Studies On The Transport Behavior And Mechanism Of Metal Organic Bi-layer Thin Film

Elementary transport behavior is one of the basic characters of material. It is involved in many fields, including electrical device manufacture, reliability and failure analysis. In recent years, metal organic complex thin films are widely used in many fields such as organic luminescence, ultra high density storage film, nanoelectronics devices and so on. Therefore the transport behavior between metal and organic film is a remarkable topic. To clarify the law of transport in thin film will have great impact on both science and practice.In this paper, two kinds of material with different electrical affinity (Ag and TCNQ) are chosen and prepared to bi-layer film. The transport behavior of this system is studied experimentally and theoretically. Special phenomena and rules are revealed and the mechanism of transport process is discussed. All results can be a useful guidance to fast preparation of the relevant films and failure analysis. The main findings are as follow-ups:1. Ag/TCNQ bi-layer thin film with good stoichiometry and stable electrical character is obtained by alternately vacuum deposition.2. The transport behavior in Ag/TCNQ bi-layer film is studied through solid state chemical diffusion reaction by using transmission spectrum to monitor the process. An anomalously fast transport phenomenon is observed when the film is ultra thin.3. Tunneling model and non-tunneling model are established respectively based on the field induced migration theory. Results from theoretical analyses indicate that the transport process accords with parabola when the film is relatively thick, while matches inverse logarithm when the film is ultra thin.4. The transport process of Ag/TCNQ bi-layer under different humidity condition is studied carefully. It is found that environmental humidity can greatly accelerated the transport process. A mechanism of electrochemistry is proposed to explain this phenomenon. An inverse proportional relationship between transportspeed and humidity is found out. A humidity controlled transport model is proposed based on surface adsorption theory.5. The equivalent pore radius of Ag-TCNQ is deduced to be 15 (?) based on capillary condensation theory, which does not vary with film thickness.6. A new method by combining vacuum deposition and electrochemical reaction is developed to prepare metal-organic thin films. Ag-TCNQ film which is prepared by this method shows an electrical bistable characteristic with good homogeneity. It also has a smooth surface morphology and a stoichiometric composition. This new method is helpful to make micro-electronics devices, molectroics devices and high density memories.