INVESTIGATION OF THE HUMIDITY EFFECTS IN A HYBRID SCHOTTKY PHOTODIODE BASED ON AZO/ZNO/PEDOT:PSS ARCHITECTURE FOR UV-VIS SENSING APPLICATIONS

Luis Henrique Tigre Bertoldo; Douglas Henrique Vieira; Mayk Rodrigues Do Nascimento (DR); FCT - UNESP; Neri Alves

Paper Title

Authors

Luis Henrique Tigre Bertoldo
Douglas Henrique Vieira
Mayk Rodrigues Do Nascimento (DR); FCT - UNESP
Neri Alves

Modality

Pôster

Subject area

Dispositivos eletrônicos e ópticos (OLED/OFET/OPVs/etc.)

Publishing Date

12/12/2023

Country of Publishing

Brasil

Language of Publishing

Inglês

Paper Page

https://www.even3.com.br/anais/workshop-do-ineo-2023/613440-investigation-of-the-humidity-effects-in-a-hybrid-schottky-photodiode-based-on-azoznopedot-pss-architecture-for

ISBN

978-65-272-0088-8

Keywords

ZnO, AZO, PEDOT:PSS, Schottky diode, photodiode, UV-Vis

Summary

Zinc Oxide (ZnO) is an n-type semiconductor with a direct bandgap of ~3.3 eV[1], making it an excellent material for use in UVA photodetectors. When ZnO is obtained using spray pyrolysis deposition of an organic precursor, at temperatures higher than 300 °C, on top of a thin film of aluminum (Al), it becomes highly doped, resulting in a material known as aluminum-doped zinc oxide (AZO). This material belongs to the family of oxide conductors transparent (OCTs) [2]. Additionally, doping ZnO with aluminum broadens its absorption spectrum to include both the visible and UVA regions. Among the various devices that can be used as photodetectors, the Schottky diode based on ZnO/PEDOT:PSS rectifying contact is an excellent option due to its compatibility with printed electronics. Here, we investigated how humidity impacts the photodiode response when exposed to UV-Vis irradiance, aiming to identify the optimal conditions to achieve its highest performance. To fabricate the devices, first, the Al bottom electrode is deposited by thermal evaporation (~15 nm), followed by the deposition of ten layers of ZnO using spray pyrolysis. The device is completed by spray coating the PEDOT:PSS top electrode onto the prepared structure. The AZO/ZnO thin film was analyzed by UV-Vis spectroscopy. The electrical study was conducted in two steps: i) electrical characterization in high humidity (~90 %) under irradiation at 628 nm, 525 nm, 470 nm, and 390 nm wavelengths, being the optical potential ~17 W/m²; and ii) electrical characterization in low humidity (~20 %) under irradiation with the same wavelengths as in the previous step. When the photodiode is in the dark at room conditions, it exhibits a rectification ratio of 383 and 50 times under low and high humidity conditions, respectively. Humidity also showed a significant impact on the photodiode’s performance under 390 nm irradiation, as an instance, the responsivity was 35.8 mA/W and 5.41 mA/W at low and high humidity conditions, respectively. In summary, we successfully fabricated a photodiode sensitive to both UV and visible light that works well under low humidity conditions. This study has demonstrated the potential to expand the applications of the ZnO/PEDOT:PSS Schottky diode as a light-sensing device. Acknowledgment FAPESP (N° 2021/01548-6), CAPES (Finance code 001), and INEO References [1] K. K. N. S. M. Sze, Physics of Semiconductor Devices, Third. San Jose, California, 2006. [2] M. S. Ozório et al., “AZO transparent electrodes grown in situ during the deposition of zinc acetate dihydrate onto aluminum thin film by spray pyrolysis,” J. Mater. Sci. Mater. Electron., vol. 30, no. 14, pp. 13454–13461, 2019, doi: 10.1007/s10854-019-01713-2.

Title of the Event: Workshop do INEO 2023
City of the Event: Nazaré Paulista
Title of the Proceedings of the event: Anais do Workshop INEO 2023
Name of the Publisher: Even3
Means of Dissemination: Meio Digital

How to cite

BERTOLDO, Luis Henrique Tigre et al.. INVESTIGATION OF THE HUMIDITY EFFECTS IN A HYBRID SCHOTTKY PHOTODIODE BASED ON AZO/ZNO/PEDOT:PSS ARCHITECTURE FOR UV-VIS SENSING APPLICATIONS.. In: Anais do workshop INEO 2023. Anais...Nazaré Paulista(SP) Hotel Estância Atibainha, 2023. Available in: https//www.even3.com.br/anais/workshop-do-ineo-2023/613440-INVESTIGATION-OF-THE-HUMIDITY-EFFECTS-IN-A-HYBRID-SCHOTTKY-PHOTODIODE-BASED-ON-AZOZNOPEDOT-PSS-ARCHITECTURE-FOR. Access in: 16/05/2025