Study of Voltage-Temperature Coefficient of High Power Light-Emitting Diodes
Voltage-temperature coefficient (S) is the key parameter for measuring the light-emitting diode (LED)’s junction temperature.Common method for determining junction temperature by the S is under low current condition from 0.1mA to 5mA.However,there are limited studies of parameter S under high current.The measurement of S dependent on forward current (IF) can be adopted for the real-time monitoring of junction temperature.In theoretical analysis,we find a relationship between S and IF for p-n junction.Experimentally,we investigate the S under IF ranging from 0.1mA to 350mA for three 1-watt LEDs and from 0.1mA to 1000mA for three 3-watt LEDs.The samples are with different junction materials,die sizes,chip structures,substrate materials and bonding technologies.The analysis of the experiment result indicates that the relationship is logarithmic in low current region,and it becomes near linear in high current region.We also give an explanation for the deviation of the curves when current is higher than 350mA.Comparative study of six LED samples shows that the chip structures and bonding technologies play a major role on the S-IF relationship.
Ning Li Peng Jin
School of Environment and Energy,Peking University Shenzhen Graduate School Shenzhen university town,Xili,Shenzhen,China
国内会议
北京
英文
40-44
2013-11-10（万方平台首次上网日期，不代表论文的发表时间）