With Disassembling Of Bonded Joint (e.g., Desoldering) Patents (Class 228/191)
  • Patent number: 6225206
    Abstract: An electrical structure, and associated method of fabrication, for reducing thermally induced strain in a conductive structure that couples a first substrate to a second substrate. The first substrate may include a chip or a module. The second substrate may include a chip carrier or a circuit card. Thus, the present invention encompasses such coupling as chip to chip carrier, chip to circuit card, and module to circuit card. The conductive structure includes a first conductive body and a second conductive body. The first conductive body is attached to the first substrate and the second conductive body is attached to the second substrate. The first conductive body may include a solder bump, while the second conductive body may include a eutectic alloy, such as a eutectic alloy lead and tin. Alternatively, the second conductive body may include a non-eutectic alloy whose melting point is below the melting point of the first conductive body.
    Type: Grant
    Filed: May 10, 1999
    Date of Patent: May 1, 2001
    Assignee: International Business Machines Corporation
    Inventors: Miguel Angel Jimarez, Cynthia Susan Milkovich, Mark Vincent Pierson
  • Patent number: 6201930
    Abstract: A chip removal and replacement system is designed for safely and easily removing or reattaching components from a printed circuit board. The system includes an automatic suction system for lifting a component which has been removed. A nozzle connection and replacement mechanism is provided for interchanging nozzles. The system is also provided with an improved circuit board holder, a circuit board auxiliary preheater, and a simplified control system with one touch removal and replacement.
    Type: Grant
    Filed: February 22, 1999
    Date of Patent: March 13, 2001
    Assignee: Metcal, Inc.
    Inventors: Seth Close, Mike Carlomagno, Raymond Lui, Jeff Wallingford
  • Patent number: 6142358
    Abstract: Break-away tethers to secure electronic, mechanical, optical, or other microstructures, during release from one substrate and transfer to another. Microstructures are fabricated with integrated tethers attaching them to a first substrate. The structures are undercut by etching and contacted and bonded to a second substrate. First and second substrates are separated, breaking the tethers.
    Type: Grant
    Filed: May 31, 1997
    Date of Patent: November 7, 2000
    Assignee: The Regents of the University of California
    Inventors: Michael B. Cohn, Roger T. Howe
  • Patent number: 6131794
    Abstract: A shaving or shearing blade utilized in dressing solder joint chip technologies without the use of heat or a copper block wicking process. In essence, any solder debris resulting from the solder shaving process as implemented by the shaving blade is removed through the intermediary of a vacuum arrangement located as an integral structure in the shaving blade so as to inhibit the potential formation of electrical shorts or causing solder damage in subsequent replacement chip joins or other assembly operations.
    Type: Grant
    Filed: June 11, 1997
    Date of Patent: October 17, 2000
    Assignee: International Business Machines, Corp.
    Inventors: Jac Anders Burke, David Charles Olson, James Edward Tersigni, Jeffrey Scott Wolfe
  • Patent number: 6053393
    Abstract: A shaving or shearing blade utilized in dressing solder joint chip technologies without the use of heat or a copper block wicking process. In essence, any solder debris resulting from the solder shaving process as implemented by the shaving blade is removed through the intermediary of a vacuum arrangement located as an integral structure in the shaving blade so as to inhibit the potential formation of electrical shorts or causing solder damage in subsequent replacement chip joins or other assembly operations.
    Type: Grant
    Filed: March 11, 1999
    Date of Patent: April 25, 2000
    Assignee: International Business Machines Corp.
    Inventors: Jac Anders Burke, David Charles Olson, James Edward Tersigni, Jeffrey Scott Wolfe
  • Patent number: 6050476
    Abstract: A reworkable cold welded microelectronic multi-chip module contains cold welded microelectronic chips in which the chip's cold weld metal bonding pads (3) are constructed of a metal having one hardness and the corresponding cold weld metal bonding pads of the multi-chip module's substrate (5) are of a different greater hardness, which, despite the difference in hardness, cold weld to one another. Two forms of Indium preferably serve as the metals. If for any reason the chip must be removed from the module, it is found that the cold weld breaks at a predictable location. A new microelectronic chip may thereby be cold welded to the module substrate as a replacement. New rework and testing procedures are thereby made possible.
    Type: Grant
    Filed: September 19, 1998
    Date of Patent: April 18, 2000
    Assignee: TRW Inc.
    Inventors: Karen E. Yokoyama, Gershon Akerling
  • Patent number: 5950906
    Abstract: A method of reversibly brazing surfaces together. An interface is affixed to each surface. The interfaces can be affixed by processes such as mechanical joining, welding, or brazing. The two interfaces are then brazed together using a brazing process that does not defeat the surface to interface joint. Interfaces of materials such as Ni-200 can be affixed to metallic surfaces by welding or by brazing with a first braze alloy. The Ni-200 interfaces can then be brazed together using a second braze alloy. The second braze alloy can be chosen so that it minimally alters the properties of the interfaces to allow multiple braze, heat and disassemble, rebraze cycles.
