Low thermal resistant, fluid-cooled semiconductor module

Abstract

Semiconductor devices are fixed on a substrate by solder and a semiconductor module having an enclosed structure is formed by the substrate, flanges and a housing. Two groups of heat conducting members, each having fins respectively in contract with the semiconductor devices and an inner wall of the housing are attached to the semiconductors. A fin thickness of each fin of the two groups of heat conducting members is comparatively thick, a fin height is low and the respective fins of the respective opposed heat conducting members have with very small clearances therebetween. A liquid as a heat conducting medium is enclosed in the semiconductor module. The liquid level of the semiconductor module is controlled such that it contacts a uppermost semiconductor device in the semiconductor module in a vertical arrangement. Further, valve mechanisms for introducing and removing a cooling fluid are provided at a top face and a bottom face of a space formed in the semiconductor module. The mass production capability of the heat conducting members is improved by providing such highly rigid fins, and improved cooling function is provided by firmly introducing the cooling medium to the respective fins while permitting the module to be reduced in size.