A method for forming a high electron mobility transistor is disclosed. A mesa structure having a channel layer and a barrier layer is formed on a substrate. The mesa structure has two first edges extending along a first direction and two second edges extending along a second direction. A passivation layer is formed on the substrate and the mesa structure. A first opening and a plurality of second openings connected to a bottom surface of the first opening are formed and through the passivation layer, the barrier layer and a portion of the channel layer. In a top view, the first opening exposes the two first edges of the mesa structure without exposing the two second edges of the mesa structure. A metal layer is formed in the first opening and the second openings thereby forming a contact structure.

A method for fabricating a semiconductor device includes the steps of first providing a substrate having a high electron mobility transistor (HEMT) region and a capacitor region, forming a buffer layer on the substrate, forming a mesa isolation on the HEMT region, forming a HEMT on the mesa isolation, and then forming a capacitor on the capacitor region. Preferably, a bottom electrode of the capacitor contacts the buffer layer directly.

A method for fabricating a semiconductor device includes the steps of first providing a substrate having a high electron mobility transistor (HEMT) region and a capacitor region, forming a buffer layer on the substrate, forming a mesa isolation on the HEMT region, forming a HEMT on the mesa isolation, and then forming a capacitor on the capacitor region. Preferably, a bottom electrode of the capacitor contacts the buffer layer directly.

A semiconductor device has a first region and a second region including a first structural layer, a second structural layer, first electrode structure and second electrode structure. The material of the first structural layer comprises monocrystalline diamond, and a portion of the first structural layer located in the first region is electrically isolated from a portion located in the second region. The second structural layer is disposed on the first structural layer, and located in the first region, and forms a heterojunction structure with the first structural layer; the material of the second structural layer includes a monocrystalline AlN film or a doped monocrystalline AlN film. The first electrode structure comprises a first source electrode, a first gate electrode and a first drain electrode. The second electrode structure comprises a second source electrode, a second gate electrode and a second drain electrode.

The present invention provides a nitride semiconductor device, including: a silicon substrate; a first lateral transistor over a first region of the silicon substrate and including: a first nitride semiconductor layer formed over the silicon substrate; and a first gate electrode, a first source electrode and a first drain electrode formed over the first nitride semiconductor layer; a second lateral transistor over a second region of the silicon substrate and including: a second nitride semiconductor layer formed over the silicon substrate; and a second gate electrode, a second source electrode and a second drain electrode formed over the second nitride semiconductor layer; a first separation trench formed over a third region; a source/substrate connecting via hole formed over the third region; a first interlayer insulating layer formed over the first source electrode and the second source electrode; and a second interlayer insulating layer formed in the first separation trench.

An integrated circuit (IC) includes a lower group III-N layer having a first composition over a substrate, and an upper group III-N layer having a different second composition over the lower group III-N layer. A gate electrode of a High Electron Mobility Transistor (HEMT) is located over the upper group III-N layer. First and second resistor contacts make a conductive connection to the lower group III-N layer. An unbiased group III-N cover layer is located on the upper group III-N layer in a resistor area including a high Rs 2-DEG resistor, where the unbiased group III-N cover layer is positioned between the first and second contacts.

An integrated circuit (IC) includes a lower group III-N layer having a first composition over a substrate, and an upper group III-N layer having a different second composition over the lower group III-N layer. A gate electrode of a High Electron Mobility Transistor (HEMT) is located over the upper group III-N layer. First and second resistor contacts make a conductive connection to the lower group III-N layer. An unbiased group III-N cover layer is located on the upper group III-N layer in a resistor area including a high Rs 2-DEG resistor, where the unbiased group III-N cover layer is positioned between the first and second contacts.

Quantum dot devices, and related systems and methods, are disclosed herein. In some embodiments, a quantum dot device may include a quantum well stack; a plurality of first gates above the quantum well stack; and a plurality of second gates above the quantum well stack; wherein the plurality of first gates are arranged in electrically continuous rows extending in a first direction, and the plurality of second gates are arranged in electrically continuous rows extending in a second direction perpendicular to the first direction.

Quantum dot devices, and related systems and methods, are disclosed herein. In some embodiments, a quantum dot device may include a quantum well stack; a plurality of first gates above the quantum well stack; and a plurality of second gates above the quantum well stack; wherein the plurality of first gates are arranged in electrically continuous rows extending in a first direction, and the plurality of second gates are arranged in electrically continuous rows extending in a second direction perpendicular to the first direction.

The present disclosure provides a semiconductor device and a fabrication method thereof. The semiconductor device includes a III-nitride layer, a gate, a connection structure, and a gate bus. The gate is disposed over the III-nitride layer. The connection structure is disposed over the gate. The gate bus extends substantially in parallel to the gate and disposed over the connection structure from a top view perspective. The gate bus is electrically connected to the gate through the connection structure.