There is provided a quantum dot solar cell having a high optical absorption coefficient. The quantum dot solar cell includes a quantum dot layer 3 including a plurality of quantum dots 1, wherein the quantum dot layer 3 includes a first quantum dot layer 3A having an index /x of 5% or more, wherein x is an average particle size, and is a standard deviation. The quantum dot layer 3 also includes a second quantum dot layer 3B that is provided on the light entrance surface 3b and/or the light exit surface 3c of the first quantum dot layer 3A and has an average particle size and an index /x smaller than those of the first quantum dot layer 3A.

A method for texturing silicon includes loading a silicon wafer into a vacuum chamber, heating the silicon wafer and thermal cracking a gas to generate cracked sulfur species. The silicon wafer is exposed to the cracked sulfur species for a time duration in accordance with a texture characteristic needed for a surface of the silicon wafer.

The disclosure provides a photoelectric detector. The photoelectric detector includes a waveguide layer, an absorption layer, and a cladding material. The absorption layer is located on the waveguide layer or at least partially embedded in the waveguide layer. The cladding material covers top portions and side walls of the waveguide layer and the absorption layer, at least one end surface of the photoelectric detector is a light incident surface, and light energy absorbed by a portion of the absorption layer adjacent to the light incident surface is smaller than light energy absorbed by other portions of the absorption layer.

A fin tunnel field effect transistor includes a seed region and a first type region disposed above the seed region. The first type region includes a first doping. The fin tunnel field effect transistor includes a second type region disposed above the first type region. The second type region includes a second doping that is opposite the first doping. The fin tunnel field effect transistor includes a gate insulator disposed above the second type region and a gate electrode disposed above the gate insulator. A method for forming an example fin tunnel field effect transistor is provided.

Integrated circuits and methods of producing such integrated circuits are provided. In an exemplary embodiment, a method of producing an integrated circuit includes forming an upper interlayer dielectric overlying an optical modulator and a photodetector, where the photodetector has a shoulder and a plug. An etch stop is formed overlying the upper interlayer dielectric. The etch stop is a first, second, and third distance from an uppermost surface of the optical modulator, the shoulder, and the plug, respectively, where the first, second, and third distances are all different from each other. A first, second, and third contact are formed through the upper interlayer dielectric, where the first, second and third contacts are in electrical communication with the optical modulator, the shoulder, and the plug, respectively.

An avalanche photodiode includes a GeOI substrate; an IGe absorption layer configured to absorb an optical signal and generate a photo-generated carrier; a first p-type SiGe layer, a second p-type SiGe layer, a first SiGe layer, and a second SiGe layer, where a Si content in any one of the SiGe layers is less than or equal to 20%; a first SiO.sub.2 oxidation layer and a second SiO.sub.2 oxidation layer; a first taper type silicon Si waveguide layer and a second taper type silicon Si waveguide layer; a heavily-doped n-type silicon Si multiplication layer; and anode electrodes and a cathode electrode.

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.

Techniques for enhancing the absorption of photons in semiconductors with the use of microstructures are described. The microstructures, such as holes, effectively increase the 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. Their thickness dimensions allow them to be conveniently integrated on the same Si chip with CMOS, BiCMOS, and other electronics, with resulting packaging benefits and reduced capacitance and thus higher speeds.

An optoelectronic device for detecting electromagnetic radiation includes a body of semiconductor material. A first region and a second region that form a junction are provided within the body. A recess extends into the body and is delimited by side arranged transverse to a main surface of the body. The junction is exposed by the sidewall to coupled electromagnetic radiation received in the recess into a photodiode formed by the junction.

Photovoltaic systems and methods for optimizing the harvesting of solar energy are disclosed. A photovoltaic (PV) system includes: a solar panel module. The solar panel module comprises: a plurality of solar cell arrays, wherein each array comprises a grouping of solar cells; and a tubular panel. The plurality of solar cell arrays are arranged along an inside surface of the panel. At least an upper portion of the panel slopes inward such that the panel has a substantially funnel-shaped geometry. The solar cell arrays are arranged in a C-ring pattern. A first solar cell array is separated from a second solar cell array by a predetermined distance. The area between the solar cell arrays is coated with a reflective material to facilitate optimal reflection of incident sunlight back to the solar cells. Recycling of incident light is facilitated within the tube. The light can be intermittently or continuously recycled.