Ni-Based Ohmic Contacts to n-Type 4H-SiC: The Formation Mechanism and Thermal Stability

Table 2

Properties of Ni and Ni₂Si contacts to n-type (~2 × 10¹⁷ cm⁻³) 4H-SiC bulk wafers versus annealing temperature.

Annealing temperature	n-SiC/Ni			n-SiC/Ni2Si
	(×10^−4 Ω cm^2)	(nm)	(nm)	(×10^−4 Ω cm^2)	(nm)	(nm)
As-deposited	I-V: nonlinear	~3	~86	I-V: nonlinear	~3	~110
600°C/15 min	I-V: nonlinear	~40	~186	I-V: nonlinear	~4	~100
1050°C/3 min	4 ± 2	~58	~225	4.5 ± 1	~12	~108

Peak-to-valley height () on the 25 µm surface scan length and thickness () of metallization measured by TENCOR α-Step Profiler.