公开(公告)号：SE345343B

公开(公告)日：1972-05-23

申请号：SE312367

申请日：1967-03-07

Applicant: IBM

Inventor： CHANCE D ,  IM S ,  PERRI J ,  RISEMAN J

IPC: B23K1/005 ,  H01L29/12 ,  H01R12/71 ,  H01L1/14

Abstract: 1,162,184. Semi-conductor devices; printed circuit assemblies. INTERNATIONAL BUSINESS MACHINES CORP. 9 March, 1967, No. 11043/67. Headings H1K and H1R. Monolithic or integrated semi-conductor devices are gold-coated on their lower surfaces and hot pressure bonded to superposed gold and chromium layers at the bottom of cavities in a substrate of glass or ceramic (e.g. 96% alumina). The cavities are formed by pressing the green ceramic or by bonding an apertured alumina sheet to an alumina blank. Each device has a plurality of built-up contacts extending through a protective glass coating on its upper surface and these lie in substantially the same plane as lands on the top surface of the substrate and which consist of aluminium, copper, or one or more noble metals. (For example the lands may have superposed gold, copper, and chromium layers). A plate is provided with conductive tracks suitably placed to interconnect adjacent contacts and lands. Suitable plates are aluminium or copper foils, paper, resin-reinforced fibrous materials, tetrafluoroethylene resins, polyethylene-terephthalate resins, and polyimide resins. The conductive tracks are formed on these, preferably on an intermediate acrylate resin parting layer, by laminating and etching, or by masked evaporation and may consist of aluminium, copper, or one or more noble metals. (A track may have superposed gold, lead, tin and copper layers). Preferably the plate is transparent so that visual alignment may be used in the bonding process, and is preferably insulating so that interconnection tests may be made before bonding. The backing may be clamped to the devices and substrate on a hot stage (which may have orienting pegs engaging the backing) and the assembly bonded by a solder reflow technique using lead-tin solder. Instead, single or multi-tipped thermocompression bonding machines may be used, the tips penetrating the backing during bonding. If ultrasonic bonding heads are used these are first heated to penetrate the backing and ultrasonic energy then supplied to affect the bonding. Laser or electron beam bonding may be used instead. The bonding layer is pulled away from the bonded contact tracks and lands, any parting layer being dissolved away. Alternatively the backing plate may be multilayered and consist of polyimide sheets bearing conductive tracks formed by masked evaporation or electrochemical deposition. Through-holes in the backing are metallized to provide interconnection between tracks in the various planes. Such a backing plate remains in place after bonding to interconnect the devices on the substrate.