| 摘要 |
<p>PURPOSE:To obtain excellent overload characteristics even on a low thermal conductive substrate by a method wherein the range of a trimming trench to be formed into a resistor layer is limited within a specific distance from one upper surface electrode. CONSTITUTION:A pair of surface electrodes 2 of a silver base film on an insulating substrate 1 such as glass alumina ceramics, etc., a resistor layer 3 of a ruthenium-based thick film overlapped with a part of the upper surface electrode 2, a trimming trench 6 to adjust resistance value to a desired value are formed in the resistor layer 3. Furthermore, a glass layer 5 completely covering the resistor layer 3, a pair of side electrode layers 4 overlapped with a part of the upper electrodes 2 as well as an Ni plated layer and a solder plated later are formed on the exposed electrode surface. At this time, the trimming trench 6 is formed within the range not exceeding 1/3 of the interval between one surface electrode layer 2 and the other surface electrode layer 2. Trough these procedures, excellent overload characteristics can be displayed even if a glass alumina ceramic substrate in a low thermal conductivity is used.</p> |
