title: Optimization of Cuprous Oxides Thin Films to be used as Thermoelectric Touch Detectors.
abstract: The electronic and optical properties of p-type copper oxides (CO) strongly depend on the production technique as it influences the obtained phases: cuprous oxide (Cu2O) or cupric oxide (CuO), the most common ones. Cu films deposited by thermal evaporation have been annealed in air atmosphere, with temperature between 225 and 375 °C and time between 1 and 4 h. The resultant CO films have been studied to understand the influence of processing parameters in the thermoelectric, electrical, optical, morphological, and structural properties. Films with a Cu2O single phase are formed when annealing at 225 °C, while CuO single phase films can be obtained at 375 °C. In between, both phases are obtained in proportions that depend on the film thickness and annealing time. The positive sign of the Seebeck coefficient (S), measured at room temperature (RT), confirms the p-type behavior of both oxides, showing values up to 1.2 mV·°C-1and conductivity up to 2.9 (Ω·m)-1. A simple detector using Cu2O have been fabricated and tested with fast finger touch events.
authors.affiliation: CENIMAT/I3N and UNINOVA, Departamento de Ciência dos Materiais, Faculdade de Ciências e Tecnologia, Universidade NOVA de Lisboa , 2829-516 Lisbon, Portugal.
authors.forename: Joana
authors.identifier: http://orcid.org/0000-0002-5996-9831
authors.initials: J
authors.lastname: Figueira
authors.affiliation: CENIMAT/I3N and UNINOVA, Departamento de Ciência dos Materiais, Faculdade de Ciências e Tecnologia, Universidade NOVA de Lisboa , 2829-516 Lisbon, Portugal.
authors.forename: Joana
authors.initials: J
authors.lastname: Loureiro
authors.affiliation: CENIMAT/I3N and UNINOVA, Departamento de Ciência dos Materiais, Faculdade de Ciências e Tecnologia, Universidade NOVA de Lisboa , 2829-516 Lisbon, Portugal.
authors.forename: José
authors.initials: J
authors.lastname: Marques
authors.affiliation: CENIMAT/I3N and UNINOVA, Departamento de Ciência dos Materiais, Faculdade de Ciências e Tecnologia, Universidade NOVA de Lisboa , 2829-516 Lisbon, Portugal.
authors.forename: Catarina
authors.initials: C
authors.lastname: Bianchi
authors.affiliation: CENIMAT/I3N and UNINOVA, Departamento de Ciência dos Materiais, Faculdade de Ciências e Tecnologia, Universidade NOVA de Lisboa , 2829-516 Lisbon, Portugal.
authors.forename: Paulo
authors.initials: P
authors.lastname: Duarte
authors.affiliation: Department of Micro and Nanosciences, Aalto University , P.O. Box 13500, FI-00076 Aalto, Finland.
authors.forename: Mikko
authors.initials: M
authors.lastname: Ruoho
authors.affiliation: Department of Micro and Nanosciences, Aalto University , P.O. Box 13500, FI-00076 Aalto, Finland.
authors.forename: Ilkka
authors.initials: I
authors.lastname: Tittonen
authors.affiliation: CENIMAT/I3N and UNINOVA, Departamento de Ciência dos Materiais, Faculdade de Ciências e Tecnologia, Universidade NOVA de Lisboa , 2829-516 Lisbon, Portugal.
authors.forename: Isabel
authors.initials: I
authors.lastname: Ferreira
keywords: Seebeck; copper oxide; postdeposition annealing; thermal evaporation; thin films