Title :
In-Situ Measurement of Junction Temperature and Light Intensity of Light Emitting Diodes With an Internal Sensor Unit
Author :
Jiaming Li ; Yugang Zhou ; Yundong Qi ; Zhenlin Miao ; Yanming Wang ; Xiangqian Xiu ; Bin Liu ; Rong Zhang ; Youdou Zheng
Author_Institution :
Jiangsu Provincial Key Lab. of Adv. Photonic & Electron. Mater., Nanjing Univ., Nanjing, China
Abstract :
This study designed and tested an innovative light-emitting diode (LED) chip with a built-in sensor. Two electrically isolated units, the LED (for light emission) and the sensor (for monitoring junction temperature and light intensity), were integrated on a single chip. The sensor unit determines the junction temperature by measuring the forward voltage; the light output power of the LED unit can be precisely extrapolated with a polynomial function based on the photocurrent and junction temperature. This novel structure enables the in-situ real-time monitoring of the LED junction temperature and light output power, which allows a highly detailed and/or in-field LED reliability analysis and provides valuable feedback information for smart LED lighting systems.
Keywords :
electric sensing devices; light emitting diodes; lighting; polynomials; semiconductor device reliability; temperature measurement; voltage measurement; LED chip; LED reliability analysis; built-in sensor; electrically isolated units; forward voltage measurement; in-situ measurement; in-situ real-time monitoring; internal sensor unit; junction temperature; light emitting diodes; light intensity; photocurrent temperature; polynomial function; smart LED lighting systems; Junctions; Light emitting diodes; Optical variables measurement; Photoconductivity; Reliability; Temperature measurement; Temperature sensors; Built-in sensor; junction temperature; light emitting diodes (LEDs); light output power; photocurrent;
Journal_Title :
Electron Device Letters, IEEE
DOI :
10.1109/LED.2015.2471801