    Type: Grant
    Filed: May 20, 1997
    Date of Patent: September 14, 1999
    Assignee: Sandia Corporation
    Inventors: Jim D. Pierce, John J. Stephens, Charles A. Walker
  • Patent number: 5934545
    Abstract: A method and apparatus allow securing of balls to ball grid array electronic components. A component having a surface with rows and columns of electrical contact solder pads is removed from a printed circuit board for rework. Excess solder is removed from the solder pads and the surface is pressed against a stencil having a pattern of holes corresponding to the component contact pad pattern. Each of the holes is filled with a solder ball. The assembly is heated to melt the at least the solder pads. Where lower melting solder balls are used, the pads and balls both melt. Where high melting temperature solder balls are used, only the solder pads melt. The assembly is cooled to solidify melted solder, the stencil is removed, the component is cleaned and is ready for reuse.
    Type: Grant
    Filed: February 21, 1997
    Date of Patent: August 10, 1999
    Inventor: Thomas A. Gordon
  • Patent number: 5921462
    Abstract: A method and apparatus enables the securing of balls to ball grid array electronic components. A component having a surface with rows and columns of electrical contact pads is removed from a printed circuit board for rework. Excess solder is removed from the pads and the surface is pressed against a stencil having a pattern of holes corresponding to the component contact pad pattern. The holes are filled with a paste continuing flux and solder particles. The assembly is heated to melt the solder particles, which agglomerate into generally spherical balls bonded to the contact pads. The assembly is cooled, the stencil is removed, the component is cleaned and is ready for reuse. Preferably, the stencil is formed from a material that bows in one direction when heated, so that when the stencil is held against the pad array surface and heated, bowing forces will very tightly press the stencil against the surface, preventing molten solder from migrating between surface and stencil.
    Type: Grant
    Filed: February 21, 1997
    Date of Patent: July 13, 1999
    Inventor: Thomas A. Gordon
  • Patent number: 5816479
    Abstract: Improved welding method and padeye processing speeds up the connection of individual joints by peripheral fusion welding while the joint to be added stands vertically atop an existing pipe string also standing vertical in the rig floor. A plurality of welders can operate to speed up completion of the weld by removing heat from the pipe during the welding process. Heat is removed by the use of fluid cuffs near the weld area and, optionally, by using a spool within the pipe string to dispense expansion cooled air against the inner pipe wall in the vicinity of the weld. A special improved padeye is provided for welding near the pipe ends for handling. The padeye has a divided profile, a hole for a lifting shackle, and it will be accepted within the skirt of the lead system of the driving hammer. The upper end of the padeye can be cut from the pipe while the pipe is resting, on rig related structure, on the lower surface of the padeye.
    Type: Grant
    Filed: June 9, 1997
    Date of Patent: October 6, 1998
    Assignee: Premiere, Inc.
    Inventors: Lee Matherne, Tommy A. Hebert, John D. Jeter
  • Patent number: 5806753
    Abstract: A method of forming a bond structure for use with integrated circuits and semiconductor electronics and carrier assemblies is disclosed. Metallurgical paste is screen printed through a stencil and the stencil is left in place during the reflow process. The melting point of the bond structure and the metallurgical paste is lower than the melting point of interconnects on the electronic components and less than the decomposition temperature of the carrier assemblies to which the electronic components are bonded.
    Type: Grant
    Filed: December 22, 1995
    Date of Patent: September 15, 1998
    Assignee: International Business Machines Corporation
    Inventors: James Daniel Bielick, Mark Kenneth Hoffmeyer, Phillip Duane Isaacs, Thomas Donald Kidd, David Allen Sluzewski
  • Patent number: 5794331
    Abstract: A process for exchanging a detection module hybridized by welding beads, balls or bumps, employs an interconnection support having first and second groups of welding elements. The module to be hybridized is provided with blocks wettable by the weld, and positioned facing elements of the first group during hybridization. A replacement module is provided with blocks wettable by the weld and positioned facing elements of the second group during hybridization. The module which has been hybridized is dehybridized, and the replacement module is hybridized by means of the second group of elements.
    Type: Grant
    Filed: May 31, 1996
    Date of Patent: August 18, 1998
    Assignee: Commissariat a l'Energie Atomique
    Inventors: Michel Ravetto, Jean-Paul Chamonal, Fran.cedilla.ois Marion, Jean-Louis Pornin
  • Patent number: 5769989
    Abstract: A configuration of surface-mounted circuit assembly has four layers, namely, an integrated circuit device, an adhesive layer, a solder layer and the carrier board. The integrated circuit device is attached to the solder layer which sets on top of the carrier board, with the adhesive layer between the integrated circuit device and the solder layer. The carrier board has at least one via located beneath where the integrated circuit is located. The via is filled with solder such that the solder layer at which the integrated circuit device is situated is thermo-conductively connected to the back side of the carrier board. This configuration allows the integrated circuit device to be easily removed from the carrier board by the application of heat to the back side of the carrier board.
