Characterization of deep electron traps in 4H-SiC Junction Barrier Schottky rectifiers

• DLTS technique was used to study deep electron traps in 4H-SiC JBS rectifiers.
• Five single-peak and one dominant double-peak deep electron traps were revealed.
• The traps were attributed to impurity-related or intrinsic defects in n-type 4H-SiC epilayers.
• The dominant deep electron trap at EC – 0.68 eV was attributed to Z1/Z2 defect.

Conventional deep level transient spectroscopy (DLTS) technique was used to study deep electron traps in 4H-SiC Junction Barrier Schottky (JBS) rectifiers. 4H-SiC epitaxial layers, doped with nitrogen and grown on standard n+−4H-SiC substrates were exposed to low-dose aluminum ion implantation process under the Schottky contact in order to form both JBS grid and junction termination extension (JTE), and assure good rectifying properties of the diodes. Several deep electron traps were revealed and attributed to impurities or intrinsic defects in 4H-SiC epitaxial layers, on the basis of comparison of their electrical parameters (i.e. activation energies, apparent capture cross sections and concentrations) with previously published results.