The Effect of Doping On Nitrogen Activation Energy Level In 4H-SiC

Abstract

AbstractThermal admittance spectroscopy has been used to study the thermal activation energy of nitrogen at the hexagonal and cubic sites in 4H-SiC as function of net doping concentration. The net doping concentration- of te samples, which was determined from 1/C2 vs. V plots, ranges from 1.5 × 1014 cm−3 to 4 × 1018 cm−3. The thermal activation energy of nitrogen was determined to be Ee O.054 eV and Ee O.101 eV for nitrogen at hexagonal and cubic sites respectively for ND - NA ≤ 1016 cm−3. As the free carrier concentration increases from 1016 cm−3 to 1.0 × 1018 cm3, the thermal activation energy of nitrogen at the hexagonal site decreases from 54 meV to 24 meV. At ND - NA ≥1.0 × 10 cm−3 hopping conduction is the only conduction mechanism and has an activation energy of 3-9 meV.