摘要:
Methods for forming pastes of powder particles coated with an electrically conductive coating are described. The powder particles, with or without an optional first conductive coating layer applied to their surface, are placed in contact with a cathode surface and immersed in an electroplating solution. An anode covered with a nonconducting but ion-permeable membrane is immersed in the solution in close proximity to the cathode. Agitation to move and gently tumble the powder over the cathode surface is provided. The powder particles are plated with a metal or metal alloy coating by biasing the anode with a positive voltage relative to the cathode. The coated powder is removed, rinsed and dried. The powder is added to a polymer material to form a paste which is heated to fuse the powder coating surfaces to form a network of interconnected particles and is further heated to cure the polymer. When the paste is disposed between adjacent electrically conductive surfaces, the coated particles fuse to the electrically conductive surfaces to form electrical interconnections.
摘要:
The present invention provides a unique, high density, electronic package having a conductive composition for filling vias or through holes to make reliable vertical or Z-connects from a dielectric layer to adjacent electrical circuits. The through holes may be plated or non-plated prior to filling. A description for making high density electronic packaging using this feature is also disclosed.
摘要:
A socketable ball grid array structure is disclosed which comprises mechanically rigid (compared to solder alloys) balls coated with noble contact metals joined to the chip carrier terminals by means of a novel electrically conducting adhesive. Because of the nature of the filler that includes conducting particles with a fusible coating and the appropriate selection of the polymer resin used in the adhesive, the balls are attached to the module in a compliant and resilient manner while leaving the majority of the bottom surface of the balls pristine. The array of balls can therefore be plugged into mating sockets in a printed circuit board forming a demountable contact. This facilitates easy removal of the socketable BGA from a board for repair or upgrade purposes as well as allows ease of plugging and unplugging of these BGA's into test and burn-in boards.
摘要:
A socketable ball grid array structure is disclosed which comprises mechanically rigid (compared to solder alloys) balls coated with noble contact metals joined to the chip carrier terminals by means of a novel electrically conducting adhesive. Because of the nature of the filler that includes conducting particles with a fusible coating and the appropriate selection of the polymer resin used in the adhesive, the balls are attached to the module in a compliant and resilient manner while leaving the majority of the bottom surface of the balls pristine. The array of balls can therefore be plugged into mating sockets in a printed circuit board forming a demountable contact. This facilitates easy removal of the socketable BGA from a board for repair or upgrade purposes as well as allows ease of plugging and unplugging of these BGA's into test and burn-in boards.
摘要:
A new interconnection scheme is disclosed for a tape automated bonding (TAB) package, a flip chip package and an active matrix liquid crystal display (AMLCD) panel, where an electrically conducting adhesive is used to form an electrical interconnection between an active electronic device and its components. The electrically conducting adhesive can be a mixture comprising a polymer resin, a no-clean solder flux, a plurality of electrically conducting particles with an electrically conducting fusible coating which provides a metallurgical bond between the conducting particles as well as to the substrates. The advantages of using the electrically conducting adhesives include reduction in bonding pressure and/or bonding temperature, control of interfacial reactions, promotion of stable metallurgical bonds, enhanced reliability of the joints, and others.
摘要:
Pastes of dendrite particles coated with an electrically conductive coating are described. A surface is placed in contact with an electrolytic or electroless plating solution. Dendrites are formed on the surface. The dendrites are exposed to another plating solution to plate a coating on the surface of the dendrites. The coated dendrites are removed from the surface to form a powder of coated dendrites. The powder is added to a polymer material to form a paste. The paste is disposed between electrical contacts on adjacent surfaces. The paste is heated to fuse the dendrite surfaces to form a network of fused dendrites which are also fused to the electrical contacts. The paste is further heated to cure the polymer to form electrical interconnections between the electrical contacts on the adjacent surfaces.
摘要:
A new interconnection scheme is disclosed for a tape automated bonding (TAB) package, a flip chip package and an active matrix liquid crystal display (AMLCD) panel, where an electrically conducting adhesive is used to form an electrical interconnection between an active electronic device and its components. The electrically conducting adhesive can be a mixture comprising a polymer resin, a no-clean solder flux, a plurality of electrically conducting particles with an electrically conducting fusible coating which provides a metallurgical bond between the conducting particles as well as to the substrates. The advantages of using the electrically conducting adhesives include reduction in bonding pressure and/or bonding temperature, control of interfacial reactions, promotion of stable metallurgical bonds, enhanced reliability of the joints, and others.
摘要:
A method using an electrically nonconductive cathode chamber with at least part of its wall area rendered permeable to ions and electrolytic solutions; premixing a predetermined quantity of an electroconductive powder and a first electroplating solution; filling the cathode chamber with the solution/powder mixture and a plurality of electroconductive spheres; disposing an electroconductive cathode ball connection in contact with the spheres and powder particles; securing the cathode chamber to a cap which is part of a rotary assembly that allows the rotation of the cathode chamber about its axis without twisting the aforementioned cathode ball connection positioned within said chamber; placing the cathode chamber within an anode chamber containing a second electroplating solution and an anode; rotating the cathode chamber on its axis using the rotary assembly; biasing the anode with a positive voltage in reference to the cathode ball connection causing the electroplating of a metallic coating on the surface of the said powder while it is tumbled within the rotating cathode chamber; and rinsing, cleaning, and optionally ball milling the mixture of plated powder particles and the spheres to enable easy recovery of the plated powder.
摘要:
A new interconnection scheme of a ball grid array (BGA) module is disclosed where a solder ball is connected to the BGA module by use of an electrically conducting adhesive The electrically conducting adhesive can be a mixture comprising a polymer resin, no-clean solder flux, a plurality of electrically conducting particles with an electrically conducting fusible coating and others. The solder balls in a BGA module can also be connected to a printed circuit board by use of another electrically conductive adhesive which can be joined at a lower temperature than the first joining to the BGA module. Additionally, an electrically conducting adhesive can be formed into electrically conducting adhesive bumps which interconnect an integrated circuit device to the BGA module.
摘要:
A structure and method of fabrication are described. The structure is a combination of a polymeric material and particles, e.g. Cu, having an electrically conductive coating, e.g. Sn. Heat is applied to fuse the coating of adjacent particles. The polymeric material is a thermoplastic phenoxy polymer or a styrene allyl alcohol resin. The structure is disposed between two electrically conductive surfaces, e.g. chip and substrate pads, to provide electrical interconnection and adhesion between their pads.