| 摘要 |
<p>PURPOSE:To extinguish shottky barrier between a sintered substance and a metallic electrode so as to make it excellent in mechanical strength and surge resistance by providing a contact layer, consisting of a specific zinc oxide, between the sintered substance and the metallic electrode. CONSTITUTION:Proper amounts of Pr, Co, B, etc., in the form of compounds such as oxides, etc., are added to ZnO powder, and then are mixed and granulated so as to make up granulated powder for ZnO varistor, and this granulated powder is formed into disc shape. Next, solution, wherein nitric acid indium In(No3).-9H2O is dissolved in acetylacetone, is applied on opposing both main faces of a sintered substance 3 which is made by firing, and is heat-treated after drying so as to disperse In into a ZnO sintered substance. Since the contact layers 2A and 2B, wherein In is introduced into zinc oxides, are low resistant layers, schottky barrier between the zinc oxides and the metallic electrodes 1A and 1B disappears, and mechanical strength and surge resistance become favorable.</p> |
