An optical sensing apparatus including: a substrate including a first material; an absorption region including a second material different from the first material; an amplification region formed in the substrate and configured to collect at least a portion of the photo-carriers from the absorption region and to amplify the portion of the photo-carriers; an interface-dopant region formed in the substrate between the absorption region and the amplification region; a buffer layer formed between the absorption region and the interface-dopant region; one or more field-control regions formed between the absorption region and the interface-dopant region and at least partially surrounding the buffer layer; and a buried-dopant region formed in the substrate and separated from the absorption region, where the buried-dopant region is configured to collect at least a portion of the amplified portion of the photo-carriers from the amplification region.

An optical sensing apparatus including: a substrate including a first material; an absorption region including a second material different from the first material; an amplification region formed in the substrate and configured to collect at least a portion of the photo-carriers from the absorption region and to amplify the portion of the photo-carriers; an interface-dopant region formed in the substrate between the absorption region and the amplification region; a buffer layer formed between the absorption region and the interface-dopant region; one or more field-control regions formed between the absorption region and the interface-dopant region and at least partially surrounding the buffer layer; and a buried-dopant region formed in the substrate and separated from the absorption region, where the buried-dopant region is configured to collect at least a portion of the amplified portion of the photo-carriers from the amplification region.

An optical device includes a nanostructure body which induces surface plasmon resonance when irradiated with light, an alloy layer which is in contact with the nanostructure body and which has a lower work function than the nanostructure body, and an n-type semiconductor which is in Schottky contact with the alloy layer. The nanostructure body is composed of one selected from the group consisting of elemental metals, alloys, metal nitrides, and conductive oxides. The alloy layer is composed of at least two metals.

A low bandgap absorber region (LBAR) used in a laser power converter (LPC). The laser power converter is comprised of one or more subcells on a substrate, wherein at least one of the subcells has an emitter and base, with the low bandgap absorber region coupled between the emitter and base. The emitter and base are comprised of a material with a bandgap higher than a wavelength of incident laser light, and the low bandgap absorber region is comprised of a material with a bandgap lower than the emitter and base. The emitter and base are transparent to the incident laser light, and the low bandgap absorber region absorbs the incident laser light and generates a current in response thereto, such that the current is controlled by the material and thickness of the low bandgap absorber region. The low bandgap absorber region is configured to produce a current balanced to the subcells connected in series.

A compound semiconductor device is disclosed. The compound semiconductor device comprises a substrate having at least a first doped region and at least a second doped region; a semiconductor layer disposed on the substrate; and a buffer layer located between said substrate and said semiconductor layer; wherein doping conditions of said first doped region and said second doped region are different from each other; wherein said semiconductor layer has different thicknesses on locations corresponding to said first doped region and said second doped region respectively, and is formed as a structure with difference in thickness.

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.

One aspect of the present invention relates to a photovoltaic cell. In one embodiment, the photovoltaic cell includes a first conductive layer, an N-doped semiconductor layer formed on the first conductive layer, a first silicon layer formed on the N-doped semiconductor layer, a nanocrystalline silicon (nc-Si) layer formed on a first silicon layer, a second silicon layer formed on the nc-Si layer, a P-doped semiconductor layer on the second silicon layer, and a second conductive layer formed on the P-doped semiconductor layer, where one of the first silicon layer and the second silicon layer is formed of amorphous silicon, and the other of the first silicon layer and the second silicon layer formed of polycrystalline silicon.

A solar cell is formed to have a silicon semiconductor substrate of a first conductive type; an emitter layer having a second conductive type opposite the first conductive type and formed on a first surface of the silicon semiconductor substrate; a back surface field layer having the first conductive type and formed on a second surface of the silicon semiconductor substrate opposite to the first surface; and wherein the emitter layer includes at least a first shallow doping area and the back surface field layer includes at least a second shallow doping area, and wherein a thickness of the first shallow doping area of the emitter layer is different from a thickness of the second shallow doping area of the back surface field layer.

Methods of fabricating solar cell emitter regions using self-aligned implant and cap, and the resulting solar cells, are described. In an example, a method of fabricating an emitter region of a solar cell involves forming a silicon layer above a substrate. The method also involves implanting, through a stencil mask, dopant impurity atoms in the silicon layer to form implanted regions of the silicon layer with adjacent non-implanted regions. The method also involves forming, through the stencil mask, a capping layer on and substantially in alignment with the implanted regions of the silicon layer. The method also involves removing the non-implanted regions of the silicon layer, wherein the capping layer protects the implanted regions of the silicon layer during the removing. The method also involves annealing the implanted regions of the silicon layer to form doped polycrystalline silicon emitter regions.

Embodiments of the present disclosure relate to the field of solar cell technologies, and provide a solar cell, a method for preparing the same, and a photovoltaic module. The solar cell includes an N-type silicon substrate including a front surface and a rear surface opposite to the front surface. The front surface includes a plurality of pyramid structures, the rear surface includes a plurality of grooves, and some of the plurality of grooves are sequentially arranged along one arrangement direction. The solar cell includes a passivation layer formed over the front surface, a tunneling dielectric layer formed over the rear surface, and a doped conductive layer formed over the tunneling dielectric layer. Embodiments of the present disclosure at least help improve the photoelectric conversion efficiency of the solar cell by changing a morphology of the rear surface of the N-type silicon substrate.