According to one embodiment, a semiconductor device includes a first electrode, a second electrode, a first semiconductor region, a second semiconductor region, a third semiconductor region, and a fourth semiconductor region. The first semiconductor region is provided between the first and second electrodes. The second semiconductor region is provided between the first semiconductor region and the second electrode. The third semiconductor region is provided between the first semiconductor region and the second electrode, is provided beside the second semiconductor region in a second direction crossing a first direction from the first electrode toward the second electrode, and a portion of the first semiconductor region is positioned between the third and second semiconductor regions. The fourth semiconductor region is provided between the portion of the first semiconductor region and the second electrode and has a greater impurity concentration than the second and third semiconductor regions.

A material structure for silicon-based gallium nitride microwave and millimeter-wave devices and a manufacturing method thereof are provided. The material structure includes: a silicon substrate; a dielectric layer of high thermal conductivity, disposed on an upper surface of the silicon substrate, and an uneven first patterned interface being formed between the dielectric layer and the silicon substrate; a buffer layer, disposed on an upper surface of the dielectric layer, and an uneven second patterned interface being formed between the buffer layer and the dielectric layer; a channel layer, disposed on an upper surface of the buffer layer; and a composite barrier layer, disposed on an upper surface of the channel layer. In the material structure, the uneven patterned interfaces increase contact areas of the interfaces, a thermal boundary resistance and a thermal resistance of device are reduced, and a heat dissipation performance of device is improved.

The present description concerns a method of manufacturing a first wafer, intended to be assembled to a second wafer by molecular bonding, including the successive steps of: forming a stack of layers at the surface of a substrate; and successive chemical etchings of the edges of said layers from the layer of the stack most distant from the substrate, across a smaller and smaller width.

A semiconductor device includes a substrate; a well region of a first-conductivity-type, disposed in the substrate; a first impurity region of a first-conductivity-type disposed in the well region; a second impurity region of the second-conductivity-type disposed in the well region, the second-conductivity-type being opposite to the first-conductivity-type; a third impurity region disposed in the well region, a portion of the first impurity region overlapping a first portion of the third impurity region, a portion of the second impurity region overlapping a second portion of the third impurity region, and a third portion of the third impurity region being disposed between the first impurity region and the second impurity region; and a fourth impurity region and a barrier layer disposed in the substrate, the fourth impurity region and the barrier layer enclosing the well region from around and below, respectively.

A method for forming a semiconductor device includes incorporating first dopant atoms of a first conductivity type into a semiconductor substrate to form a first doping region of the first conductivity type. Further, the method includes forming an epitaxial semiconductor layer on the semiconductor substrate and incorporating second dopant atoms of a second conductivity type before or after forming the epitaxial semiconductor layer to form a second doping region including the second conductivity type adjacent to the first doping region so that a pn-junction is located between the first doping region and the second doping region. The pn-junction is located in a vertical distance of less than 5 μm to an interface between the semiconductor substrate and the epitaxial semiconductor layer. Additionally, the method includes thinning the semiconductor substrate based on a self-aligned thinning process. The self-aligned thinning process is self-controlled based on the location of the pn-junction.

A semiconductor device includes: a first conductive type semiconductor device; a first conductive type drift region formed by epitaxial growth on the semiconductor substrate; a plurality of first conductive type vertical implantation regions formed by multistage ion implantation in the drift region, the vertical implantation regions having a prescribed vertical implantation width and a prescribed drift region width; an anode electrode disposed on the front surface of the drift region opposite to the semiconductor substrate, the anode electrode being in Schottky contact with the drift region and in ohmic contact with the first conductive type vertical implantation regions; and a cathode electrode disposed on the rear surface of the semiconductor substrate opposite to the drift region, the cathode electrode being in ohmic contact with the semiconductor substrate.

A method for making a hydrophobic biosensing device includes forming alternating layers over a top and sides of a fin on a dielectric layer to form a stack of layers. The stack of layers are planarized to expose the top of the fin. The fin and every other layer are removed to form a cathode group of fins and an anode group of fins. A hydrophobic surface on the two groups of fins.

A first region is formed by injecting a first condition type first dopant into a surface layer portion of an IGBT section of a semiconductor substrate. A second region is formed by injecting a second condition type second dopant into a region of the IGBT section shallower than the first region. An amorphous third region is formed by injecting the first conduction type third dopant into a surface layer portion of a diode section at a concentration higher than that of the second dopant. Thereafter, the IGBT section and the diode section are laser-annealed under conditions in which the third region is partially melted and the first dopant is activated. Subsequently, a surface layer portion which is shallower than the second injection region in the entire region of the IGBT section and the diode section is melted and crystallized by annealing the IGBT section and the diode section.

A semiconductor device includes an N-type silicon carbide layer, a P-type region, an N-type source region, a P-type contact region, a gate insulating film, a gate electrode, and a source electrode on the front surface side of an N-type silicon carbide substrate. A drain electrode is located on the back surface of the N-type silicon carbide substrate. A life time killer introduction region is located along an entire interface of the N-type silicon carbide layer and the bottom face of the P-type region. The life time killer is introduced by implanting helium or protons from the back surface side of the N-type silicon carbide substrate after forming a surface structure of an element on the front surface side of the N-type silicon carbide substrate and before forming the drain electrode.

A diode device of a transient voltage suppressor (TVS) is disclosed. The diode device includes a substrate, a first well, a second well, a first electrode and a second electrode. The substrate has a first surface. The first well is formed in the substrate and near the first surface. The second well is formed in the substrate and near the first surface. There is a gap between the first well and the second well. The first electrode is electrically connected with the first well. The second electrode is electrically connected with the second well. A current path is formed from the first electrode, the first well, the substrate, the second well to the second electrode. The current path passes through a plurality of PN junctions to form an equivalent circuit having a plurality of equivalent capacitances coupled in series.