| 摘要 |
A semiconductor device structure comprising: a layer of III-V compound semiconductor material; a layer of polycrystalline CVD diamond material; and an interface region between the layer of III-V compound semiconductor material and the layer of polycrystalline CVD diamond material, the interface region including a diamond nucleation layer of polycrystalline CVD diamond which is formed during an initial nucleation phase of polycrystalline CVD diamond growth over a substrate comprising the layer of III-V compound semiconductor material, wherein the diamond nucleation layer is such that a Raman signal generated by a laser focused on a region comprising the diamond nucleation layer exhibits an sp3 carbon peak at 1332 cm-1 having a full width half-maximum of no more than 5.0 cm-1, wherein the diamond nucleation layer is such that said Raman signal further exhibits one or both of the following characteristics: (i) an sp2 carbon peak at 1550 cm-1 having a height which is no more than 20% of a height of the sp3 carbon peak at 1332 cm-1 after background subtraction when using a Raman excitation source at 633 nm; and (ii) the sp3 carbon peak at 1332 cm-1 is no less than 10% of local background intensity in a Raman spectrum using a Raman excitation source at 785 nm, and wherein an average nucleation density at a nucleation surface of the diamond nucleation layer is no less than 1 x 108 cm-2and no more than 1 x 1012 cm-2. |
