A semiconductor device includes a nucleation layer, a buffer layer, a first nitride-based semiconductor layer, a second nitride-based semiconductor layer, S/D electrodes, and a gate electrode. The nucleation layer includes a composition that includes a first element. The buffer layer includes a III-V compound which includes the first element. The buffer layer has a concentration of the first element oscillating within the buffer layer, such that the concentration of the first element varies as an oscillating function of a distance within a thickness of the buffer layer. A first oscillation rate between a first reference point and a second reference point within the buffer layer is less than a second oscillation rate between the second reference point and a third reference point within the buffer layer. The first and second nitride-based semiconductor layer, S/D electrodes, and a gate electrode are disposed on the buffer layer.

A semiconductor device includes a nucleation layer, a buffer layer, a first nitride-based semiconductor layer, a second nitride-based semiconductor layer, S/D electrodes, and a gate electrode. The nucleation layer includes a composition that includes a first element. The buffer layer includes a III-V compound which includes the first element. The buffer layer is disposed on and forms an interface with the nucleation layer. The buffer layer has a concentration of the first element oscillating within the buffer layer, such that the concentration of the first element varies as an oscillating function of a distance within a thickness of the buffer layer. An oscillation rate in the concentration of the first element per unit thickness of the buffer layer varies with respect to a first reference point within the buffer layer. The first and second nitride-based semiconductor layer, S/D electrodes, and a gate electrode are disposed on the buffer layer.

Devices and methods for switch body connections to achieve soft breakdown. In some embodiments, a radio-frequency switching device can include an assembly of source, gate, and drain implemented on an active region, a first body contact implemented at a first end of the assembly, and a second body contact implemented at a second end of the assembly. The second end can be distal from the first end along a width of the radio-frequency switching device.

An integrated circuit includes a first time delay circuit, a second time delay circuit, and a master-slave flip-flop having a gated input circuit and a transmission gate. The transmission gate is configured to receive the first clock signal and the second clock signal to control a transmission state of the transmission gate. The gated input circuit is configured to have an input transmission state controlled by the third clock signal at the second output of the second time delay circuit. The second time delay circuit further includes a second gate-conductor and a second gate via-connector in direct contact with the second gate-conductor. The second gate-conductor intersects a first-type active region structure and a second-type active region structure in a second area, and wherein at least a portion of the second gate via-connector is atop the second-type active region structure.

A transistor device according to some embodiments includes a channel layer, a barrier layer on the channel layer, and source and drain contacts on the barrier layer, and a gate contact on the barrier layer between the source and drain contacts. The channel layer includes a sub-layer having an increased doping concentration level relative to a remaining portion of the channel layer. The presence of the sub-layer may reduce drain lag without substantially increasing gate lag.

An apparatus for reducing lag includes a substrate; a group III-Nitride barrier layer; a source electrically coupled to the group III-Nitride barrier layer; a gate on the group III-Nitride barrier layer; a drain electrically coupled to the group III-Nitride barrier layer; a p-region being arranged at or below the group III-Nitride barrier layer; and a gate control circuit configured to control a gate voltage of the gate. Additionally, at least a portion of the p-region is arranged vertically below at least one of the following: the source, the gate, and an area between the gate and the drain.

A method of manufacturing a High-Electron-Mobility Transistor (HEMT) includes: preparing a substrate; forming a first buffer over the substrate; forming a second buffer over the first buffer, wherein forming the second buffer includes doping a first thickness of a material such as gallium nitride (GaN) with a first concentration of a dopant such as carbon, and doping a second thickness of the material with a second concentration of the dopant such that the second concentration of dopant has a gradient though the second thickness which progressively decreases in a direction away from the first thickness; forming a channel layer such as a GaN channel over the second buffer; forming a barrier layer such as aluminum gallium nitride (AlGaN) over the channel layer; and forming drain, source and gate terminals for the HEMT.

A semiconductor device includes a semiconductor substrate, an Aluminum Gallium-Nitride (AlGaN) back-barrier layer formed above the semiconductor substrate, and a GaN channel layer formed on the AlGaN back-barrier layer. A two-dimensional hole gas (2DHG) is formed at an interface between the GaN channel layer and the AlGaN back-barrier layer, and a p-type doped region is formed above the semiconductor substrate and next to the GaN channel layer and the AlGaN back-barrier layer. The p-type doped region is configured to provide an ohmic contact for the 2DHG. The p-type doped region comprises Magnesium as a p-type dopant. The p-type doped region comprises one or more hollow chambers extending from the top face of the p-type doped region. The hollow chambers are configured to form an escape path for Hydrogen atoms which are formed during a dopant activation of the p-type doped region during fabrication of the semiconductor device.

A semiconductor device includes: a Si substrate; a back electrode provided below the Si substrate; a SiC layer provided above the Si substrate; a nitride semiconductor layer provided above the SiC layer; a source electrode and a drain electrode provided above the nitride semiconductor layer; a gate electrode in contact with the nitride semiconductor layer; an intermediate layer provided in an opening that creates an opening in the SiC layer and the nitride semiconductor layer; a metal layer provided above the opening so as to cover the intermediate layer; and a conductor that is provided inside a through via that penetrates the intermediate layer and the Si substrate and is electrically connected with the back electrode and the metal layer. The intermediate layer is a metal nitride layer or a silicon oxide layer.

A semiconductor component may include a substrate, a first buffer layer, a second buffer layer, and a channel layer that are disposed in a stacked manner. The first buffer layer includes at least two first buffer sub-layers that are disposed in the stacked manner, and a second buffer sub-layer is disposed in the stacked manner between the at least two first buffer sub-layers. A first material is used for each of the at least two first buffer sub-layers, and a second material is used for the second buffer sub-layer. Elements included in the first material are not totally the same as elements included in the second material.