Abstract:
A ball grid array package utilizes solder balls (14) having central cores of a material with a higher melting point than solder material surrounding the core. When the ball grid package (12) and motherboard assembly (10) are heated to the melting point of the solder material, the cores remain solid and function as spacers in preventing direct contact of the package surface and the motherboard surface, thus preventing molten solder from being squashed and flowing to adjacent ball contacts.
Abstract:
An interconnector (10) is provided that improves the reliability of an electrical and mechanical connection between two substrates (16, 18). An interconnector (10) according to the invention includes a compliant core (12) surrounded by an electrically conductive layer (14).
Abstract:
A ball grid array device (10) utilizes solder balls (24) comprised of a core (34) having a relatively high melting temperature and a solder coating (30) having a lower melting temperature. The core (34) may be metal, a polymer or a metal-coated polymer.
Abstract:
Disclosed is a connector structure on a substrate (10) which includes at least one first solder portion (16) on the surface of the substrate; at least one second solder portion (18) connected to each of the at least one first solder portions; and an epoxy layer (20) disposed about the at least one first and second solder portions in such a manner as to cover the first solder portion and contact, but not cover, the second solder portion. Also disclosed is a connector structure on a substrate which includes at least one first solder portion on the surface of said substrate; at least one second solder ball portion connected to the at least one first solder portions; wherein the melting point of the second solder ball portion is relatively higher than that of the first solder portion. Finally, disclosed is a method of testing the solderability of the above structures.
Abstract:
A foamed bulk metallic glass electrical connection is formed on a substrate of an integrated circuit package. The foamed bulk metallic glass electrical connection exhibits a low modulus that resists cracking during shock and dynamic loading. The foamed bulk metallic glass electrical connection is used as a solder bump for communication between an integrated circuit device and external structures. A process of forming the foamed bulk metallic glass electrical connection includes mixing bulk metallic glass with a blowing agent.
Abstract:
This invention provides an electroconductive particle placement sheet comprising electroconductive particles and an insulating resin sheet. The thickness of the insulating resin sheet is smaller than the average particle diameter of the electroconductive particles. Electroconductive particles are protruded from the reference plane (P1) on at least one side of the insulating resin sheet. The electroconductive particle in is part protruded from the reference plane (P1) is covered with a layer formed of the same resin as in the insulating resin sheet. The electroconductive particle placement sheet is characterized by satisfying a relationship of h1 > h2 wherein h1 represents an average protrusion height, which is the average of distance between the reference plane (P1) and a tangential line (L1), which is a tangential line parallel to the reference plane (P1) of the electroconductive particle and is in contact with the part protruded from the reference plane (P1), and h2 represents an average protrusion height which is the average of distance between the reference plane (P2) and a tangential line (L2), which is a tangential line parallel to the reference plane (P2) of the electroconductive particle and is on the side opposite to the tangential line (L1), provided that, when the tangential line (L2) is within the insulating resin sheet, h2 0.