Year: 2024
Type: article
Abstract: Measurements of the electrical dark conductivity σD of undoped and carbon‐doped β‐Ga2O3 thin films reveal a metastable increase upon illumination with sub‐bandgap light. In the relaxed state, σD shows activated behavior for T > 250 K with an activation energy of 0.68 and 0.63 eV for undoped and C‐doped β‐Ga2O3, respectively. For T < 250 K, σD approaches a constant value of ≈6 × 10−12 Ω−1 cm−1. Illumination with sub‐bandgap light results in an increase of the dark conductivity by up to 6 orders of magnitude. This state is metastable and relaxes with time. The data indicate the presence of a broad distribution of localized states in the bandgap. The time and temperature dependence of the relaxation is investigated for doped and undoped samples. The data can be described by a sum of two and three stretched exponential decays for undoped and carbon‐doped β‐Ga2O3, respectively. From the time constants of the decays, the energetic depth of the localized defect states is estimated.
Source: physica status solidi (b)
Institution: Helmholtz-Zentrum Berlin für Materialien und Energie
Language: English
Topic: Ga2O3 and related materials
Field: Materials Science
Domain: Physical Sciences
Open Access status: hybrid
Estimated APC paid: $3,650
Funder: European Commission
OpenAlex ID: W4405018699