The disclosure belongs to the technical field of semiconductor power devices, specifically relates to a semi-floating-gate power device, and comprises the gallium nitride high-electron-mobility transistor, the diode and the capacitor; the anode of the diode is connected with the gate of the gallium nitride high-electron-mobility transistor and the cathode of the diode is connected with the source or the channel area of the gallium nitride high-electron-mobility transistor; one end of the capacitor is connected with the gate of the gallium nitride high-electron-mobility transistor and the other end of the capacitor is connected with the external voltage signal. The semi-floating-gate power device has a simple structure, is easy to manufacture, adapts to high-voltage and high-speed operation and has very high reliability, can increase the threshold voltage of the gallium nitride high-electron-mobility transistor in the working state, so that the transistor can serve as the power switch tube better.

Semiconductor devices comprising a getter material are described. The getter material can be located in or over the active region of the device and/or in or over a termination region of the device. The getter material can be a conductive or an insulating material. The getter material can be present as a continuous or discontinuous film. The device can be a SiC semiconductor device such as a SiC vertical MOSFET. Methods of making the devices are also described. Semiconductor devices and methods of making the same comprising source ohmic contacts formed using a self-aligned process are also described. The source ohmic contacts can comprise titanium silicide and/or titanium silicide carbide and can act as a getter material.

A method of producing a silicon carbide epitaxial substrate includes steps of: preparing a silicon carbide substrate; and forming a silicon carbide layer on the silicon carbide substrate. In this production method, in the step of forming the silicon carbide layer, a step of growing an epitaxial layer and a step of polishing a surface of the epitaxial layer are repeated twice or more.

[Object] To provide a semiconductor device capable of improving a discharge starting voltage when measuring electric characteristics, and widening a pad area of a surface electrode or increasing the number of semiconductor devices (number of chips) to be obtained from one wafer, and a method for manufacturing the same.

[Solution Means] A semiconductor device 1 includes an n-type SiC layer 2 having a first surface 2A, a second surface 2B, and end faces 2C, a p-type voltage relaxing layer 7 formed in the SiC layer 2 so as to be exposed to the end portion of the first surface 2A of the SiC layer 2, an insulating layer 8 formed on the SiC layer 2 so as to cover the voltage relaxing layer 7, and an anode electrode 9 that is connected to the first surface 2A of the SiC layer 2 through the insulating layer 8 and has a pad area 95 selectively exposed.

A semiconductor device is provided that is excellent in semiconductor properties and Schottky characteristics. A semiconductor device includes: a semiconductor layer containing a crystalline oxide semiconductor with a corundum structure as a major component; and a Schottky electrode on the semiconductor layer, wherein the Schottky electrode is formed by containing a metal of Groups 4-9 of the periodic table, thereby manufacturing a semiconductor device excellent in semiconductor properties and Schottky characteristics without impairing the semiconductor properties to use the semiconductor device thus obtained for a power device and the like.

A semiconductor device includes an n.sup.+ type silicon carbide substrate, and in the substrate an active region where primary current flows and an edge termination area surrounding the active region. The semiconductor device has a first p-type region and a second p-type region in the edge termination area, and the first p-type region includes therein a plurality of third p-type regions, and the second p-type region includes therein a plurality of fourth p-type regions. The widths between the respective plurality of third p-type regions and the widths between the respective plurality of fourth p-type regions become greater further away from the active region.

A semiconductor device include a substrate, a first well region formed in the substrate, a first isolation structure formed in the first well region, a Schottky barrier structure formed on the first well region, and a plurality of assist structures formed on the first well region. The substrate includes a first conductivity type, the first well region includes a second conductivity type, and the first conductivity type and the second conductivity type are complementary to each other. The assist structures physically contact the first well region.

A target made of a metal material is sputtered to form a metal film on a silicon carbide wafer. At this time, the metal film is formed under a condition that an incident energy of incidence, on the silicon carbide wafer, of the metal material sputtered from the target and a sputtering gas flowed in through a gas inlet port is lower than a binding energy of silicon carbide, and more specifically lower than 4.8 eV. For example, the metal film is formed while a high-frequency voltage applied between a cathode and an anode is set to be equal to or higher than 20V and equal to or lower than 300V.

A semiconductor device includes a first conductivity type semiconductor layer that includes a wide bandgap semiconductor and a surface. A trench, including a side wall and a bottom wall, is formed in the semiconductor layer surface, and a Schottky electrode is connected to the surface. Opposite edge portions of the bottom wall of the trench each include a radius of curvature, R, satisfying the expression 0.01 L<R<10 L, where L represents the straight-line distance in a width direction of the trench between the opposite edge portions.

The present invention discloses an electronic device using a group III nitride substrate fabricated via the ammonothermal method. By utilizing the high-electron concentration of ammonothermally grown substrates having the dislocation density less than 10.sup.5 cm.sup.2, combined with a high-purity active layer of Ga.sub.1-x-yAl.sub.xIn.sub.yN (0x1, 0y1) grown by a vapor phase method, the device can attain high level of breakdown voltage as well as low on-resistance. To realize a good matching between the ammonothermally grown substrate and the high-purity active layer, a transition layer is optionally introduced. The active layer is thicker than a depletion region created by a device structure in the active layer.