resumo
A thermal actuator based on thin flexible lamellas of Ga2O3 was designed in order to demonstrate the potential of this semiconductor for micro-opto-electro-mechanical applications (MOEMs). The working principle of these devices is based on the thermal expansion that induces a vertical movement resultant of the lamella elongation due the self-heating/Joule effect. Upon excitation with photons, electrons or ions, intrinsic luminescence bands associated with self-trapped excitons and donor-acceptor pair recombination dominate the emission spectrum. When a current passes through the device, simultaneously with the thermal expansion, this luminescence is strongly quenched. Based on systematic Photoluminescence and Raman studies as a function of temperature and as a function of the applied power it is demonstrated that the observed luminescence quenching is directly related with the Joule heating effect. This work presents for the first time a thermal actuator based on Ga2O3 and it intends to be a stimulus for future works on MOEMs applications based on this semiconductor. (c) The Author(s) 2019. Published by ECS.
palavras-chave
SINGLE-CRYSTALS; OPTICAL-ABSORPTION; LUMINESCENCE; FIELD
categoria
Materials Science; Physics
autores
Peres, M; Fernandes, AJS; Oliveira, FJ; Alves, LC; Alves, E; Monteiro, TS; Cardoso, S; Alonso-Orts, M; Nogales, E; Mendez, B; Villora, EG; Shimamura, K; Lorenz, K
nossos autores
Filipe José Alves de Oliveira
Investigador Principalagradecimentos
This work was supported by the Portuguese Foundation for Science and Technology (FCT), under the projects UID/FIS/50010/2019 and PTDC/CTM-CTM/28011/2017, LISBOA-01-0145-FEDER-028011.