In some embodiments, the present disclosure relates to a semiconductor device. The semiconductor device includes a channel layer disposed over a base substrate, and an active layer disposed on the channel layer. A source contact and a drain contact are over the active layer and are laterally spaced apart from one another along a first direction. A gate electrode is arranged on the active layer between the source contact and the drain contact. A passivation layer is arranged on the active layer and laterally surrounds the source contact, the drain contact, and the gate electrode. A conductive structure is electrically coupled to the source contact and is disposed laterally between the gate electrode and the source contact. The conductive structure extends along an upper surface and a sidewall of the passivation layer.

A transistor device includes a semiconductor structure comprising a channel layer and a barrier layer; source and drain contacts on the semiconductor structure; and a gate on the semiconductor structure between the source and drain contacts. A first portion of the barrier layer extending between the source or drain contact and the gate has a first thickness, a second portion of the barrier layer between the gate and the channel layer has a second thickness, and the first thickness is about 1.5 times to 4 times greater than the second thickness. Related methods of fabrication using a looped recess process are also discussed.

A high electron mobility transistor (HEMT) includes a group III-V channel layer, a passivation layer, a group III-V barrier layer, a gate structure, and a source/drain electrode. The passivation layer is disposed on the group III-V channel layer and includes a gate contact hole and a source/drain contact hole, and the group III-V barrier layer is disposed between the group III-V channel layer and the passivation layer. The gate structure includes group III-V gate layer, a gate etch stop layer, and a gate electrode which are stacked in sequence. The gate electrode is disposed in the gate contact hole and conformally covers a portion of the top surface of the passivation layer. The source/drain electrode is disposed in the source/drain contact hole and conformally covers another portion of the top surface of the passivation layer.

A semiconductor device includes an n-type semiconductor layer; a first metal layer provided on the n-type semiconductor layer, the first metal layer including first atoms capable of being n-type impurities in the n-type semiconductor layer; a second metal layer provided on the first metal layer, the second metal layer including titanium atoms; a third metal layer provided on the second metal layer; and a second atom capable of being a p-type impurity in the n-type semiconductor layer. The second atom and a part of the titanium atoms are included in a vicinity of an interface between the first metal layer and the second metal layer.

An HEMT device of a normally-on type, comprising a heterostructure; a dielectric layer extending over the heterostructure; and a gate electrode extending right through the dielectric layer. The gate electrode is a stack, which includes: a protection layer, which is made of a metal nitride with stuffed grain boundaries and extends over the heterostructure, and a first metal layer, which extends over the protection layer and is completely separated from the heterostructure by said protection layer.

Embodiments herein describe techniques for a semi-conductor device comprising a channel having a first semiconductor material; a source contact coupled to the channel, comprising a first Heusler alloy; and a drain contact coupled to the channel, comprising a second Heusler alloy. The first Heusler alloy is lattice-matched to the first semiconductor material within a first predetermined threshold. A first Schottky barrier between the channel and the source contact, and a second Schottky barrier between the channel and the drain contact are negative, or smaller than another predetermined threshold. The source contact and the drain contact can be applied to a strained silicon transistor, an III-V transistor, a tunnel field-effect transistor, a dichalcogenide (MX2) transistor, and a junctionless nanowire transistor.

This invention concerns a gate structure and a process for its manufacturing. In particular, the present invention concerns the gate structuring of a field effect transistor with reduced thermo-mechanical stress and increased reliability (lower electromigration or diffusion of the gate metal). The gate structure according to the invention comprises a substrate; an active layer disposed on the substrate; an intermediate layer disposed on the active layer, the intermediate layer-having a recess extending through the entire intermediate layer towards the active layer; and a contact element which is arranged within the recess, the contact element completely filling the recess and extending to above the intermediate layer, the contact element resting at least in sections directly on the intermediate layer; the contact element being made of a Schottky metal and the contact element having an interior cavity completely enclosed by the Schottky metal.

Example embodiments relate to enhancement-mode high electron mobility transistors. One embodiment includes a method for manufacturing an enhancement-mode high electron mobility transistor. The method includes providing a stack of layers. The stack of layers includes a substrate, a III-V channel layer over the substrate, a III-V barrier layer on the channel layer, a p-doped III-V layer on the III-V barrier layer, and a Schottky contact interlayer on the p-doped III-V layer. The p-doped III-V layer has a first surface area. The Schottky contact interlayer has a second surface area. The second surface area is less than the first surface area. The second surface area leaves a peripheral part of a top surface of the p-doped III-V layer uncovered. The method also includes depositing a metal gate on the Schottky contact interlayer.

A microwave transistor has a patterned region between a source and a drain on a barrier layer. Within the patterned region, the surface of the barrier layer partially recessed downwards in the thickness direction to form a plurality of grooves. A gate covers the patterned region. The length of the gate is greater than the lengths of the grooves in the length direction of the gate, so as to completely cover the grooves. In one aspect, by arranging the grooves, the gate control capability of a component is improved and the short-channel effect is suppressed; in another aspect, an original heterostructure below the gate is preserved; in this way, the reduction of the conductive capability due to the reduction of the two-dimensional electron gas density is avoided; and accordingly the current output capability of the component is ensured while the short-channel effect is suppressed.

A process for producing a component includes a structure made of III-V material(s) on the surface of a substrate, the structure comprising at least one upper contact level defined on the surface of a first III-V material and a lower contact level defined on the surface of a second III-V material, comprising: successive operations of encapsulation of the structure with at least one dielectric; making primary apertures in a dielectric for the two contacts; making secondary apertures in a dielectric for the two contacts; at least partial filling of the apertures with at least one metallic material so as to produce upper contact bottom metallization and at least one upper contact pad in contact with the metallization for each of said contacts. A component produced by the process is also provided. The component may be a laser diode.