Estudo De Filmes Finos De Dlc Com Diferentes Dopantes Para Aplicação Em Sensores Piezoresistivos

• Ano de defesa: 2017
• Autor(a) principal: Leal, Gabriela [UNIFESP]
• Tipo de documento: Tese
• Tipo de acesso: Acesso aberto
• Idioma: por
• Instituição de defesa: Universidade Federal de São Paulo (UNIFESP)
• Palavras-chave em Português: Piezoresistive Sensor; Dlc; Me-Dlc; Magnetron Sputtering; Piezoresistivity; Hipims; Sensor Piezoresistivo; Piezoresistividade
• Link de acesso: https://sucupira.capes.gov.br/sucupira/public/consultas/coleta/trabalhoConclusao/viewTrabalhoConclusao.jsf?popup=true&id_trabalho=5739271; http://repositorio.unifesp.br/handle/11600/50180

This work aims the study of thin films of Diamond-like Carbon (DLC) with different dopants for application in piezoresistive sensors. For this, it was performed a systematic study of the DLC thin films deposited on silicon substrate by dual magnetron sputtering technique with and without the addition of metals (Sn, W, Ag, Al and Ti) in different concentrations and with variation of sources (DC and HiPIMS), besides the deposition of nitrogen-containing DLC films (N-DLC) with reactive sputtering. Chemical and physical analyzes of the deposited films were performed in order to determine the best conditions to produce them with suitable properties for application in piezoresistive sensors. The results obtained allowed that it was possible to identify a set of samples with the desired properties, that is, the samples deposited with DC source applied to the targets of tin, tungsten and titanium with power of 15 and 30W. Piezoresistors with different layouts were produced with these most promising samples, to perform piezoresistive analysis by the beam method. Due to the instabilities in the results, piezoresistive tests were also performed using a characterization system from the thin films, where it was possible to verify that the W-DLC sample deposited with 15W in the tungsten target presented the best result due to the variation of the resistance with the increase in force occurs linearly. It was also carried out studies of the mechanical stress in piezoresistors developed using software simulation with the beam method and the simulation and decision by the sensor layout, with the choice of the square diaphragm and the complete bridge configuration. Stages of study of the microfabrication of piezoresistive sensors were carried out based on the chosen layout. Additionally, a system for the characterization of piezoresistors using the ¼ Wheatstone bridge configuration was developed and assembled. The same equipment has the possibility of characterizing the piezoresistive sensor, considering the complete bridge configuration.