Phonon-Assisted Tunneling from Z1/Z2 in 4H-SiC

n-Type 4H-SiC bulk samples with a net doping concentration of 2.5 × 10¹⁷ cm⁻³ were irradiated at room temperature with 1-MeV electrons. The high doping concentration plus a reverse bias of up to −13 V ensures high electric field in the depletion region. The dependence of the emission rate on the electric field in the depletion region was measured using deep-level transient spectroscopy (DLTS) and double-correlation deep-level transient spectroscopy (DDLTS). The experimental data are adequately described by the phonon-assisted tunneling model proposed by Karpus and Pere.