The aim of this work was the electrical characterization of HMDS and/or fluorinated plasma deposited thin films and their double layers or composites. Films were deposited on silicon wafers using homemade DC powered equipment. Electrical characterization measured the variation of ca-pacitance as a function of voltage if films were exposed to airflow saturated with 2-propanol or n-hexane vapours. Capacitance on HMDS films changes due to exposure but a partial recovery is easily obtained using airflow. Fluorinated film has low sensitivity and double layers show retention due to reactant permeation through the fluorinated film. Composite films show intermediary behaviour and the recovery of capacitance values might be possible. Therefore, HMDS and fluorinated films are promising for sensors development. Nonetheless, whereas HMDS films seem to be useful on any capacitive sensor device, due to the difficulty in signal recovery, fluorinated films are more adequate on one-way sensors.
Biografia do Autor
Roberto da Rocha Lima, Institute of Physics, University of São Paulo, IFUSP, SP
Obtained his degree in Technology in Materials, Process and Electronics Devices from the Faculty of Technology of São Paulo in 1996 and his M. Sc. and Ph. D. degrees in Electrical Engineering from the Engineering School, University of São Paulo in 2004 and 2009, respectively
Main research interests - Since 1997, he has acted as a researcher in the Institute of Physics of University of São Paulo, where he develops new plasma equipment and studies its applications
