Low resistivity Hf/Al/Ni/Au Ohmic Contact Scheme to n-Type GaN
نویسندگان
چکیده
The electrical and structural properties of Hf/Al/Ni/Au (20/100/25/50 nm) ohmic contact to n-GaN are reported in this study. Specific contact resistivities of Hf/Al/Ni/Au based contacts have been investigated as a function of annealing temperature and achieve the lowest value of 1.09×10 Ω·cm after annealing at 650 C in vacuum. A detailed mechanism of ohmic contact formation is discussed. By using different chemical analyses, it is anticipated that the formation of Hf-Al-N alloy might be responsible to form low temperature ohmic contacts for the Hf-based scheme to n-GaN. Keywords—Gallium nitride, ohmic contact, Hafnium
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