A high electron mobility transistor includes a stack of layers including a passivation layer and a heterojunction including a first semiconductor layer, a second semiconductor layer and a two-dimensional electron gas at the interface thereof, one surface of the passivation layer being in contact with the first semiconductor layer; a source metal contact and/or a drain metal contact and a gate electrode; an n+ doped zone situated inside the heterojunction; the source metal contact and/or the drain metal contact being positioned at the level of a recess formed in the stack of layers, the source metal contact and/or said drain metal contact having a thickness defined by an upper face and a lower face substantially parallel to the plane of the layers, the upper face being planar, the lower face being in contact with the n+ doped zone and below the interface between the first and second semiconductor layers.

A nitride semiconductor device includes a substrate, a drift layer and a block layer sequentially provided above the substrate, a gate opening penetrating through a block layer and reaching a drift layer, an electron transit layer and an electron supply layer sequentially provided above the block layer and along the inner surface of the gate opening, a gate electrode provided to cover the gate opening, a source opening penetrating through an electron supply layer and an electron transit layer and reaching the block layer, a source electrode provided in the source opening, and a drain electrode on the rear surface side of the substrate. Seen in a plan view, at least part of an outline of an end of the gate opening in the longitudinal direction follows an arc or an elliptical arc.

Structures for suppressing parasitic acoustic waves in semiconductor structures and integrated circuit devices are described. Such integrated circuit devices can, typically, produce undesirable acoustic wave resonances, and the acoustic waves can degrade the performance of the devices. In that context, some embodiments described herein relate to spoiling a conductive path that participates in the generation of acoustic waves. Some embodiments relate to spoiling acoustic characteristics of an acoustic resonant structure that may be present in the vicinity of the device. Combined embodiments that spoil the conductive path and acoustic characteristics are also possible.

Embodiments are directed to high electron mobility transistor (HEMT) devices and methods. One such HEMT device includes a substrate having a first surface, and first and second heterostructures on the substrate and facing each other. Each of the first and second heterostructures includes a first semiconductor layer on the first surface of the substrate, a second semiconductor layer on the first surface of the substrate, and a two-dimensional electrode gas (2DEG) layer between the first and second semiconductor layers. A doped semiconductor layer is disposed between the first and second heterostructures, and a source contact is disposed on the first heterostructure and the second heterostructure.

There is provided a semiconductor layer structure (100) comprising: a Si substrate (102) having a top surface (104); a first semiconductor layer (110) arranged on said substrate, the first semiconductor layer comprising a plurality of vertical nanowire structures (112) arranged perpendicularly to said top surface of said substrate, the first semiconductor layer comprising AlN; a second semiconductor layer (120) arranged on said first semiconductor layer laterally and vertically enclosing said nanowire structures, the second semiconductor layer comprising Al.sub.xGa.sub.1-xN, wherein 0≤x≤0.95; a third semiconductor layer (130) arranged on said second semiconductor layer, the third semiconductor layer comprising Al.sub.yGa.sub.1-yN, wherein 0≤y≤0.95; and a fourth semiconductor layer (140) arranged on said third semiconductor layer, the fourth semiconductor layer comprising GaN. There is also provided a high-electron-mobility transistor device and methods of producing such structures and devices.

This disclosure describes the structure of a transistor that provides improved performance by reducing the off-state capacitance between the source and the drain by using a cap layer to extend the electrical distance between the gate and the source and drain contacts. In certain embodiments, a dielectric layer may be disposed between the gate electrode and the cap layer and vias are created in the dielectric layer to allow the gate electrode to contact the cap layer at select locations. In some embodiments, the gate electrode is offset from the cap layer to allow a more narrow cap layer and to allow additional space between the gate electrode and the drain contact facilitating the inclusion of a field plate. The gate electrode may be configured to only contact a portion of the cap layer.

A semiconductor structure includes a substrate, a passive device and an active device over the substrate. The active device is formed in the first region of the substrate, and the passive device is formed in the second region of the substrate. The semiconductor structure further includes a passivation layer that covers the top surface of the passive device. The passivation layer has an opening that exposes the active device.

A nitride semiconductor device having a field effect gate is disclosed. The disclosed nitride semiconductor device includes a high-resistance material layer including a Group III-V compound semiconductor, a first channel control layer on the high-resistance material layer and including a Group III-V compound semiconductor of a first conductivity type, a channel layer on the channel layer control layer and including a nitride semiconductor of a second conductivity type opposite to the first conductivity type, and a gate electrode having a contact of an ohmic contact type with the first channel control layer.

A semiconductor device includes a nitride semiconductor laminated structure formed on a substrate, a source electrode formed on the nitride semiconductor laminated structure, a drain electrode and a gate electrode, and a surface protection film covering the nitride semiconductor laminated structure. the nitride semiconductor laminated structure includes: a first nitride semiconductor layer formed on the substrate; and a second nitride semiconductor layer formed on the first nitride semiconductor layer and having a composition different from the first nitride semiconductor layer. The surface protection film includes: a first insulating film formed to have contact with the gate electrode; and a second insulating film formed adjacent to the first insulating film and having a higher carbon concentration than the first insulating film.

A high electron mobility transistor and a method of manufacturing the same are disclosed. The high electron mobility transistor includes a channel layer, a channel supplying layer causing generation of a two-dimensional electron gas (2DEG) in the channel layer, a source electrode and a drain electrode provided on respective sides of the channel supplying layer, a depletion forming layer provided on the channel supplying layer to form a depletion region in the 2DEG, a gate electrode provided on a portion of the depletion forming layer, and a current limiting layer provided to contact the gate electrode on another portion of the depletion forming layer. The current limiting layer limits a current flow from the gate electrode to the depletion forming layer according to a voltage applied to the gate electrode.