Preparation And Characterization Of Nano-magnesium Oxide Film For Biosensor

In the1960s, the concept of Biosensor was first proposed, which has a high degree of selective, high sensitivity, fast response, low sample consumption, small size, high accuracy, etc. With the development of society biosensor occupy an increasingly important position in the Bioanalytical techniques. With the raising level of science and technology, the gate dielectric of transducer of biosensor has been unable to adapt to the needs of the development. Accordingly, a new nano-film should be prepared to instead of SiO2. MgO with a high dielectric constant, good insulating properties, low cost and simple to be prepared has become possible alternative SiO2. The main contents are as follows:1. The limitations of nano-film SiO2as gate dielectric of transducer of biosensor are summarized. With thinning of the SiO2film, it will cause the drain current increases and uneven oxide, these deficiencies will result in performance degradation of the MOSEFT. The new requirements of high-dielectric constant material were suggested.2. The magnetron sputtering is an important method for preparing nano-MgO film, but the uniformity of film is limited the applications. In this paper, a model of target molecule’s motion the process of magnetron sputtering was created, a equation of the film thickness distribution on the substrate was obtained by derivation, it is was verified by experiments.3. On silicon substrate, nano-MgO films were prepared by magnetron sputtering and its transmittance and XRD were characterized. A new method of measuring the dielectric constant was discovered. A MOS transistor structure was constructed, the C-F curves were obtained, the dielectric constant and equivalent thickness of low frequency were calculated by fitting the curves.