A semiconductor device includes an element portion and a gate pad portion on the same wide gap semiconductor substrate. The element portion includes a first trench structure having a plurality of first protective trenches and first buried layers formed deeper than gate trenches. The gate pad portion includes a second trench structure having a plurality of second protective trenches and second buried layers. The second trench structure is either one of a structure where the second trench structure includes: a p-type second semiconductor region and a second buried layer made of a conductor or a structure where the second trench structure includes a second buried layer formed of a metal layer which forms a Schottky contact. The second buried layer is electrically connected with the source electrode layer.

A semiconductor apparatus includes: a gate electrode in a trench and facing a p type base region with a gate insulating film interposed therebetween on a portion of a side wall; a shield electrode in the trench and between the gate electrode and a bottom of the trench; an electric insulating region in the trench, the electric insulating region extending between the gate electrode and the shield electrode, and further extending along the side wall and the bottom of the trench to separate the shield electrode from the side wall and the bottom; a source electrode electrically connected to an n.sup.+ type source region and the shield electrode. The shield electrode has high resistance regions at positions where the high resistance regions face the side walls of the trench, and a low resistance region at a position where the low resistance region is sandwiched between the high resistance regions.

Provided is a semiconductor apparatus includes: a gate electrode disposed inside a trench and opposedly facing a p type base region with a gate insulating film interposed therebetween on a portion of a side wall; a shield electrode disposed inside the trench and positioned between the gate electrode and a bottom of the trench; an electric insulating region disposed inside the trench, the electric insulating region expanding between the gate electrode and the shield electrode, and further expanding along the side wall and the bottom of the trench so as to separate the shield electrode from the side wall and the bottom; a source electrode electrically connected to an n.sup.+ type source region and the shield electrode, wherein the shield electrode has a high resistance region positioned on an n.sup.+ drain region side, and a low resistance region positioned on a gate electrode side.

Semiconductor devices includes a thin epitaxial layer (nanotube) formed on sidewalls of mesas formed in a semiconductor layer. In one embodiment, a semiconductor device includes a first semiconductor layer, a second semiconductor layer formed thereon and of the opposite conductivity type, and a first epitaxial layer formed on mesas of the second semiconductor layer. An electric field along a length of the first epitaxial layer is uniformly distributed.

A semiconductor device includes: an FET structure that is formed next to a looped trench on a semiconductor substrate and that has an n.sup.+ emitter region and an n.sup. drain region facing each other in the depth direction of the looped trench across a p-type base region; a p-type floating region formed on the side of the looped trench opposite to the FET structure; and an emitter connecting part that is electrically connected to the n.sup.+ emitter region and a trench gate provided in the same trench, the emitter connecting part and the trench gate being insulated from each other by the looped trench. The trench gate faces the FET structure, and the emitter connecting part faces the p-type floating region, across an insulating film.

In one embodiment, a power MOSFET cell includes an N+ silicon substrate having a drain electrode. An N-type drift layer is grown over the substrate. An N-type layer, having a higher dopant concentration than the drift region, is then formed along with a trench having sidewalls. A P-well is formed in the N-type layer, and an N+ source region is formed in the P-well. A gate is formed over the P-well's lateral channel and has a vertical extension into the trench. A positive gate voltage inverts the lateral channel and increases the vertical conduction along the sidewalls to reduce on-resistance. A vertical shield field plate is also located next to the sidewalls and may be connected to the gate. The field plate laterally depletes the N-type layer when the device is off to increase the breakdown voltage. A buried layer and sinker enable the use of a topside drain electrode.

An electronic device can include a bidirectional HEMT. In an aspect, the electronic device can include a pair of switch gate and blocking gate electrodes, wherein the switch gate electrodes are not electrically connected to the blocking gate electrodes, and the first blocking, first switch, second blocking, and second switch gate electrodes are on the same die. In another aspect, the electronic device can include shielding structures having different numbers of laterally extending portions. In a further aspect, the electronic device can include a gate electrode and a shielding structure, wherein a portion of the shielding structure defines an opening overlying the gate electrode.

A semiconductor device according to an embodiment includes a first nitride semiconductor layer; a source electrode provided on the first nitride semiconductor layer; a drain electrode provided on the first nitride semiconductor layer; a gate electrode provided between the source electrode and the drain electrode; a first film provided between the source electrode and the gate electrode and between the gate electrode and the drain electrode; and a second film provided on the first film. The first film is provided on the first nitride semiconductor layer. The first film has a lower hydrogen diffusion coefficient than a hydrogen diffusion coefficient of a silicon oxide film.

A semiconductor device with a current terminal region located in a device active area of a substrate of the device. A guard region is located in a termination area of the device. A plurality of floating field plates are located in the termination area and are ohmically coupled to the guard region. The floating field plates and guard region act in some embodiments to smooth the electrical field distribution along the termination area.

Apparatus and associated methods relate to an edge-termination structure surrounding a high-voltage MOSFET for reducing a peak lateral electric field. The edge-termination structure includes a sequence of annular trenches and semiconductor pillars circumscribing the high-voltage MOSFET. Each of the annular trenches is laterally separated from the other annular trenches by one of the semiconductor pillars. Each of the annular trenches has dielectric sidewalls and a dielectric bottom electrically isolating a conductive core within each of the annular trenches from a drain-biased region of the semiconductor pillar outside of and adjacent to the annular trench. The conductive core of the innermost trench is biased, while the conductive cores of one or more outer trenches are floating. In some embodiments, a surface of an inner semiconductor pillar is biased as well. The peak lateral electric field can advantageously be reduced by physical arrangement of trenches and electrical biasing sequence.