    Type: Grant
    Filed: September 19, 1995
    Date of Patent: June 23, 1998
    Assignee: International Business Machines Corporation
    Inventors: Mark Kenneth Hoffmeyer, David A. Sluzewski
  • Patent number: 5735450
    Abstract: An apparatus for heating a module mounted on a card includes a heating chamber adapted to receive the card and module, a nozzle adapted to surround the module and provide a flow of heated gas thereover, and a heated support surface for heating a bottom surface of a card immediately underlying the module. The method of removing and replacing a module on a card includes preheating the card and module prior to heating the contact sites to a solder reflow temperature and also preheating a card and a replacement module to an equilibrium temperature prior to increasing the temperature of the contact sites to the reflow temperature. The apparatus and method embodying the present invention effectively addresses the problem of providing a faster heating cycle, and a more even temperature distribution across the contact sites of the module and card.
    Type: Grant
    Filed: June 21, 1996
    Date of Patent: April 7, 1998
    Assignee: International Business Machines Corporation
    Inventors: Craig Grant Heim, Christian Robert Le Coz, Russell H. Lewis
  • Patent number: 5715592
    Abstract: A printed wiring board, on which an electronic parts are mounted and fixed by way soldering, is introduced into a heating furnace for heating at a temperature higher than or equal to a melting temperature of a solder. After sufficiently melting of solder, an impact force and/or a shearing force are applied. By this under a reduced connecting force, the electronic parts are removed from a printed wiring board. On the other hand, since the parts can be easily removed from the printed wiring board. Also, the parts and the printed circuit are separated for collecting useful substance and can improve resistance to enhance recycling efficiency.
    Type: Grant
    Filed: November 6, 1995
    Date of Patent: February 10, 1998
    Assignee: NEC Corporation
    Inventors: Eiichi Mori, Sadahiko Yokoyama, Masatoshi Iji, Yuji Ikuta
  • Patent number: 5709336
    Abstract: A dendrite surface is provided on each of the electrical contacts of a substrate, such as a test board, chip carrier, or printed wiring board. The electrical contacts on the substrate are arranged in a mirror image of the input/output pads on a wirebond chip from which the wire leads have been removed from, or not initially provided on, each of the input/output pads. The wirebond chip is aligned with the substrate, and the respective contact brought into electrical communication with each other. The wirebond chip may be removed after testing or other temporary attachment purpose, or permanently encapsulated with at least a portion of the substrate in a permanent assembly. The present invention permits wirebond chips to be selectively attached temporarily or permanently, i.e., have a pluggable capability, as well as the ability to allow a full array of I/O pad design.
    Type: Grant
    Filed: May 31, 1996
    Date of Patent: January 20, 1998
    Assignee: International Business Machines Corporation
    Inventors: Anthony Paul Ingraham, William Tze-You Chen
  • Patent number: 5655703
    Abstract: The method for soldering a chip to a substrate to form a module and then soldering the module to a circuit board includes selecting a three level hierarchy of solders by the temperature required to melt. By this method, a module can be soldered to and de-soldered from a circuit board without affecting adversely the solder between the chip and the substrate. The package formed by this method is free of faults that are caused frequently during both manufacture and service.
    Type: Grant
    Filed: May 25, 1995
    Date of Patent: August 12, 1997
    Assignee: International Business Machines Corporation
    Inventors: Miguel Angel Jimarez, Amit Kumar Sarkhel, Lawrence Harold White
  • Patent number: 5620208
    Abstract: A boltless, reusable flange system for joining metal piping includes a circular, wedge-shaped tongue on an upper flange for mating with a groove containing a fusible alloy in a lower flange. The lower flange includes a heating element for melting the fusible alloy, and a thermocouple device to sense the alloy temperature. Heat can be controlled and supplied from a remote source and monitored by a remote temperature indicator. The upper flange is positioned above the lower flange, tongue and groove aligned, and the lower flange is heated until the fusible alloy melts to allow the upper tongue to settle down within the lower groove. Upon removal of the heat, the alloy hardens to further bring the two flanges together in a solid and sealed couple, compressing an optional gasket.
    Type: Grant
    Filed: May 19, 1995
    Date of Patent: April 15, 1997
    Assignee: Lockheed Idaho Technologies Company
    Inventor: Robert J. Kirkham
  • Patent number: 5601675
    Abstract: An electronics device has unpackaged chips or other small components mounted on a carrier and wire-bonded to carrier wiring traces. The rear chip faces have a layer of adhesive which overlies a layer of solder or other fusible material, and which adheres to a pad area of the carrier. To replace a chip, its solder layer is melted, and the chip and adhesive are pulled off. Reapplying an adhesive layer allows a new chip to be mounted on the carrier and bonded to the traces.
