Cadmium Telluride (CdTe)

Direct-bandgap II-VI semiconductor that dominates thin-film photovoltaics.

Core Principles & Analysis

• Its direct bandgap of about 1.5 eV sits near the optimum for the solar spectrum, so a film only a few micrometres thick absorbs most usable sunlight.
• CdTe is the second most deployed solar cell technology after silicon, with record research cell efficiencies above 22%.
• Alloyed with zinc as CdZnTe, it forms room-temperature X-ray and gamma-ray detectors used in medical imaging and security scanners.

Specifications & Metrics

• DENSITY: 5.85 g/cm³
• YIELD STRENGTH: N/A (brittle)
• HARDNESS: 50 HK