Nano-sized MgO Film Preparation And Research Of Parameter Influence On The Deposition

There are varieties of methods to detect the existence of a substance in a biological sample, determine the ingredients, detect the change of component content, and characterize the constituent structure. The biosensor has been widely applied in medicine, biological engineering, food industry and environmental pollution detection because of its high selectivity, high sensitivity, fast response, low sample consumption, small volume and high accuracy.The traditional gate dielectric material of transducer of biosensor is SiO2. But with the development of biosensors, the equivalent thickness of insulated gate dielectric layer has been reduced to nanoscale. Thin SiO2 used for gate dielectric will reduce the stability and reliability of the transducer. However nano-sized MgO film with good insulation properties, high dielectric constant, low prices and a variety of preparation methods has the possibility to replace SiO2. The main research content includes:1、Nano-sized MgO films were prepared on Si substrate by magnetron sputtering. The thickness of MgO films were measured by using SGC-10 film thickness gauge.2、Theoretical model was established to describe the thickness distribution of the MgO film prepared by magnetron sputtering method. The film thickness distribution equation was deduced, and discrete values were used to simulate the distribution of thickness. At the same time the actual distribution of the thickness was fitted.We found it agrees well with the theoretical model. The results show that the thickness distribution of MgO film prepared by magnetron sputtering method is not completely uniform. The thickness of the film expresses the descended distribution trend from the center to the periphery.3、The influences of preparation parameters (such as sputtering power, flow of argon, target-substrate distance, substrate temperature, high sputtering pressure) on the film deposition rate was studied by theory. Then the sputtering pressure and substrate temperature were changed respectively to prepare MgO films. The deposition rates of different samples were calculated. Results show that when the sputtering pressure increases, the deposition rate declines. The effect of substrate temperature on the deposition rate is not obvious. The results provide excellent references for the preparation of MgO film by magnetron sputtering method.