    Type: Grant
    Filed: December 6, 1994
    Date of Patent: February 11, 1997
    Assignee: International Business Machines Corporation
    Inventors: Mark K. Hoffmeyer, David A. Sluzewski
  • Patent number: 5560841
    Abstract: A method in which the interface at which two components are bonded together, by a bonding material that has a lower melting temperature than the material from which the components are made, is heated to the melting temperature of the bonding material, allowing the components to be separated without cutting any of the interface material.
    Type: Grant
    Filed: October 11, 1994
    Date of Patent: October 1, 1996
    Assignee: United Technologies Corporation
    Inventors: Thomas DeMichael, David N. Cunningham, Philip G. Seeley
  • Patent number: 5560531
    Abstract: A reflow miniovens is available for soldering/desoldering of BGA and SMT individual components on a printed circuit board (PCB). The minioven is comprised of an apparatus whose top and side oven walls are configured as a gas delivery head terminating in a detachable nozzle fitted over the component, which gas delivery head provides gas delivery and vacuum application apparatus, and with the oven bottom being the PCB and the component being soldered/desoldered being positioned directly above a preheater placed in a table on which an open frame construction board holder holding the PCB is supported, allowing placement of any surface on the PCB in direct and unobstructed view of the preheater. The nozzle is configured to direct heated gas to the component and to direct exhaust gas to a level above the PCB to avoid heating neighboring components on the PCB.
    Type: Grant
    Filed: December 14, 1994
    Date of Patent: October 1, 1996
    Assignee: O.K. Industries, Inc.
    Inventor: Czes A. Ruszowski
  • Patent number: 5522535
    Abstract: Methods for facilitating recycling of backing plates in bonded target/backing plate assemblies and structural assemblies for use in these methods are disclosed. The target and backing plate are joined by a solder paste material that may be applied to adjoining surfaces of the target and backing plate at low temperature. The paste solidifies to have a high decomposition temperature on the order of greater than 400.degree. C. Provision of a solder layer having a liquidus temperature of about 100.degree.-250.degree. C. between the backing plate and solder paste allows for easy target and backing plate separation and subsequent backing plate reusage.
    Type: Grant
    Filed: November 15, 1994
    Date of Patent: June 4, 1996
    Assignee: Tosoh SMD, Inc.
    Inventors: Eugene Y. Ivanov, Tatyana F. Grigoriva, Vladimir V. Boldyrev
  • Patent number: 5482200
    Abstract: A method is provided for applying solder to a flip chip pattern on a circuit board. The method involves forming solder bumps on a chip, and then transferring the solder bumps to the flip chip pattern by soldering the chip to the flip chip pattern, and then gradually heating the solder bumps while applying a force to separate the chip from the circuit board, such that the solder bumps substantially remain adhered to the flip chip pattern. The solder is transferred to the flip chip pattern in order to allow a flexible circuit interconnect to be soldered to the flip chip pattern for the purpose of establishing electronic communications between the circuit board's electronic circuit components and a microprocessor emulator. The electronic circuit can then be evaluated and tested without a microprocessor chip being present on the substrate.
    Type: Grant
    Filed: February 22, 1994
    Date of Patent: January 9, 1996
    Assignee: Delco Electronics Corporation
    Inventors: Bruce A. Myers, Ronnie J. Runyon
  • Patent number: 5419481
    Abstract: Process and nozzle device for the soldering and/or desoldering of a land grid array (LGA) component and a corresponding circuit grid present on the surface of a printed circuit board (PCB). The nozzle device comprises a vacuum for supporting the LGA parallel to the PCB, with array contact, a fixed orifice gap for directing hot gas horizontally through the array, and a gas outlet. Uniform circulation of the hot gas is continued to produce uniform, simultaneous melting of the solder array to permit bonding to or desoldering from the circuit array of the PCB while supporting the component parallel to the PCB.
    Type: Grant
    Filed: September 21, 1993
    Date of Patent: May 30, 1995
    Assignee: Air-Vac Engineering Company, Inc.
    Inventors: Clifford S. Lasto, Jeffrey S. Duhaime
  • Patent number: 5346327
    Abstract: A fastener for splicing wires and the like is mace by forming a tubular sleeve of spring material such as phosphor bronze. In its unrestrained shape, the tubular sleeve is too small to receive the wires, but the tubular sleeve is expanded elastically and held expanded by solder, so that the wires can be inserted. Upon the application of heat the solder melts, flowing into the joint and allowing the sleeve to spring back to its original size or at least to the diameter of the wires. The fastener can be mounted on a stud to provide a replacement for the familiar solder cup terminal. An expanded sleeve can be placed around a piece of heat shrinkable tube. When heated, the tube and the sleeve contract, the sleeve reinforcing the tube giving a much greater compressive force during shrinking. The sleeve then becomes a metallic protector for the tube.
