| 摘要 |
1,062,985. Semi-conductor devices. MOTOROLA Inc. Jan. 10, 1966 ]Feb. 17, 1965], No. 1066/66. Heading H1K. A transistor is mounted in a package comprising a major housing structure by inserting a thermally conductive electrically insulative spacer between the collector electrode and the major housing structure and electrically connecting one of the other electrodes to the major structure. The device is used in high frequency high power circuits, and a low impedance connection to the " common " circuit electrode (base or emitter) is provided by the electrical connection to the housing, thus reducing the degeneration and increasing the gain. As shown, Fig. 2, a transistor die 26 is soldered to copper collector electrode 24 which is thermally connected to, but electrically insulated from, the major structure 12 of the housing by a spacer (22), Figs. 1 and 4 (not shown), of beryllia or alumina to which it is soldered. Collector electrode 24 is also soldered to an insulated lead-out wire 14. A base electrode 28 is soldered to an insulated lead-out wire 16 and is connected to the base region 29 of the transistor by a plurality of fine wires 30. The emitter regions 35 of the transistor are connected by a plurality of fine wires 34, 36 to two conductive bars 31, 32 connected to the major structure 12. The base and emitter connections may be effected by conductive ribbons instead of a plurality of wires. The housing is completed by attaching a cover (11) to the major structure (12), Fig. 1 (not shown). The device may be used in common emitter circuits but a device suitable for common base circuits may be produced by connecting the base region to the bars (31), (32) and the emitter regions to the insulated lead out wire (15), Fig. 5 (not shown). In an alternative package, Fig. 7, thermally conductive electrically insulative spacer 52 is mounted on a copper stud 50 and surrounded by a ceramic ring 54. A collector electrode 56 comprising a ring portion, an external lead portion and an inwardly extending tab portion, Fig. 8 (not shown), is bonded to ring 54 and the tab is bonded to spacer 52. Transistor die 58 is bonded to the tab of electrode 56. A metal cup 60 is bonded to stud 50 and short wires 62 are connected between emitter region (59), Fig. 6 (not shown), and cup 60. A ceramic ring 64 is bonded to electrode 56 and base electrode 66 is bonded to this ring and connected to base region (67) by wires 68. The encapsulation is completed by a ceramic ring 70, cap retainer 72 and cap 74. The base and emitter connections may also be intercharged in this embodiment. |
