Process Oxygen Flow Influence on the Structural Properties of Thin Films Obtained by Co-Sputtering of (TeO2)x-ZnO and Au onto Si Substrates

Leonardo Bontempo; Sebastião G Dos Santos Filho; Luciana R P Kassab

doi:10.3390/nano10091863

Process Oxygen Flow Influence on the Structural Properties of Thin Films Obtained by Co-Sputtering of (TeO₂)_x-ZnO and Au onto Si Substrates

Nanomaterials (Basel). 2020 Sep 17;10(9):1863. doi: 10.3390/nano10091863.

Authors

Leonardo Bontempo^{1

2}, Sebastião G Dos Santos Filho¹, Luciana R P Kassab²

Affiliations

¹ Laboratório de Sistemas Integráveis, Escola Politécnica da Universidade de São Paulo, Av. Prof. Luciano Gualberto, 158, Travessa 3, 05508-900 São Paulo, SP, Brazil.
² Laboratório de Tecnologia em Materiais Fotônicos e Optoeletrônicos, Faculdade de Tecnologia de São Paulo, Centro Paula Souza, Praça Cel. Fernando Prestes, 30, 01124-060 São Paulo, SP, Brazil.

Abstract

In this study, we investigated the structural properties of TeO₂-ZnO (TZ) and TeO₂-ZnO-Au (TZA) thin films sputtered under different oxygen concentrations and either annealed or not annealed at 325 °C in air for 10 or 20 h. The lattice changes of the tellurium oxide were shown to be inherent in the polymorph properties of the α and β phases. The β phase was formed for null oxygen flow and the α phase was formed for different oxygen flows (0.5-7.0 sccm) during TZ and TZA sputtering. Au was encountered in its single phase or as AuTe₂. The annealing had very little influence on the α and β phases for both TZ and TZA. It is worth noting that SiO₂ and orthotellurate anions are both formed for not-null oxygen flow. An electrochemical mechanism was proposed to explain the SiO₂ growth at the TZ/Si or TZA/Si interface, taking the orthotellurate anion as oxidizing agent into account.

Keywords: TeO2 phases; co-sputtering; gold nanoparticles; tellurate; thin films.

Abstract

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