Abstract
        In the present work, we have investigated the capacitive hygrometers fabricated by polymer, cellulose, using different 
electrodes. Polymer films were deposited by two different deposition methods: spin coater method and by placing the drop 
of cellulose suspension in distilled water on primarily deposited electrodes. The DC and AC (at frequency of 20 Hz) 
capacitances of the samples were evaluated in the relative humidity range of 30-90%. It was observed that the capacitance 
of the cellulose increases with increase in relative humidity level. Comparison of two different methods shows that the drop 
coasted films were more sensitive than the spin coated ones where as the response and recovery time of spin coated 
samples was much shorter than the drop coasted samples. The relative capacitance ratio to the relative humidity was found 
1.5 and 7 for samples deposited by spin coating and drop method, respectively. Humidity dependent capacitive behavior of 
cellulose made it attractive for the development of humidity meter.
        Keywords
        Capacitive hygrometers, Cellulose, Drop method, Relative humidity level.
        Citation
        ZUBAIR AHMAD, MUHAMMAD H. SAYYAD, KHASAN. S. KARIMOV, Capacitive hygrometers based on natural organic  compound, Optoelectronics and Advanced Materials - Rapid Communications, 2, 8, August 2008, pp.507-510 (2008).
        Submitted at: June 4, 2008
 
        Accepted at: July 16, 2008