Semiconductor Device

摘要

1,168,554. Semi-conductor devices &c. ALLMANNA SVENSKA ELEKTRISKA A.B. 22 Feb., 1967 [23 Feb., 1966], No. 8432/67. Heading H1K. A semi-conductor device comprises a unit consisting of a semi-conductor body with or without associated electrode assemblies, mounted between terminal bodies at least one of which is in pressure contact with the unit. At least one of these bodies is connected to or forms part of a cooling body comprising a stack of spaced apart resilient plates. The plates extend laterally beyond the unit and clamping means for providing the pressure contact are disposed on the laterally extending parts. In a typical example the device is a silicon controlled rectifier consisting of a PNP disc soldered between molybdenum plates with aluminium and goldantimony alloy respectively. The disc is mounted between dished plates silver soldered at their periphery to ceramic rings, which are likewise soldered, to metal rings which are subsequently joined by cold welding or solder to form a sealed housing, from which the control electrode extends between the rings. The housing 13 (Fig. 1) is held between bosses formed on members 14, 15, which are bolted and riveted to resilient cooling plates held apart by spacers 24, the outermost plates being bent over to channel cooling air between the other plates. Members 14, 15 may be formed integral with the innermost cooling plates. The assembly is clamped together by a pair of bolts extending through each set of cooling plates and engaging nuts built into insulating bodies disposed between the sets of plates. In an alternative form in which the lower set of plates is omitted member 14 is extended laterally to accommodate the clamping bolts. In a simplified arrangement in which the housing contains a diode (Fig. 5, not shown) the bosses form the terminal parts of centrally disposed rivets holding the cooling plates together. In this case the plates in each set extend alternately mainly to left and right of the rivets with the overlapping sections acting to space the plates apart. Suitable materials for the spacers, plates and boss members are copper, aluminium and silumin. It is stated that the sealed devices may alternatively comprise germanium or silicon bodies with deposited electrodes of gold, silver, copper, aluminium, nickel, chromium, molybdenum, lead or alloys thereof, or disposed between electrode plates of fernico, tungsten or molybdenum.