Acta Phys. -Chim. Sin. ›› 2016, Vol. 32 ›› Issue (4): 1029-1035.doi: 10.3866/PKU.WHXB201601292

• ARTICLE • Previous Articles     Next Articles

Contact Resistance Effects in Carbon Nanotube Thin Film Transistors

Ji-Ye XIA1,Guo-Dong DONG1,Bo-Yuan TIAN1,Qiu-Ping YAN1,Jie HAN2,Song QIU2,Qing-Wen LI2,Xue-Lei LIANG1,*(),Lian-Mao PENG1   

  1. 1 Key Laboratory for the Physics and Chemistry of Nanodevices, Department of Electronics, Peking University, Beijing 100871, P. R. China
    2 Suzhou Institute of Nano-Tech and Nano-bionics, Chinese Academy of Sciences, Suzhou 215123, Jiangsu Province, P. R. China
  • Received:2015-12-11 Published:2016-04-07
  • Contact: Xue-Lei LIANG E-mail:liangxl@pku.edu.cn
  • Supported by:
    the Research Project of Chinese National Natural Science Foundation of China(61321001);Beijing Municipal Science & Technology Commission, China(Z141100003814006);Research Project of the Ministry of Education of China(113003A)

Abstract:

The contact resistance effect in the network type carbon nanotube thin film transistors (CNT-TFTs) is studied by using different contact metals. It is shown that palladium (Pd) can form an ohmic type contact with the carbon nanotube thin film, and gold (Au) forms an almost ohmic contact. On-state current and carrier mobility in the devices of these two contacts are high. In contrast, both titanium (Ti) and aluminum (Al) form Schottkytype contacts with the carbon nanotube thin film. The barrier height and the contact resistance of the Al contact are higher than those of the Ti contact. Therefore, the on-state current and carrier mobility are relatively low in the corresponding devices of these two types of contacts. These results indicate that the performance of CNTTFTs can be tuned by the contact metal, which is important for the commercialization of CNT-TFTs.

Key words: Carbon nanotube, Thin film transistor, Contact resistance, Ohmic contact, Schottky barrier