NiGe‐based ohmic contacts to n‐type GaAs. II. Effects of Au addition
NiGe‐based ohmic contacts to n‐type GaAs. II. Effects of Au addition
复制标题
NiGe 基欧姆接触对 n 型 GaAs II 的影响。
DOI：
10.1063/1.356226
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发表时间：
1994
影响因子：
3.2
通讯作者：
M. Murakami
中科院分区：
文献类型：
--
作者：
Hirotaka Kawata;T. Oku;A. Otsuki;M. Murakami
我们一直在努力通过向NiGe接触添加少量的第三元素来改善NiGe欧姆接触的电性能，而不劣化热稳定性和表面光滑度。在本研究中，选择Au作为第三元素，并通过制备具有不同厚度比的Ni、Ge和Au层的各种接触来确定产生热稳定、低电阻欧姆接触的最佳条件。通过在n型GaAs衬底上依次沉积Ni（40 nm）、Au（5 nm）和Ge（100 nm）并在450 °C下退火5 s来制备最佳欧姆接触。该接触提供了约0.2 Ω mm的接触电阻，其低于NiGe（In）接触的接触电阻。本发明的触头在触头形成后具有光滑的表面，并且在400 °C的等温退火期间显示出优异的热稳定性。用高分辨电子显微镜观察了GaAs/金属界面的横截面，结果表明，GaAs/金属界面是均匀的。
Our efforts have been continued to improve the electrical properties of NiGe ohmic contacts by adding a small amount of a third element to the NiGe contacts without deteriorating thermal stability and surface smoothness. In the present study, Au was chosen as the third element, and the optimum conditions to produce thermally stable, low resistance ohmic contacts were determined by preparing a variety of contacts with different thickness ratios of the Ni, Ge, and Au layers. The best ohmic contact was prepared by depositing sequentially Ni (40 nm), Au (5 nm), and Ge (100 nm) onto the n‐type GaAs substrate, and annealing at 450 °C for 5 s. This contact provided the contact resistance of about 0.2 Ω mm, which is lower than that of the NiGe(In) contacts. The present contact had smooth surface after contact formation and showed excellent thermal stability during isothermal annealing at 400 °C. The cross‐sectional observation using high‐resolution electron microscopy indicated that the GaAs/metal interface was u...