title: Piezoresistive effects in controllable defective HFTCVD graphene-based flexible pressure sensor.
abstract: In this work, the piezoresistive effects of defective graphene used on a flexible pressure sensor are demonstrated. The graphene used was deposited at substrate temperatures of 750, 850 and 1000 °C using the hot-filament thermal chemical vapor deposition method in which the resultant graphene had different defect densities. Incorporation of the graphene as the sensing materials in sensor device showed that a linear variation in the resistance change with the applied gas pressure was obtained in the range of 0 to 50 kPa. The deposition temperature of the graphene deposited on copper foil using this technique was shown to be capable of tuning the sensitivity of the flexible graphene-based pressure sensor. We found that the sensor performance is strongly dominated by the defect density in the graphene, where graphene with the highest defect density deposited at 750 °C exhibited an almost four-fold sensitivity as compared to that deposited at 1000 °C. This effect is believed to have been contributed by the scattering of charge carriers in the graphene networks through various forms such as from the defects in the graphene lattice itself, tunneling between graphene islands, and tunneling between defect-like structures.
authors.affiliation: Nanoelectronics Lab, MIMOS Berhad, Technology Park Malaysia, Kuala Lumpur 57000, Malaysia.|School of Mechanical Engineering, USM Engineering Campus, Universiti Sains Malaysia, Nibong Tebal, Pulau Pinang 14300, Malaysia.
authors.forename: Muhammad Aniq Shazni
authors.initials: MA
authors.lastname: Mohammad Haniff
authors.affiliation: Low Dimensional Materials Research Centre, Physics Department, Faculty of Science, University of Malaya, Kuala Lumpur 50603, Malaysia.
authors.forename: Syed
authors.initials: S
authors.lastname: Muhammad Hafiz
authors.affiliation: Nanoelectronics Lab, MIMOS Berhad, Technology Park Malaysia, Kuala Lumpur 57000, Malaysia.
authors.forename: Khairul Anuar Abd
authors.initials: KA
authors.lastname: Wahid
authors.affiliation: Nanoelectronics Lab, MIMOS Berhad, Technology Park Malaysia, Kuala Lumpur 57000, Malaysia.
authors.forename: Zulkarnain
authors.initials: Z
authors.lastname: Endut
authors.affiliation: Nanoelectronics Lab, MIMOS Berhad, Technology Park Malaysia, Kuala Lumpur 57000, Malaysia.
authors.forename: Hing
authors.initials: H
authors.lastname: Wah Lee
authors.affiliation: Nanoelectronics Lab, MIMOS Berhad, Technology Park Malaysia, Kuala Lumpur 57000, Malaysia.
authors.forename: Daniel C S
authors.initials: DC
authors.lastname: Bien
authors.affiliation: Mechanical Section, Universiti Kuala Lumpur Malaysian Spanish Institute, Kulim Hi-TechPark, Kedah 09000, Malaysia.
authors.forename: Ishak
authors.initials: I
authors.lastname: Abdul Azid
authors.affiliation: School of Mechanical Engineering, USM Engineering Campus, Universiti Sains Malaysia, Nibong Tebal, Pulau Pinang 14300, Malaysia.
authors.forename: Mohd Zulkifly
authors.initials: MZ
authors.lastname: Abdullah
authors.affiliation: Low Dimensional Materials Research Centre, Physics Department, Faculty of Science, University of Malaya, Kuala Lumpur 50603, Malaysia.
authors.forename: Nay
authors.initials: N
authors.lastname: Ming Huang
authors.affiliation: Low Dimensional Materials Research Centre, Physics Department, Faculty of Science, University of Malaya, Kuala Lumpur 50603, Malaysia.
authors.forename: Saadah
authors.initials: S
authors.lastname: Abdul Rahman