Improvements in or relating to semi-conductor devices

摘要

834,000. Semi-conductor devices. SIEMENSSCHUCKERTWERKE A.G. April 30, 1956 [April 30, 1955], No. 13285/56. Class 37. A PN junction element is disposed in a gastight housing comprising a rigid base-plate, an inner surface of which is provided with a dished portion accommodating the element, and a cap portion, the rim of which is sealed in an endless groove formed in the base-plate surrounding the dished portion. The cap portion includes two spaced coaxial shells rigidly joined by an insulating ring, and accommodates a spring bearing at opposite ends on the cap portion-and the junction element respectively. In the embodiment shown in Fig. 1 a silicon wafer 3 containing a PN junction or a stack of such wafers is soldered between a recess 2 in a base member 1 and the top of a bell-shaped spring 6 located by solder in the dished part of cap 5. The cap is formed of two parts 5a and 8 electrically insulated from one another by a fused glass seal 8. The rim of cap 5 is sealed into an annular groove and in the base-plate by solder or by a thermoplastic or casting resin. To facilitate transfer of heat to a mounting the lower face of the base-plate is serrated and engages with corresponding serrations on the mounting. A conductor 9 is soldered in a recess in the base of the cap. Alternatively an externally-threaded tubular conductor serving also as an exhausting tubule may be formed as an integral extension of the base of the cap by pressing or casting. In a further embodiment (Fig. 3) the cap comprises a recessed plate formed with a conducting stub 14 and an integral cylindrical part 16, 17. The rim of part 17 is soldered as before into a recess in the baseplate 11. The devices may be made by pretinning all the surfaces to be soldered, forming a sub-assembly comprising the cap and spring, placing the sub-assembly over the base-plate and rectifier element, and heating to form the solder joints. The device is then evacuated or filled with a protective fluid such as hydrocarbon oil, nitrogen, hydrogen or carbon dioxide.