Method for producing a JFET transistor, comprising: a) producing, on a first substrate, a stack comprising a first layer comprising a first semiconductor doped according to a first conductivity type and a second layer comprising a second semiconductor doped according to a second conductivity type, the first layer being disposed between the first substrate and the second substrate, then b) securing the stack against a second substrate such that the stack is disposed between the first substrate and the second substrate, then c) removing the first substrate, then d) etching the first layer such that a remaining portion of the first layer forms a front gate of the first JFET transistor, then e) etching the second layer such that a remaining portion of the second layer is disposed below the front gate of the first JFET transistor and forms the channel, the source and the drain of the JFET transistor.

A method of manufacturing a substrate includes forming a support structure by providing a polycrystalline ceramic core, encapsulating the polycrystalline ceramic core in a first adhesion shell, encapsulating the first adhesion shell in a conductive shell, encapsulating the conductive shell in a second adhesion shell, and encapsulating the second adhesion shell in a barrier shell. The method also includes joining a bonding layer to the support structure, joining a substantially single crystalline silicon layer to the bonding layer, forming an epitaxial silicon layer by epitaxial growth on the substantially single crystalline silicon layer, and forming one or more epitaxial layers by epitaxial growth on the epitaxial silicon layer.

A semiconductor device may include a substrate and a hyper-abrupt junction region carried by the substrate. The hyper-abrupt junction region may include a first semiconductor layer having a first conductivity type, a first superlattice layer on the first semiconductor layer, a second semiconductor layer on the first superlattice layer and having a second conductivity type different than the first conductivity type, and a second superlattice layer on the second semiconductor layer. The semiconductor device may further include a first contact coupled to the hyper-abrupt junction regions and a second contact coupled to the substrate to define a varactor. The first and second superlattices may each include stacked groups of layers, with each group of layers including stacked base semiconductor monolayers defining a base semiconductor portion, and at least one non-semiconductor monolayer constrained within a crystal lattice of adjacent base semiconductor portions.

A method is presented for forming a semiconductor device. The method may include forming a first gate structure on a first portion of a semiconductor material located on a surface of an insulating substrate, the first gate structure including a first sacrificial layer and a second sacrificial layer and forming a second gate structure on a second portion of the semiconductor material located on the surface of the insulating substrate, the second gate structure including a third sacrificial layer. The method further includes etching the first and second dielectric sacrificial layers to create a first contact region within the first gate structure and etching the third dielectric sacrificial layer to create a second contact region within the second gate structure. The method further includes forming silicide in at least the first and second contact regions of the first and second gate structures, respectively.

A shielded Schottky heterojunction power transistor is made from a Silicon-Carbide (SiC) wafer with SiC epitaxial layers including a N+ source and a Silicon N-epitaxial layer under the gate with higher channel mobility than SiC. The bulk of the wafer is a N+ SiC drain contacted by backside metal. A trench is formed between heterojunction transistors. Metal contacting the N+ source is extended into the trench to form a Schottky diode with the N-SiC substrate. P+ taps on the sides of the trench connect the metal to a P-SiC body diode under the heterojunction gate, and also prevent the Schottky metal from directly contacting the P body diode. Buried P pillars with P+ pillar caps are formed under the trench Schottky diode and under the heterojunction transistors. The P pillars provide shielding by balancing charge with the N substrate, acting as dielectrics to reduce the E-field above the pillars.

Current conducting devices and methods for their formation are disclosed. Described are vertical current devices that include a substrate, an n-type material layer, a plurality of p-type gates, and a source. The n-type material layer disposed on the substrate and includes a current channel. A plurality of p-type gates are disposed on opposite sides of the current channel. A source is disposed on a distal side of the current channel with respect to the substrate. The n-type material layer comprises beta-gallium oxide.

A method of manufacturing a substrate includes forming a support structure by providing a polycrystalline ceramic core, encapsulating the polycrystalline ceramic core in a first adhesion shell, encapsulating the first adhesion shell in a conductive shell, encapsulating the conductive shell in a second adhesion shell, and encapsulating the second adhesion shell in a barrier shell. The method also includes joining a bonding layer to the support structure, joining a substantially single crystalline silicon layer to the bonding layer, forming an epitaxial silicon layer by epitaxial growth on the substantially single crystalline silicon layer, and forming one or more epitaxial III-V layers by epitaxial growth on the epitaxial silicon layer.

A field-effect transistor includes an n-type semiconductor layer that includes a Ga.sub.2O.sub.3-based single crystal and a plurality of trenches opening on one surface, a gate electrode buried in each of the plurality of trenches, a source electrode connected to a mesa-shaped region between adjacent trenches in the n-type semiconductor layer, and a drain electrode directly or indirectly connected to the n-type semiconductor layer on an opposite side to the source electrode.

A method is presented for forming a monolithically integrated semiconductor device. The method includes forming a first device including first hydrogenated silicon-based contacts formed on a first portion of a semiconductor material of an insulating substrate and forming a second device including second hydrogenated silicon-based contacts formed on a second portion of the semiconductor material of the insulating substrate. Source and drain contacts of the first device are formed before a gate contact of the first device and a gate contact of the second device is formed before the emitter and collector contacts of the second device. The first device can be a heterojunction field effect transistor (HJFET) and the second device can be a (heterojunction bipolar transistor) HBT. The HJFET and the HBT are integrated in a neuronal circuit and create negative differential resistance by forming a lambda diode.

A method of manufacturing a substrate includes forming a support structure by providing a polycrystalline ceramic core, encapsulating the polycrystalline ceramic core in a first adhesion shell, encapsulating the first adhesion shell in a conductive shell, encapsulating the conductive shell in a second adhesion shell, and encapsulating the second adhesion shell in a barrier shell. The method also includes joining a bonding layer to the support structure, joining a substantially single crystalline silicon layer to the bonding layer, forming an epitaxial silicon layer by epitaxial growth on the substantially single crystalline silicon layer, and forming one or more epitaxial III-V layers by epitaxial growth on the epitaxial silicon layer.