Drift mobility in 4H-SiC Schottky diodes

In this work, the temperature dependence of the mobility along the c axis in 4H-SiC was determined from the current voltage (I-V) characteristics of Schottky diodes in the temperature range 80–700 K. The procedure used series resistance measurements in Schottky diodes for extracting the mobility values in the epitaxial layer. For a dopant concentration of 1.2×1016cm−3, at room temperature, a mobility value of 724cm2∕(Vs) was found, which decreased to 48.6cm2∕(Vs) at 700 K. In the temperature range 200–700 K, a dependence of the mobility as T−3 was determined.