this structure towards the realization of photodetecting and photovoltaic devices working in the visible and the near-infrared. The three-dimensional bicontinuous heterostructure includes two interpenetrating layers which are spatially continuous, they are include only protrusions or peninsulas, and no islands. The method of producing the three-dimensional bicontinuous heterostructure relies on forming an essentially planar continuous bottom layer of a first material; forming a layer of this first material on top of the bottom layer which is textured to produce protrusions for subsequent interpenetration with a second material, coating this second material onto this structure; and forming a final coating with the second material that ensures that only the second material is contacted by subsequent layer.

Abstract: Electrical contact to the front side of a photovoltaic cell is provided by an array of conductive through-substrate vias, and optionally, an array of conductive blocks located on the front side of the photovoltaic cell. A dielectric liner provides electrical isolation of each conductive through-substrate via from the semiconductor material of the photovoltaic cell. A dielectric layer on the backside of the photovoltaic cell is patterned to cover a contiguous region including all of the conductive through-substrate vias, while exposing a portion of the backside of the photovoltaic cell. A conductive material layer is deposited on the back surface of the photovoltaic cell, and is patterned to form a first conductive wiring structure that electrically connects the conductive through-substrate vias and a second conductive wiring structure that provides electrical connection to the backside of the photovoltaic cell.

Abstract: A stacked-layered thin film solar cell and a manufacturing method thereof are provided. The stacked-layered thin film solar cell includes a front electrode layer, a stacked-layered light-absorbing structure, and a back electrode layer. The stacked-layered light-absorbing structure has a p-i-n-type layered structure and consists essentially of I-III-VI compounds, wherein the group III elements at least include indium (In) and aluminum (Al). The p-type layer of the stacked-layered light-absorbing structure is near the front electrode layer while the n-type layer is near the back electrode layer. The Al/In concentration ratio in the p-type layer is higher than that in the n-type layer.

Abstract: Photodiode devices with GeSn active layers can be integrated directly on p+ Si platforms under CMOS-compatible conditions. It has been found that even minor amounts of Sn incorporation (2%) dramatically expand the range of IR detection up to at least 1750 nm and substantially increases the absorption. The corresponding photoresponse can cover of all telecommunication bands using entirely group IV materials.

Abstract: A method of manufacturing a photodetector structure is provided. The method includes forming a structural layer by making a trench in a bulk silicon substrate and filling the trench with a cladding material, forming a single-crystallized silicon layer on the structural layer, and forming a germanium layer on the single-crystallized silicon layer.

Abstract: A semiconductor structure having: an electrically and thermally conductive layer disposed on one surface of the semiconductor structure; an electrically and thermally conductive heat sink; a electrically and thermally conductive carrier layer; a plurality of electrically and thermally nano-tubes, a first portion of the plurality of nano-tubes having proximal ends disposed on a first surface of the carrier layer and a second portion of the plurality of nano-tubes having proximal ends disposed on an opposite surface of the carrier layer; and a plurality of electrically and thermally conductive heat conductive tips disposed on distal ends of the plurality of nano-tubes, the plurality of heat conductive tips on the first portion of the plurality of nano-tubes being attached to the conductive layer, the plurality of heat conductive tips on the second portion of the plurality of nano-tubes being attached to the heat sink.

Abstract: Implementations of quantum well photovoltaic devices are provided. In one embodiment, a photovoltaic device includes an active layer that includes a first barrier layer, a well layer located on the first barrier layer and made of a nitride semiconductor, and a second barrier layer located on the well layer. A metal layer is located adjacent to the active layer.

Abstract: A semiconductor photo detecting element includes a PIN-type photo detecting element and window semiconductor layer. The PIN-type photo detecting element has a semiconductor substrate, a first semiconductor layer, a second semiconductor layer and a third semiconductor layer. The first semiconductor layer is provided on the semiconductor substrate, is lattice-matched to the semiconductor substrate, includes a first conductivity type dopant, and has first band gap energy. The second semiconductor layer is provided on the first semiconductor layer, has the first band gap energy, and has a concentration of the first conductivity type dopant lower than that of the first semiconductor layer or is substantially undoped. The third semiconductor layer is provided on the second semiconductor layer. The window semiconductor layer has second band gap energy larger than the first band gap energy at a light-incoming side with respect to the second semiconductor layer and has a thickness of 5 nm to 50 nm.

