Influence of the Metallization Composition and Annealing Process Parameters on the Resistance of Ohmic Contacts to n-type 6H-SiC

• Published in: Semiconductors (Woodbury, N.Y.) Vol. 53; no. 15; pp. 2012 - 2015
• Main Authors: Egorkin, V. I., Zemlyakov, V. E., Nezhentsev, A. V., Gudkov, V. A., Garmash, V. I.
• Format: Journal Article
• Language: English
• Published: Moscow Pleiades Publishing 01.12.2019; Springer Nature B.V
• Subjects: Alloying; Composition; Contact resistance; Crystallography; Doping; Electronics; Intermetallic compounds; Low resistance; Magnetic Materials; Magnetism; Metallizing; Nickel; Nitrogen ions; Physics; Physics and Astronomy; Process parameters; Resistance factors; Silicon carbide; Technological Processes and Routes; Titanium aluminides; Titanium base alloys; ohmic contact; silicon carbide; ion implantation
• ISSN: 1063-7826; 1090-6479
• DOI: 10.1134/S1063782619150053

For silicon carbide, the problem of obtaining low-resistance ohmic contacts with improved service characteristics remains topical despite a significant body of experimental data. The influence exerted by the composition of Ni and TiAl metallization, alloying parameters, additional doping of the contact layer of silicon carbide (SiC) with N + nitrogen ions, and the crystallographic Si- or C-face on the resistance of ohmic contacts  to n -6 H -SiC  is examined.  It is  found  that the greatest influence on how ohmic contacts to n -6 H -SiC are formed is exerted by the alloying process resulting in a decrease in the contact resistance by approximately six times. The process of additional doping with N + also reduces the contact resistance by nearly a factor of four. It is found that low-resistance contacts can be obtained on both faces with approximately the same low resistance. TiAl metallization is optimal for the C-face, and Ni metallization, for the Si-face. This choice of metallization makes it possible to obtain ohmic contacts on both polar faces with approximately the same resistances on the order of 2.5 × 10 –4 Ω cm 2 .