Electrical properties and microstructure of ternary Ge∕Ti∕Al ohmic contacts to p-type 4H–SiC
Electrical properties and microstructure of ternary Ge∕Ti∕Al ohmic contacts to p-type 4H–SiC
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DOI：
10.1063/1.1797546
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发表时间：
2004-10
影响因子：
3.2
通讯作者：
S. Tsukimoto;T. Sakai;M. Murakami
中科院分区：
文献类型：
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作者：
S. Tsukimoto;T. Sakai;M. Murakami
高功率的碳化硅器件需要欧姆接触材料，而欧姆接触材料是在低于800°C的温度下热处理而成的。太棒了。在传统的二元Ti/Al接触中加入少量Ge，可使欧姆接触的形成温度降低约500°C，这种三元接触在600℃的温度下热处理后的比接触电阻约为1×10−4Ωcm~2。本文通过电流-电压测量和电子显微镜观察，分别研究了Ge/Ti/Al接触的电学性质和微观结构。观察到Ti3SiC2化合物层(先前观察到的Ti3SiC2化合物层在高于1000°C的温度下，在Ti/Al欧姆接触的金属/碳化硅界面上)外延生长。
The high-power SiC devices require ohmic contact materials, which are prepared by annealing at temperatures lower than 800°C. Recently, we demonstrated in our previous paper [J. Appl. Phys. 95, 2187 (2004)] that an addition of a small amount of Ge to the conventional binary Ti∕Al contacts reduced the ohmic contact formation temperature by about 500°C, and this ternary contacts yielded a specific contact resistance of approximately 1×10−4Ωcm2 after annealing at a temperature as low as 600°C. In this paper, the electrical properties and the microstructures of the Ge∕Ti∕Al contacts (where a slash “/” indicates the deposition sequence) were investigated by current-voltage measurements and transmission electron microscopy observations, respectively, in order to understand the ohmic contact formation mechanism. Ti3SiC2 compound layers (which were previously observed at the metal/SiC interface in the Ti∕Al ohmic contacts after annealing at temperatures higher than 1000°C) were observed to grow epitaxially on the...