A kind of varistor and its manufacturing process

Abstract

The invention relates to a piezoresistor and a manufacturing process thereof. The piezoresistor is composed of a ceramic substrate, a leading-out end, an electrode layer and an insulating layer, wherein a concave area, namely, an electrode positioning area, is prefabricated on the ceramic substrate; the leading-out end is arranged on an electrode; the insulating layer is used for locally or wholly packaging the ceramic substrate, the electrode layer and the leading-out end; in the manner of sputtering or spraying electrode, an electrode hole of a mask plate is positioned and coated on a concave opening; a small electrode hole and a big concave opening form a bottle-shaped structure; the electrode is drifted and deposited into the concave opening so as to form the electrode and realize the concave opening being accurately filled with the electrode; the electrode eccentricity caused by the difference in diameter of the ceramic substrate in a batch sputtering process can be avoided; the thickness of the ceramic substrate at an edge of the concave opening is greater than the thickness of the interior; the reducing of the risk in edge arc crossing is benefited; the edge effect is weakened; the flowing property is greatly promoted; the preparation process of the piezoresistor comprises the following steps: manufacturing the ceramic substrate, performing electric polarization, connecting the leading-out end, coating the insulating layer, printing and testing.

Description

technical field [0001] The invention relates to the field of varistor manufacturing, in particular to a varistor for synchronously prefabricating concave electrode regions in a molding process and a manufacturing process. Background technique [0002] Due to its good voltage limiting characteristics, varistors are widely used from weak current systems to strong current systems, from electrostatic protection, SPD valve plates to arresters, from line surge protection to motor demagnetization energy absorption. When the suppression voltage is turned on, it is close to a short circuit, so the overlapping size of the double electrodes is similar to the wire diameter, which directly determines the current capacity of the product. [0003] Considering that the electrode thickness affects the current diffusion and current carrying capacity, the surface metallization methods commonly used in electronic ceramics, electroplating and evaporation, are not suitable for large current impac...

AI Technical Summary

Problems solved by technology

[0005] The eccentricity of the electrodes not only leads to a decrease in the flow capacity of the piezoresistor, but also tends to cause side flashes. In severe cases, the electrodes even shift to the side of the ceramic substrate and are directly connected

Images