Table 1 The TDDs, refractive index, and Raman E₂(h) peak positions of AlN samples

Total TDDs (cm^− 2)

3.48 × 10⁹

8.27 × 10⁸

6.15 × 10⁸

5.86 × 10⁸

4.24 × 10⁸

Refractive index at 633 nm

2.0190

2.0249

2.0312

2.0436

2.0559

Refractive index at 365 nm

2.1001

2.1076

2.1131

2.1264

2.1405

Refractive index at 280 nm

2.2102

2.2175

2.2222

2.2366

2.2508

Position of E₂(h) (cm⁻¹)

657.56

661.12

662.88

663.20

663.49