    Type: Grant
    Filed: November 10, 1992
    Date of Patent: September 13, 1994
    Inventor: Edward Herbert
  • Patent number: 5344064
    Abstract: A clamp structure is provided for removably rigid attachment to a fluid flow nipple projecting and opening outwardly from a wall portion of an end tank of a heat exchanger and structure is carried by the clamp structure for rigidly attaching a vibratory thereto, whereby the vibrator may be utilized to vibrate the clamp structure and in turn vibrate the fluid flow nipple and the associated end wall tank while heat is applied between the marginal edges of the end wall tank enjoying a solder seam with corresponding marginal edges of a heat exchanger core header plate, the vibration of the header tank during the unsoldering operation preventing a melted solder seam or joint being reformed behind a torch being moved along the solder joint or seam to melt the same.
    Type: Grant
    Filed: August 6, 1993
    Date of Patent: September 6, 1994
    Inventors: Dyrell K. Stokes, Bennie J. Stokes
  • Patent number: 5326016
    Abstract: A method for removing an individual surface mounted electrical component from a printed circuit board retaining a plurality of other components. The individual component has a plurality of leads connected to circuitry on said board by a connection alloy comprising at least two constituent metals and having a given melting point less than that of either of said constituent metals. The method includes the steps of obtaining a removal alloy composed of a plurality of constituent metals and having a particular melting point below the given melting point; heating the removal alloy to a temperature greater than the particular melting point but below the given melting point so as to produce a molten state thereof; contacting the connection alloy on all of the leads with the molten removal alloy and causing thereby a reaction producing a molten state for the connection alloy; and separating the individual component from the printed circuit board while retaining thereon the other components.
    Type: Grant
    Filed: April 15, 1993
    Date of Patent: July 5, 1994
    Inventors: Marvin S. Cohen, Marcio A. Lopes
  • Patent number: 5234149
    Abstract: One or more metallized chip terminals of an electronic device, such as an integrated circuit chip or a laser chip, in one embodiment are temporarily bonded to one or more metallized substrate pads of a wiring substrate, as for the purpose of electrically testing the electronic device. The composition of the metallized chip terminals is suitably different from that of the metallized substrate pads. The pads and terminals are aligned and electrically connected together with a solder located between them under pressure and a temperature above the melting point of the solder. The solder is cooled, and electrical tests of the electronic device are performed by means of electrical access from testing circuitry to the chip terminals through the substrate pads.
    Type: Grant
    Filed: August 28, 1992
    Date of Patent: August 10, 1993
    Assignee: AT&T Bell Laboratories
    Inventors: Avishay Katz, Chien-Hsun Lee, King L. Tai
  • Patent number: 5174016
    Abstract: A chip removal method and apparatus for use with a robotic unit. The chip removal apparatus includes a heated center quill and a soldering unit which cooperate together with a chip removal tool for simultaneously disabling the bonding materials securing a chip to a printed circuit board. The method permits the fine pitch chip device to be removed from the printed circuit board substantially intact for subsequent testing purposes.
    Type: Grant
    Filed: April 25, 1991
    Date of Patent: December 29, 1992
    Assignee: Toddco General, Inc.
    Inventor: Thomas W. Todd
  • Patent number: 5100045
    Abstract: A method for reconditioning diamond abrasive generator wheels having a layer of diamond particles brazed to the grinding surface involves heating the braze, binding the diamond particles above the liquid melting point, reorienting the diamond particles to increase their abrasive effect, then cooling the braze with the reoriented diamond particles until it resolidifies.
    Type: Grant
    Filed: October 3, 1988
    Date of Patent: March 31, 1992
    Inventor: Ronald C. Wiand
  • Patent number: 5065933
    Abstract: A robotically controlled pick-uo to tool (11) is modified by connecting to it a load cell (26) that generates a signal indicative of stress on the pick-up tool. The pick-up tool is directed toward a chip (12) to be removed and movement is stopped when the load cell generates a first signal indicative of a first level of stress. In addition to stopping movement of the pick-up tool, the first signal actuates heating of the tool to a temperature sufficient to melt the solder (13) bonding the chip to the substrate (14). The melting of the solder bonds (13) results in a reduction of stress on the tool, which causes the load cell (26) to generate a signal indicative of the second level of stress. The second signal actuates the vacuum of the pick-up tool to cause adhesion of the chip to the pick-up tool and also initiates movement of the pick-up tool so as remove the chip from the substrate.
    Type: Grant
    Filed: September 19, 1990
    Date of Patent: November 19, 1991
    Assignee: AT&T Bell Laboratories
    Inventor: Nagesh R. Basavanhally
  • Patent number: 5054681
    Abstract: A tool for desoldering quadrilateral surface-mount components such as integrated circuits which have a row of leads on each of the four sides, the tool comprising a metallic hood with a depending skirt which contacts the rows of leads when the hood is snapped over the component. The hood is heated with a hot air gun or a heating element, and conducts the heat to the leads, melting the solder connecting the leads to the pads of the circuit board, permitting the component to be lifted off of the circuit board.
