An organic light emitting diode device can be formed by imprinting a material layer to form an array of non-planar features selected from protrusions and via cavities. The array of non-planar features can be imprinted by moving the material layer under a rolling press or under a rolling die that transfers a pattern thereupon. A layer stack including a transparent electrode layer, an organic light emitting material layer, and a backside electrode layer is formed over the array of non-planar features such that convex sidewalls of the organic light emitting material layer contact concave sidewalls of the backside electrode layer. The layer stack can be encapsulated with a passivation substrate. Additionally or alternatively, an array of convex lenses can be imprinted on a transparent material layer to decrease total internal reflection of an organic light emitting diode device.

A method (200) for fabricating thin-film optoelectronic devices (100), the method comprising: providing a substrate (110), forming a back-contact layer (120); forming at least one absorber layer (130) made of an ABC chalcogenide material, adding at least one alkali metal (235), and forming at least one cavity (236, 610, 612, 613) at the surface of the absorber layer wherein forming of said at least one cavity is by dissolving away from said surface of the absorber layer at least one crystal aggregate comprising at least one alkali crystal comprising at least one alkali metal. The method (200) is advantageous for more environmentally-friendly production of photovoltaic devices (100) on flexible substrates with high photovoltaic conversion efficiency and faster production rate.

After forming an absorber layer containing cracks over a back contact layer, a passivation layer is formed over a top surface of the absorber layer and interior surfaces of the cracks. The passivation layer is deposited in a manner such that that the cracks in the absorber layer are fully passivated by the passivation layer. An emitter layer is then formed over the passivation layer to pinch off upper portions of the cracks, leaving voids in lower portions of the cracks.

Various particular embodiments include a method for forming a photodetector, including: forming a structure including a barrier layer disposed between a layer of doped silicon (Si) and a layer of germanium (Ge), the barrier layer including a crystallization window; and annealing the structure to convert, via the crystallization window, the Ge to a first composition of silicon germanium (SiGe) and the doped Si to a second composition of SiGe.

A solar cell includes a substrate having a front surface and a back surface; an emitter formed on the front surface of the substrate; a plurality of first electrodes positioned on the emitter and extended in first direction; a plurality of first bus lines positioned on the emitter and extended in second direction crossing to the first direction; a plurality of back surface field regions formed on the back surface of the substrate and extended in the first direction; a plurality of second electrodes positioned on the plurality of back surface field regions and extended in the first direction; and, a plurality of second bus lines extended in the second direction.

A particle detector includes a support member. A front electrode layer is disposed over the support member. A semiconductor heterojunction is disposed over the front electrode layer. The semiconductor heterojunction has at least a polycrystalline n-type layer and at least a polycrystalline p-type layer. A back electrode layer is disposed over the semiconductor heterojunction. The back electrode includes at least one removed portion that separates a first portion of the back electrode layer from a second portion of the back electrode layer. The particle detector also includes a first body of electrically insulating material which separates a first portion of the semiconductor heterojunction from a second portion of the semiconductor heterojunction. The first body of electrically insulating material also separates a first portion of the front electrode layer from a second portion of the front electrode layer.

A photodiode has an absorption layer and a cap layer operatively connected to the absorption layer. A pixel is formed in the cap layer and extends into the absorption layer to receive charge generated from photons therefrom. The pixel defines an annular diffused area to reduce dark current and capacitance. A photodetector includes the photodiode. The photodiode includes includes an array of pixels formed in the cap layer. At least one of the pixels extends into the absorption layer to receive charge generated from photons therefrom. At least one of the pixels defines an annular diffused area to reduce dark current and capacitance.

In an avalanche photodiode provided with a substrate including a first electrode and a first semiconductor layer, formed of a first conductivity type, which is connected to the first electrode, the configuration is in such a way that, at least an avalanche multiplication layer, a light absorption layer, and a second semiconductor layer having a bandgap that is larger than that of the light absorption layer are layered on the substrate; a second conductivity type conductive region is formed in the second semiconductor layer; and the second conductivity type conductive region is arranged so as to be connected to a second electrode. With the foregoing configuration, an avalanche photodiode having a small dark current and a high long-term reliability can be provided with a simple process. Additionally, the configuration is in such a way that, by removing at least the light absorption layer among the layers which are layered on the peripheral portion, of the substrate, on which the second conductivity type conductive region and the second semiconductor layer around the second conductivity type conductive region are surrounded by that layers, a side face of the light absorption layer is formed. With the configuration, the dark current can be further reduced.

A unit pixel formed on a substrate and configured to convert incident light to an electrical signal is provided. The unit pixel includes: a source having a source voltage supplied thereto and having a silicide layer for metal contact formed thereabove; a drain spaced apart from the source and having a silicide layer for metal contact formed thereabove; a channel formed between the source and the drain and having a current flowed therethrough; an insulating layer formed above the channel; and a floating gate having a nonsal structure in which no silicide layer is formed thereabove in order to facilitate an absorption of light, formed above the insulating layer so as to be placed between the source and the drain, and configured to control an amount of current flowing through the channel by an electric field generated by electron-hole pairs generated by the incident light. A body of the unit pixel is floated, and the electric field is configured to act on the channel by electrons aggregated toward the source and holes aggregated toward the drain by the source voltage supplied to the source.

A method of manufacturing a photodiode including a useful layer made of a semi-conductor alloy. The useful layer has a band gap value which decreases from its upper face to its lower face. A step of producing a first doped region forming a PN junction with a second doped region of the useful layer, said production of a first doped region including a first doping step, so as to produce a base portion; and a second doping step, so as to produce at least one protuberance protruding from the base portion and in the direction of the lower face.