Al-doped ZnO Thin Films via Sputtering: Influence of Structural Defects on Ozone Gas Sensitivity

Autor(es)

Douglas Henrique Sales ^[1] ; Ramon Resende Leite ^[2] ; Julio Cesar Camilo Albornoz Diaz ^[3] ; Amanda Akemy Komorizono ^[4] ; Maria Ines Basso Bernardi ^[5] ; Valmor Roberto Mastelaro ^[6] ; Elson Longo ^[7] ; Silvio Rainho Teixeira ^[8] ; Agda Eunice de Souza ^[9]

Afiliação do(s) autor(es)

^[1] Universidade Estadual Paulista (UNESP). Faculdade de Ciências e Tecnologia - Brasil

^[2] Universidade de São Paulo. Instituto de Física de São Carlos - Brasil

^[3] Universidade de São Paulo. Instituto de Física de São Carlos - Brasil

^[4] Universidade de São Paulo. Instituto de Física de São Carlos - Brasil

^[5] Universidade de São Paulo. Instituto de Física de São Carlos - Brasil

^[6] Universidade de São Paulo. Instituto de Física de São Carlos - Brasil

^[7] Universidade Federal de São Carlos. Laboratório Interdisciplinar de Eletroquímica e Cerâmica - Brasil

^[8] Universidade Estadual Paulista (UNESP). Faculdade de Ciências e Tecnologia - Brasil

^[9] Universidade Estadual Paulista (UNESP). Faculdade de Ciências e Tecnologia - Brasil

• Tipo de documento: Artigo Científico
• Fonte: MATERIALS RESEARCH-IBERO-AMERICAN JOURNAL OF MATERIALS; v. 27, 2024-10-21.

Resumo

Nowadays, few studies have reported on the sensitivity of thin films of Al-doped ZnO to ozone. This gas can become harmful to health depending on its environmental concentration. This work presents the sensor response to ozone gas of pure ZnO and Al-doped thin films, prepared by sputtering with varying deposition times. Ceramic targets prepared by SSR, compacted at 65MPa, sintered at 950°C, with densities ranging from 74-97% of the theoretical density, depending on the dopant content were used. The films showed an increase in thickness with deposition time and a preferential growth in the (002) plane of the ZnO structure. Slight changes in the band gap value occurred with increasing Al, whose presence in the ZnO lattice was confirmed by XPS. The sensitivity results to ozone showed that the performance of the films decreased with the Al-doping, which could be attributed to the defects formation related to oxygen in the lattice during Zn-Al substitution or to the greater densification of the films. Although the results showed a decrease in the sensor properties, all films are sensitive to ozone, including the low concentrations of 50 ppb, a limit considered for a maximum daily average for human exposure, established by the WHO. (AU)

• Processo FAPESP: 13/07296-2 - CDMF - Centro de Desenvolvimento de Materiais Funcionais
• Beneficiário: Elson Longo da Silva
• Modalidade de apoio: Auxílio à Pesquisa - Centros de Pesquisa, Inovação e Difusão - CEPIDs