High‐Performance Self‐Assembled ZnO Nanowrinkle Network Structured Photodetectors

Herein, the effect of prebake temperature on the surface structure of zinc oxide (ZnO) nanowrinkle structures formed in a sol–gel growth process for UV photodetection is demonstrated. The sol–gel solutions are spin‐coated on glass and c‐plane sapphire substrates, and the resulting ZnO films are subjected to prebake and crystallization processes at 800 °C for an hour. In the sol–gel process, the prebake process is crucial in forming the nanowrinkle structure on the surface of the ZnO film. The maximum nanowrinkle structure of ZnO film is achieved at the prebake temperature of 150 °C. In addition to the formation of the optimized nanowrinkle structure, the UV response of the photodetector is further enhanced through the prebake temperature control. The nanowrinkle network structure significantly improves the optical absorbance and photoluminescence characteristics of the ZnO film, leading to high photocurrent, photoresponsivity, and external quantum efficiency for UV light. The results demonstrate the potential of sol–gel‐derived ZnO photodetectors with nanowrinkle network structures for UV sensing applications.