A monolithic multiple solar cell includes at least three partial cells, with a semiconductor mirror placed between two partial cells. The aim of the invention is to improve the radiation stability of said solar cell. For this purpose, the semiconductor mirror has a high degree of reflection in at least one part of a spectral absorption area of the partial cell which is arranged above the semiconductor mirror and a high degree of transmission within the spectral absorption range of the partial cell arranged below the semiconductor mirror.

Techniques are disclosed for providing an optical sensor that can be used for wind sensing and an optical scope. The optical sensor can include a photodiode, an electrical switch, a trans-impedance amplifier (TIA), and a capacitive trans-impedance amplifier (CTIA), enabling the optical sensor to perform both wind-sensing and range-finding functions. Some embodiments may include some or all of these components in an application-specific integrated circuit (ASIC), depending on desired functionality.

A method of forming a layered OP material is provided, where the layered OP material comprises an OPGaAs template, and a layer of GaP on the OPGaAs template. The OPGaAs template comprises a patterned layer of GaAs having alternating features of inverted crystallographic polarity of GaAs. The patterned layer of GaAs comprises a first feature comprising a first crystallographic polarity form of GaAs having a first dimension, and a second feature comprising a second crystallographic polarity form of GaAs having a second dimension. The layer of GaP on the patterned layer of GaAs comprises alternating regions of inverted crystallographic polarity that generally correspond to their underlying first and second features of the patterned layer of GaAs. Additionally, each of the alternating regions of inverted crystallographic polarity of GaP are present at about 100 micron thickness or more.

Photovoltaic devices including direct gap III-V absorber materials and operatively associated back structures enhance efficiency by enabling photon recycling. The back structures of the photovoltaic devices include wide bandgap III-V layers, highly doped (In)GaAs layers, patterned oxide layers and metal reflectors that directly contact the highly doped (In)GaAs layers through vias formed in the back structures. Localized ohmic contacts are formed in the back structures of the devices.

A uni-terminal transistor device is described. In one embodiment, an n-channel transistor having p-terminal characteristics comprises a first semiconductor layer having a discrete hole level; a second semiconductor layer having a conduction band whose minimum level is lower than that of the first semiconductor layer; a wide bandgap semiconductor barrier layer disposed between the first and the second semiconductor layers; a gate dielectric layer disposed above the first semiconductor layer; and a gate metal layer disposed above the gate dielectric layer and having an effective workfunction selected to position the discrete hole level below the minimum level of the conduction band of the second semiconductor layer for zero bias applied to the gate metal layer and to obtain p-terminal characteristics.

A photodiode includes a p-type ohmic contact and a p-type substrate in contact with the p-type ohmic contact. An intrinsic layer is formed over the substrate and including a III-V material. A transparent II-VI n-type layer is formed on the intrinsic layer and functions as an emitter and an n-type ohmic contact.

The present invention discloses a photo-detector comprising: an n-type photon absorbing layer of a first energy bandgap; a middle barrier layer, an intermediate layer is a semiconductor structure; and a contact layer of a third energy bandgap, wherein the layer materials are selected such that the first energy bandgap of the photon absorbing layer is narrower than that of said middle barrier layer; wherein the material composition and thickness of said intermediate layer are selected such that the valence band of the intermediate layer lies above the valence band in the barrier layer to create an efficient trapping and transfer of minority carriers from the barrier layer to the contact layer such that a tunnel current through the barrier layer from the contact layer to the photon absorbing layer is less than a dark current in the photo-detector and the dark current from the photon-absorbing layer to said middle barrier layer is essentially diffusion limited and is due to the unimpeded flow of minority carriers, thus reducing generation-recombination (GR) noise of the photo-detector. The principles of the present invention also apply to inverted polarity structures of the form pBp in which all the doping polarities and band alignments described above are reversed.

According to one aspect, the invention relates to an element for quantum photodetection of an incident radiation in a spectral band centered around a central wavelength .sub.0, having a front surface intended for receiving said radiation, and including: a stack of layers of semiconductor material forming a PN or PIN junction and including at least one layer made of an absorbent semiconductor material having a cut-off wavelength .sub.0>.sub.0, the stack of layers of semiconductor material forming a resonant optical cavity; and a structure for coupling the incident radiation with the optical cavity such as to form a resonance at the central wavelength .sub.0 allowing the absorption of more than 80% in the layer of absorbent semiconductor material at said central wavelength, and an absence of resonance at the radiative wavelength .sub.rad, wherein the radiative wavelength .sub.rad is the wavelength for which, at operating temperature, the radiative recombination rate is the highest.

According to one embodiment, a semiconductor photoreceiving device includes a substrate, a first structural layer provided on the substrate, in which light enters from the substrate side and in which a refractive index changes periodically, a semiconductor layer provided on the first structural layer and including an optical absorption layer, a reflective layer provided on the semiconductor layer, and a pair of electrodes configured to apply voltage to the optical absorption layer.

A monolithic multiple solar cell includes at least three partial cells, with a semiconductor mirror placed between two partial cells. The aim of the invention is to improve the radiation stability of said solar cell. For this purpose, the semiconductor mirror has a high degree of reflection in at least one part of a spectral absorption area of the partial cell which is arranged above the semiconductor mirror and a high degree of transmission within the spectral absorption range of the partial cell arranged below the semiconductor mirror.