A method of producing a semiconductor device structure, comprising: providing a SiC substrate, and providing an In x2 Al y2 Ga 1-x2-y2 N nucleation layer, wherein x2<0.05, y2>0.50, preferably x2<0.03 and y2>0.70 and most preferably x2<0.01 and y2>0.90, and x2+y2≤1, on the SiC substrate, providing an In x1 Al y1 Ga 1-x1-y1 N buffer layer, wherein x1<0.05, y1<0.50 and x1+y1≤1, preferably x1<0.03 and y1<0.30 and most preferably x1<0.01 and y1<0.10, wherein the pressure during growth of the nucleation layer and of the buffer layer is 10 x 10 2 Pa to 200 x 10 2 Pa, preferably 20 x 10 2 Pa to 100 x 10 2 Pa, most preferably 40 x 10 2 Pa to 60 x 10 2 Pa, the starting temperature upon growth of the nucleation layer is 800 °C to 1100 °C, preferably 900 °C-1100 °C, most preferably 950 °C-1050 °C, and the nucleation layer and the buffer layer is grown by Metal Organic Chemical Vapor Deposition, MOCVD, or Metal Organic Vapor Phase Epitaxy, MOVPE, wherein the temperature during growth of the nucleation layer is ramped up by 5-25 °C/min, preferably by 7-20 °C/min and most preferably by 10-15 °C/min, for a time period of 2 min to 20 min, the buffer layer is provided to a thickness of 1 to 4 μm, preferably 1.3 to 3 μm and most preferably 1.5 to 2 μm, the nucleation layer is provided to a thickness of 10-100 nm, preferably 10-50 nm and most preferably 10-40 nm, and the nucleation layer is provided so that it is fully strained, wherein an in-plane lattice constant of the nucleation layer is exactly the same, or exactly the same +/- 0.15 %, preferably +/- 0.05 % or +/- 0.02 %, as an in-plane lattice constant of the SiC substrate. providing a SiC substrate, and providing an In x2 Al y2 Ga 1-x2-y2 N nucleation layer, wherein x2<0.05, y2>0.50, preferably x2<0.03 and y2>0.70 and most preferably x2<0.01 and y2>0.90, and x2+y2≤1, on the SiC substrate, providing an In x1 Al y1 Ga 1-x1-y1 N buffer layer, wherein x1<0.05, y1<0.50 and x1+y1≤1, preferably x1<0.03 and y1<0.30 and most preferably x1<0.01 and y1<0.10, wherein the pressure during growth of the nucleation layer and of the buffer layer is 10 x 10 2 Pa to 200 x 10 2 Pa, preferably 20 x 10 2 Pa to 100 x 10 2 Pa, most preferably 40 x 10 2 Pa to 60 x 10 2 Pa, the starting temperature upon growth of the nucleation layer is 800 °C to 1100 °C, preferably 900 °C-1100 °C, most preferably 950 °C-1050 °C, and the nucleation layer and the buffer layer is grown by Metal Organic Chemical Vapor Deposition, MOCVD, or Metal Organic Vapor Phase Epitaxy, MOVPE, wherein the temperature during growth of the nucleation layer is ramped up by 5-25 °C/min, preferably by 7-20 °C/min and most preferably by 10-15 °C/min, for a time period of 2 min to 20 min, the buffer layer is provided to a thickness of 1 to 4 μm, preferably 1.3 to 3 μm and most preferably 1.5 to 2 μm, the nucleation layer is provided to a thickness of 10-100 nm, preferably 10-50 nm and most preferably 10-40 nm, and the nucleation layer is provided so that it is fully strained, wherein an in-plane lattice constant of the nucleation layer is exactly the same, or exactly the same +/- 0.15 %, preferably +/- 0.05 % or +/- 0.02 %, as an in-plane lattice constant of the SiC substrate.