    Type: Grant
    Filed: July 25, 1990
    Date of Patent: October 8, 1991
    Inventor: Henry I. Kim
  • Patent number: 4980965
    Abstract: A method for winding a soft-magnetic ribbon to form a self-contained magnetic core using a winding arbor includes the step of, after the ribbon has been wound on the arbor, holding the free end of the ribbon to the preceding turn by spot welds, disposed in general alignment along a center of the ribbon. The free end of the ribbon may be tapered, so that projecting corners are avoided. By making the spot welds substantially in the center of the ribbon, the formation of eddy currents, which may occur if the spot weld accidentally connected two adjacent turns of the ribbon, are avoided. A similar method may be used to releasably attach the beginning of the ribbon to the arbor, with the spot welds then being broken when the core is removed from the arbor. The method is particularly suited for winding a ribbon consisting of amorphous soft-magnetic material.
    Type: Grant
    Filed: January 26, 1990
    Date of Patent: January 1, 1991
    Assignee: Vacuumschmelze GmbH
    Inventors: Reiner Dinter, Ewald Hientzsch, Karl-Friedrich Daus
  • Patent number: 4962879
    Abstract: A method for bubble-free bonding of silicon wafers to silicon wafers or silicon wafers to quartz wafers either outside or inside a Clean Room. The method includes the steps of positioning wafers in closely spaced-apart and parallel relationship to each other in a rack or the like with mirror-polished surfaces of the wafers facing each other, cleansing the mirror-polished surfaces with a hydrophilization cleansing solution, flushing the cleansing solution from the mirror-polished surfaces of the wafers with deionized water, drying the wafers in a spin-dryer, and moving the wafers together so that contact occurs between opposing mirror-polished surfaces of the wafers and bonding occurs. The bonded wafers are then placed into a wafer shipping and storing container for improved wafer storage performance.
    Type: Grant
    Filed: September 25, 1989
    Date of Patent: October 16, 1990
    Assignee: Duke University
    Inventors: Ulrich M. Goesele, Volker Lehmann
  • Patent number: 4942997
    Abstract: A solder well configured to abut and enclose the though hole pattern on a printed circuit board to allow the reflow of solder and removal of a multipin electronic component without affecting the integrity of adjacent solder joints of components disposed within or adjacent the through hole pattern.
    Type: Grant
    Filed: September 3, 1987
    Date of Patent: July 24, 1990
    Assignee: Ford Motor Company
    Inventors: Peter J. Sinkunas, Rodney L. Ritter, James E. Altpeter
  • Patent number: 4934582
    Abstract: A method and apparatus are described for the removal of solder mounted surface mount electronic components which includes the removal of old solder, broken leads, and the electronic component without damaging other devices on the substrate. A desoldering braid is shaped to cover each of the electronic component's outer lead bonds without contacting the component's base. The desoldering braid is heated and brought in contact with the bonds until the solder flows into the desoldering braid and any broken outer leads attach to the desoldering braid. Upon removal of the desoldering braid the electronic component can be lifted off the surface. The desoldered solder joints will contain a thin uniform coating of solder less than approximately 50 micro inches thick. This allows for removal and replacement of solder mounted electronic components with leads on center lines spaced less than 0.020 inches.
    Type: Grant
    Filed: September 20, 1989
    Date of Patent: June 19, 1990
    Assignee: Microelectronics and Computer Technology Corporation
    Inventors: Michael J. Bertram, Daniel M. Andrews
  • Patent number: 4909428
    Abstract: A furnace for soldering integrated circuit chips on a ceramic substrate has a heating plate supporting the substrate, the plate comprising perforations at the places where the integrated circuit chips will be soldered, behind the plate, a heat radiation source and a device to direct the radiation as desired towards only one of the apertures of the plate at a time.
    Type: Grant
    Filed: July 22, 1988
    Date of Patent: March 20, 1990
    Assignee: Thomson Composants Militaires et Spatiaux
    Inventor: Michel Mermet-Guyennet
  • Patent number: 4828162
    Abstract: Apparatus for gripping and removing integrated circuits, including four heatable jaws movable into gripping relation with soldered integrated circuit leads. The heatable jaws are mounted to respective leveler plates, each of which is suspended from a base member by a pivotable gripper arm and three flexure arms. Individual air cylinders are selectively actuable to pivot the gripper arms and thereby achieve inward motion and gripping action of the jaws. A second embodiment employs a cam follower mechanism rather than air cylinders to actuate similarly-mounted jaw elements.
