Department Of Physics
Permanent URI for this communityhttps://kr.cup.edu.in/handle/32116/57
Browse
3 results
Search Results
Item Polarization-independent enhancement in UV photoconductivity of BiFeO3/Sn:In2O3 heterostructure(Elsevier B.V., 2023-05-08T00:00:00) Banda, Rajender Reddy; Halge, Devidas I.; Narwade, Vijaykiran N.; Kaawash, Nabeel M.S.; Thabit, Mohammed Y.H.; Alegaonkar, Prashant S.; Bogle, Kashinath A.Currently, polarization-dependent transport in ferroelectric materials under optical illumination is gaining a lot of attention in optoelectronics. This idea is implemented on BiFeO3 to illustrate its UV�Visible light photodetection property, however, naturally occurring bismuth or oxygen vacancies serve a major disadvantage as they interfere with its polarization ability. It is very difficult to overcome this defect issue in bismuth-based perovskites, therefore, based on this herein an enhancement in the photoconductive property of polycrystalline BiFeO3 thin film deposited via spray pyrolysis technique on Sn:In2O3 coated glass substrate is demonstrated without polarizing it. An extraordinary photodetection behavior with higher photoresponsivity (1.01 A/W) and external quantum efficiency (364) as well as faster response speed (6 ms) even under low UV illumination (340 nm) and lower applied bias of 2 V is observed. The roles of the BiFeO3�Sn:In2O3 interface, as well as the adsorption/desorption of oxygen molecules on the surface of BiFeO3 layers, were highlighted for the ferroelectric material's UV photodetector application. � 2023 Elsevier B.V.Item Rationally designed state-of-the-art approach for enhancing the ultraviolet photon detection performance of ZnO thin film(Elsevier B.V., 2022-10-07T00:00:00) Kaawash, Nabeel M.S.; Halge, Devidas I.; Narwade, Vijaykiran N.; Alegaonkar, Prashant S.; Bogle, Kashinath A.Here, we demonstrate a simple and effective state-of-the-art (surface passivation) approach for enhancing the UV photo detection performance of ZnO thin films synthesized via spray pyrolysis. The surface passivated Ag/ZnO/Ag device (using polyvinyl alcohol layer) has low dark current of 1.1 nA as compared with the device without surface passivation (0.04 ?A). The significant decay in the dark current after surface passivation is due the reduction in the density of surface oxygen vacancies confirmed by PL measurements. The UV photon detection capability of the surface passivated ZnO thin film exhibits a significantly high photo response (3675), high photosensitivity (3.6 � 105), photo-responsivity (0.6 A/W) and fast response time (0.6 ms) under UV light (340 nm, 140 ?W/cm2). This straightforward approach superimposes surface defects, making the ZnO thin film more suitable for a wide range of electronic device applications while preserving the material's intrinsic properties. � 2022 Elsevier B.V.Item Highly stable and sensitive photon detection performance of ZnO thin film for ultraviolet light(Elsevier B.V., 2022-04-14T00:00:00) Kaawash, Nabeel M.S.; Kejriwal, Nubbh; Halge, Devidas I.; Narwade, Vijaykiran N.; Rana, Abhimanyu S.; Dadge, Jagdish W.; Jejurikar, Suhas M.; Alegaonkar, Prashant S.; Bogle, Kashinath A.The photo detection characteristics of spray pyrolysis deposited ZnO thin film on glass substrate at 250 OC was demonstrated for fabrication of highly stable visible-blind UV photodetector. This photodetector exhibits lower dark current < 0.04 ?A, higher UV photosensitivity ?4750, responsivity of 0.14 A/W and detectivity of 1.24 � 1012 Jones at an average intensity of 140 ?W/cm2 of 340 nm. This Ag/ZnO/Ag device show excellent photo response (rise and decay) time of ?4 and 6 ms with external quantum efficiency of 51%. The observed photocurrent in the device is associated with adsorption and light-induced desorption of oxygen from the defect sites on the film surfaces. The adsorbed oxygen removes the electron trap centers and increasing the free carrier density in ZnO. � 2022 Elsevier B.V.