Formation of the intermediate semiconductor larger for the Ohmic contact to silicon carbide using Germanium implantation
Guo Hui(郭辉)a)†, Wang Yue-Hu(王悦湖)a), Zhang Yu-Ming(张玉明)a), Qiao Da-Yong(乔大勇)b), and Zhang Yi-Men(张义门)a)
a Microelectronics School, Xidian University, Xi'an 710071, China and Key Lab of Wide Band-Gap Semiconductor Materials and Devices, Xi'an 710071, China; b Micro and Nano Electromechanical Systems Laboratory, Northwestern Polytechnical University, Xi'an 710072, China
Abstract By formation of an intermediate semiconductor layer (ISL) with a narrow band gap at the metallic contact/SiC interface, this paper realises a new method to fabricate the low-resistance Ohmic contacts for SiC. An array of transfer length method (TLM) test patterns is formed on N-wells created by P+ ion implantation into Si-faced p-type 4H-SiC epilayer. The ISL of nickel-metal Ohmic contacts to n-type 4H-SiC could be formed by using Germanium ion implantation into SiC. The specific contact resistance $\rho_{\rm c}$ as low as 4.23× 10-5 $\Omega\cdot$cm2 is achieved after annealing in N2 at 800 °C for 3 min, which is much lower than that (>900 °C) in the typical SiC metallisation process. The sheet resistance Rsh of the implanted layers is 1.5 k$\Omega$/$\Box$. The technique for converting photoresist into nanocrystalline graphite is used to protect the SiC surface in the annealing after Ge+ ion implantations.
Received: 13 January 2009
Revised: 07 April 2009
Accepted manuscript online:
(Cold working, work hardening; annealing, post-deformation annealing, quenching, tempering recovery, and crystallization)
Fund: Project supported by the National
Natural Science Foundation of China (Grant No J54508250120) and
Xi'an Applied Materials Innovation
Fund (Grant No XA-AM-200704).
Cite this article:
Guo Hui(郭辉), Wang Yue-Hu(王悦湖), Zhang Yu-Ming(张玉明), Qiao Da-Yong(乔大勇), and Zhang Yi-Men(张义门) Formation of the intermediate semiconductor larger for the Ohmic contact to silicon carbide using Germanium implantation 2009 Chin. Phys. B 18 4470
Altmetric calculates a score based on the online attention an article receives. Each coloured thread in the circle represents a different type of online attention. The number in the centre is the Altmetric score. Social media and mainstream news media are the main sources that calculate the score. Reference managers such as Mendeley are also tracked but do not contribute to the score. Older articles often score higher because they have had more time to get noticed. To account for this, Altmetric has included the context data for other articles of a similar age.