Electrical and thermal stability of Ag ohmic contacts for GaN-based flip-chip light-emitting diodes by using an AgAl alloy capping layer

被引：14

作者：

Hwang, Yoon Tae

Hong, Hyun-Gi

Seong, Tae-Yeon ^{[1
]}

Leem, D.-S.

Lee, T.

Kim, K.-K.

Song, J. O.

机构：

[1] Korea Univ, Dept Mat Sci & Engn, Seoul 136713, South Korea

[2] Gwangju Inst Sci & Technol, Dept Mat Sci & Engn, Kwangju 500712, South Korea

[3] Seoul Natl Univ, Sch Mat Sci & Engn, Seoul 151742, South Korea

[4] Samsung Adv Inst Technol, Photon Program Team, Suwon 440600, South Korea

来源：

MATERIALS SCIENCE IN SEMICONDUCTOR PROCESSING | 2007年 / 10卷 / 01期

关键词：

GaN-based flip-chip LEDs; Ag reflector; thermal stability; AgAl capping layer; ohmic contacts; P-TYPE GAN; LOW-RESISTANCE; MECHANISMS;

D O I：

10.1016/j.mssp.2007.01.001

中图分类号：

TM [电工技术]; TN [电子技术、通信技术];

学科分类号：

0808 ; 0809 ;

摘要：

We have investigated Ag(200 nm)/AgAl(100 nm) ohmic contacts to p-type GaN for near-UV (405 nm) flip-chip light-emitting diodes (LEDs). It is shown that the use of an AgAl alloy capping layer (with 8 at% Al) results in better electrical and optical properties as compared to single Ag contacts when annealed at 430 degrees C. For example, Ag/AgAl (8 at% Al) contacts give specific contact resistance of 4.6 x 10(-4) Omega cm(2) and reflectance of 90% at a wavelength of 405 nm. However, use of an AgAl (with 50 at% Al) layer is not effective. LEDs fabricated with the Ag/AgAl (8 at% Al) reflectors produce higher light output as compared with the ones with single Ag reflectors. Ohmic mechanisms of the Ag/AgAl (8 at% Al) contacts are described and discussed. (C) 2007 Elsevier Ltd. All rights reserved.

引用

页码：14 / 18

页数：5

共 16 条

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[Anonymous], 2003, HDB CHEM PHYS

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