Metal Carbon Nanotube Schottky Barrier Diode with Detection of Polar Non-Polar Gases

In Metal-Carbon Nanotube ( CNT) interfaced devices, carrier transport is mainly controlled by the Metal-CNT junction. In our study we made a half-emerged interaction of metals ( like Gold, Palladium and Platinum) with CNT and found that it creates a rectifying schottky barrier junction. The schottky barrier height has been measured using two different approaches that is Band modeling technique and the Activation energy method. The different characteristics on making the Metal-CNT-Metal contact like dipole formation, Partial Device Density of states ( PDDOS), Electrostatic Difference Potential and I-V characteristics has been measured and analyzed to understand the device behavior. Further we have used ( 10, 0) Zigzag CNT as a gas sensing device, the gases taken are of polar ( NO2), as well as non-polar ( N-2) type. The change in conductivity of the device, before and after the gas adsorption can be used in order to detect the particular gas molecule. The point of maxima at zero bias in conductivity curve are different for different gas molecule however on increasing the number of gas molecules the point of maxima remains the same but it is slope becomes steeper and steeper. Also the maximum conductivity depends on both the nature of gas as well as on the amount of gas and is maximum for NO2.