A semiconductor structure is provided. The semiconductor structure includes a substrate, a first doped region formed in the substrate, a second doped region formed in the substrate and surrounding the first doped region, and a plurality of strip third doped regions formed in the substrate and located underneath the first doped region and the second doped region. In addition, the first doped region has a doping type which is the opposite of that of the second doped region. The strip third doped region has a doping type which is the same as that of the second doped region.

A Field Effect Transistor (FET) may include a semiconductor substrate having a first conductivity type, a semiconductor layer of the first conductivity type formed over the substrate, and a pair of doped bodies of a second conductivity type opposite the first conductivity type formed in the semiconductor layer. A trench filled with a trench dielectric is formed within a region between the doped bodies. The FET may be a Vertical Metal-Oxide-Semiconductor FET (VMOSFET) including a gate dielectric disposed over the region between the doped bodies and the trench, and a gate electrode disposed over the gate dielectric, wherein the trench operates to prevent breakdown of the gate dielectric, or the FET may be a Junction FET. The FET may be designed to operate at radio frequencies or under heavy-ion bombardment. The semiconductor substrate and the semiconductor layer may comprise a wide band-gap semiconductor such as silicon carbide.

A semiconductor has a layer of a first conductivity type with a main surface, a trench separation structure which includes a separation trench formed in the main surface, a separation insulating film that covers a wall surface of the separation trench and a separation electrode that is embedded in the separation trench across the separation insulating film, the trench separation structure demarcating an outer region and an active region in the main surface, a floating region of a second conductivity type which is formed in an electrically floating state at a surface layer portion of the main surface along the trench separation structure in the outer region, and a Schottky electrode which is electrically connected to the separation electrode such as to retain the floating region in the electrically floating state in the outer region and which forms a Schottky junction with the main surface in the active region.

A Ga.sub.2O.sub.3-based semiconductor device includes a Ga.sub.2O.sub.3-based crystal layer including a donor, and an N-doped region formed in at least a part of the Ga.sub.2O.sub.3-based crystal layer.

A semiconductor device includes a semiconductor part, a first electrode at a back surface of the semiconductor part; a second electrode at a front surface of the semiconductor part; third and fourth electrodes provided between the semiconductor part and the second electrode. The third and fourth electrodes are arranged in a first direction along the front surface of the semiconductor part. The third electrode is electrically insulated from the semiconductor part by a first insulating film. The third electrode is electrically insulated from the second electrode by a second insulating film. The fourth electrode is electrically insulated from the semiconductor part by a third insulating film. The fourth electrode is electrically isolated from the third electrode. the third and fourth electrodes extend into the semiconductor part. The fourth electrode includes a material having a larger thermal conductivity than a thermal conductivity of a material of the third electrode.

According to an embodiment of the invention, a semiconductor device includes a base body that includes silicon carbide, a first semiconductor member that includes silicon carbide and is of a first conductivity type, and a second semiconductor member that includes silicon carbide and is of a second conductivity type. A first direction from the base body toward the first semiconductor member is along a [0001] direction of the base body. The second semiconductor member includes a first region, a second region, and a third region. The first semiconductor member includes a fourth region. A second direction from the first region toward the second region is along a [1-100] direction of the base body. The fourth region is between the first region and the second region in the second direction. A third direction from the fourth region toward the third region is along a [11-20] direction of the base body.

A semiconductor device includes a semiconductor part; first and second electrodes respectively on back and front surfaces of the semiconductor part; a control electrode provided inside a trench of the semiconductor part; a third electrode provided inside the trench; a diode element provided at the front surface of the semiconductor part; a resistance element provided on the front surface of the semiconductor part via an insulating film, the diode element being electrically connected to the second electrode; a first interconnect electrically connecting the diode element and the resistance element, the first interconnect being electrically connected to the third electrode; and a second interconnect electrically connecting the resistance element and the semiconductor part. The resistance element is connected in series to the diode element. The diode element is provided to have a rectifying property reverse to a current direction flowing from the resistance element to the second electrode.

Provided are a semi-conductor structure and a manufacturing method thereof. The semi-conductor structure includes: a substrate, a heterojunction, a P-type ion doped layer and a gate insulation layer disposed from bottom to top, wherein the heterojunction includes a source region, a drain region and a gate region; the P-type ion doped layer in the gate region includes an activated region and non-activated regions, P-type doping ions in the activated region are activated, and P-type doping ions in the non-activated regions are passivated; the non-activated regions include at least two regions which are spaced apart in a direction perpendicular to a connection line of the source region and the drain region; the gate insulation layer is located on the non-activated region to expose the activated region.

A high electron mobility transistor includes a channel layer; a barrier layer on the channel layer and having an energy bandgap greater than an energy bandgap of the channel layer; a gate structure on the barrier layer; a source electrode and a drain electrode spaced apart from each other on the barrier layer with the gate structure therebetween; a field plate electrically connected to the source electrode and extending above the gate structure; and a field dispersion layer in contact with the barrier layer and the drain electrode. The field dispersion layer may extend toward the gate structure.

A high electron mobility transistor (HEMT) includes a carrier transit layer, a carrier supply layer, a main gate, a control gate, a source electrode and a drain electrode. The carrier transit layer is on a substrate. The carrier supply layer is on the carrier transit layer. The main gate and the control gate are on the carrier supply layer. A fluoride ion doped region is formed right below the main gate in the carrier supply layer. The source electrode and the drain electrode are at two opposite sides of the main gate and the control gate, wherein the source electrode is electrically connected to the control gate by a metal interconnect. The present invention also provides a method of forming a high electron mobility transistor (HEMT).