Semiconductor structure comprising III-N material
A semiconductor structure comprising III-N materials, includes: a support substrate; a main layer of III-N material, the main layer comprising a first section disposed on the support substrate and a second section disposed on the first section; an inter-layer of III-N material, disposed between the first section and the second section in order to compress the second section of the main layer, wherein the structure's inter-layer consists of a lower layer disposed on the first section and an upper layer disposed on the lower layer and formed by a superlattice.
1. A semiconductor structure including III-N materials, comprising:
a support substrate;
a main layer made of III-N material, the main layer having a first section disposed on the support substrate and a second section disposed over the first section;
an interlayer made of III-N material disposed between the first section and the second section for compressing the second section of the main layer, wherein the interlayer comprises:
a lower layer disposed on the first section of the main layer; and
an upper layer disposed on and in contact with the lower layer formed by a superlattice, wherein the lower layer consists essentially of a homogeneous layer or a superlattice which is different from the superlattice constituting the upper layer, having a dislocation density greater than that of the upper layer and a lattice parameter smaller than a lattice parameter of the material forming the upper layer, the superlattice constituting the upper layer and, where appropriate, the superlattice constituting the lower layer being formed by a repetition of a pattern comprising at least two layers of different types; and wherein each layer making up the pattern has a thickness of between 0.5 nm and 50 nm, the interlayer has a thickness of between 200 nm and 1000 nm, and the upper layer comprises a p-type dopant of carbon, iron or magnesium in a concentration of between 5×10 18 and 5x10 19 at/cm 3 to make the layer resistive.
2. The semiconductor structure of claim 1 , wherein the lattice parameter of the material forming the upper layer is smaller than the lattice parameter of the material forming the second section of the main layer.
3. The semiconductor structure of claim 1 , wherein the main layer and the interlayer are monocrystalline.
4. The semiconductor structure of claim 1 , further comprising a second interlayer on the second section of the main layer and a third section of the main layer disposed on the second interlayer.
5. The semiconductor structure of claim 4 , wherein the second interlayer is formed by a uniform layer, a superlattice, or a combination thereof.
6. The semiconductor structure of claim 1 , wherein the support substrate has a lower coefficient of thermal expansion than the main layer.
7. A semiconductor wafer comprising the semiconductor structure of claim 1 .
8. An integrated circuit device comprising the semiconductor structure of claim 1 .