A semiconductor device includes: a compound semiconductor layer having a first compound semiconductor layer and a second compound semiconductor layer having a higher melting point than the first compound semiconductor layer; and an insulation gate on the second compound semiconductor layer. The compound semiconductor layer further includes: a drift region; a source region; and a body region between the drift region and the source region. The insulation gate faces the body region. The body region bridges over both the first compound semiconductor layer and the second compound semiconductor layer.

A manufacturing method of a nitride semiconductor device includes: introducing a p type impurity into at least a part of an upper layer portion of a first nitride semiconductor layer to form a p type impurity introduction region; forming a second nitride semiconductor layer from an upper surface of the first nitride semiconductor layer so as to include the p type impurity introduction region; and performing an anneal treatment in a state where the second nitride semiconductor layer is formed on the first nitride semiconductor layer.

A silicon carbide epitaxial substrate includes a silicon carbide single crystal substrate and a silicon carbide layer. In a direction parallel to a central region, a ratio of a standard deviation of a carrier concentration of the silicon carbide layer to an average value of the carrier concentration of the silicon carbide layer is less than 5%. The average value of the carrier concentration is more than or equal to 1×10.sup.14 cm.sup.−3 and less than or equal to 5×10.sup.16 cm.sup.−3. In the direction parallel to the central region, a ratio of a standard deviation of a thickness of the silicon carbide layer to an average value of the thickness of the silicon carbide layer is less than 5%. The central region has an arithmetic mean roughness (Sa) of less than or equal to 1 nm. The central region has a haze of less than or equal to 50.

A VDMOS device and a manufacturing method therefor. The method comprises: forming a groove in a semiconductor substrate, wherein the groove comprises a first groove area, a second groove area and a third groove area communicating with the first groove area and the second groove area, and the width of the first groove area is greater than the widths of the second groove area and the third groove area; forming an insulation layer on the semiconductor substrate; forming a first polycrystalline silicon layer on the insulation layer; removing some of the first polycrystalline silicon layer; the first polycrystalline silicon layer forming in the first groove being used as a first electrode of a deep gate; removing all the insulation layer located on the surface of the semiconductor substrate and some of the insulation layer located in the groove; forming a gate oxide layer on the semiconductor substrate; forming a second polycrystalline silicon layer on the gate oxide layer; removing some of the second polycrystalline silicon layer; and the second polycrystalline silicon layer forming in the groove being used as a second electrode of a shallow gate.

Provided is a semiconductor device that can detect the cracking progress with high precision. A semiconductor device is formed using a semiconductor substrate, and includes an active region in which a semiconductor element is formed, and an edge termination region outside the active region. A crack detection structure is termed in the edge termination region of the semiconductor substrate. The crack detection structure includes: a trench formed in the semiconductor substrate and extending in a circumferential direction of the edge termination region; an inner-wall insulating film formed on an inner wall of the trench; an embedded electrode formed on the inner-wall insulating film and embedded into the trench; and a monitor electrode formed on the semiconductor substrate and connected to the embedded electrode.

A method forms a part of a power semiconductor device. The method includes homoepitaxially forming two silicon carbide layers on a first side of a silicon carbide substrate and forming a pattern of pits on a second side of the silicon carbide substrate. The two layers include a buffer layer, on the first side of the silicon carbide substrate, and have a same doping type of the silicon carbide substrate and a doping concentration equal to or greater than 10.sup.17 cm.sup.−3 in order to increase the quality of at least one subsequent SiC layer. The two layers include an etch stopper layer, being deposited on the buffer layer and has a same doping type as the buffer layer but a lower doping concentration in order to block a trenching process. The pattern of pits, obtained by electrochemical etching, extends completely thorough the silicon carbide substrate and the buffer layer.

A method for forming a superjunction transistor device includes: forming a plurality of semiconductor layers one on top of the other; implanting dopant atoms of a first doping type into each semiconductor layer to form first implanted regions in each semiconductor layer; implanting dopant atoms of a second doping type into each semiconductor layer to form second implanted regions in each semiconductor layer. Each of implanting the dopant atoms of the first and second doping types into each semiconductor layer includes forming a respective implantation mask on a respective surface of each semiconductor layer, and at least one of forming the first implanted regions and the second implanted regions in at least one of the semiconductor layers includes a tilted implantation process which uses an implantation vector that is tilted by a tilt angle relative to a normal of the respective horizontal surface of the respective semiconductor layer.

A silicon carbide (SiC) metal oxide semiconductor (MOS) power device is disclosed which includes an SiC drain semiconductor region, an SiC drift semiconductor region coupled to the SiC drain semiconductor region, an SiC base semiconductor region coupled to the SiC drift semiconductor region, an SiC source semiconductor region coupled to the SiC base semiconductor region, a source electrode coupled to the SiC source semiconductor region, a drain electrode coupled to the SiC drain semiconductor region, a gate electrode, wherein voltage of the gate electrode with respect to the SiC base semiconductor region is less than or equal to about 12 V and thickness of the dielectric material is such that the electric field in the dielectric material is about 4 MV/cm when said gate voltage is about 12 V.

A Metal Oxide Semiconductor (MOS) transistor cell design has multiple trench recesses embedding trench gate electrodes longitudinally extending in a third dimension, with interconnected first base layer, source regions, and a second base layer covering portions of the regions between adjacent trench recesses and longitudinally extending in the same third dimension. When a control voltage greater than a threshold value is applied on the trench gate electrodes, no vertical MOS channels are formable on the trench walls because each of trench recesses abuts at least one source regions and a connected highly doped second base layer. Instead, the charge carriers flow from a singular point within the source region, into a radial MOS channel formed only on the lateral walls of those trench regions abutting the first base layer, but not the higher doped second base layer.

A MOSFET device includes a semiconductor substrate, serving as a drain region, and an epitaxial region disposed on an upper surface of the substrate. The MOSFET device includes multiple body regions formed in the epitaxial region, and multiple source regions. The body regions are disposed near an upper surface of the epitaxial region and spaced laterally from one another, and each of the source regions is disposed in a corresponding one of the body regions near an upper surface of the body region. The MOSFET device includes a gate structure having multiple planar gates and a trench gate. Each of the planar gates is disposed on the upper surface of the epitaxial region overlapping a corresponding body region. The trench gate is formed partially through the epitaxial region and between the body regions, an upper surface of the trench gate being recessed below the upper surface of the epitaxial region.