Abstract: A semiconductor heat sink made of a first material including a plurality of spaced-apart depressions and an area surrounding the depressions filled with one or more materials having a heat conductivity greater than the first material.

Abstract: A laser diode including a double heterostructure comprising a top layer, a buffer layer formed on a substrate, and an intrinsic active layer formed between the top layer and the buffer layer. The top layer and the buffer layer have opposite types of conductivity. The active layer has a bandgap smaller than that of the buffer layer or the top layer. The double heterostructure includes Ge, SiGe, GeSn, and/or SiGeSn materials.

Abstract: A high-temperature power module integrated with an optically galvanic isolated gate driver. The power module includes one or more galvanic isolated gate driver boards, where each galvanic isolated gate driver board includes an optocoupler configured to transfer electrical signals between two isolated circuitry by using light. Furthermore, each galvanic isolated gate driver board includes a gate driver connected to the optocoupler, where the gate driver includes a power amplifier that receives a signal and produces a current drive input for a gate of a transistor.

Abstract: A high temperature optoelectronic isolator for power electronics operating above 250 degrees Celcius.

Abstract: An integrated microwave photonics (IMWP) apparatus is provided using sapphire as a platform. The IMWP apparatus includes: a sapphire substrate having a step-terrace surface; and a III-V stack layer epitaxially grown on the sapphire substrate. The III-V stack layer includes: a first III-V layer disposed on the sapphire substrate; a low temperature (LT) III-V buffer layer disposed on the first III-V layer; multiple second III-V layers disposed and stacked on the LT III-V buffer layer; a third III-V layer disposed on the second III-V layers; a III-V quantum well layer disposed on the third III-V layers; and a fourth III-V layer disposed on the III-V quantum well layer. The second III-V layers are respectively annealed. A growth temperature of the LT III-V layer and a growth temperature of the III-V quantum well layer are lower than a growth temperature of each of the first, second, third and fourth III-V layers.

Abstract: A laser diode including a double heterostructure comprising a top layer, a buffer layer formed on a substrate, and an intrinsic active layer formed between the top layer and the buffer layer. The top layer and the buffer layer have opposite types of conductivity. The active layer has a bandgap smaller than that of the buffer layer or the top layer. The double heterostructure includes Ge, SiGe, GeSn, and/or SiGeSn materials.

Abstract: High-performance long-lifetime charge-separation photodetectors are provided. A new device design is described based on novel band structure engineering of semiconductor materials for photodetectors, such as photosensors, solar cells, and thermophotovoltaic devices. In an exemplary aspect, photodetectors described herein include a charge-separated photo absorber region. This comprises a semiconductor with a band structure that has an indirect fundamental bandgap, with a direct bandgap (?-? transition) only slightly above the indirect fundamental bandgap (L- or X-? transitions) (e.g., approximately equal to or larger than an energy of a product of the Boltzmann constant (kB), and temperature (T), with kBT=26 millielectron-volts (meV) at room temperature). This design not only improves photogenerated-carrier lifetime (similar to indirect bandgap semiconductors), but also maintains a strong absorption coefficient (similar to direct bandgap semiconductors).

Abstract: A semiconductor device made of one or more one-dimensional chains of atoms. The atoms form covalent bonds along the chain with no dangling bonds except at both ends of the chain.

Abstract: A semiconductor heat sink made of a first material including a plurality of spaced-apart depressions and an area surrounding the depressions filled with one or more materials having a heat conductivity greater than the first material.

Abstract: A semiconductor device made of one or more one-dimensional chains of atoms. The atoms form covalent bonds along the chain with no dangling bonds except at both ends of the chain.

Abstract: Heteroepitaxial methods are described herein for the growth of germanium-tin alloy layers directly on silicon substrates. A method of heteroeptiaxial growth of a germanium-tin alloy layer comprises placing a silicon substrate in a cold wall ultra-high vacuum chemcial vapor deposition chamber and depositing the germanium-tin alloy layer directly on the silicon substrate from a gaseous mixture in the deposition chamber, the gaseous mixture comprising a germanium source and a tin source.

Abstract: The present invention provides semiconductor structures comprising a substrate and at least three III-V and/or II-VI multi junction building blocks, each comprising a p-n junction having at least two alloy layers, formed over the substrate, provided at least one multi-junction building block comprises II-VI alloy layers. Further described are methods for preparing semiconductor structures utilizing a sacrificial or etch-stop ternary III-V alloy layer over an III-V substrate.