| 摘要 |
A III-V nitride, e.g., GaN, substrate including a (0001) surface offcut from the <0001> direction predominately toward the <1010> direction or the <1120> direction, at the offcut angle in a range that is from about 0.2 to about 10 degrees (FIGURE 9). The surface has a RMS roughness measured by 50 x 50 mircometers squared AFM scan that is less than 1 nm, and a dislocation density that is less than 3E6 cm-2. The substrate can be formed by offcut slicing of a corresponding boule or wafer blank, by offcut lapping or growth of the substrate body on a corresponding vicinal heteroepitaxial substrate, e.g., offcut sapphire. The substrate is usefully employed for homoepitaxial deposition in the fabrication III-V nitride-based microelectronic and optoelectronic devices. |
