基于量子点测量LED芯片表面温度的实验研究

Experimental Study on LED Chip Surface Temperature Via the Quantum Dot

本文围绕CdSe/ZnS量子点发光光谱与温度的依赖关系,对LED芯片表面温度进行实验研究。CdSe/ZnS量子点作为温度传感器对GaN LED芯片表面温度进行测量,量子点的掺入导致光谱中引入量子点发射谱,测得不同温度下的光致发光谱,通过红外热像仪对LED芯片表面温度进行定标,就可以获得LED芯片表面温度和量子点光谱峰值波长的曲线,最后利用该方法测得LED芯片在不同电流下和不同通电时间的表面温度。实验结果表明在25~85℃温度范围内,CdSe/ZnS量子点温度灵敏度为0.11 nm/℃,测温精度为±3℃。

This work focus on the monitor of the LED chip surface temperature via the CdSe/ZnS quantum dot temperature-dependent photoluminescence spectra. The CdSe/ZnS quantum dots （QDs） were used as an on-chip temperature sensor to measure the surface temperature of GaN LED chip. Doped quantum dots caused spectral changes, and photoluminescence spectra were measured at different temperatures. With the calibration by using an infrared thermal image camera, the temperature-dependent photoluminescence spectra were obtained. The surface temperature of GaN LED chip was measured at different current and working time. Experimental results show that the temperature sensitivity characterized by the photoluminescence peak wavelength of CdSe/ZnS QDs was found to be 0.11 nm/℃ at the range of 2.5-85℃, and the precision was determined to be ±3℃.