Abstract:
An object of the present invention is to provide a group III-V compound semiconductor photo detector comprising an absorption layer having a group III-V compound semiconductor layer containing Sb as a group V constituent element, and an n-type InP window layer, resulting in reduced dark current. The InP layer 23 grown on the absorption layer 23 contains antimony as impurity, due to the memory effect with antimony which is supplied during the growth of a GaAsSb layer of the absorption layer 21. In the group III-V compound semiconductor photo detector 11, the InP layer 23 contains antimony as impurity and is doped with silicon as n-type dopant. Although antimony impurities in the InP layer 23 generate holes, the silicon contained in the InP layer 23 compensates for the generated carriers. As a result, the second portion 23d of the InP layer 23 has sufficient n-type conductivity.
Abstract:
Solar cell array assemblies or modules and methods of making and using such solar cell array assemblies or modules, having discrete predefined pressure sensitive adhesive (PSA) regions thereon. In certain embodiments, the solar cell array modules may be conveniently mounted on the surface of a panel of a space vehicle or satellite with the discrete predefined PSA regions.
Abstract:
In this photoelectric conversion element wherein group III-IV compound semiconductor single crystals containing zinc as an impurity are used as a substrate, the substrate is increased in size without lowering conversion efficiency. A heat-resistant crucible is filled with raw material and a sealant, and the raw material and sealant are heated, thereby melting the raw material into a melt, softening the encapsulant, and covering the melt from the top with the encapsulant. The temperature inside the crucible is controlled such that the temperature of the top of the encapsulant relative to the bottom of the encapsulant becomes higher in a range that not equal or exceed the temperature of bottom of the encapsulant, and seed crystal is dipped in the melt and pulled upward with respect to the melt, thereby growing single crystals from the seed crystal. Thus, a large compound semiconductor wafer that is at least two inches in diameter and has a low dislocation density of 5,000 cm -2 can be obtained, despite having a low average zinc concentration of 5 × 10 17 cm -3 to 3 × 10 18 cm -3 , at which a crystal hardening effect does not manifest.
Abstract:
The invention relates to a multi-junction solar cell having at least three p-n junctions, which contains a back-side sub-cell having at least one p-n junction and containing GaSb and a front-side sub-cell having at least two p-n junctions and which is characterised in that the back-side sub-cell has a lattice constant that is greater than the lattice constant of the front-side sub-cell by ≥ 2%, in particular by > 4%, and the two sub-cells are connected to one another by means of an optically transparent and electrically conductive wafer-bond connection. The multi-junction solar cell achieves high absorption up to the band gap energy of the bottommost sub-cell containing GaSb and a photovoltage that is increased in comparison with multi-junction solar cells of the prior art. The invention further relates to methods for producing the multi-junction solar cell according to the invention and uses of the multi-junction solar cell according to the invention.
Abstract:
A semiconductor light detection or photovoltaic device fabrication technique is provided in which the cap (3) etch and anti-reflection coating (11) steps are performed in a single, self-aligned lithography module.
Abstract:
The present invention relates to a technique of producing spontaneous radiation sources on the basis on A III B V semiconductor compounds for the spectral range of 2.6 - 4.7 µm, and to a technology of producing photosensitive structures for the spectral range of 2.0 - 4.7 µm. In the first embodiment, the heterostructure comprises a substrate containing InAs, a barrier layer which contains InSbP and which is arranged on the substrate, and an active layer which contains InAsSbP and which is arranged on the barrier layer. Light-emitting diodes produced on the basis of the first embodiment of the heterostructure emit at a wavelength in the range of 2.6 - 3.1 µm. In the second embodiment, the heterostructure comprises a substrate containing InAs, an active area which contains InAsSb and which is arranged on the substrate, and a barrier layer which contains InSbP and which is arranged on the active area. The active area can comprise a InAsSb bulk active layer, InAs/InAsSb quantum wells or a GaInAs/InAsSb strained superlattice. Light-emitting diodes produced on the basis of the second embodiment of the heterostructure emit at a wavelength in the range of 3.1- 4.7pm, and photodiodes have broadband sensitivity in the range of 2.0 - 4.7 µm. In the method of producing a heterostructure, tert-butylarsine is used as a source of arsenic, and tert-butylphosphine is used as a source of phosphorus.
Abstract:
Photodetectors, methods of fabricating the same, and methods using the same to detect radiation are described. A photodetector can include a first electrode, a light sensitizing layer, an electron blocking/tunneling layer, and a second electrode. Infrared-to-visible upconversion devices, methods of fabricating the same, and methods using the same to detect radiation are also described. An Infrared-to-visible upconversion device can include a photodetector and an OLED coupled to the photodetector.
Abstract:
A method for manufacturing a semiconductor device and semiconductor manufactured thereby, comprising growing, from a seed island mesa, an abrupt hetero-junction comprising a semiconductor crystal with few crystal defects on a dissimilar substrate (50) that can be used as light emitting and photovoltaic devices.