Characterization of Pd/Ni/Au ohmic contacts on p-GaN

被引:33
作者
Cho, HK [1 ]
Hossain, T [1 ]
Bae, JW [1 ]
Adesida, I [1 ]
机构
[1] Univ Illinois, Dept Elect & Comp Engn, Micro & Nanotechnol Lab, Urbana, IL 61801 USA
关键词
GaN; contact resistance; Pd; Ni; intermetallic compounds;
D O I
10.1016/j.sse.2005.01.020
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
A low-resistance ohmic contact to Mg-doped p-type GaN grown by metal-organic chemical vapor deposition (MOCVD) with a carrier concentration of 2 x 10(17) cm(-3) using Pd/Ni/Au metallization was formed. An anneal at 500 degrees C for 1 min in a flowing N-2 ambient produced an excellent ohmic contact with a specific contact resistivity as low as 2.4 x 10(-5) K-2 Cm-2. X-ray photoelectron spectroscopy (XPS) and Auger electron spectroscopy (AES) depth profiles of Pd/Ni/Au contacts annealed at 500 degrees C demonstrated a strong correlation between Ni and Pd interdiffusion toward the GaN surface and a reduction in specific contact resistance. The low contact resistance is attributed to the reduction of the native oxide by Ni diffusion along with the formation of Pd and Ni related-gallide phases at the p-GaN surface region. (c) 2005 Elsevier Ltd. All rights reserved.
引用
收藏
页码:774 / 778
页数:5
相关论文
共 22 条
[21]  
Vassilevski KV, 1996, MRS INTERNET J N S R, V1, pU298
[22]   CORE-LEVEL BINDING-ENERGY SHIFTS IN METALS [J].
WILLIAMS, AR ;
LANG, ND .
PHYSICAL REVIEW LETTERS, 1978, 40 (14) :954-957