Laser micromachining of Circular Transmission Line Model (CTLM) of Al contacts on n-type SiC/Si chips

An array of Circular Transmission Line Model (CTLM) metal contacts was deposited onto the upper surface of the n-SiC/Si chips using laser micromachining as an alternative to standard photolithography technique. Thin epitaxial n-type 3C-SiC/Si chips were used since no current leakage observed in previous studies. Various laser energies were used for the CTLM pattern transfer. Low values of ρc were obtained such 19×10^-4 Ωcm² was produced despite of different rings´ diameters at the lower laser energy strength. However, high laser penetration had caused higher contact resistances approximately 20 times. This is probably attributed to the surface degradation of 3C-SiC.