A method of fabricating a gate stack for a power transistor device includes thermally oxidizing a surface of a Group IIIA-N layer on a substrate to form a first dielectric layer of an oxide material that is >5A thick. A second dielectric layer being silicon nitride or silicon oxynitride is deposited on the first dielectric layer. A metal gate electrode is formed on the second dielectric layer.

A semiconductor device includes a substrate, a power device, a protection circuit, a dielectric layer, a drain pad, a source pad, and a gate pad. The power device and the protection circuit are disposed on the substrate. The power device includes a drain electrode, a source electrode, and a gate electrode. The protection circuit has a first terminal electrically connected with the source pad and a second terminal electrically connected with the gate pad. The dielectric layer is disposed on the power device and the protection circuit. The drain pad, the source pad, and the gate pad are disposed on the dielectric layer and respectively electrically connected with the drain electrode, the source electrode, and the gate electrode. At least part of the protection circuit is disposed under the source pad, the gate pad, or the drain pad.

Components can be damaged if they are exposed to excess voltages. A device is disclosed herein which can be placed in series with a component and a node that may be exposed to high voltages. If the voltage becomes too high, the device can autonomously switch into a relatively high impedance state, thereby protecting the other components.

A method of fabricating an epitaxial stack for Group IIIA-N transistors includes depositing at least one Group IIIA-N buffer layer on a substrate in a deposition chamber of a deposition system. At least one Group IIIA-N cap layer is then deposited on the first Group IIIA-N buffer layer. During a cool down from the deposition temperature for the cap layer deposition the gas mixture supplied to the deposition chamber includes NH.sub.3 and at least one other gas, wherein the gas mixture provide an ambient in the deposition chamber that is non-etching with respect to the cap layer so that at a surface of the cap layer there is (i) a room mean square (rms) roughness of <10 and (ii) a pit density for pits greater than (>) 2 nm deep less than (<) 10 pits per square m with an average pit diameter less than (<) 0.05 m.

In order to secure the performance of a SiC-based JFET having an impurity diffusion rate lower than silicon-based one, a gate depth is secured while precisely controlling a distance between gate regions, instead of forming gate regions by ion implantation into the side wall of a trench. This means that a channel region defined by a gate distance and a gate depth should have a high aspect ratio. Further, due to limitations of process, a gate region is formed within a source region. Formation of a highly doped PN junction between source and gate regions causes various problems such as inevitable increase in junction current. In addition, a markedly high energy ion implantation becomes necessary for the formation of a termination structure. In the invention, provided is a vertical channel type SiC power JFET having a floating gate region below and separated from a source region and between gate regions.

Junction field-effect transistors including inorganic channels and organic gate junctions are used in some applications for forming high resolution active matrix displays. Arrays of such junction field-effect transistors are electrically connected to thin film switching transistors and provide high drive currents for passive devices such as organic light emitting diodes.

A Dual-wavelength hybrid (DWH) device includes an n-type ohmic contact layer, cathode and anode terminal electrodes, first and second injector terminal electrodes, p-type and n-type modulation doped QW structures, and first through sixth ion implant regions. The first injector terminal electrode is formed on the third ion implant region that contacts the p-type modulation doped QW structure and the second injector terminal electrode is formed on the fourth ion implant region that contacts the n-type modulation doped QW structure. The DWH device operates in at least one of a vertical cavity mode and a whispering gallery mode. In the vertical cavity mode, the DWH device converts an in-plane optical mode signal to a vertical optical mode signal, whereas in the whispering gallery mode the DWH device converts a vertical optical mode signal to an in-plane optical mode signal.

The disclosure relates to a method of fabricating an enhancement mode Group III-nitride HEMT device and a Group III-nitride structure fabricated therefrom. One example embodiment is a method for fabricating an enhancement mode Group III-nitride HEMT device. The method includes providing a structure. The structure includes a substrate having a main surface. The structure also includes a layer stack overlying the main surface. Each layer of the layer stack includes a Group III-nitride material. The structure further includes a capping layer on the layer stack. The method also includes forming a recessed gate region by removing, in a gate region, at least the capping layer by performing an etch process, thereby exposing a top surface of an upper layer of the layer stack. The method further includes forming a p-type doped GaN layer in the recessed gate region and on the capping layer by performing a non-selective deposition process.

A nitride semiconductor device includes: a substrate; a first nitride semiconductor layer (1) located over the substrate; a second nitride semiconductor layer (2) located over the first nitride semiconductor layer (1), having a larger band gap than the first nitride semiconductor layer (1), and having a recess (11) penetrating into the first nitride semiconductor layer (1); and a third nitride semiconductor layer (12) continuously covering the second nitride semiconductor layer (2) and the recess (11), and having a larger band gap than the first nitride semiconductor layer (1); a gate electrode (5) located above a portion of the third nitride semiconductor layer (12) over the recess (11); and a first ohmic electrode (4a) and a second ohmic electrode (4b) located on opposite sides of the gate electrode (5).

A semiconductor device comprises a semiconductor body with a front face and a back face, having an active zone located at the front face, a front surface metallization layer having a front face and a back face directed towards the active zone, the front surface metallization layer being provided on the front face of the semiconductor body and being electrically connected to the active zone, and a first barrier layer, comprising amorphous metal nitride, located between the active zone and the metallization layer. Further, a method for producing such a device is provided.