Autor(es)

Vieira, Douglas Henrique ; Nogueira, Gabriel Leonardo ; de Oliveira, Rafael Furlan ; Gomes, Henrique Leonel ; Alves, Neri

• Tipo de documento: Artigo Científico
• Fonte: ACS APPLIED ELECTRONIC MATERIALS; v. 7, n. 17, p. 11-pg., 2025-08-28.

Resumo

This study reports the fabrication and electrical characterization of metal-electrolyte-semiconductor (MES) capacitors based on printed ZnO as a semiconducting layer and a cellulose-based eco-friendly electrolyte. The results demonstrate that MES capacitors behave similarly to their solid-state metal-insulator-semiconductor (MIS) counterparts. Capacitance-voltage measurements show well-defined charge saturation and depletion plateaus, and the Mott-Schottky plots exhibit the expected linear behavior, allowing the extraction of the semiconductor free carrier density. Upon UV light exposure with varying irradiance, the flat-band voltage shifts consistently with a light-induced increase in free carrier density, and the capacitance increases due to trap filling. These behaviors are confirmed by measurements using a phototransistor structure. The frequency response of the MES capacitors also reveals low-frequency relaxation peaks in the capacitance spectrum, which align with a continuous distribution of interface state density reaching approximately similar to 4.86 x 1013 cm-2<middle dot>eV-1. These findings confirm that MES capacitors can effectively quantify electronic states at the electrolyte/semiconductor interface. This capability, along with a high capacitance ratio [C light - C dark]/C dark at very low voltages, is particularly valuable for applying MES devices in a wide range of sensing applications, especially in field-effect photodetectors. (AU)

• Processo FAPESP: 20/12282-4 - Desenvolvimento de transistores verticais de efeito de campo com eletrólito no gate para fotodetectores UV
• Beneficiário: Douglas Henrique Vieira
• Modalidade de apoio: Bolsas no Brasil - Doutorado
• Processo FAPESP: 21/06238-5 - Materiais 2D funcionalizados processados em solução: desenvolvimento de sensores e biossensores elétricos prototipáveis
• Beneficiário: Rafael Furlan de Oliveira
• Modalidade de apoio: Auxílio à Pesquisa - Jovens Pesquisadores