High-Frequency Modulation of GaAs/AlGaAs LEDs Using Ga-Doped ZnO Current Spreading Layers

Author

Shang-Fu Chen ; He-Long Syu ; Chi-Chen Huang ; Yueh-Lin Lee ; Chong-Long Ho ; Meng-Chyi Wu

Author_Institution

Inst. of Electron. Eng., Nat. Tsing Hua Univ., Hsinchu, Taiwan

Volume

35

Issue

1

fYear

2014

fDate

Jan. 2014

Firstpage

36

Lastpage

38

Abstract

In this letter, we report the high-frequency modulation of GaAs/AlGaAs near-infrared (NIR) light-emitting diodes (LEDs) with gallium-doped zinc oxide (GZO) prepared by atomic layer deposition as a current spreading layer. This report analyzes the effects of aperture area of the NIR LEDs on minority carrier lifetime and further investigates the required injection current to achieve the 3-dB frequency bandwidth of 100 MHz. At the same injection current density, the LEDs with different aperture areas always exhibit the same minority carrier lifetime, which is inversely proportional to the square root of current density. It means that the GZO layer plays a good current spreading in the lateral direction from the ohmic contact of NIR LEDs, which shows the lower contact resistance and lower forward voltage.

Keywords

III-V semiconductors; aluminium alloys; atomic layer deposition; carrier lifetime; contact resistance; current density; frequency modulation; gallium arsenide; light emitting diodes; minority carriers; ohmic contacts; zinc compounds; GaAs-AlGaAs; NIR LED; atomic layer deposition; bandwidth 100 MHz; contact resistance; current spreading layer; gallium-doped zinc oxide current spreading layers; high-frequency modulation; injection current density; minority carrier lifetime; near-infrared light-emitting diodes; ohmic contact; Apertures; Bandwidth; Capacitance; Charge carrier lifetime; Current density; Light emitting diodes; Resistance; 3-dB modulation bandwidth; GaAs; LEDs; atomic layer deposition (ALD); gallium-doped ZnO (GZO); minority carrier lifetime;

fLanguage

English

Journal_Title

Electron Device Letters, IEEE

Publisher

ieee

ISSN

0741-3106

Type

jour

DOI

10.1109/LED.2013.2291566

Filename

6680614