| 摘要 |
<p>PURPOSE:To make it possible to prevent scorching of a printed board by a method wherein the title chip resistor is composed of the upper electrode layer of silver thin film formed on a porous ceramic substrate, a resistance layer of ruthenium thick film, an overcoating glass layer, and an edge electrode layer of silver thick film which is overlapped on a part of the upper electrode layer. CONSTITUTION:A porous ceramic substrate 1 is used as a base material, alumina silica glass is used as an undercoat glass layer 2, a silver thick film electrode is used as a top electrode layer 3 and an edge face electrode layer 6, and the ruthenium thick film resistor, which is partially overlapping on the top surface electrode layer 3, is used as a resistor 4. Lead borosilicate glass, with which the resistor layer is covered, is used as an overcoating glass layer 5, and these layers are formed by conducting coating and screen printing operations. Lastly, an Ni-plated layer 7 and an Sn-Pb plated layer 8 are formed by conducting an electrolytic plating operation on the exposed part of the edge face electrode layer 6, and the title resist or is completed. As a result, the heat generated on the resistance layer 4 is not transmitted to the porous ceramic board 1, and as the heat is dispersed through the terminal part, scorching of the printed board can be prevented.</p> |
