Provided is a semiconductor substrate with a balance stress. The semiconductor substrate includes a ceramics base, a nucleation layer and a first buffer layer doped with a first dopant. The ceramics base has an off-cut angle other than 0 degree. The nucleation layer is disposed on the ceramics base. The first buffer layer is disposed on the nucleation layer. The first dopant includes C, Fe or a combination thereof. The first buffer layer provides compressive stress to the ceramic base. The concentration of the first dopant in the first buffer layer is increased away from the ceramics base. The curvature of the semiconductor substrate is between 16 km.sup.−1 and −16 km.sup.−1.

A semiconductor apparatus includes a plurality of semiconductor devices with a single substrate, a plurality of trench regions, each trench region including a trench, wherein the single substrate includes a substrate layer, a first epitaxial layer of a first conductivity type, disposed on the substrate layer, and a second epitaxial layer of a second conductivity type, disposed on the first epitaxial layer, wherein each trench of the plurality of trench regions extends through the second epitaxial layer and into the first epitaxial layer, thereby isolating adjacent semiconductor devices of the plurality of semiconductor devices.

Electric field management techniques in GaN based semiconductors that utilize patterned regions of differing conductivity under the active GaN device, such as a GaN high electron mobility transistor (HEMT), are described. As an example, a patterned layer of oxidized silicon can be formed superjacent a layer of silicon dioxide during or prior to the heteroepitaxy of GaN or another semiconductor material. These techniques can be useful for back-side electric field management because a silicon layer, for example, can be made conductive to act as a back-side field plate.

The present disclosure provides a radio frequency device, a silicon carbide homoepitaxial substrate and a manufacturing method thereof. The manufacturing method of the silicon carbide homoepitaxial substrate includes: providing an N-type silicon carbide substrate, forming first grooves in the N-type silicon carbide substrate; forming a defect repair layer on inner walls of the first grooves and outside the first grooves, and forming second grooves in the defect repair layer corresponding to the first grooves; forming an unintentionally doped silicon carbide layer on the defect repair layer, where the second grooves are fully filled with the unintentionally doped silicon carbide layer.

A semiconductor device includes a transistor, a semiconductor layer, an active region and a conductive layer. The active region is in the semiconductor layer. The conductive layer is configured to maintain a channel in the active region when the transistor is triggered to be conducted.

A semiconductor structure includes a superlattice structure, an electrical isolation layer, a channel layer, and a composition gradient layer. The superlattice structure is disposed on a substrate, the electrical isolation layer is disposed on the superlattice structure, the channel layer is disposed on the electrical isolation layer, and the composition gradient layer is disposed between the electrical isolation layer and the superlattice structure. The composition gradient layer and the superlattice structure include a same group III element, and the atomic percentage of the same group III element in the composition gradient layer is gradually decreased in the direction from the superlattice structure to the electrical isolation layer. In addition, a high electron mobility transistor including the semiconductor structure is also provided.

A semiconductor device includes a substrate, a nucleation layer, a buffer layer, first and second nitride-based semiconductor layers, a pair of S/D electrodes, and a gate electrode. The nucleation layer is disposed on the substrate. The buffer layer includes a III-V compound which includes a first element. The buffer layer is disposed on the nucleation layer. The buffer layer has a variable concentration of the first element that decrementally decreases and then incrementally increases as a function of a distance within a thickness of the buffer layer. The first nitride-based semiconductor layer is disposed on the buffer layer. The second nitride-based semiconductor layer is disposed on the first nitride-based semiconductor layer and has a bandgap greater than a bandgap of the first nitride-based semiconductor layer. The S/D electrodes and a gate electrode are disposed over the second nitride-based semiconductor layer.

A semiconductor device includes a substrate, a nucleation layer, a buffer layer, first and second nitride-based semiconductor layers, a pair of S/D electrodes, and a gate electrode. The nucleation layer includes a compound which 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 cyclically oscillating with respect to first and second reference points within a buffer layer. The first and second reference points are respectively positioned at first and second distances from a top surface of the nucleation layer. The first nitride-based semiconductor layer is disposed on the buffer layer. The second nitride-based semiconductor layer is disposed on the first nitride-based semiconductor layer. The S/D electrodes and a gate electrode are disposed over the second nitride-based semiconductor 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 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.