Investigation of Forward Voltage Uniformity in Monolithic Light-Emitting Diode Arrays

Author

Zhao Jun Liu ; Wing Cheung Chong ; Ka Ming Wong ; Chi Wing Keung ; Kei May Lau

Author_Institution

Dept. of Electron. & Comput. Eng., Hong Kong Univ. of Sci. & Technol., Kowloon, China

Volume

25

Issue

13

fYear

2013

fDate

1-Jul-13

Firstpage

1290

Lastpage

1293

Abstract

This letter reports the design and fabrication of optimized electrode structures for matrix addressable monolithic light-emitting diode arrays. The variation of forward voltages of LED pixels in the same row are greatly reduced from 2.62 V (81.9%) to 0.02 V (0.6%) in an 8×8 LED array. The LED arrays are designed with 8×8 square pixels, 500×500 μm² with a 50-μm wide gap in between. A 24×24 large-scale blue LED panel is demonstrated with 0.06 V (1.8%) forward voltage variation by integrating nine LED array modules on a 2.2-cm diagonal silicon-based substrate. With a similar concept, a 30×30 green LED micro-display with scaled pixel pitch shows excellent display uniformity.

Keywords

LED displays; integrated optoelectronics; microdisplays; optical arrays; optical design techniques; optical fabrication; LED array modules; LED pixels; Si; diagonal silicon-based substrate; display uniformity; forward voltage uniformity; green LED microdisplay; large-scale blue LED panel; matrix addressable monolithic light-emitting diode arrays; optimized electrode structures; scaled pixel pitch; size 2.2 cm; square pixels; voltage 2.62 V to 0.02 V; Gallium compounds; arrays; flip-chip devices; light-emitting diodes;

fLanguage

English

Journal_Title

Photonics Technology Letters, IEEE

Publisher

ieee

ISSN

1041-1135

Type

jour

DOI

10.1109/LPT.2013.2263223

Filename

6516916