A bidirectional switch element includes: a substrate; an Al.sub.zGa.sub.1-zN layer; an Al.sub.bGa.sub.1-bN layer; a first source electrode; a first gate electrode; a second gate electrode; a second source electrode; a p-type Al.sub.x1Ga.sub.1-x1N layer; a p-type Al.sub.x2Ga.sub.1-x2N layer; an Al.sub.yGa.sub.1-yN layer; and an Al.sub.wGa.sub.1-wN layer. The Al.sub.zGa.sub.1-zN layer is formed over the substrate. The Al.sub.bGa.sub.1-bN layer is formed on the Al.sub.zGa.sub.1-zN layer. The Al.sub.yGa.sub.1-yN layer is interposed between the substrate and the Al.sub.zGa.sub.1-zN layer. The Al.sub.wGa.sub.1-wN layer is interposed between the substrate and the Al.sub.yGa.sub.1-yN layer and has a higher C concentration than the Al.sub.yGa.sub.1-yN layer.

A method for manufacturing a vertical JFET includes providing a III-nitride substrate having a first conductivity type and forming a first III-nitride layer coupled to the III-nitride substrate. The first III-nitride layer is characterized by a first dopant concentration and the first conductivity type. The method also includes forming a plurality of trenches within the first III-nitride layer and epitaxially regrowing a second III-nitride structure in the trenches. The second III-nitride structure is characterized by a second conductivity type. The method further includes forming a plurality of III-nitride fins, each coupled to the first III-nitride layer, wherein the plurality of III-nitride fins are separated by one of a plurality of recess regions, and epitaxially regrowing a III-nitride gate layer in the recess regions. The III-nitride gate layer is coupled to the second III-nitride structure and the III-nitride gate layer is characterized by the second conductivity type.

The present invention relates to a Semiconductor device including a first electrode, a second electrode and at least one semiconductor material or layer between the first and second electrode. The semiconductor device further includes at least one field plate structure for increasing a breakdown voltage of the semiconductor device. The at least one field plate structure comprises at least two recesses in the at least one semiconductor material or layer, the at least two recesses defining a semiconductor region therebetween, and a third electrode contacting or provided on the semiconductor region.

A silicon carbide substrate has a trench extending from a main surface of the silicon carbide substrate into the silicon carbide substrate. The trench has a trench width at a trench bottom. A shielding region is formed in the silicon carbide substrate. The shielding region extends along the trench bottom. In at least one doping plane extending approximately parallel to the trench bottom, a dopant concentration in the shielding region over a lateral first width deviates by not more than 10% from a maximum value of the dopant concentration. The first width is less than the trench width and is at least 30% of the trench width.

A vertical junction field effect transistor (JFET) includes a substrate, an active region having a plurality of semiconductor fins, a source metal layer on an upper surface of the fins, a source metal pad layer coupled to the semiconductor fins through the source metal layer, a gate region surrounding the semiconductor fins, and a body diode surrounding the gate region.

Germanium-based sensors are disclosed herein. An exemplary germanium-based sensor includes a germanium photodiode and a junction field effect transistor (JFET) formed from a germanium layer disposed in a silicon substrate, in some embodiments, or on a silicon substrate, in some embodiments. A doped silicon layer, which can be formed by in-situ doping epitaxially grown silicon, is disposed between the germanium layer and the silicon substrate. In embodiments where the germanium layer is on the silicon substrate, the doped silicon layer is disposed between the germanium layer and an oxide layer. The JFET has a doped polysilicon gate, and in some embodiments, a gate diffusion region is disposed in the germanium layer under the doped polysilicon gate. In some embodiments, a pinned photodiode passivation layer is disposed in the germanium layer. In some embodiments, a pair of doped regions in the germanium layer is configured as an e-lens of the germanium-based sensor.

Germanium-based sensors are disclosed herein. An exemplary germanium-based sensor includes a germanium photodiode and a junction field effect transistor (JFET) formed from a germanium layer disposed in a silicon substrate, in some embodiments, or on a silicon substrate, in some embodiments. A doped silicon layer, which can be formed by in-situ doping epitaxially grown silicon, is disposed between the germanium layer and the silicon substrate. In embodiments where the germanium layer is on the silicon substrate, the doped silicon layer is disposed between the germanium layer and an oxide layer. The JFET has a doped polysilicon gate, and in some embodiments, a gate diffusion region is disposed in the germanium layer under the doped polysilicon gate. In some embodiments, a pinned photodiode passivation layer is disposed in the germanium layer. In some embodiments, a pair of doped regions in the germanium layer is configured as an e-lens of the germanium-based sensor.

A 3D semiconductor device including: a first level including a single crystal silicon layer and a 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, where the second level overlays the first level and includes a plurality of second transistors; a fourth metal layer overlaying 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 and has a diameter of less than 500 nm and greater than 5 nm, where the third metal layer is connected to provide a power or ground signal to at least one of the second transistors.

A 3D semiconductor device including: a first level including a single crystal silicon layer and a 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, where the second level overlays the first level and includes a plurality of second transistors; a fourth metal layer overlaying 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 and has a diameter of less than 500 nm and greater than 5 nm, where the third metal layer is connected to provide a power or ground signal to at least one of the second transistors.

A semiconductor device including: a first silicon layer including a first single crystal silicon and a plurality of first transistors; a first metal layer disposed over the first silicon layer; a second metal layer disposed over the first metal layer; a third metal layer disposed over the second metal layer; a second level including a plurality of second transistors, the second level disposed over the third metal layer; a fourth metal layer disposed over the second level; a fifth metal layer disposed over the fourth metal layer, where the fourth metal layer is aligned to first metal layer with a less than 40 nm alignment error; and a via disposed through the second level, where each of the second transistors includes a metal gate, and where a typical thickness of the second metal layer is greater than a typical thickness of the third metal layer by at least 50%.