The invention relates to a photoactive semiconductor component, especially a photovoltaic solar cell, having a semiconductor substrate, a carbon-containing SiC layer disposed indirectly upon a surface of the semiconductor substrate, and a passivating intermediate layer disposed indirectly or directly between the SiC layer and semiconductor substrate, and a metallic contact connection disposed indirectly or directly upon a side of the SiC layer facing away from the passivating intermediate layer and in electrically conductive connection with the SiC layer, where the SiC layer has p-type or n-type doping, which is characterized in that the SiC layer partly has a partly amorphous structure and partly has a crystalline structure.

A method for producing a mono-crystalline sheet includes providing at least two aperture elements forming a gap in between; providing a molten alloy including silicon in the gap; providing a gaseous precursor medium comprising silicon in the vicinity of the molten alloy; providing a silicon nucleation crystal in the vicinity of the molten alloy; and bringing in contact said silicon nucleation crystal and the molten alloy. A device for producing a mono-crystalline sheet includes at least two aperture elements at a predetermined distance from each other, thereby forming a gap, and being adapted to be heated for holding a molten alloy including silicon by surface tension in the gap between the aperture elements; a precursor gas supply supplies a gaseous precursor medium comprising silicon in the vicinity of the molten alloy; and a positioning device for holding and moving a nucleation crystal in the vicinity of the molten alloy.

It is an object to reduce the region of a photoelectric conversion element which light does not reach, to suppress deterioration of power generation efficiency, and to suppress manufacturing cost of a voltage conversion element. The present invention relates to a transmissive photoelectric conversion device which includes a photoelectric conversion element including an n-type semiconductor layer, an intrinsic semiconductor layer, and a p-type semiconductor layer; a voltage conversion element which is overlapped with the photoelectric conversion element and which includes an oxide semiconductor film for a channel formation region; and a conductive element which electrically connects the photoelectric conversion element and the voltage conversion element. The photoelectric conversion element is a solar cell. The voltage conversion element includes a transistor having a channel formation region including an oxide semiconductor film. The voltage conversion element is a DC-DC converter.

Techniques for enhancing the absorption of photons in semiconductors with the use of microstructures are described. The microstructures, such as pillars and/or holes, effectively increase the effective absorption length resulting in a greater absorption of the photons. Using microstructures for absorption enhancement for silicon photodiodes and silicon avalanche photodiodes can result in bandwidths in excess of 10 Gb/s at photons with wavelengths of 850 nm, and with quantum efficiencies of approximately 90% or more.

Techniques for enhancing the absorption of photons in semiconductors with the use of microstructures are described. The microstructures, such as pillars and/or holes, effectively increase the effective absorption length resulting in a greater absorption of the photons. Using microstructures for absorption enhancement for silicon photodiodes and silicon avalanche photodiodes can result in bandwidths in excess of 10 Gb/s at photons with wavelengths of 850 nm, and with quantum efficiencies of approximately 90% or more.

A photodiode and a related method of manufacture are disclosed. The photodiode includes a transfer gate and a floating diffusion adjacent to the transfer gate. In addition, the photodiode includes an upper terminal; an intrinsic semiconductor region in contact with the upper terminal, the intrinsic semiconductor region in a trench in a substrate adjacent to the transfer gate; and a lower terminal in contact with the intrinsic semiconductor region. An insulator layer is along an entirety of a sidewall of the intrinsic semiconductor region and between the intrinsic semiconductor region and the transfer gate. A p-type well may also optionally be between the insulator layer and the transfer gate.

Provided is a photoelectric detector, comprising: a silicon layer (110), the silicon layer (110) comprising a first-doping-type doped region (111); a germanium layer (120) in contact with the silicon layer (110), the germanium layer (120) comprising a second-doping-type doped region (121); and a silicon nitride waveguide (130), the silicon nitride waveguide (130) being arranged surrounding the germanium layer (120) along the extension directions of at least three side walls of the germanium layer (120), wherein the silicon nitride waveguide (130) is used for transmitting an optical signal and coupling the optical signal to the germanium layer (120), and the germanium layer (120) is used for detecting the optical signal and converting the optical signal into an electrical signal.

Provided is a photoelectric detector, comprising: a silicon layer (110), the silicon layer (110) comprising a first-doping-type doped region (111); a germanium layer (120) in contact with the silicon layer (110), the germanium layer (120) comprising a second-doping-type doped region (121); and a silicon nitride waveguide (130), the silicon nitride waveguide (130) being arranged surrounding the germanium layer (120) along the extension directions of at least three side walls of the germanium layer (120), wherein the silicon nitride waveguide (130) is used for transmitting an optical signal and coupling the optical signal to the germanium layer (120), and the germanium layer (120) is used for detecting the optical signal and converting the optical signal into an electrical signal.

A lateral photodetector may include a high e-field multiplication region. The high e-field multiplication region may be provided by lightly p doping areas adjacent to or near an n-finger of the photodetector. The high e-field multiplication region may also be provided by providing a slightly conducting horizontal plane between p-fingers and n-fingers of the photodetector. The photodetector may be grown on a silicon substrate, which is etched to form a gap to allow for light to reach the photodetector through the gap.

A tandem photovoltaic device includes: an upper cell unit, a lower cell unit and a tunnel junction positioned between the upper cell unit and the lower cell unit; the tunnel junction includes an upper transport layer, a lower transport layer, and an intermediate layer positioned between the upper transport layer and the lower transport layer, the intermediate layer is an ordered defect layer, or, the intermediate layer is a continuous thin layer, or, the intermediate layer includes a first layer in contact with the lower transport layer and a second layer in contact with the upper transport layer; a doping concentration of the first layer is 10-10,000 times of a doping concentration of the lower transport layer, and the doping concentration of the first layer is less than 10.sup.21 cm.sup.3; a doping concentration of the second layer is 10-10,000 times of a doping concentration of the upper transport layer.