A method for etching at least one layer of a gallium nitride (GaN)-based material is provided, the method including: providing the GaN-based layer having a front face; and at least one cycle including the following successive steps: modifying, by implanting hydrogen (H)- and/or helium (He)-based ions, at least some of a thickness of the GaN-based layer to form in the layer at least one modified portion extending from the front face, the implanting being carried out from a plasma, the modifying by implanting being carried out such that the modified portion extends from the front face and over a depth greater than 3 nm; oxidizing at least some of the modified portion by exposing the layer to an oxygen-based plasma, to define in the layer, at least one oxidized portion and at least one non-oxidized portion; and etching the oxidized portion selectively at the non-oxidized portion.

The present disclosure provides a high electron mobility transistor including a channel layer; a barrier layer on the channel layer and configured to induce formation of a 2-dimensional electron gas (2DEG) to the channel layer; a p-type semiconductor layer on the barrier layer; a first passivation layer on the barrier layer and including a quaternary material of Al, Ga, O, and N; a gate electrode on the p-type semiconductor layer; and a source electrode and a drain electrode provided on both sides of the barrier layer and separated from the gate electrode.

Provided are a diode and a manufacturing method therefor. The diode includes: a nitride channel layer; a nitride barrier layer, formed on the nitride channel layer; an oxidation forming layer, wherein a part of the oxidation forming layer is positioned in the nitride barrier layer, and a surface of the oxidation forming layer away from the nitride channel layer is flush with a surface of the nitride barrier layer away from the nitride channel layer; a passivation layer, formed on the nitride barrier layer, wherein the passivation layer includes a first groove penetrating through the passivation layer to expose the oxidation forming layer and a part of the nitride barrier layer; and a first electrode, formed in the first groove, wherein the first electrode is in contact with the nitride barrier layer and the oxidation forming layer.

Methods for inducing reversible or permanent conductivity in wide band gap metal oxides such as Ga.sub.2O.sub.3, using light without doping, as well as related compositions and devices, are described.

A compound semiconductor device includes a carrier supply layer, a channel layer disposed over the carrier supply layer and configured to include InGaAs, and an etching stopper layer disposed over the channel layer, and configured to include a first layer disposed over the channel layer and configured to include In.sub.x1Ga.sub.1-x1P, and a second layer disposed over the first layer and configured to include In.sub.x2Ga.sub.1-x2P, wherein x1 is greater than 0 and less than or equal to 1, x2 is greater than or equal to 0 and less than 1, and x1 is greater than x2.

A nitride-based semiconductor device includes a first nitride-based semiconductor layer, a lattice layer, a third nitride-based semiconductor layer, a first source electrode and a second electrode, and a gate electrode. The second nitride-based semiconductor layer is disposed over the first nitride-based semiconductor layer. The lattice layer is disposed between the first and second nitride-based semiconductor layers and doped to the first conductivity type. The lattice layer comprises a plurality of first III-V layers and second III-V layers alternatively stacked. Each of the first III-V layers has a high resistivity region and a current aperture enclosed by the high resistivity region. The high resistivity region comprises more metal oxides than the current aperture. At least two of the current apertures have different dimensions such that interfaces formed between the high resistivity regions and the current apertures misalign with each other. The gate electrode aligns with the current aperture.

A second semiconductor layer is oxidized through a groove and a fourth semiconductor layer is oxidized, a first oxide layer is formed, and a second oxide layer is formed. By oxidizing the entire second semiconductor layer and the fourth semiconductor layer, the first oxide layer and the second oxide layer in an amorphous state are formed.

According to one embodiment, a semiconductor device includes first to third electrodes, first and second semiconductor layers, a nitride layer, and an oxide layer. A direction from the second electrode toward the first electrode is aligned with a first direction. A position in the first direction of the third electrode is between the first electrode and the second electrode in the first direction. The first semiconductor layer includes first to fifth partial regions. The first partial region is between the fourth and third partial regions in the first direction. The second partial region is between the third and fifth partial regions in the first direction. The nitride layer includes first and second nitride regions. The second semiconductor layer includes first and second semiconductor regions. The oxide layer includes silicon and oxygen. The oxide layer includes first to third oxide regions.

A method for treating a compound semiconductor substrate, in which method in vacuum conditions a surface of an In-containing III-As, III-Sb or III-P substrate is cleaned from amorphous native oxides and after that the cleaned substrate is heated to a temperature of about 250-550° C. and oxidized by introducing oxygen gas onto the surface of the substrate. The invention relates also to a compound semiconductor substrate, and the use of the substrate in a structure of a transistor such as MOSFET.

A semiconductor device includes: a first semiconductor layer formed, on a substrate, of a nitride semiconductor; a second semiconductor layer formed, on the first semiconductor layer, of a nitride semiconductor; a source electrode formed on the second semiconductor layer; a drain electrode formed on the second semiconductor layer; a metal oxide film formed, between the source electrode and the drain electrode, on the second semiconductor layer; and a gate electrode formed on the metal oxide film. The metal oxide film includes AlO.sub.x and InO.sub.x. AlO.sub.x/InO.sub.x in the metal oxide film is greater than or equal to 3.