Esd protection structure and method for manufacturing the same

Abstract

An ESD protection device includes an alumina multilayer substrate, a hollow portion, a discharge electrode pair, discharge-assisting electrodes, and a vitreous substance. The hollow portion is disposed inside of the alumina multilayer substrate. The electrodes of the discharge electrode pair are disposed opposite to each other at an interface between the hollow portion and the alumina multilayer substrate. The discharge-assisting electrodes are disposed dispersedly between the opposite electrodes of the discharge electrode pair. The vitreous substance covers the discharge-assisting electrodes in the inside of the hollow portion. A trial discharge is executed so as to induce creepage discharge between the electrodes of the discharge electrode pair in advance.

What is claimed is: 
     
         1 . An ESD protection structure comprising:
 an insulating portion;   a pair of discharge electrodes disposed at a distance from each other on a surface of the insulating portion;   discharge-assisting electrodes disposed between the pair of discharge electrodes and including insulating material-coated metal particles and/or semiconductor particles; and   a vitreous substance disposed around the discharge-assisting electrodes to embed the discharge-assisting electrodes in the vitreous substance; wherein   discharge craters, at which the discharge-assisting electrodes are exposed, are disposed in the vitreous substance and defined by a removed portion of the vitreous substance.   
     
     
         2 . The ESD protection structure according to  claim 1 , further comprising a hollow portion disposed adjoining the surface of the insulating portion is further included. 
     
     
         3 . The ESD protection structure according to  claim 1 , wherein the insulating material-coated metal particles are alumina-coated Cu particles and the semiconductor particles are SiC particles provided with oxide films. 
     
     
         4 . The ESD protection structure according to  claim 1 , wherein the insulating portion is an alumina multilayer substrate. 
     
     
         5 . The ESD protection structure according to  claim 1 , wherein the particles of the discharge-assisting electrodes have different particle diameters.