Abstract:
A single junction solar cell may be manufactured with a material having multiple bands. That is, a single semiconductor with several absorption edges that absorb photons from different parts of the solar spectrum may be constructed. The different absorption edges may be created by splitting a conduction band of the solar cell material into multiple intermediate sub-bands. The solar cell may include a photovoltaic material deposited on a substrate, in which the photovoltaic material is a III-V semiconductor alloy, such as AlGaNAs, AlGaAsNSb, or AlInGaNAsBi.
Abstract:
TA photo detection device, including a substrate, a band-pass filter layer formed over the substrate, a light absorption layer formed over the band-pass filter layer, a Schottky layer formed on a portion of the light absorption layer, a first electrode layer formed on a portion of the Schottky layer, and a second electrode layer formed on the light absorption layer and spaced apart from the Schottky layer.
Abstract:
A light detection device includes a substrate, a buffer layer disposed on the substrate, a first band gap change layer disposed on a portion of the buffer layer, a light absorption layer disposed on the first band gap change layer, a Schottky layer disposed on a portion of the light absorption layer, and a first electrode layer disposed on a portion of the Schottky layer.
Abstract:
Multijunction solar cells having at least four subcells are disclosed, in which at least one of the subcells comprises a base layer formed of an alloy of one or more elements from group III on the periodic table, nitrogen, arsenic, and at least one element selected from the group consisting of Sb and Bi, and each of the subcells is substantially lattice matched. Methods of manufacturing solar cells and photovoltaic systems comprising at least one of the multijunction solar cells are also disclosed.
Abstract:
The present invention relates to a UV photodetector having a high sensitivity and a low dark current. The object of the present invention is to specify a UV photodetector that has a high sensitivity and a low dark current. According to the invention, the fingers of the first electrode structure and the fingers of the second electrode structure have a cover layer made of a second semiconducting material, wherein the cover layer is arranged on the absorber layer and directly contacts the absorber layer in the region of the fingers, and the first semiconducting material and the second semiconducting material are designed in such a manner that a two-dimensional electron gas (2DEG) is formed at the boundary layer between the absorber layer and the cover layer in the region of the fingers.
Abstract:
A method for manufacturing a semiconductor thin film device includes: forming a buffer layer on an Si (111) substrate and a single crystal semiconductor layer on the buffer layer; forming an island including the semiconductor layer, buffer layer, and a portion of the substrate; forming a coating layer on the island; etching the substrate along its Si (111) plane to release the island from the substrate, the coating layer serving as a mask; and bonding the released island to another substrate, a released surface of the released island contacting the another substrate. A semiconductor device includes a single crystal semiconductor layer other than Si, which has a semiconductor device formed on a front surface of an Si (111) layer lying in a (111) plane. The layer is bonded to another substrate with a back surface contacting the another substrate or a bonding layer formed on the another substrate.
Abstract:
Dilute nitride III-V semiconductor materials may be formed by substituting As atoms for some N atoms within a previously formed nitride material to transform at least a portion of the previously formed nitride into a dilute nitride III-V semiconductor material that includes arsenic. Such methods may be employed in the fabrication of photoactive devices, such as photovoltaic cells and photoemitters. The methods may be carried out within a deposition chamber, such as a metalorganic chemical vapor deposition (MOCVD) or a vapor phase epitaxy (HVPE) chamber.
Abstract:
A photovoltaic device including a single junction solar cell provided by an absorption layer of a type IV semiconductor material having a first conductivity, and an emitter layer of a type III-V semiconductor material having a second conductivity, wherein the type III-V semiconductor material has a thickness that is no greater than 50 nm.
Abstract:
A lattice-matched solar cell having a dilute nitride-based sub-cell has exponential doping to thereby control current-carrying capacity of the solar cell. Specifically a solar cell with at least one dilute nitride sub-cell that has a variably doped base or emitter is disclosed. In one embodiment, a lattice matched multi junction solar cell has an upper sub-cell, a middle sub-cell and a lower dilute nitride sub-cell, the lower dilute nitride sub-cell having doping in the base and/or the emitter that is at least partially exponentially doped so as to improve its solar cell performance characteristics. In construction, the dilute nitride sub-cell may have the lowest bandgap and be lattice matched to a substrate, the middle cell typically has a higher bandgap than the dilute nitride sub-cell while it is lattice matched to the dilute nitride sub-cell. The upper sub-cell typically has the highest bandgap and is lattice matched to the adjacent sub-cell. In further embodiments, a multi junction solar cell according to the invention may comprise four, five or more sub-cells in which the one or more sub-cells may each comprise exponentially doped dilute nitride alloys.