Sustained high external quantum efficiency in ultrasmall blue III–nitride micro-LEDs. (1st February 2017)

• Record Type: Journal Article
• Authors: Hwang, David; Mughal, Asad; Pynn, Christopher D.; Nakamura, Shuji; DenBaars, Steven P.
• Is Part Of: Applied physics express. Volume 10:Number 3(2017)
• Publication Date: 2017-02-01
• Subjects: Physics -- Periodicals; Technology -- Periodicals; 621.05
• DOI: 10.7567/APEX.10.032101
• Languages: English
• ISSNs: 1882-0778

Abstract

Abstract: Ultrasmall blue InGaN micro-light-emitting diodes (µLEDs) with areas from 10 −4 to 0.01 mm 2 were fabricated to study their optical and electrical properties. The peak external quantum efficiencies (EQEs) of the smallest and largest µLEDs were 40.2 and 48.6%, respectively. The difference in EQE was from nonradiative recombination originating from etching damage. This decrease is less severe than that in red AlInGaP LEDs. The efficiency droop at 900 A/cm 2 of the smallest µLED was 45.7%, compared with 56.0% for the largest, and was lower because of improved current spreading. These results show that ultrasmall µLEDs may be fabricated without a significant loss in optical or electrical performance.