Large ferro–pyro–phototronic effect in 0.5Ba(Zr_0.2Ti_0.8)O₃–0.5(Ba_0.7Ca_0.3)TiO₃ thin films integrated on silicon for photodetection

Abstract

Coupling together the ferroelectric, pyroelectric, and photovoltaic characteristics within a single material is a novel way to improve the performance of photodetectors. In this work, we take advantage of the triple multifunctionality shown by 0.5Ba(Zr 0.2 Ti 0.8 )O 3 -0.5(Ba 0.7 Ca 0.3 )TiO 3 (BCZT), as demonstrated in an Al/Si/SiO x /BCZT/ITO thin-film device. The Si/SiO x acts as an n-type layer to form a metal-ferroelectric-insulator-semiconductor heterostructure with the BCZT, and with Al and ITO as electrodes. The photo-response of the device, with excitation from a violet laser (405 nm wavelength), is carefully investigated, and it is shown that the photodetector performance is invariant with the chopper frequency owing to the pyro-phototronic effect, which corresponds to the coupling together of the pyroelectric and photovoltaic responses. However, the photodetector performance was significantly better than that of the devices operating based only on the pyro-phototronic effect by a factor of 4, due to the presence of ferroelectricity in the system. Thus, after a poling voltage of −15 V, for a laser power density of 230 mW/cm 2 and at a chopper frequency of 400 Hz, optimized responsivity, detectivity, and sensitivity values of 13.1 mA/W, 1.7 × 10 10 Jones, and 26.9, respectively, are achieved. Furthermore, ultrafast rise and fall times of 2.4 and 1.5 µs, respectively, are obtained, which are 35,000 and 36,000 times faster rise and fall responses, respectively, than previous reports of devices with the ferro-pyro-phototronic effect. This is understood

Inorganic ferroelectric thin films and their composites for flexible electronic and energy device applications: current progress and perspectives

“…Even so, there have been limited studies on flexible devices. 74,118 To summarize, we strongly believe that flexible IFEs have a significant role to play in energy harvesting, IR sensing, and energy storage applications. We anticipate that this article will help the journey of future work on flexible IFEs to fabricate long-lasting reliable electronic devices.…”

Tri-layered Si/Co3O4/ZnO heterojunction for high-performance visible photodetection

“…The electrical and photoelectrical measurements were performed as described in previous works. 2,17 The illumination of the devices was provided by a semiconductor laser with a wavelength of 405 nm and power density in the range 9.35 up to 251 mW cm −2 controlled with a TTL signal, and by light-emitting diodes with a power density of 0.25 mW cm −2 and different wavelength (405, 470, 515, 590, 625, 850 nm).…”

High-performance and self-powered visible light photodetector using multiple coupled synergetic effects

“…5 In particular, the wide bandgap semiconductor-based PDs for the UV to visible wavelength range (UV-Vis) have shown the benefits of having a simple structure, facile miniaturization, and robustness against radiation in harsh conditions. 6 In this case, metal oxides, such as ZnO and TiO 2 , owing to their advantages of non-toxicity, abundance in nature, facile synthesis and good stability, have been widely investigated for selfpowered UV-Vis photodetection. 7,8 In the case of ZnO-based PDs, the PV effect can be coupled with the pyroelectric effect into the so-called pyro-phototronic effect 5,9 to further boots the PD performance given the fact that ZnO is a pyroelectric material.…”