A Novel THz Differential Spectral Clustering Recognition Method Based on t-SNE

Table 1

The sample information of CMC and silicon.

The sample name	Specification	Description
Aluminum oxide (Al2O3) sheet with defects	Length × width × thickness (mm): 101.0 × 101.0 × 3.0 mm; Bulk density ≥ 3.65 g/cm^3; Surface roughness Ra ≥ 0.5 μm; Principal component content ≥ 95%	Gray-white, defects are internal irregularities cracks
Beryllium oxide (BeO) sheet with defects	Length × width × thickness (mm): 50.8 × 50.8 × 1.5; Bulk density ≥ 2.85 g/cm^3; Surface roughness Ra ≥ 0.1 μm; Principal component content ≥ 99%	Pure white, highly toxic powder, the defect is the shape of the regular set of holes 4; Outside diameter: 4.2–5.9 mm; Inner diameter: 2.6–4.2 mm; Hole depth: 0.8 mm
Beryllium oxide (BeO) sheet with zero defects	Length × width × thickness (mm): 50.8 × 50.8 × 1.5; Bulk density ≥ 2.85 g/cm^3; Surface roughness Ra ≥ 0.1 μm; Principal component content ≥ 99%	Pure white, highly toxic powder, zero defects
Monocrystalline silicon with zero defects	Thickness :   450 ± 10 μm; Diameter :  76.3 ± 0.2 mm; N dopant (phosphorus); Crystal orientation:<111>	Crystal growth: CZ resistivity: 14–45 Ωcm zero defects