Metal Contact on P-Type 4H-SiC With Low Specific Contact Resistance and Micrometer-Scale Contact Area

In this study, metal contact on p-type SiC with low specific contact resistance was developed using TiAl. Using fine-tuned TiAl deposition and annealing conditions on p-type SiC, the Ti–Si–C interfacial layer grown on high temperature ion implanted
$\text{P}^{+}$
SiC is nonuniform and exhibits nonohmic behavior when the contact area becomes smaller than
$10\,\,\mu \text{m}\,\,\times 10\,\,\mu \text{m}$
. This area dependence can be improved through low-energy, room-temperature (LERT) ion implantation and Ar plasma treatment prior to metal deposition. Ar plasma treatment results in a uniform Al–Si–C interfacial layer. Moreover, the defects produced by LERT ion implantation promote trap-assisted tunneling. Through the aforementioned methods, metal contact on p-type SiC with a record-low specific contact resistance of
$3\times 10^{-{5}}\,\,\Omega $
cm2 at record-small contact area of
$1.5\,\,\mu \text{m}\,\,\times 1.5\,\,\mu \text{m}$
was obtained in this study.