Abstract: An organic light-emitting display apparatus includes a plurality of pixels arranged on a substrate, each pixel includes: a display region including at least one pixel thin film transistor and an organic light-emitting device electrically connected to the pixel thin film transistor; and a sensor region electrically connected to the display region to affect an image display of the display region.

Abstract: Novel structures of the photodetector having broad spectral ranges detection capability are provided. The photodetector offers high quantum efficiency>95% over wide spectral ranges, high frequency response>10 GHz (@3 dB). The photodiode array of N×N (or M×N) elements is also provided. The array also offers wide spectral detection ranges ultraviolet to 2500 nm with high quantum efficiency>95% and high frequency response of >10 GHz, cross-talk of <0.1%. In the array, each photodiode is independently addressable and is made either as top-illuminated or as bottom illuminated type detector. The photodiode and its array provided in this invention, could be used in multiple purpose applications such as telecommunication, imaging, and sensing applications including surveillance, satellite tracking, advanced lidar systems, etc. The advantages of this photodetectors are that they are uncooled and performance will not be degraded under wide range of temperature variation.

Abstract: An organic EL display unit is manufactured in an efficient manner. A light emission device (1000) is manufactured by bonding together a driving circuit substrate (100) formed with driving circuit constituted by thin film transistors 11, and a light emission substrate (300) comprising a successively laminated transparent electrode layer 31, bank layer 32 made from insulating material, positive hole injection layer 33, organic EL layer 34 and cathode layer 36.

Abstract: An image sensor having a plurality of micro-lenses disposed on a semiconductor substrate. A first micro-lens has a different focal length, height, shape, curvature, thickness, etc., than a second micro-lens. The image sensor may be back side illuminated or front side illuminated.

Abstract: A dual band photodetector for detecting infrared and ultraviolet optical signals is disclosed. Aspects include homojunction and heterojunction detectors comprised of one or more of GaN, AlGaN, and InGaN. In one aspect ultraviolet/infrared dual-band detector is disclosed that is configured to simultaneously detect UV and IR.

Abstract: To provide a light emitting device high in reliability with a pixel portion having high definition with a large screen. According to a light emitting device of the present invention, on an insulator (24) provided between pixel electrodes, an auxiliary electrode (21) made of a metal film is formed, whereby a conductive layer (20) made of a transparent conductive film in contact with the auxiliary electrode can be made low in resistance and thin. Also, the auxiliary electrode (21) is used to achieve connection with an electrode on a lower layer, whereby the electrode can be led out with the transparent conductive film formed on an EL layer. Further, a protective film (32) made of a film containing hydrogen and a silicon nitride film which are laminated is formed, whereby high reliability can be achieved.

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: A photo-detector comprising: a photo absorbing layer comprising an n-doped semiconductor exhibiting a valence band energy level; a barrier layer, a first side of the barrier layer adjacent a first side of the photo absorbing layer, the barrier layer exhibiting a valence band energy level substantially equal to the valence band energy level of the doped semiconductor of the photo absorbing layer; and a contact area comprising a doped semiconductor, the contact area being adjacent a second side of the barrier layer opposing the first side, the barrier layer exhibiting a thickness and a conductance band gap sufficient to prevent tunneling of majority carriers from the photo absorbing layer to the contact area and block the flow of thermalized majority carriers from the photo absorbing layer to the contact area. Alternatively, a p-doped semiconductor is utilized, and conductance band energy levels of the barrier and photo absorbing layers are equalized.

Abstract: A photovoltaic device and method of manufacturing is disclosed. In one embodiment, the device includes a silicon layer and first and second organic layers. The silicon layer has a first face and a second face. First and second electrodes electrically are coupled to the first and second organic layers. A first heterojunction is formed at a junction between the one of the faces of the silicon layer and the first organic layer. A second heterojunction is formed at a junction between one of the faces of the silicon layer and the second organic layer. The silicon layer may be formed without a p-n junction. At least one organic layer may be configured as an electron-blocking layer or a hole-blocking layer. At least one organic layer may be comprised of phenanthrenequinone (PQ). A passivating layer may be disposed between at least one of the organic layers and the silicon layer. The passivating layer may be organic. At least one of the organic layers may passivate a surface of the silicon layer.