A nitride semiconductor device includes a substrate, a first electron transport layer above the substrate, a first electron supply layer above the first electron transport layer, a first nitride semiconductor layer above the first electron supply layer, a first opening passing through the first nitride semiconductor layer and the first electron supply layer and reaching the first electron transport layer, a second electron transport layer disposed above the first nitride semiconductor layer and along the inner surface of the first opening, a second electron supply layer disposed above the second electron transport layer and covering the first opening, a gate electrode disposed above the second electron supply layer and covering the first opening, a source electrode connected to the first nitride semiconductor layer and the second electron transport layer, and a drain electrode.

A nitride semiconductor device includes a substrate, a first electron transport layer above the substrate, a first electron supply layer above the first electron transport layer, a first nitride semiconductor layer above the first electron supply layer, a first opening passing through the first nitride semiconductor layer and the first electron supply layer and reaching the first electron transport layer, a second electron transport layer disposed above the first nitride semiconductor layer and along the inner surface of the first opening, a second electron supply layer disposed above the second electron transport layer and covering the first opening, a gate electrode disposed above the second electron supply layer and covering the first opening, a source electrode connected to the first nitride semiconductor layer and the second electron transport layer, and a drain electrode.

A transistor device and a method for producing thereof are disclosed. The transistor device includes: a SiC semiconductor body that includes a first semiconductor layer; a plurality of trenches each extending from a first surface of the first semiconductor layer into the first semiconductor layer; and a plurality of transistor cells each coupled to a source node. The first semiconductor layer includes a plurality of mesa regions each formed between two neighboring ones of the trenches, in each of the mesa regions, at least one of the plurality of transistor cells is at least partially integrated, each of the transistor cells is connected to the source node via a respective source contact, and each of the source contacts is arranged in a respective one of the trenches and is spaced apart from a bottom of the respective trench.

A semiconductor device includes a junction field effect transistor (JFET) including a source electrode, a drain electrode, and a gate electrode, and a metal oxide semiconductor field effect transistor (MOSFET) including a source electrode, a drain electrode, and a gate electrode. The JFET and the MOSFET are cascode-connected such that the source electrode of the JFET and the drain electrode of the MOSFET are electrically connected. A gate voltage dependency of the JFET or a capacitance ratio of a mirror capacitance of the MOSFET to an input capacitance of the MOSFET is adjusted in a predetermined range.

A semiconductor device includes a MOSFET including a drift layer, a channel layer, a trench gate structure, a source layer, a drain layer, a source electrode, and a drain electrode. The trench gate structure includes a trench penetrating the channel layer and protruding into the drift layer, a gate insulating film disposed on a wall surface of the trench, and a gate electrode disposed on the gate insulating film. A portion of the trench protruding into the drift layer is entirely covered with a well layer, and the well layer is connected to the channel layer.

A 3D semiconductor device including: a first level including a single crystal silicon layer and a plurality of first transistors, the plurality of first transistors each including a single crystal channel; a first metal layer overlaying the plurality of first transistors; a second metal layer overlaying the first metal layer; a third metal layer overlaying the second metal layer; a second level is disposed above the third metal layer, where the second level includes a plurality of second transistors; a fourth metal layer disposed above the second level; and a connective path between the fourth metal layer and either the third metal layer or the second metal layer, where the connective path includes a via disposed through the second level, where the via has a diameter of less than 800 nm and greater than 5 nm, and where at least one of the plurality of second transistors includes a metal gate.

A 3D semiconductor device including: a first level including a single crystal silicon layer and a plurality of first transistors, the plurality of first transistors each including a single crystal channel; a first metal layer overlaying the plurality of first transistors; a second metal layer overlaying the first metal layer; a third metal layer overlaying the second metal layer; a second level is disposed above the third metal layer, where the second level includes a plurality of second transistors; a fourth metal layer disposed above the second level; and a connective path between the fourth metal layer and either the third metal layer or the second metal layer, where the connective path includes a via disposed through the second level, where the via has a diameter of less than 800 nm and greater than 5 nm, and where at least one of the plurality of second transistors includes a metal gate.

A nitride semiconductor device includes a substrate; a nitride semiconductor layered structure disposed on the substrate and having a channel region; a first electrode and a second electrode both disposed on the nitride semiconductor layered structure; a first p-type nitride semiconductor layer disposed between the first electrode and the second electrode; and a first gate electrode disposed on the first p-type nitride semiconductor layer. The nitride semiconductor layered structure includes a first recess. The first p-type nitride semiconductor layer is at least partially disposed inside the first recess, and is separated from a side surface of the first recess.

A semiconductor device includes a JFET and a MOSFET cascode-connected to each other such that a source electrode of the JFET is connected to a drain electrode of the MOSFET. The JFET is configured such that a breakdown voltage between a gate layer and a body layer is set lower than a breakdown voltage of the MOSFET.

A semiconductor device includes a JFET and a MOSFET cascode-connected to each other such that a source electrode of the JFET is connected to a drain electrode of the MOSFET. The JFET is configured such that a breakdown voltage between a gate layer and a body layer is set lower than a breakdown voltage of the MOSFET.