Enhancement of local electrical conductivities in SiC by femtosecond laser modification

Enhancement of local electric conductivities induced by femtosecond laser modification in silicon carbide was studied. Current-voltage (I-V) characteristics of the laser-modified regions were measured between the ion-implanted metal contacts. Interestingly, the resistance sharply decreased in the fluence range from 5.0 to 6.7 J/cm2. The resistance at the irradiation fluence of 53 J/cm2 decreased by more than six orders of magnitude compared with the nonirradiated one. From the I-V characteristics and the scanning electron microscope observations, we conclude that the phase separation associate with the formation of classical laser induced periodic structure causes the drastic increase in electric conductivity.

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