Electronic device enclosure method

Abstract

Abstract 1,101,029. Semi-conductor devices. CORNING GLASS WORKS. 12 Oct., 1965 [12 Oct., 1964], No. 43264/65. Heading H1K. A package for an electronic device comprises a substrate, having adherent contact pads to which outwardly-extending leads are attached and a glass ring fused to the edge of the substrate over the leads so that they are hermetically sealed. A glazed alumina substrate (10) is cleaned and has a layer (12) of nickel applied to one face by electroless deposition, Fig. 1 (not shown). The nickel layer is machined to form contact pads 16, Fig. 6, using an ultrasonic impact grinder (14, Fig. 1). The ends of leads 18, which may be in the form of a comb 30, are joined to contact pads 16 by ultrasonic vibration bonding, and a glass ring 22 is placed over the leads and heated to fuse it to substrate 10 forming hermetic seals with the leads, Figs. 3, 4 and 5 (not shown). A semi-conductor device (34) is placed in the cavity and connected to the various contact pads by direct bonding (37) or by wires (38) as appropriate, and a glazed alumina cover 40 is bonded to ring 22 to form the completed package, Fig. 7 (not shown). The portion 32 connecting the leads 18 together may be removed either before mounting the semi-conductor device or after sealing the housing. The substrate 10 may be of a ceramic, e.g. alumina or beryllium, a glazed ceramic, a glass ceramic, a glass, or a glazed metal. The conductive coating (12) may be a metal or metal alloy applied by electroless deposition or vapour deposition and very thin electroless coatings may be thickened by electrolytic deposition. The conductive layer (12) may also be etched, or sand blasted or applied in the required pattern to form contact pads 16. The leads may be of nickel, "Kovar" (Registered Trade Mark), copper clad iron-nickel (Dumet), Niron (nickel-iron) or Sylavania 4 (iron-nickel-chromium), and may also be joined to the contact pads by resistance welding, brazing or soldering. The semi-conductor device may be a transistor, a diode, or an integrated circuit. The compositions of suitable glasses for ring 22 which will seal to "Kovar" (Registered Trade Mark) and Dumet leads are also described.

Inventors

• 👤 John Spiegler

Bibliographic Details