| 摘要 |
PURPOSE:To prevent packages located near to a package provided with a heat sink from deteriorating in cooling efficiency by a method wherein fins are provided to a support as tilted, and the angle of inclination of the upper fins is set larger than that of the lower fins. CONSTITUTION:A cap 6 is bonded to the upside of a ceramic board 1 with an adhesive agent of low-melting glass or the like so as to cover a chip 2, and the chip 2 is hermetically sealed up with the cap 6. An aluminum heat sink is bonded to the upside of the cap 6 with a heat sink fixing agent. The heat sink 7 is composed of many planar fins 7b, 7b,... mounted on a support 7a as vertically arranged, and the angles of inclination of the fins 7a to a horizontal plane are so set as to become gradually larger with the distance from the cap 6 to the fins 7a. Therefore, air is made to flow downward through a heat sink toward packages 9a and 9b located on the rear, so that a boundary layer region located on the surface of the packages 9a and 9b becomes thin, and the packages 9a and 9b can be improved in cooling efficiency. |
