Ultraviolet photodetectors based on ferroelectric depolarization field

Ultraviolet (UV) photodetectors are extensively adopted in the fields of the Internet of Things, optical communications and imaging. Nowadays, with broadening the application scope of UV photodetectors, developing integrated devices with more functionalities rather than basic photo-detecting ability are highly required and have been triggered ever-growing interest in scientific and industrial communities. Ferroelectric thin films have become a potential candidate in the field of UV detection due to their wide bandgap and unique photovoltaic characteristics. Additionally, ferroelectric thin films perform excellent dielectric, piezoelectric, pyroelectric, acousto-optic effects, etc., which can satisfy the demand for the diversified development of UV detectors. In this review, according to the different roles of ferroelectric thin films in the device, the UV photodetectors based on ferroelectric films are classified into ferroelectric depolarization field driven type, ferroelectric depolarization field and built-in electric field co-driven type, and ferroelectric field enhanced type. These three types of ferroelectric UV photodetectors have great potential and are expected to promote the development of a new generation of UV detection technology. At the end of the paper, the advantages and challenges of three types of ferroelectric UV photodetectors are summarized, and the possible development direction in the future is proposed.