Silver Telluride Quantum Dots on Silicon Near-Infrared Photodetectors

Ag2Te quantum dots (QDs) are narrow-bandgap, heavy metal-free QDs with significant potential for near-infrared detection. In this study, we fabricated a silicon-based Ag2Te QD near-infrared photodetector to assess its feasibility for large-scale silicon-based integration. The Ag2Te QDs synthesized by hot injection method, have an average size of 5 nm and a bandgap of 0.73 eV. These narrow bandgap Ag2Te QDs were successfully deposited onto silicon wafers following ligand exchange. At room temperature, the QD photodetector demonstrated a high responsivity of 150 A/W and a specific detectivity of 4.8 × 1012 Jones under 1050 nm illumination. Additionally, we investigated the effects of electrode positioning and QD film thickness on the device performances, establishing a foundation for the low-cost, large-scale integration of the narrow-bandgap QD materials with the silicon platform.