Method for improving electrical property of zinc-oxide-based low voltage varister ceramic film

Abstract

The invention relates to varistor ceramics, and specifically relates to a method for improving the electrical property of a zinc-oxide-based low voltage varister ceramic film. The method is characterized in that: an aluminum foil, which is used as an absorption layer, is attached to the surface of a zinc-oxide-based low voltage varister ceramic film sample; a confinement medium is painted, stuck or covered on the aluminum foil; the ceramic film sample is then embedded on a mold; and laser impact is applied to the ceramic film sample, such that the electrical property of the zinc-oxide-based low voltage varister ceramic film is improved. According to the present invention, a laser impact treatment technology is employed in the surface treatment upon the zinc-oxide-based low voltage varister ceramic film. With the liquid confinement medium, non-linear coefficient of the zinc-oxide-based ceramic film is raised by 24% or above comparing to that before the laser impact treatment, varister voltage of the zinc-oxide-based ceramic film is reduced by 30% or above comparing to that before the laser impact treatment, and leakage current density of the zinc-oxide-based ceramic film is reducedby 35% or above comparing to that before the laser impact treatment. The advantage of the method is that: non-linear coefficient of the film is improved while the leakage current density of the film is reduced.

Description

technical field [0001] The invention relates to pressure-sensitive ceramics, in particular to a method for improving the electrical properties of zinc oxide-based low-voltage pressure-sensitive ceramic thin films. Background technique [0002] Laser Shock Processing (LSP) is a high power density (10 9 W / cm 2 ), short pulse (ns-level) laser irradiates the material, the additional coating on the surface of the material is rapidly vaporized to form a plasma expansion explosion to generate a high-pressure shock wave, which changes the microstructure or physical properties of the material, thereby changing the properties of the material. A new type of surface treatment technology. [0003] At present, laser shock treatment technology is used in the surface strengthening treatment of metal materials, such as various types of industrial steel, non-ferrous metal alloys and other fields, mainly to improve the mechanical properties of materials such as hardness, corrosion resistance...

AI Technical Summary

Problems solved by technology

[0004] For example, ZnO varistor has the advantages of excellent non-ohmic characteristics, small leakage current, large flow capacity, fast response time, and low cost. It is an ideal device for suppressing instantaneous high voltage and absorbing surge energy, and can be widely used in various In electrical equipment and electronic systems; in recent years, with the development of electronic products in the direction of miniaturization, thinning, integration and multi-function, it is required to lower the voltage of varistors. At present, the main method of preparing ZnO low voltage varistors is The methods include: wafer-type low-voltage varistors by controlling the growth of ZnO grains; multi-layer laminated low-voltage varistors using chip component preparation technology; ZnO low-voltage varistors using thin-film preparation technology; ZnO ceramics The thickness of the film is extremely small and can be adjusted between hundreds of nanometers and several microns, so it has very good potential and advantages in the preparation of low-power varistors with a varistor voltage lower than 5V. The thickness of the zinc oxide-based ceramic film is reduced At the same time, the varistor voltage is reduced, but the nonlinear coefficient is also reduced. When studying ZnO low-voltage varistor ceramics, in order to obtain a high nonlinear coefficient while reducing the varistor voltage, the researchers optimized the material group A lot of research work has been carried out in the aspects of element and component design and preparation and processing methods, and many scientific research results have been obtained, but the effect is not satisfactory.