Investigation of a minority carrier trap in a NiO/β-Ga2O3 p–n heterojunction via deep-level transient spectroscopy

Abstract

The properties of a minority carrier (hole) trap in β-Ga2O3 have been explicitly investigated using a NiO/β-Ga2O3 p–n heterojunction. Via deep-level transient spectroscopy, the activation energy for emission (E emi) and the hole capture cross section (σp ) were derived to be 0.10 eV and 2.48 × 10−15 cm2, respectively. Temperature-enhanced capture and emission kinetics were revealed by the decrease in the capture time constant (τc ) and emission time constant (τe ). Moreover, it was determined that the emission process of the minority carrier trap is independent of the electric field. Taking carrier recombination into account, a corrected trap concentration (N Ta) of 2.73 × 1015 cm−3 was extracted, together with an electron capture cross section (σn ) of 1.42 × 10−18 cm2. This study provides a foundation for the comprehension of trap properties in β-Ga2O3, which is crucial for overcoming self-trapped hole effects when obtaining p-type β-Ga2O3 materials and performance enhancement of β-Ga2O3-based power devices.