Photo-response performance regulation of a type-Ib diamond-based photodetector by H2 annealing and ozone treatment†

Abstract

Deep ultraviolet (DUV) photodetectors (PDs) based on ultra-wide bandgap semiconductor diamond-based have attracted extensive attention due to the immunity to solar light on the earth and thermal stability in extremely harsh environments. However, the preparation of a high-quality and high-purity single-crystal diamond epilayer remains a major obstacle to achieve high photo-response performance. Here, we demonstrate that diamond PDs with tunable photoresponse properties can be obtained on type-Ib diamonds through simple annealing in ambient H₂ and a surface ozone treatment process. The surface holes and the nitrogen defects inside the type-Ib diamond work together to regulate the overall photoresponse performance. The responsivity of the PDs can be adjusted from 84.3 A W⁻¹ to 2.65 × 10⁴ A W⁻¹, and the response time can be modulated from 42.5 s to less than 240 ms. The achievement of photo response performance modulation of PDs originates from the cooperative effect of deep natural nitrogen defects and surface states. Thus, our findings provide an alternative method and facile strategy for the tailoring of PDs’ performance, which can meet different application requirements.