Lead Sulfide Quantum Dots as the Semiconductor Layer in Thin-Film Phototransistors for Infrared Thermal Image Sensing

This paper utilizes lead sulfide quantum dots, known for their high absorption coefficients, ease of solution processing, and high stability in air, as the semiconductor layer in thin-film phototransistors. These are combined with the most mature glass panel processing technology to create an infrared sensing device characterized by simple manufacturing processes, low production costs, small sensing areas, and large-area sensing capabilities. The novel lead sulfide quantum dot infrared sensing device proposed here exhibits remarkable performance at room temperature and under uncooled operation. It demonstrates a temperature sensitivity above 300 °C for radiation temperature measurement, a fast total response time of 69 μs, and performance metrics such as noise of 1.9 × 10⁻¹² A/Hz^1/2, a maximum responsivity of 103 A W⁻¹, and a maximum detectivity of 2.04 × 10¹³ Jones. Therefore, the experimental results obtained here are significant for the research and design of future advanced quantum dot-based thermal imaging sensing applications.