Self-Driven Ultraviolet Light and Imaging Detectors Composed of CuI/4H-SiC Heterostructures With an Ultrahigh Photovoltage Responsivity

In this work, we present an efficient ultraviolet (UV) light detector, which is constructed by simply evaporating CuI atop 4H-SiC to form a heterostructure. Due to the pronounced photovoltaic activity, the heterostructure can function as a self-driven UV light detector featuring a large photovoltage of 1.16 V. A representative device reaches a peak photocurrent responsivity of around 130.7 mA/W, an extremely high photovoltage responsivity of 1.46 × 10<sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"><roman>8</roman></sup> V/W, a large specific detectivity of 5.73 × 10<sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"><roman>12</roman></sup> Jones, a weak dark current of about 0.8 pA, and a respectable linear dynamic range (LDR) of 132.7 dB, together with a rapid response speed of 7.3/4.5 ms, at the UV wavelength range at self-driven mode. What is more, this solid-state UV photodetector has robust operational durability and stability. The prominent UV photoresponse performance guarantees the detector with capacity to serve as a UV optical imager, showing the possibility for utilization in UV optoelectronic devices and systems in future.