Planar temperature sensing using heavy-metal-free quantum dots with micrometer resolution

This work describes a micrometer resolution and plane-array temperature-sensing method using the photoluminescence (PL) of ZnCuInS/ZnSe/ZnS quantum dots (QDs). Heavy-metal-free QDs were directly deposited on a printed circuit board to analyze the surface temperature of the devices on the board. An optical fiber monochromator and a high-powered microscope were employed to fabricate a system which could collect temperature-dependent QD emissions from the micrometer area for the temperature measurements. This system realizes the imaging of the surface temperature distribution in the planar micrometer area. Temperature sensitivity of the PL intensity reached 0.66% °C−1, and the relative error was less than 2%.