TY - CONF AV - none CY - Kuala Lumpur ID - scholars2537 SP - 648 TI - Preparation of the spacer for narrow electrode gap configuration in ionization-based gas sensor N2 - Carbon nanotubes (CNTs) have started to be developed as the sensing element for ionization-based gas sensors due to the demand for improved sensitivity, selectivity, stability and other sensing properties beyond what can be offered by the conventional ones. Although these limitations have been overcome, the problems still remain with the conventional ionization-based gas sensors in that they are bulky and operating with large breakdown voltage and high temperature. Recent studies have shown that the breakdown voltage can be reduced by using nanostructured electrodes and narrow electrode gap. Nanostructured electrode in the form of aligned CNTs array with evenly distributed nanotips can enhance the linear electric field significantly. The later is attributed to the shorter conductivity path through narrow electrode gap. The paper presents the study on the design consideration in order to realize ionization based gas sensor using aligned carbon nanotubes array in an optimum sensor configuration with narrow electrode gap. Several deposition techniques were studied to deposit the spacer, the key component that can control the electrode gap. Plasma spray deposition, electron beam deposition and dry oxidation method were employed to obtain minimum film thickness around 32 μm. For plasma spray method, sand blasting process is required in order to produce rough surface for strong bonding of the deposited film onto the surface. Film thickness, typically about 39 μm can be obtained. For the electron beam deposition and dry oxidation, the film thickness is in the range of nanometers and thus unsuitable to produce the spacer. The deposited multilayer film consisting of copper, alumina and ferum on which CNTs array will be grown was found to be removed during the etching process. This is attributed to the high etching rate on the thin film which can be prevented by reducing the rate and having a thicker conductive copper film. © 2012 American Institute of Physics. N1 - cited By 0; Conference of 2nd International Conference on Fundamental and Applied Sciences 2012, ICFAS 2012 ; Conference Date: 12 June 2012 Through 14 June 2012 SN - 0094243X Y1 - 2012/// EP - 654 VL - 1482 A1 - Saheed, M.S.M. A1 - Mohamed, N.M. A1 - Burhanudin, Z.A. UR - https://www.scopus.com/inward/record.uri?eid=2-s2.0-84874176331&doi=10.1063%2f1.4757551&partnerID=40&md5=fde41faf888096d42dad20d23df15986 ER -