Fig. 1. (Color online) The XRD rocking curves (XRC) of (002) (circles) and (102) (squares) planes for (a) as-sputtered and (b) HTA AlN samples.

Fig. 2. Cross-sectional weak-beam dark-field (WBDF) TEM images of HTA AlN taken under diffraction conditions of (a) g = ( ) and (b) g = ( ). For g = ( )/( ), the screw-type/edge-type dislocation is visible. (c) Cross-sectional high-resolution HAADF-STEM along the [ ] direction by focusing on the interfacial region.

Fig. 3. (Color online) Atomic force microscopy images of (a) as-sputtered AlN, (b) HTA AlN as well as (c) MOCVD regrown AlN. (d) The SEM image of MOCVD regrown AlN on HTA AlN template. The height bar is 20 nm.

Fig. 4. (Color online) (a) Positions of five measured XRC points on 4-inch as-sputtered AlN and MOCVD regrown AlN wafers, and the results are shown in Table 1. (b) Optical microscopy image of the edge region in MOCVD regrown AlN wafer on 4-inch HTA AlN template. The images of surface cracks on (c) HTA AlN and (d) AlN/NPSS templates are measured by Candela.

Table 1. Five points XRC FWHMs and θ–ω calculated strains of 4-inch post-HTA AlN and MOCVD regrown AlN wafers.