We report the emission kinetics of a single-electron trap (E1, E C–0.63 eV) in Sn-doped ( 2 ˉ 01) β-Ga2O3 crystals studied using deeplevel transient spectroscopy (DLTS). The time constant ( τ ) of the electrons emitted from the trap level E1 was thoroughly investigated as a function of the temperature and the electric field (E-field) . The temperature-dependence τ of E1 was extracted by both the temperature-scanning and isothermal modes of DLTS. It was found that the emission process accelerated exponentially from 200 K to 350 K. The E-field dependence of the emission time constant could be divided into two regimes for all measurement steps (250–325 K). In the low-electric-field regime, the emission time constant of the trap decreased slightly with a strengthened E-field. With a further enhancement of the E-field (E > 1.76 MV cm−1), the field-enhanced emission rate was accurately modeled by the Poole–Frenkel effect; the accelerated emission process was attributed to a reduction of the Coulomb well barrier for the donor-like trap E1.

By deep level transient spectroscopy (DLTS), emission and capture behaviors have been explicitly investigated for a single electron trap in a Si-doped β-Ga2O3 epilayer. Trap characteristics including activation energy for emission (E emi = 0.8eV), capture cross-section of 6.40×10-15 cm2 and lambda-corrected trap concentration (NTa ) of 2.48×1013 cm-3 were revealed, together with non-emission region width (λ = 267.78nm). By isothermal DLTS, in addition to the impact of temperature, electric-field-enhanced trap emission kinetics were studied. When a relatively low electric field (E ≤ 1.81×105V/cm at 330K), emission kinetics of the trap was modeled to comply with phonon-assisted tunneling (PAT), whereas the emission process was regarded to be dominated by direct tunneling (DT) for a relatively high electric field (E ≥ 1.81×105V/cm at 330K). A thermal-enhanced capture process has also been revealed and quantitatively studied, where a capture barrier energy of 0.15eV was extracted.

Properties of minority carrier (electron) traps in Schottky type p-GaN gate high electron mobility transistors were explicitly investigated by optical deep level transient spectroscopy (ODLTS). By temperature-scanning ODLTS, three electron traps, namely, E1, E2, and E3, were revealed, together with activation energy, capture cross section, and trap concentration. A thermally accelerated electron-releasing process of traps was quantitatively studied by Laplace ODLTS with individual emission time constant disclosed. At 300 K, the emission time constant was determined to be 0.21 and 1.40 s for E2 and E3, respectively, which adjacently existed in the bandgap and held activation energies of over 0.6 eV. As varying the optical injection pulse duration, a three-dimensional mapping of capacitance transient was obtained for each trap, attesting to the electron capture capability of each trap. By varying the reverse bias, the analysis of the ODLTS signal amplitude indicates that all three electron traps are located inside the p-GaN layer rather than the surface defect related.