High-Brightness InGaN–GaN Power Flip-Chip LEDs

Sum DJ

Shoou-Jinn Chang, Member, IEEE, W. S. Chen, S. C. Shei, C. T. Kuo, T. K. Ko, C. F. Shen, J. M. Tsai,Wei-Chi Lai, Jinn-Kong Sheu, and A. J. Lin

JOURNAL OF LIGHTWAVE TECHNOLOGY, VOL. 27, NO. 12, JUNE 15, 2009

Outline

• Introduction

• Experiment

• Results and discussion

• Conclusion

• References

Introduction

• In this work, we report the fabrication of

InGaN–GaN power flip-chip (FC) LEDs using grinding to rough the backside surface of sapphire substrate.

MQW five-period In0.23Ga0.77N(3nm)/GaN(7nm) @770ºC

Sapphire (2-inch)

GaN nucleation layer (50nm) @ 550ºC

n+-GaN(3µm) @ 1050ºC

Experiment

EBL p-Al0.15Ga0.85N(50nm) @1050ºC

SPS five-period In0.23Ga0.77N (5Å)/GaN(5Å) @1050ºCp+-GaN(0.25µm) @ 1050ºC

ITO(15nm)

Ni(1nm)

Ag(200nm)

Ti/Al/Ti/Au

chip size ： 1mm × 1mm

Results and discussion

Results and discussion

Results and discussion

Results and discussion

Results and discussion

455nm

Results and discussion

LED-I ： 366.5mWLED- II ： 271.8mWLED-III ：185.1mW@700mA

700mA

Results and discussion

0.35A

Results and discussion

Conclusion

• We can achieve a 200 times larger peak-to-valley distance on the backside sapphire substrate by conventional lapping/polishing.

• It was also found that we can simultaneously enhance output power and improve device reliability by roughening sapphire backside surface of the power FC LEDs.

References

• Shoou-Jinn Chang, Member, IEEE, W. S. Chen, S. C. Shei, C. T. Kuo, T. K. Ko, C. F. Shen, J. M. Tsai,Wei-Chi Lai, Jinn-Kong Sheu, and A. J. Lin“High-Brightness InGaN–GaN Power Flip-Chip LEDs,” J. Lightwave Technol. VOL. 27, NO. 12, JUNE 15, 2009

• Thanks for your attention !