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

Abstract

Ultra-wide bandgap semiconductor diamond-based deep ultraviolet (UV) photodetector (PD) has attracted extensive attention due to its immunity to solar light on the earth and thermal stability in extremely harsh environments. To achieve high photo-response performance, high quality homoepitaxial diamonds have usually been adopted. However, the realization of the growth of high-quality diamond epilayer need expensive epitaxial equipment like microwave plasma chemical vapor deposition (MPCVD). Here, we demonstrate the PDs with tunable photoresponse properties through a simple annealing in hydrogen (H2) ambient and surface ozone treatment process. The surface holes and the nitrogen defects inside Ib diamond work together to regulate the overall photoresponse performance. The responsivity of the PDs can be adjusted from 102 A/W to 4.5x104 A/W, 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 new findings provide an alternative method and low-cost strategy for the tailoring of PDs’ performance, which can meet the different application requirements very well.