Low-Temperature and Solution-Processed Preparation of NiOx/InGaZnO Heterostructure for UV Photodetector

Remarkable progress has been achieved in InGaZnO (IGZO) films for thin film transistors. Preserving comparable performance in optoelectronic applications as in electronic applications is challenging. The study introduces a low-temperature and solution-processed method to construct an IGZO-based heterostructure photodetector. A nickel oxide (NiO ${}_{x}\text {)}$ film was patterned on the IGZO as a buffer layer, and a compact interface was formed after annealing at a temperature of $150~^{\circ }$ C. The photo-response of the detector were characterized. The results suggest that the photocurrents and performances of the devices are promoted. Under the incident light of 254 nm, the highest photo-to-dark current ratio (PDCR) of $10^{{5}}$ is obtained. The devices possess a responsivity of 0.9 A/W and detectivity of $10^{{11}}$ Jones. Moreover, the detector shows decent flexibility and long-term stability. It maintains the initial value after operating for 30 days without encapsulation. This work provides an approach to fabricating high-performance and flexible IGZO-based optoelectronic devices.