An integrated circuit (IC) includes a field-plated transistor including a substrate having a semiconductor surface layer, at least one body region in the semiconductor surface layer, and at least a first trench isolation region adjacent to the body region having at least a first tapered sidewall that has an average angle along its full length of 15 to 70 degrees. A gate is over the body region. A field plate is over the first tapered trench isolation region. A source is on one side of the field plate and a drain is on an opposite side of the field plate. The IC also includes circuitry for realizing at least one circuit function having a plurality of transistors which are configured together with the field-plated transistor that utilize second trench isolation regions for isolation that have an average angle of 75 and 90 degrees.

A semiconductor diode includes a wide bandgap semiconductor body having opposing first and second surfaces. The wide band gap semiconductor body includes a first pn junction diode having a first p-doped region adjoining the first surface and a first n-doped region adjoining both surfaces. The semiconductor diode further includes a semiconductor element including a second pn junction diode having a second p-doped region and second n-doped region, and a dielectric structure between the wide bandgap semiconductor body and semiconductor element. The dielectric structure electrically insulates the wide bandgap semiconductor body from the semiconductor element. The bandgap energy of the semiconductor element is smaller than that of the wide bandgap semiconductor body. A cathode contact is electrically connected to the first n-doped region at the second surface. The second n-doped region of the second pn junction diode is electrically coupled to the first n-doped region of the first pn junction diode.

Provided is a semiconductor element including at least, a semiconductor layer including a crystalline oxide semiconductor as a major component; an electrode layer laminated on the semiconductor layer; and a conductive substrate laminated on the electrode layer directly or with another layer in between, the conductive substrate containing at least a first metal selected from the metals in group 11 in the periodic table and a second metal different from the first metal in coefficient of liner thermal expansion.

A semiconductor device includes a semiconductor element configured to form an upper-lower arm circuit of a power conversion device. The semiconductor element includes a control electrode, a high-potential electrode and a low-potential electrode. A parasitic capacitance between the control electrode and the high-potential electrode changes according to a potential difference between the high-potential electrode and the low-potential electrode. A value of the parasitic capacitance at a time when the potential difference is equal to 80 percent of a breakdown voltage of the semiconductor element is defined as a first capacitance value. An arbitrary value of the parasitic capacitance at a time when the potential difference is in an inclusive range of 20 percent to 40 percent of the breakdown voltage is defined as a second capacitance value. The first capacitance value is larger than the second capacitance value.

A source layer is provided on a first p-type layer made of a nitride-based semiconductor, and includes a semiconductor region including electrons as carriers. A drain layer faces the source layer in a first direction on the first p-type layer with a gap being provided therebetween, and includes a semiconductor region including electrons as carriers. A channel structure is provided between the source layer and the drain layer on the first p-type layer, in which a channel region and a gate region are alternately disposed in a second direction perpendicular to the first direction. A channel layer included in the channel structure forms at least a part of the channel region, and is made of a nitride-based semiconductor. A gate layer included in the channel structure forms at least a part of the gate region, and electrically connects a gate electrode and the first p-type layer.

A SiC semiconductor device includes a substrate of a first conductivity type, a buffer layer of the first conductivity type on the substrate, a low-concentration layer on the buffer layer, a first deep layer and a JFET portion on the low-concentration layer, a current diffusion layer of the first conductivity type disposed on the JFET portion and having an impurity concentration higher than the low-concentration layer, a second deep layer of a second conductivity type disposed on the first deep layer, a base layer of the second conductivity type disposed on the current diffusion layer and the second deep layer, an impurity region of the first conductivity type disposed in a surface layer portion of the base layer, and a trench gate structure penetrating the impurity region and the base layer and reach the current diffusion layer. The JFET portion is formed with defect portions.

An integrated circuit includes a junction field-effect transistor formed in a semiconductor substrate. The junction field-effect transistor includes a drain region, a source region, a channel region, and a gate region. A first isolating region separates the drain region from both the gate region and the channel region. A first connection region connects the drain region to the channel region by passing underneath the first isolating region in the semiconductor substrate. A second isolating region separates the source region from both the gate region and the channel region. A second connection region connects the source region to the channel region by passing underneath the second isolating region in the semiconductor substrate.

A field-plate trench FET having a drain region, an epitaxial layer, a source region, a gate conductive layer formed in a trench, a field-plate dielectric layer formed on vertical sidewalls of the trench, a well region formed below the trench, a source contact and a gate contact. When the well region is in direct physical contact with the gate conductive layer, the field-plate trench FET can be used as a normally-on device working depletion mode, and when the well region is electrically isolated from the gate conductive layer by the field-plate layer, the field-plate trench FET can be used as a normally-off device working in an accumulation-depletion mode.

A semiconductor device includes a junction field effect transistor (JFET) on a silicon-on-insulator (SOI) substrate. The JFET includes a gate with a first gate segment contacting the channel on a first lateral side of the channel, and a second gate segment contacting the channel on a second, opposite, lateral side of the channel. The first gate segment and the second gate segment extend deeper in the semiconductor layer than the channel. The JFET further includes a drift region contacting the channel, and may include a buried layer having the same conductivity type as the channel, extending at least partway under the drift region.

An integrated circuit includes a junction field-effect transistor formed in a semiconductor substrate. The junction field-effect transistor includes a drain region, a source region, a channel region, and a gate region. A first isolating region separates the drain region from both the gate region and the channel region. A first connection region connects the drain region to the channel region by passing underneath the first isolating region in the semiconductor substrate. A second isolating region separates the source region from both the gate region and the channel region. A second connection region connects the source region to the channel region by passing underneath the second isolating region in the semiconductor substrate.