Preparation and Characterization of Metal Phthalocyanine Films for Device Application

Abstract

Organic semiconductors have attracted much attention because of their light weight, newlineflexibility and non fragility. Organic materials have a long storage life and high read out newlinetimes for use in optical storage systems. Their interesting physical properties combined newlinewith low cost, make this particular family of organic semiconductors suitable for the newlinedevelopment of novel electronic devices. Organic materials are widely used for room newlinetemperature sensing due to their specific semiconducting and optical properties. From the newlineclasses of organic materials, the metallic phthalocyanines (MPc s) are known for their newlinesemiconducting properties with high environmental, thermal stability, good molecularelectronic newlinetunabilty and also with high absorption coefficient and have numerous newlineapplications like photoconducting agent, nonlinear optics, chemical sensors and electro newlinecatalysis etc. Mostly metal phthalocyanines are p-type semiconductors and are stable newlinetowards chemicals and heat. Among Metallo phthalocyanines, copper phthalocyanine newline(CuPc) and zinc phthalocyanine (ZnPc) are important organic materials with a high newlineabsorption coefficient, good photochemical and thermal stabilities. Their electrical newlineconductivity changes by the adsorption of oxidized or reduced organic vapors or gaseous newlinespecies on thin films, which make them suitable material for vapor sensors, photovoltaic newlineapplications and opto electronic devices. CuPc and ZnPc based thin films are used as newlinevapor sensors at a large scale for the detection of various toxic vapors like, NH3, NO2, newlineNO, Cl2, alcohols, amines etc. Sensing characteristics of MPc based thin films depend on newlinefilm morphology, substrate temperature, sensing temperature, nature of substrate, newlineannealing temperature and period of annealing. Therefore, a complete analysis of newlinematerials properties is required for the preparation of an efficient device. So, aim of newlinepresent work is to determine the charge transport properties and to prepare low cost metal newlinephthalocyanine based room temperature vapors sensors for the detection of ammonia newlinevapors. newline