摘要:
According to the present invention a technique for providing a planarized substrate with dendritic connections of solder balls, especially a multi-layer ceramic substrate is provided. In the case where the substrate has a raised central portion on the top surface on which are disposed top surface metallurgy pads, a layer of conformable photoimagable material is placed over the top surface.The photoimagable material is exposed and developed in a pattern corresponding to the pattern of the top surface metallurgy pads to form vias in the photoimagable material. Copper is plated in the vias in contact with the top surface metallurgy pads. The exposed surface of the photoimagable surface is then planarized, preferably by mechanical polishing to form a flat planar surface, with the ends of the vias exposed. Dendritic connector pads are then grown on the exposed ends of the vias to which solder ball connections of an I/C chip are releasably connected.
摘要:
According to the present invention a technique for providing a planarized substrate with dendritic connections of solder balls, especially a multi-layer ceramic substrate is provided. In the case where the substrate has a raised central portion on the top surface on which are disposed top surface metallurgy pads, a layer of conformable photoimagable material is placed over the top surface.The photoimagable material is exposed and developed in a pattern corresponding to the pattern of the top surface metallurgy pads to form vias in the photoimagable material. Copper is plated in the vias in contact with the top surface metallurgy pads. The exposed surface of the photoimagable surface is then planarized, preferably by mechanical polishing to form a flat planar surface, with the ends of the vias exposed. Dendritic connector pads are then grown on the exposed ends of the vias to which solder ball connections of an I/C chip are releasably connected.
摘要:
Disclosed is an admixture which is curable to form a crack resistant, photosensitive polycyanurate resist. Also disclosed is a structure for its use and process of making. The resist can be tailored to be either positively or negatively sensitive to actinic radiation. Because of its improved thermal and mechanical properties, the cured resist is suitable for use at high temperature, such as in electronic packaging applications.
摘要:
A method for filling a hole in a printed wiring board (PWB) and the resultant PWB. During an intermediate stage in fabrication, a PWB comprises a lamination of dielectric sheets with metalizations on various layers and a plated through hole (PTH). A photoimageable material is formed on a surface of the laminate and covers the PTH. The photoimageable material in a region covering the PTH is partially cured by exposure to light. The remainder of the photoimageable material is developed away. Then, the partially cured photoimageable material in the region of the PTH is pressed into the PTH to form a plug. By application of heat during or after the forcing step, the plug is further cured to a hard condition. For some applications, the plug is mechanically abraded to be flush with one or both surfaces of the laminate. The plug can serve as a solder mask or permit another layer of low viscosity photoimageable material to be formed over the laminate such that the hole, now plugged, will not interfere with the formation of such additional layer.
摘要:
An electronic package assembly where a low profile integrated circuit chip package is soldered to an organic (e.g., epoxy resin) substrate, e.g., a printed circuit board or card, the projecting conductive leads of the integrated circuit chip package and the solder which substantially covers these leads (and respective conductors on the substrate) having been substantially covered with ultraviolet photocured encapsulant material (e.g., an epoxy resin or a cyanate with a photoinitiator and silica) to provide reinforcement for the solder-lead connections. The encapsulant material is dispensed about the solder and lead joints following solder reflow and solidification so as to substantially surround the solder and any portions of the leads not covered with solder.
摘要:
Chip carrier packages, integrated circuits, wiring boards, and assemblies in computer systems are made having conductive adhesive interconnections. Electrically conductive polymer paste with metal particles and powders are used with photoimagable polymer films to form the interconnection structure. These articles are produced with screening and printing processes using a screening head and printing machine.
摘要:
A structure comprising a metallic surface, a layer of a polymeric material and a water soluble polymeric material located between the metallic surface and the layer of polymeric material, and process of fabricating such are provided. The structure exhibits enhanced adhesion between the metallic surface and the polymeric material.
摘要:
Disclosed is a sculpted probe pad and a gray scale etching process for making arrays of such probe pads on a thin flexible interposer for testing the electrical integrity of microelectronic devices at terminal metallurgy. Also used in the etching process is a novel fixture for holding the substrate and a novel mask for 1-step photolithographic exposure. The result of the invention is an array of test probes of preselected uniform topography, which make ohmic contact at all points to be tested simultaneously and nondestructively.
摘要:
Chip carrier packages, integrated circuits, wiring boards, and assemblies in computer systems are made having conductive adhesive interconnections. Electrically conductive polymer paste with metal particles and powders are used with photoimagable polymer films to form the interconnection structure. These articles are produced with screening and printing processes using a screening head and printing machine.
摘要:
Reinforcement members are disposed along only the transverse edge regions of selected flexible cables of an integral chip carrier and cable assembly, and along only the respectively aligned end areas of the chip carrier portion of the assembly. The reinforcement members may be disposed along all of the flexible cables and end areas of the assembly, or on only selected cable and end area portions of the assembly. The reinforcement members are formed of a tough tear resistant polymer material, such as a hot melt adhesive or polymer tape or film.