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 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 greater 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 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 group III element and is devoid of a second group III element. The buffer layer includes a III-V compound which includes the first and second group III elements. The buffer layer has an element ratio of the first group III element to the second group III 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. 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 group III element and is devoid of a second group III element. The buffer layer includes a III-V compound which includes the first and second group III elements. The buffer layer has a variable concentration of the second group III element that incrementally increases and then decrementally decreases 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. 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 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. Spacings among adjacent peaks of the oscillating function change from narrow to wide 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.

A semiconductor device includes a nucleation layer, a first buffer layer, a first nitride-based semiconductor layer, and a second buffer layer. The nucleation layer includes a compound which includes a first element. The first buffer layer includes a III-V compound which includes the first element. A concentration of the first element varies with respect to a first reference point within the first buffer layer. The first nitride-based semiconductor layer is disposed on the first buffer layer. The second buffer layer includes a III-V compound which includes a second element different than the first element. The second buffer layer is disposed on and forms an interface with the first nitride-based semiconductor layer. A concentration of the second element varies to cyclically oscillate as a function of a distance within a thickness of the second buffer layer, which occurs with respect to a second reference point within the second buffer 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 group III element and is devoid of a second group III element. The buffer layer includes a III-V compound which includes the first and second group III elements. The buffer layer has an element ratio of the first group III element to the second group III element that incrementally increases and then decrementally decreases 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. The S/D electrodes and a gate electrode are disposed over the second nitride-based semiconductor layer.

Embodiments of the present application provide a semiconductor structure and a manufacturing method therefor. A buffer layer is disposed on a substrate layer, and the buffer layer includes a first buffer layer and a second buffer layer. By doping a transition metal in the first buffer layer, a deep level trap may be formed to capture background electrons, and diffusion of free electrons toward the substrate may also be avoided. By decreasing a doping concentration of the transition metal in the second buffer layer, a tailing effect is avoided and current collapse is prevented. By doping periodically the impurity in the buffer layer, the impurity may be as an acceptor impurity to compensate the background electrons, and then a concentration of the background electrons is reduced. By using the periodic doping method, dislocations, caused by doping, in the buffer layer may be effectively reduced.

The present invention provides a nitride semiconductor substrate suitable for a high frequency device. The nitride semiconductor substrate has a substrate, a buffer layer made of group 13 nitride semiconductors, and an active layer made of group 13 nitride semiconductors in this order, wherein the substrate is composed of a first substrate made of polycrystalline aluminum nitride, and a second substrate made of Si single crystal having a specific resistance of 100 Ω.Math.cm or more, formed on the first substrate, the average particle size of AlN constituting the first substrate is 3 to 9 μm, and preferably, the second substrate grown by the MCZ method has an oxygen concentration of 1E+18 to 9E+18 atoms/cm.sup.3 and a specific resistance of 100 to 1000 Ω.Math.cm.

The present disclosure provides a semiconductor device, a manufacturing method, and electronic equipment. The semiconductor device comprising: a substrate; an interface, for generating two-dimensional charge carrier gas; a first electrode and a second electrode; and a first semiconductor layer of a first type doping formed on the substrate, wherein first regions and a second region are formed in the first semiconductor layer, wherein in the first regions, the dopant atoms of the first type do not have electrical activity, and in the second region, the dopant atoms of the first type have electrical activity; and the second region comprises a portion coplanar with the first regions. The semiconductor device can not only avoid damage to the crystal structure, but also can be easily realized in the processing, and it can maintain good transport properties of the two-dimensional charge carrier gas, which is beneficial to the improvement of device performance.