High sensitivity and fast response self-powered PbSe ultraviolet pulsed photodetectors based on the transverse thermoelectric effect

• Published in: Applied surface science 2023-06, Vol.621, p.156872, Article 156872
• Main Authors: Chen, Mingjing, Chen, Xuyang, Fang, Lide, Yan, Guoying, Ning, Xingkun, San, Xingyuan, Wang, Shufang
• Format: Article
• Language: English
• Subjects: Inclined PbSe thin film; Self-powered ultraviolet pulsed photodetector; Transverse thermoelectric effect
• ISSN: 0169-4332; 1873-5584
• DOI: 10.1016/j.apsusc.2023.156872

[Display omitted] •We investigated the TTE response of the inclined PbSe films upon UV pulsed illumination.•Gigantic TTE voltage exceeding several tens of volts was obtained.•Moreover, the TTE voltage exhibited an ultrafast response in the order of ns.•Both the detection sensitivity and the figure of merit obtained in PbSe films are much higher than those reported in most of the complex oxide films as well as the commercial device, demonstrating the great potential application of PbSe for the high-performance self-powered UV pulsed photodetectors. Light-induced transverse thermoelectric (TTE) effect has attracted extensive attentions because of the great potential application in self-powered photodetectors. In this paper, we report the ultraviolet pulsed light-induced TTE effect in the inclined PbSe thin films. Without any external voltage applied, gigantic open-circuit voltage signals with ultrafast responses in the order of nanoseconds were obtained when the film surface was irradiated by a 308 nm pulsed laser. The voltage sensitivity Rs can reach up to ∼7.75 V/mJ and the figure of merit Fm is as high as ∼350 mV/ns, both of which are higher than the best values reported in most of complex oxide thin films. In addition, the experimental results reveal that the polarity of the induced voltage will immediately reverse when the film is irradiated from the substrate side and the amplitudes of the voltage are linearly proportional to sin2α (α is the inclination angle of the films). Here, the anisotropy of the Seebeck coefficient is used to explain the origin of the TTE voltage. The results demonstrate the great potential application of PbSe thin film for the high sensitivity and fast response self-powered ultraviolet pulsed photodetectors.