| 摘要 |
PURPOSE:To improve the reliability and production yield of a semiconductor device such as a power transistor module by a method wherein the belt-shaped portions where the thicknesses of the plates are thinner are provided along the circumferences of element mounting pads, wire bonding pads and bonding metal plates. CONSTITUTION:A 98% alumina plate of 0.635mm thickness is used as an insulating plate 33. Wire bonding pads 23 and chip mounting pads 24 formed on one main surface of the insulating plate 33 and bonding metal plates 25 formed on the other main surface of the insulating plate 33 are composed of tough-pitch copper plates. Steps are formed on the upper surfaces of the circumference portions of the metal plates such as the pads 23 and 24 and the bonding metal plates 25 and the plated thicknesses along those portions are formed to be as thin as 0.1mm. With this constitution, contraction forces of a group of the metal plates are reduced so that cleaving and cracking of the insulating plate can be avoided. If a semiconductor device is formed by employing the substrate like this, the yield and reliability of the products can be improved. |
