Raman Characterization of Carbon Clusters at the 4H-SiC/Ni Interface of SiC Power Devices Against Different Annealing Methods

In this paper, the ohmic contact resistance, the structure of interface materials and the characteristics of carbon clusters at the 4H-SiC/Ni interface are examined to gain an insight into the formation of ohmic contact between Ni and 4H-SiC of SiC power devices. In this work, the experiment results show that the pulsed laser annealing process can obtain low ohmic contact resistance on 4H-SiC. In addition, the characterization of carbon cluster by Raman spectroscopy is discussed. It is concluded that more carbon vacancies and smaller carbon cluster particle size can be obtained by pulsed laser annealing. The results of this study provide insights into the ohmic contact interface and show that pulsed laser annealing is attractive ohmic contact process for high performance SiC power devices.