A device includes a diode. The anode of the diode includes first, second, and third areas. The first area partially covers the second area and has a first doping level greater than a second doping level of the second area. The second area partially covers the third area and has the second doping level greater than a third doping level of the third area. A first insulating layer partially overlaps the first and second areas.

A transient voltage suppressor is disclosed that includes an electrode, a substrate disposed on the electrode, the substrate having a first doping, an epitaxial layer disposed on the substrate, the epitaxial layer having a second doping that is different from the first doping, a channel formed in the epitaxial layer having a width W, a length L and a plurality of curved regions, the channel forming a plurality of adjacent sections, the channel having a third doping that is different from the first doping and the second doping and a metal layer formed on top of the channel and contained within the width W of the channel.

A p-type semiconductor region is formed in a front surface side of an n-type semiconductor substrate. An n-type field stop (FS) region including protons as a donor is formed in a rear surface side of the semiconductor substrate. A concentration distribution of the donors in the FS region include first, second, third and fourth peaks in order from a front surface to the rear surface. Each of the peaks has a peak maximum point, and peak end points formed at both sides of the peak maximum point. The peak maximum points of the first and second peaks are higher than the peak maximum point of the third peak. The peak maximum point of the third peak is lower than the peak maximum point of the fourth peak.

A semiconductor device includes a semiconductor part, first and second electrodes. The semiconductor part is provided between the first and second electrodes. A method of manufacturing the device includes forming the first electrode covering a back surface of a wafer after the second electrode is formed on a front surface of the wafer; forming a first groove by selectively removing the first electrode; and dividing the wafer by forming a second groove at the front surface side. The wafer includes a region to be the semiconductor part; and the first and second grooves are provided along a periphery of the region. The first groove is in communication with the first groove. The second groove has a width in a direction along the front surface of the wafer, the width of the first groove being narrower than a width of the first groove in the same direction.

A high voltage edge termination structure for a power semiconductor device is provided. The high voltage edge termination structure comprises a semiconductor body of a first conductive type, a JTE region of a second conductive type, a heavily doped channel stop region of the first conductive type, and a plurality of field plates. The JTE region is formed in the semiconductor body, wherein the JTE region is adjacent to an active region of the power semiconductor device. The heavily doped channel stop region is formed in the semiconductor body, wherein the heavily doped channel stop region is spaced apart from the JTE region. The plurality of field plates is formed on the JTE region.

A semiconductor device includes: an N.sup.− drift layer of a first conductivity type formed in the semiconductor substrate; a P base layer formed on the N.sup.− drift layer; and an N buffer layer of the first conductivity type formed under the N.sup.− drift layer and higher in peak impurity concentration than the N.sup.− drift layer. The N buffer layer includes: a first buffer layer in which a trap level derived from lattice defect is not detected by a photoluminescence method; and a second buffer layer provided between the first buffer layer and the N.sup.− drift layer and in which two types of trap levels derived from lattice defect are detected by the photoluminescence method.

Apparatus and methods relating to heterolithic microwave integrated circuits HMICs are described. An HMIC can include different semiconductor devices formed from different semiconductor systems in different regions of a same substrate. An HMIC can also include bulk regions of low-loss electrically-insulating material extending through the substrate and located between the different semiconductor regions. Passive RF circuit elements can be formed on the low-loss electrically-insulating material.

A power semiconductor device includes a diode part disposed in a first region of a substrate, a junction field effect transistor (JFET) part disposed in a second region adjacent to the first region of the substrate, an anode terminal disposed on the first region of the substrate, and a cathode terminal disposed on the second region of the substrate.

An electron extraction type free-wheeling diode device and a preparation method thereof are provided by the present disclosure, and more than one first structures for increasing the density of electron extraction pathways are provided on a N-type drift region. Each of the first structures includes a lightly doped P-type base region, a heavily doped N-type emitter region located on the lightly doped P-type base region, a P-type trench anode region, and a trench region located on the P-type trench anode region. The barrier height of the punch-through NPN triode can be tuned in a wide range, which has beneficial effects on soft and fast adjustment of the reverse recovery process.

A semiconductor device includes a semiconductor layer of a first conductivity type having a device forming region and an outside region, an impurity region of a second conductivity type formed in a surface layer portion of a first main surface in the device forming region, a field limiting region of a second conductivity type formed in the surface layer portion in the outside region and having a impurity concentration higher than that of the impurity region, and a well region of a second conductivity type formed in a region between the device forming region and the field limiting region in the surface layer portion in the outside region, having a bottom portion positioned at a second main surface side with respect to bottom portions of the impurity region and the field limiting region, and having a impurity concentration higher than that of the impurity region.