Abstract:
A heated and pressed printed wiring board is made by filling via holes formed in layers of insulating film of the wiring board with an interlayer conducting material. The insulating film is stacked with conductor patterns, and each conductor pattern closes a via hole. The interlayer conducting material forms a solid conducting material in the via holes after a heating a pressing procedure. The solid conducting material includes two types of conducting materials. The first type of conducting material includes a metal, and the second type of conductive material includes an alloy formed by the metal and conductor metal of the conductor patterns. The conductor patterns are electrically connected reliably without relying on mere mechanical contact.
Abstract:
A BGA test socket for use in standard testing and burn-in testing of BGA dies and method for testing such dies is disclosed wherein a die contact insert made of silicon or ceramic using standard IC fabrication technology is used. Through using such an insert, even small scale (pitch) BGA dies can be reliably tested including chip scale packaged (“CSP”) BGA dies. Furthermore, using such an insert allows a conventional socket to be adapted for use with a wide variety of both BGA dies and other varieties. A method for using the device is disclosed which overcomes current static electricity problems experienced in testing CSP BGA dies through closing the test socket before removing the die deposit probe.
Abstract:
A method for making a fine electrically conductive grid embedded in a polymer substrate. The method includes the steps of providing a polymer substrate, forming a pattern of grooves in the substrate, filling the grooves with electrically conductive powder, and then applying heat and/or pressure to the substrate. The application of heat and/or pressure to the substrate causes the grooves to collapse inward against the conductive powder. Collapsing the grooves compacts the conductive powder within the groove, thereby establishing a continuously conductive grid line or circuit. The narrow grid lines that result allow more light to transmit through the substrate. The method allows grid lines to be made with higher aspect ratios (ratio of line depth to line width) than is possible by previous methods.
Abstract:
According to the invention, a microperforation (PMP) process step is combined with the lamination process. To this end, a dielectric layer are and a prefabricated product are placed between a support and a perforation die. The prefabricated product is partially covered by a conducting layer forming structures to be contacted by microvias. Pressure is applied on the perforation die, perforation tips of the perforation die forming microvias for contacting the structures. A surface of the dielectric layer or the prefabricated product is configured or coated to in a manner that the prefabricated product and the dielectric layer stick to each other after the pressure has been applied.
Abstract:
A blind via structure, and associated laser ablation methods of formation, that includes a blind via within a photoimageable dielectric (PID) layer on a substrate, such that the sidewall of the blind via makes an obtuse angle with the blind end of the blind via. The obtuse-angled sidewall may be formed by executing two processes in sequence. In the first process, photoimaging of the PID layer, with selective exposure to ultraviolet light, results in one or more blind vias having acute-angled sidewalls. The photoimaging cross links the PID material that had been selectively exposed to ultraviolet light such that a subsequent developing step removes PID material not cross linked, or weakly cross linked, to simultaneously form multiple blind vias having different sized openings. In the second process, laser ablation is selectively employed to remove the acute-angled sidewalls from particular blind vias in a way that forms replacement obtuse-angled sidewalls in the laser-ablated blind vias. Alternatively, the first process involving photoimaging may be omitted such that the second step involving laser ablation forms the entire obtuse-angled blind via. The resultant blind via structure includes at least one blind via having an obtuse-angled sidewall, and optionally, at least one blind via having an acute-angled sidewall.
Abstract:
A method of manufacturing a PCB comprising the steps of: forming through-holes in a substrate having releasing layers on front and back faces; filling conductive paste in the through-holes; removing the releasing layers and disposing metal foil on both faces of the substrate; and heat pressing them. A diameter of the through-holes is larger than that of corresponding holes formed on the releasing layers. According to the present invention, when the conductive paste is compressed, conductive paste protruding from the surface of the substrate is trapped at the edges of the through-holes. This configuration prevents short circuits with undesirable wiring patterns. So, an enough amount of the conductive paste can protrude from the surface of the substrate. Therefore, after the compression, stable electric connections inside the conductive paste and between the conductive paste and the metal foils are ensured, thus PCBs with superior reliability can be produced.
Abstract:
A substrate for electronic packaging, the substrate having a discrete, generally prismatoid, initially electrically conductive valve metal solid body with one or more spaced apart, original valve metal vias each individually electrically islolated by a porous oxidized body portion therearound. A pin jig fixture for mechanically masking a metal surface, the pin jig fixture having an anodization resistant bed of pins each pin having a leading end surface for intimate juxtaposition against a metal surface to mask portions thereof.
Abstract:
A circuit includes a substrate having a dielectric layer with a first surface and a second surface. A conductive layer is formed on the first surface. A beveled via is formed in a dielectric layer of the substrate. The via has a first opening of a first width in the first surface, and a second opening of a second width in the second surface, the second width being greater than the first width. A conductive plug is connected to the conductive layer. The plug is formed in the via and extends from adjacent the first opening toward the second opening, and terminates adjacent the second opening at a plug interface surface. A conductive solder ball is connected to the plug interface surface and extends to protrude from the second surface.
Abstract:
Conductive paste containing tin particles and silver particles is packed in a substantially cylindrical via hole formed in a thermoplastic resin film that interposes between conductor patterns and is hot-pressed from both sides. When the metal particles contained in the conductive paste are sintered to form a unified conductive compound, the volume of the conductive paste shrinks. Synchronously, the resin film around the via-hole protrudes into the via-hole. Therefore, the shape of the side wall on the cross-section of the conductive compound provides an arch shape, and a side wall adjacent to a junction part of the conductive compound, which contacts the conductor pattern, is formed with an inclination. Therefore, it is possible to prevent the stress concentration due to deformation of the board.
Abstract:
A measuring mechanism for a BGA-IC capable of facilitating and assuring the contact between a soldering ball of a BGA-IC and a BGA contact seat even if a foreign matter is sandwiched therebetween, and also capable of saving time involved in recontact therebetween, and of shortening measuring time. The measuring mechanism for a BGA-IC comprising a substrate including a BGA contact seat which is embedded therein and has a conical contact surface, wherein the BGA contact seat is connected to a tester, and the BGA-IC has the soldering ball and wherein the soldering ball contacts the conical contact surface of the BGA contact seat when the BGA-IC is tested.