PURPOSE: To obtain sufficient cooling effect without giving concentrated stress by a method wherein the bottom face of the bag type container with sealed liquid type refrigerant is partially formed by the material which can be formed into a rigid body, and the rigid part is contacted to the back side of chips.
CONSTITUTION: Small plates 7a, which were hardened by mixing Al powder with Si rubber, are arranged on a rest D, the clearance between the plates is buried by pouring Si rubber into it, the plates are peeled off the rest D after hardening, they are pressed to the prescribed thickness, and a film 5b is formed. Si rubber film 5a is superposed on the above, and the bag type container 5 is formed by adhering the circumference, and a copper pipe 8 is arranged in such a manner that it makes a zigzag line in the bag. The circumference of the bag 5 is pinched between Al frames 11 and 12, tightened by a bolt 13 and the bag 5 is covered from above a substrate 1. When a proper quantity of pure water 6 is poured 10 into the bag and the bag is maintained in a freely transformable state, the bag 5 hangs down due to the weight of the pure water, the rigid body 7 comes in contact with the corresponding chips 2 lightly and uniformly under the prescribed pressure without allowing the generation of transformation and the concentrated stress. Also, since the thermal resistance can be maintained at a sufficiently low level, a satisfactory cooling effect can be obtained without characteristic deterioration and breakdown on the semiconductor device.
HIROTA KAZUO
ISHI ICHIROU
WATANABE YUTAKA
