GB1376940A - Panel board circuit systems - Google Patents

Abstract

1376940 Semi-conductor devices; Printed circuit component assemblies TEXAS INSTRUMENTS Inc 26 Nov 1971 [10 Dec 1970] 58581/73 Divided out of 1376939 Headings H1K and H1R An integrated circuit device comprises a rigid dielectric, e.g. ceramic card 12, on which is a metal pad 14 and plural conductive printed circuit paths 16 extending from locations peripheral of the pad to spaced contacts along edge 12.1; an integrated circuit chip 18 of Si being mounted on pad 14 with leads 20 interconnecting its terminals 22 to paths 16. The cards may be pressed of Al or Be oxide powder mixed with epoxy binder and baked; after which a surface is masked to define pad 14 and paths 16 which are formed by a liquid suspension of conductive W metal; and the card is again baked to remove the mask and produce adherent metal coatings at, e.g. 14.1, 16.1. A liquid glaze 24 is applied to the surface leaving pad 14 and the ends of paths 16 exposed, and a ceramic ring 26 with annular W coating 26.1 is applied to the glaze to surround pad 14 and the adjacent ends of paths 16. Further baking affixes the ring and hardens the glaze, after which a noble metal is electrolessly plated on pad 14, the ring 26, and the ends of the paths at e.g. 14.2, 16.2, 26.2. The chip 18 is affixed to the pad, and its lead wires connected thereto and to the ends of paths 16 by thermocompression bonding; while a metal cover 28 is similarly sealedly attached to plating 26.2 of the ring 26 (Figs. 1, 2). Connectors 30 of a mounting (Fig. 4), are formed of halves 32, 34, of e.g. glass reinforced nylon, bonded together to define a recess 36 and to secure connector contacts 38, 40 in alternate spaced relation thereon. Half 32 has plural grooves 33 retaining contacts 38, 40 and half 34 has plural bosses 35 holding the contacts in the grooves, (Fig. 6). Recess 36 receives an edge of a ceramic card supporting an integrated circuit device 10 (Fig. 4), and the contacts 38, 40 of Be-Cu or phosphor bronze have extensile spring leaves in the recess which detachably engage the ends of respective circuit paths 16. Terminal post extensions 38.2, 40.2 at the opposite ends of the contacts are spacedly staggered in parallel relationship at a spacing a of approximately 0À1 inch, and in the mounting plural integrated circuit cards 10 are detachably retained in connectors 30 on a panel board 42 of epoxy GRP so that the contact extensions pass through the plural correspondingly spaced and staggered apertures 44 of the latter (Fig. 7), having row spacing b=0À1 inch and adjacent spacing c=0À05 inch. Connecting wires wrapped around the protrusions of the contact extensions provide inter-circuit links as required.