According to one embodiment, a semiconductor device includes a first electrode, first, second, and third semiconductor regions, an insulating portion, a conductive portion, a gate electrode, and a second electrode. The first semiconductor region is provided on the first electrode and electrically connected to the first electrode. The second semiconductor region is provided on the first semiconductor region. The third semiconductor region is provided on the second semiconductor region. The insulating portion are arranged with a portion of the first semiconductor region, and the second and third semiconductor regions. The conductive portion is provided inside the insulating portion and arranged with the first semiconductor region. The gate electrode is provided inside the insulating portion and arranged with the second semiconductor region. The second electrode is provided on the third semiconductor region and electrically connected to the third semiconductor region.

A method and vertical FET device fabricated in GaN or other suitable material. The device has a selective area implant region comprising an activated impurity configured from a bottom portion of a recessed regions, and substantially free from ion implant damage by using an annealing process. A gate region is configured from the selective area implant region, and each of the recessed regions is characterized by a depth configured to physically separate an n+ type source region and the p-type gate region such that a low reverse leakage gate-source p-n junction is achieved. An extended drain region is configured from a portion of an n− type GaN region underlying the recessed regions. An n+ GaN region is formed by epitaxial growth directly overlying the backside region of the GaN substrate and a backside drain contact region configured from the n+ type GaN region overlying the backside region.

A semiconductor device includes a guard structure located laterally between first and second active areas of a semiconductor substrate. The guard structure includes a first doping region at a front side surface of the substrate and a wiring structure electrically connecting the first doping region to a highly doped portion of a common doping region. The common doping region extends from a backside surface of the substrate to at least a part of the front side surface in contact with the wiring structure. An edge termination doping region laterally surrounds the first and second active areas. The edge termination doping region and the first doping region have a first conductivity type, and the common doping region has a second conductivity type. A resistive connection between the edge termination doping region and the first doping region is present at least during reverse operating conditions of the semiconductor device.

A power semiconductor device has a semiconductor body configured to conduct a load current in parallel to an extension direction between first and second load terminals of the power semiconductor device. The semiconductor body includes a doped contact region electrically connected to the second load terminal, a doped drift region having a dopant concentration that is smaller than a dopant concentration of the contact region, and an epitaxially grown doped transition region separated from the second load terminal by the contact region and that couples the contact region to the drift region. An upper subregion of the transition region is in contact with the drift region, and a lower subregion of the transition region is in contact with the contact region. The transition region has a dopant concentration of at least 0.5*10.sup.15 cm.sup.−3 for at least 5% of the total extension of the transition region in the extension direction.

When a nitride semiconductor layer into which impurity ions have been implanted is subjected to annealing after a protective film is provided on the nitride semiconductor layer, vacancy defects may be disadvantageously prevented from escaping outside through the surface of the nitride semiconductor layer and disappearing. A manufacturing method of a semiconductor device including a nitride semiconductor layer is provided. The manufacturing method includes implanting impurities into the nitride semiconductor layer, performing a first annealing on the nitride semiconductor layer at a first temperature within an atmosphere of a nitrogen atom containing gas without providing a protective film on the nitride semiconductor layer, forming the protective film on the nitride semiconductor layer after the first annealing, and after the protective film is formed, performing a second annealing on the nitride semiconductor layer at a second temperature that is higher than the first temperature.

A method of fabricating a semiconductor device includes forming a first semiconductor region at a front surface of a substrate, the first semiconductor region including an active element that regulates current flowing in a thickness direction of the substrate; grinding a rear surface of the substrate; after the grinding, performing a first etching that etches the rear surface of the substrate with a chemical solution including phosphorus; after the first etching, performing a second etching that etches the rear surface with an etching method with a lower etching rate than the first etching; and after the second etching, forming a second semiconductor region through which the current is to flow, by implanting impurities from the rear surface of the substrate.

A SiC MOSFET device having low specific on resistance is described. The device has N+, P-well and JFET regions extended in one direction (Y-direction) and P+ and source contacts extended in an orthogonal direction (X-direction). The polysilicon gate of the device covers the JFET region and is terminated over the P-well region to minimize electric field at the polysilicon gate edge. In use, current flows vertically from the drain contact at the bottom of the structure into the JFET region and then laterally in the X direction through the accumulation region and through the MOSFET channels into the adjacent N+ region. The current flowing out of the channel then flows along the N+ region in the Y-direction and is collected by the source contacts and the final metal. Methods of making the device are also described.

The present invention provides a DMOS device and a manufacturing method thereof. The DMOS device includes: a substrate, an epitaxial layer, a high voltage well, a body region, a gate, a source, a drain, a drift buried region and a buried region. A first PN junction is formed between the high voltage well and an upper surface of the substrate. From a cross-section view, along the channel direction, a second PN junction is formed between the drift buried region and the buried region or formed between the high voltage well and the buried region. Along the channel direction, the first PN junction and the second PN junction have respective depths. The depth is defined as a distance extending from the upper face of the epitaxial layer downward along a vertical direction. The depth of the second PN junction is shallower than the depth of the first PN junction.

A method for increasing a forward biased safe operating area of a device includes forming a gate; and forming a segmented source close to the gate, wherein the segmented source includes first segments associated with a first threshold voltage and second segments associated with a second threshold voltage different from the first threshold voltage, wherein at least one device characteristic associated with the first segments is different from the same device characteristic associated with the second segments.

According to one embodiment, a semiconductor device includes first and second electrodes, first to fifth semiconductor regions, and a gate electrode. The first semiconductor region is provided on the first electrode, and electrically connected to the first electrode. The second semiconductor region is provided on a part of the first semiconductor region. The third semiconductor region is provided on another part of the first semiconductor region. The third semiconductor region includes first and second regions. The fourth semiconductor region is provided on the second semiconductor region. The fifth semiconductor region is provided on a part of the fourth semiconductor region. The gate electrode faces the fourth semiconductor region with a gate insulating layer interposed between the gate electrode and the fourth semiconductor region. The second electrode is provided on the fourth and fifth semiconductor regions. The second electrode is electrically connected to the fourth and fifth semiconductor regions.