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

Figure 12

(a) Calculated ohmic contact resistance () as a function of the doping concentration () of 4H-n-SiC for various barrier heights (). The lines represent the calculated dependences based on the TE and TFE models. The points represent the experimental data for contacts annealed at 950, 1000, and 1050°C for 3 min as well as some data from [7–47]. (b) Effective barrier height () of Ni and Ni₂Si ohmic contacts to n-type (~1 × 10¹⁹ cm⁻³) 4H-SiC epiwafers versus annealing temperature/time.

(a)

(b)