Effect of the energy of bombarding electrons on the conductivity of n-4H-SiC (CVD) epitaxial layers

Irradiation effect of primary knock-on atoms on conductivity compensation in N-type 4H-SiC Schottky diode under various irradiations

“…Fluence 16 1.75 1.92 1×10 14 1.02 1.00 4.81 100 3.27×10 16 1.79 1.96 1×10 15 1.02 1.00 4.83 101 3.25×10 16 1.9 2.07 2×10 16 1.03 interface traps produced by irradiation were also an important reason for the barrier height reduction. The increasement in series resistance indicates that the reason could be the decreasing of the mobility and the free carrier concentration, or the compensation of doping in the semiconductor [17][18][19].…”

“…By the equation (13), the fraction f FP for 1 MeV electron, 25 MeV C and 40 MeV Si are 13%, 30% and 60%, respectively. Assuming that hot PKAs (energetic PKAs, in the right hand of PKA spectrum) produce dissociated FPs, according to the inverse-square law, we can calculate the boundary energy E ch that produces dissociated FPs: From the reference [15], Kozlovski proved that 122 eV is the characteristic energy of C atoms in SiC (when carbon atoms receive energy of 122 eV, they will leave the spontaneous-recombination area to form stable RDs leading to the conductivity compensation in n-SiC). The recombination radius is ∼8 Å corresponding to four a 0 (the distance between the nearest carbon atoms) [15].…”

“…These hot PKAs are only ∼20% percent of total PKAs, but a C atom with ∼661 eV and ∼1136 eV create in a cascade approximately 14 and 25 vacancies, respectively. Under these conditions, a cascade yields microscopic regions with wide of 20-50 Å [15], with up to ten displacements occurring in these microscopic regions. However, the high concentration of vacancies in these regions lead to formation of divacancies, multivacancies and complexes of these vacancies with impurity atoms rather than single vacancy.…”

“…The general explanation is that heavy ions produce more displacement damage in SiC due to greater momentum, leading to more conductivity recombination. Theoretical calculation is a good way to explain this phenomenon, but the calculation of conductivity compensation is mainly related to proton and electron irradiation [14,15]. Until now, there is almost no clear conclusion about the effect of the heavy ions irradiation on conductivity compensation.…”

Electrophysical and Optical Properties of 4H-SiC UV Detectors Irradiated with Electrons

“…In particular, it was demonstrated that the irradiation of 4H-SiC by 0.9 MeV electrons with different doses causes the change of the material conductivity [4]. The rate of charge carrier removal was determined [5] as well as the formation of vacancies in the both sublattices of SiC was detected [6]. Spectrometric properties of the SiC based devices under electron irradiation were studied [7].…”