title: A humidity sensing organic-inorganic composite for environmental monitoring.
abstract: In this paper, we present the effect of varying humidity levels on the electrical parameters and the multi frequency response of the electrical parameters of an organic-inorganic composite (PEPC+NiPc+Cu2O)-based humidity sensor. Silver thin films (thickness ~200 nm) were primarily deposited on plasma cleaned glass substrates by the physical vapor deposition (PVD) technique. A pair of rectangular silver electrodes was formed by patterning silver film through standard optical lithography technique. An active layer of organic-inorganic composite for humidity sensing was later spun coated to cover the separation between the silver electrodes. The electrical characterization of the sensor was performed as a function of relative humidity levels and frequency of the AC input signal. The sensor showed reversible changes in its capacitance with variations in humidity level. The maximum sensitivity ~31.6 pF/%RH at 100 Hz in capacitive mode of operation has been attained. The aim of this study was to increase the sensitivity of the previously reported humidity sensors using PEPC and NiPc, which has been successfully achieved.
authors.affiliation: Low Dimensional Materials Research Centre, Department of Physics, University of Malaya, Kuala Lumpur 50603, Malaysia. zubairtarar@um.edu.my
authors.forename: Zubair
authors.initials: Z
authors.lastname: Ahmad
authors.forename: Qayyum
authors.initials: Q
authors.lastname: Zafar
authors.forename: Khaulah
authors.initials: K
authors.lastname: Sulaiman
authors.forename: Rizwan
authors.initials: R
authors.lastname: Akram
authors.forename: Khasan S
authors.initials: KS
authors.lastname: Karimov
mesh_terms: D003300:Copper / Q000737:chemistry; D004566:Electrodes; D004784:Environmental Monitoring / Q000295:instrumentation* / Q000379:methods; D006801:Humans; D006813:Humidity; D008855:Microscopy, Electron, Scanning; D009942:Organometallic Compounds / Q000737:chemistry; D012834:Silver / Q000737:chemistry*
chemical_list: D009942:Organometallic Compounds; C488300:nickel phthalocyanine tetrasulfonate; D012834:Silver; D003300:Copper; C000520:cuprous oxide