Title :
High thermal stability of high-power phosphor based white-light-emitting diodes employing Ce:YAG-doped glass
Author :
Tsai, Chun-Chin ; Chung, Cheng-Hsun ; Wang, Jimmy ; Cheng, Wei-Chih ; Chen, Ming-Hung ; Liou, Jyun-Sian ; Chang, Jin-Kai ; Hsu, Yi-Cheng ; Hung, Shang-Chao ; Lee, Chao-Wei ; Hu, Hung-Lieh ; Huang, Sheng-Bang ; Kuang, Jao-Hwa ; Cheng, Wood-Hi
Author_Institution :
Dept. of Photonics, Nat. Sun Yat-sen Univ., Kaohsiung, Taiwan
Abstract :
High thermal stability of high-power phosphor-converted white-light-emitting diodes (PC-WLEDs) incorporating a Ce:YAG-doped glass as the phosphor layer is demonstrated. An exploring study of lumen loss, chromaticity shift, and transmittance loss of high-power PC-WLEDs with Ce:YAG-doped glass and Ce:YAG-doped silicone under thermal aging at 150°C for 500 hours was performed and compared. The results showed that the high-power PC-WLEDs with 6 wt% of Ce:YAG-doped glass exhibited 60% less lumen loss, 50% lower chromaticity (CIE) shift, and 20% smaller transmittance loss than with the Ce:YAG-doped silicone. This clearly indicates that the Ce:YAG-doped glass exhibits higher thermal stability than the Ce:YAG-doped silicone after thermal aging. A better thermal stability of glass phosphor layer may be beneficial to the many applications where the LEDs with high-power and high reliability are demanded.
Keywords :
cerium; glass; light emitting diodes; phosphors; thermal stability; YAG:Ce; chromaticity shift; high thermal stability; high-power phosphor; lumen loss; phosphor layer; thermal aging; transmittance loss; white-light-emitting diodes; Aging; Degradation; Glass; Light emitting diodes; Phosphors; Propagation losses; Semiconductor device packaging; Semiconductor diodes; Semiconductor materials; Thermal stability;
Conference_Titel :
Electronic Components and Technology Conference (ECTC), 2010 Proceedings 60th
Conference_Location :
Las Vegas, NV
Print_ISBN :
978-1-4244-6410-4
Electronic_ISBN :
0569-5503
DOI :
10.1109/ECTC.2010.5490776