    Type: Grant
    Filed: February 29, 1988
    Date of Patent: May 9, 1989
    Assignee: Hughes Aircraft Company
    Inventors: Joseph E. Donner, Wayne P. Jensen
  • Patent number: 4819990
    Abstract: A floor cutter for a plough has a component provided with cutting edges fixed by welding to a main body locating in a holder. The components are connected together with step-like surfaces chamfered at the external faces of the components to faciliate the welding. Superimposed support surfaces extend more or less normally to other surfaces and permit adjustment of the position of the components during welding to vary the set cutting depth.
    Type: Grant
    Filed: November 2, 1987
    Date of Patent: April 11, 1989
    Assignee: Gewerkschaft Eisenhutte Westfallia GmbH
    Inventors: Oswald Breuer, Christoph Rassmann, Egon Pfefferle, Gunther-Dietmar Schoop
  • Patent number: 4799617
    Abstract: A convection heat attachment and removal system for surface mounted assemblies is disclosed which uses a flow of heated gas to heat and melt solder contacts between surface mounted components and printed circuit boards. The system protects components adjacent to the workpiece by confining the flow of hot gas within a nozzle conduit which encompasses the workpiece. The system also protects the workpiece from overheating and thermal shock by shielding the workpiece from direct incidence of hot gas and by cooling the top surface of the workpiece with cool air. Relative positioning of the workpiece, the printed circuit board and the source of convection heat is accomplished by an arm mechanism as well as an X-Y table. The positioning means in this system are designed to accommodate a method of precise positioning disclosed herein. Convenient physical and visual access is provided to the workpiece and its location on the printed circuit board at any time during positioning.
    Type: Grant
    Filed: October 9, 1987
    Date of Patent: January 24, 1989
    Assignee: Advanced Techniques Co., Inc.
    Inventor: Gennady Friedman
  • Patent number: 4782991
    Abstract: A solder reflow machine for removing and replacing electronic components of the pin-grid array type having a large number of leads soldered into a very densely populated printed circuit board. The machine utilizes a heat-transfer liquid and a vacuum to remove the component from the board. The printed circuit board is positioned with the component facing downwardly. A tank containing the heat-transfer liquid is located below the printed circuit board. The apparatus includes a solder reflow head which has a component-engaging vacuum plate with a central opening that is in communication with a vacuum source through a pipe which is pulled downwardly to remove the component. The component is surrounded by a wall in combination with the bottom of the printed circuit board and seals off the liquid flow path.
    Type: Grant
    Filed: November 24, 1987
    Date of Patent: November 8, 1988
    Assignee: Unisys Corporation
    Inventor: Dennis L. Breu
  • Patent number: 4779790
    Abstract: Apparatus for performing an operation with molten solder, such as soldering or desoldering a component mounted on a substrate such as a PCB including an enclosed reservoir, the reservoir including a contained space above the molten solder; a hollow nozzle for receiving solder from the reservoir; an element for conveying the molten solder in the reservoir to the nozzle; and a source connected to the contained space for introducing a pressurized gas into the space to raise the solder through the conveying means to a predetermined level within the nozzle and maintaining said solder at said predetermined level to thus effect the operation with the molten solder and then removing the gas to return the solder to the reservoir. The gas is pulsed at least during the time the solder approaches and reaches the predetermined level. The apparatus includes a plurality of different size hollow nozzles for receiving solder from the reservoir where the nozzles are removably attachable with respect to the reservoir.
    Type: Grant
    Filed: December 11, 1986
    Date of Patent: October 25, 1988
    Assignee: Pace Incorporated
    Inventors: Linus E. Wallgren, Ararat Amirian, William J. Siegel
  • Patent number: 4768698
    Abstract: A X-Y table is disclosed having a table rotatably mounted on a base for movement in the X-Y and .theta. directions. The device includes fine adjustments in both X and Y directions and a quick shear mechanism with means for automatically returning the table to its original position after the quick shear procedure. The table may be used as a stand above unit or particularly for use in installing and removing components from printed circuit boards.
    Type: Grant
    Filed: October 3, 1986
    Date of Patent: September 6, 1988
    Assignee: Pace Incorporated
    Inventors: Robert G. Brown, Robert S. Quasney, William J. Siegel, Louis A. Abbagnaro
  • Patent number: 4768699
    Abstract: A desoldering method and apparatus for removal of molten solder from joined parts including a desoldering tool; a vacuum pump connected to the desoldering tool for applying vacuum thereto for removing the solder; a motor for energizing the pump; and circuitry for providing an initial, relatively high, voltage to the motor and for thereafter providing a relatively lower voltage to the motor so that, during the application of the high voltage to the motor, a relatively large pulse of the vacuum is applied to the joined parts to (a) effect removal of substantially all of the molten solder into the desoldering tool and (b) initiate cooldown of the parts and, during the application of the lower voltage to the motor, a relatively lower vacuum is continuously applied to maintain the cooldown of the parts.
