A method of manufacturing a silicon carbide semiconductor device is provided. The method suppresses the increase in the number of manufacturing steps and is capable of suppressing the degradation of ohmic characteristics of an alloy layer with respect to a semiconductor substrate. The method includes a step of forming a metal layer made of a first metal on a semiconductor substrate made of silicon carbide; a step of forming a metal nitride film obtained by nitriding a second metal on the metal layer; a step of directing a laser light through the metal nitride film to form a layer of an alloy of silicon carbide in the semiconductor substrate and the first metal in the metal layer; and a step of forming an electrode on the metal nitride film.

An HEMT includes a semiconductor body, which includes a semiconductor heterostructure, and a conductive gate region. The gate region includes: a contact region, which is made of a first metal material and contacts the semiconductor body to form a Schottky junction; a barrier region, which is made of a second metal material and is set on the contact region; and a top region, which extends on the barrier region and is made of a third metal material, which has a resistivity lower than the resistivity of the first metal material. The HEMT moreover comprises a dielectric region, which includes at least one front dielectric subregion, which extends over the contact region, delimiting a front opening that gives out onto the contact region; and wherein the barrier region extends into the front opening and over at least part of the front dielectric subregion.

A high electron mobility transistor (HEMT) includes an active region, in which a channel is formed, and a field region surrounding the active region. The HEMT may include a channel layer; a barrier layer on the channel layer and configured to induce a two-dimensional electron gas (2DEG) in the channel layer; a source and a drain on the barrier layer in the active region; and a gate on the barrier layer. The gate may protrude from the active region to the field region on the barrier layer. The gate may include a first gate and a second gate. The first gate may be in the active region and the second gate may be in the boundary region between the active region and the field region. A work function of the second gate may be different from a work function of the first gate.

The present invention discloses a GaN HEMT transistor with impact energy release capability for use in aerospace irradiation environment and preparation method thereof. The transistor includes a substrate layer, a gallium nitride layer, a barrier layer, and a gate structure successively arranged from bottom to top. The gallium nitride layers on both sides of the barrier layer are respectively provided with a source electrode and a drain electrode on the top surface. The gate structure is located near the source electrode and includes a p-type gallium nitride layer, a dielectric layer, an Ohmic metal pillar, and a Schottky metal layer. The present invention solves the breakdown problem caused by the inability to release impact energy during the switching process by introducing an asymmetric multi-integrated gate structure.

Disclosed are devices and methods related to metallization of semiconductors. A metalized structure can include a first titanium (Ti) layer disposed over a compound semiconductor, a first barrier layer disposed over the first Ti layer, a second Ti layer disposed over the first barrier layer, and a copper (Cu) layer disposed over the second Ti layer. The second Ti layer can be configured to inhibit or reduce alloying of the Cu layer and the first barrier layer. The first Ti layer, the first barrier layer, and the second Ti layer can be configured to yield a barrier between the Cu layer and an ohmic metal layer formed on the compound semiconductor. The metalized structure can further include a third Ti layer disposed over the Cu layer and a second barrier layer disposed over the third Ti layer. The first and second barrier layers can include platinum (Pt) and/or palladium (Pd).

A number of variations may include a method that may include depositing a first layer on a first semiconductor epi layer (epitaxial layer) in an overlying position with respect to at least one trench structure formed in the first semiconductor epi layer. The first layer may include a first metal and a second metal. A second layer may comprise a material constructed and arranged to scavenge silicon migrating from the first semiconductor epi layer during annealing may be deposited over the first layer. The first semiconductor epi layer may be subjected to at least a first annealing act to provide a first structure. At least a portion of the first structure may be stripped to remove any of the first layer not reacted with silicon to form a silicide during the first annealing act.

Field-plate structures are disclosed for electrical field management in semiconductor devices. A field-plate semiconductor structure includes a semiconductor substrate, a source ohmic contact, a drain ohmic contact, and a gate contact disposed over a gate region between the source ohmic contact and the drain ohmic contact, and a source field plate connected to the source ohmic contact. A field-plate dielectric is disposed over the semiconductor substrate. An encapsulating dielectric is disposed over the gate contact, wherein the encapsulating dielectric covers a top surface of the gate contact. The source field plate is disposed over the field-plate dielectric in a field plate region, from which the encapsulating dielectric is absent.

A diode includes a two-dimensional electron gas formed in a heterojunction defined between first and second semiconductor material layers. First and second layers of insulating material are disposed on the second semiconductor layer. First and second electrodes are disposed in the second layer of insulating material. The first electrode is coupled to the second semiconductor material layer. The second electrode is coupled to the heterojunction. Third and fourth layers of insulating material are disposed on the second insulating layer. A first via is disposed in the fourth layer of insulating material and coupled to the second electrode. A first field plate is disposed in the fourth layer of insulating material. An edge of the first field plate laterally extends towards first via. The first via is separated from an edge of the first via. The first field plate is coupled to the first electrode.

A semiconductor device comprises: a substrate; a multilayer semiconductor layer located on the substrate; a source located on the multilayer semiconductor layer, the source including a first source portion inside an active region and a second source portion inside a passive region; a drain located on the multilayer semiconductor layer, the drain including a first drain portion inside the active region and a second drain region inside the passive region; a gate located on the multilayer semiconductor layer, the gate including a first gate portion inside the active region and a second gate portion inside the passive region, and the first gate portion being in a form of interdigital among the first source portion and the first drain portion; and a heat dissipating layer disposed at one or more of the first source portion, the first drain portion, the first gate portion, the second source portion, the second drain portion and the second gate portion.

A method for manufacturing nitride semiconductor device includes a second step of forming, on a gate layer material film, a gate electrode film that is a material film of a gate electrode, a third step of selectively etching the gate electrode film to form the gate electrode of a ridge shape, and a fourth step of selectively etching the gate layer material film to form a semiconductor gate layer of a ridge shape with the gate electrode disposed at a width intermediate portion of a front surface thereof. The third step includes a first etching step for forming a first portion from an upper end to a thickness direction intermediate portion of the gate electrode and a second etching step being a step differing in etching condition from the first etching step and being for forming remaining second portion of the gate electrode.