info:eu-repo/semantics/article
Resistivity humidity sensors based on hydrogenated amorphous carbon films
Fecha
2019-02Registro en:
Epeloa, Javier Eduardo; Repetto, Carlos Enrique; Gomez, Bernardo Jose Armando; Nachez, Juan Lucas; Dobry, Ariel Oscar; Resistivity humidity sensors based on hydrogenated amorphous carbon films; IOP Publishing; Materials Research Express; 6; 2; 2-2019; 1-8; 025604
2053-1591
CONICET Digital
CONICET
Autor
Epeloa, Javier Eduardo
Repetto, Carlos Enrique
Gomez, Bernardo Jose Armando
Nachez, Juan Lucas
Dobry, Ariel Oscar
Resumen
We have studied the humidity dependence of the electrical properties in hydrogenated amorphous carbon (a-C:H) films. The films were prepared in two stages combining the techniques of physical deposition in vapor phase evaporation (PAVD) and plasma pulsed nitriding. They were deposited over printed circuit boards made of synthetic resin FR2, predesigned to measure DC and AC transport. The Raman spectrum showed a broad peak whose two components are characteristics of a-C:H. By treating the sample in N2-H2 plasma, the impedance became intrinsically sensitive to the relative humidity (RH) of the surrounding media. We observed that when RH increased, the electrical impedance (Z) of the films diminished. The complex impedance spectroscopy method was used to analyze the interaction between the water molecules and the a-C:H film. The main contribution to the humidity dependency of Z came from the resistivity component. The present work provides a fundamental support to develop humidity sensors based on the variation of the impedance of a-C:H films.