    Type: Grant
    Filed: November 6, 1987
    Date of Patent: September 6, 1988
    Assignee: Pace Incorporated
    Inventor: Louis A. Abbagnaro
  • Patent number: 4767047
    Abstract: A device for removing a component from a substrate to which it is secured by solder. The device has a moveable member which defines a space to which suction can be applied. The space has an opening which can be positioned against the component so as to hold the latter to the moveable member by suction. Provision is made for applying heat to the solder to soften it. The moveable member is arranged such that the suction causes it to pull the component so as to remove it from the substrate when the solder is molten.
    Type: Grant
    Filed: January 29, 1987
    Date of Patent: August 30, 1988
    Assignee: The General Electric Company, p.l.c.
    Inventors: Richard I. Todd, Robert C. Claydon
  • Patent number: 4759491
    Abstract: A controlled amount of a solder is applied to the tip (18) of each lead (14) of a multi-lead component (10) by first placing a solder sphere (30) in each of a plurality of cavities (24) arranged in a baseplate (22) in the same pattern as the tips of the leads. Thereafter, the tips of the leads of the component are placed in contact with the solder spheres while, at the same time, at least a pair of leads are each engaged by a separate one of a pair of alignment pins (32) rising upwardly from the baseplate. The alignment pins serve to constrain the lateral movement of the component, thereby maintaining the leads thereof in alignment with the solder spheres when the solder spheres are reflowed to bond to the tips of the leads.
    Type: Grant
    Filed: May 18, 1987
    Date of Patent: July 26, 1988
    Assignee: American Telephone and Telegraph Company
    Inventor: John R. Fisher
  • Patent number: 4752025
    Abstract: A repair terminal is disclosed for reworking defective components on printed circuit boards. The terminal has a heater arm which lowers itself over the component, and directs hot gas thereon. A vacuum shroud surrounds the heat zone around the component and removes excess heat so as to minimize damage to surrounding components. The heater arm has inner and outer tubes, the inner tube delivering hot gas the outer tube removing it. Thus the outer tube prevents an operator from being burned by the dangerously hot temperature of the inner tube. A workholder is also disclosed for holding and aligning the circuit board with the heater arm. The workholder is capable of adjustment along the X- and Y-axes as well as in the theta orientation.
    Type: Grant
    Filed: May 22, 1987
    Date of Patent: June 21, 1988
    Assignee: Austin American Technology
    Inventors: Steven R. Stach, Carl R. Scrogum
  • Patent number: 4750664
    Abstract: The present invention proposes an apparatus or jig for the controlled spot heating of a substrate having soldered components therein and a designated locus to be heated for removal and/or replacement of a component. The apparatus comprises a frame and support means on the frame for holding and positioning the substrate with the locus to be heated along a designated axis of the frame. A rail at one end of the frame parallel to the designated axis holds a heating arm. The heating arm extends along an axis perpendicular to the designated axis and can be positioned along the rail. The heating arm ends in a directing means that is positioned over the designated axis and directs a heating medium, e.g. infra red radiation or a heated gas, onto a locus to be heated. The directing means limits the area of the application of the heating medium to only that area necessary for removal of the component.
    Type: Grant
    Filed: July 20, 1987
    Date of Patent: June 14, 1988
    Inventor: Edward J. Furtek
  • Patent number: 4740099
    Abstract: A method is provided of temporary assembling by soldering of peel off plates through soldering material and a flexible junction element for a mechanical release device to release two parts temporarily fixed edgewise by peeling off the flexible element and the soldering material. There is provided on the plates and flexible junction element reserve areas without any adherence to the soldering material, and preferably at the limits of said reserved areas a recess for removing any excess of soldering material, and the melting solder material is put under load for distributing it between the plates and the flexible junction element. A so obtained assembly can be applied particularly to obtain automatic opening of containers in particular in space for spreading out solar panels.
    Type: Grant
    Filed: May 2, 1986
    Date of Patent: April 26, 1988
    Assignee: Societe Nationale Industrielle Aerospatiale
    Inventor: Jean-Pierre Philipoussi
  • Patent number: 4693658
    Abstract: The disclosure relates to a method of manufacturing a body formed of a shaped sheet metal blank having an opening tear strip terminating in a tongue. Overlapping edges of the blank are welded together and at the tear strip melting of a tin coating of the blank occurs so that at the tear strip the edges of the blank are linked by melted tin, or welding is completely interrupted to form a slot at the tear strip between the overlapping edges of the blank and the slot using a sealing material. Further, the disclosure relates to a metal blank for a can body having a tear strip formed there across by two weakening scores extending transversely to the edges of the blank and terminating in a tongue. The tear strip at one of the edges of the blank is provided with a covering and/or oxide layer which has a relatively low electrical conductivity.
    Type: Grant
    Filed: June 18, 1985
    Date of Patent: September 15, 1987
    Assignee: Thomassen & Drijver-Verblifa NV
    Inventors: Johannes A. Glerum, Robert C. Klunder