The invention relates to a semiconductor device and more particularly to a device comprising a casing support and a carrier member for a semiconductor member, the latter also being soldered onto the carrier member which is a good conductor of heat and is applied to the casing support with the aid of solder.
In order to achieve good dissipation of heat, particularly in power semiconductor components, a carrier member comprising a material which is a good conductor of heat has in the past been inserted between a metallic casing support and the semiconductor body. These carrier members comprise copper for example. In prior arrangement a soldered disc is placed onto the casing support, for example a TO-3 support. A copper disc for example, forming the carrier member is then placed onto the soldered disc. A second soldered disc is applied to the copper member. This arrangement is then placed in a solder furnace in which the solder melts at a relatively high soldering temperature and connects the carrier member to the casing support. After this soldering process, which takes place for example at 500.degree. C., the surface of the carrier member which is now moistened by solder is brushed off and possibly subjected to further cleaning processes. The semiconductor member is then placed onto the upper surface of the carrier member which is coated with the solder and the arrangement is subjected to a second soldering process in which the semiconductor member is firmly connected to the carrier member. In order to avoid damage to the semiconductor member or the semiconductor component contained therein this second solder temperature is relatively low. For example if may be 400.degree. C.
The method described has the disadvantage that two soldering processes are required, these being carrier out at different soldering temperatures and cleaning procedures have to be carried out between the soldering processes.
USPTO Backgrounds
USPTO Backgrounds