WO2020082092A1 - Precision chip bonding by adhesive wicking - Google Patents

Precision chip bonding by adhesive wicking Download PDF

Info

Publication number
WO2020082092A1
WO2020082092A1 PCT/US2019/057575 US2019057575W WO2020082092A1 WO 2020082092 A1 WO2020082092 A1 WO 2020082092A1 US 2019057575 W US2019057575 W US 2019057575W WO 2020082092 A1 WO2020082092 A1 WO 2020082092A1
Authority
WO
WIPO (PCT)
Prior art keywords
substrate
adhesive
contact
applying
pedestal
Prior art date
Application number
PCT/US2019/057575
Other languages
French (fr)
Inventor
Lei Wang
Original Assignee
Futurewei Technologies, Inc.
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Futurewei Technologies, Inc. filed Critical Futurewei Technologies, Inc.
Priority to PCT/US2019/057575 priority Critical patent/WO2020082092A1/en
Publication of WO2020082092A1 publication Critical patent/WO2020082092A1/en

Links

Classifications

    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
    • H01L24/00—Arrangements for connecting or disconnecting semiconductor or solid-state bodies; Methods or apparatus related thereto
    • H01L24/01—Means for bonding being attached to, or being formed on, the surface to be connected, e.g. chip-to-package, die-attach, "first-level" interconnects; Manufacturing methods related thereto
    • H01L24/26—Layer connectors, e.g. plate connectors, solder or adhesive layers; Manufacturing methods related thereto
    • H01L24/27—Manufacturing methods
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B23—MACHINE TOOLS; METAL-WORKING NOT OTHERWISE PROVIDED FOR
    • B23K—SOLDERING OR UNSOLDERING; WELDING; CLADDING OR PLATING BY SOLDERING OR WELDING; CUTTING BY APPLYING HEAT LOCALLY, e.g. FLAME CUTTING; WORKING BY LASER BEAM
    • B23K1/00—Soldering, e.g. brazing, or unsoldering
    • B23K1/0004—Resistance soldering
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B23—MACHINE TOOLS; METAL-WORKING NOT OTHERWISE PROVIDED FOR
    • B23K—SOLDERING OR UNSOLDERING; WELDING; CLADDING OR PLATING BY SOLDERING OR WELDING; CUTTING BY APPLYING HEAT LOCALLY, e.g. FLAME CUTTING; WORKING BY LASER BEAM
    • B23K1/00—Soldering, e.g. brazing, or unsoldering
    • B23K1/0008—Soldering, e.g. brazing, or unsoldering specially adapted for particular articles or work
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B23—MACHINE TOOLS; METAL-WORKING NOT OTHERWISE PROVIDED FOR
    • B23K—SOLDERING OR UNSOLDERING; WELDING; CLADDING OR PLATING BY SOLDERING OR WELDING; CUTTING BY APPLYING HEAT LOCALLY, e.g. FLAME CUTTING; WORKING BY LASER BEAM
    • B23K1/00—Soldering, e.g. brazing, or unsoldering
    • B23K1/005—Soldering by means of radiant energy
    • B23K1/0056—Soldering by means of radiant energy soldering by means of beams, e.g. lasers, E.B.
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
    • H01L24/00—Arrangements for connecting or disconnecting semiconductor or solid-state bodies; Methods or apparatus related thereto
    • H01L24/01—Means for bonding being attached to, or being formed on, the surface to be connected, e.g. chip-to-package, die-attach, "first-level" interconnects; Manufacturing methods related thereto
    • H01L24/26—Layer connectors, e.g. plate connectors, solder or adhesive layers; Manufacturing methods related thereto
    • H01L24/28—Structure, shape, material or disposition of the layer connectors prior to the connecting process
    • H01L24/29—Structure, shape, material or disposition of the layer connectors prior to the connecting process of an individual layer connector
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
    • H01L24/00—Arrangements for connecting or disconnecting semiconductor or solid-state bodies; Methods or apparatus related thereto
    • H01L24/01—Means for bonding being attached to, or being formed on, the surface to be connected, e.g. chip-to-package, die-attach, "first-level" interconnects; Manufacturing methods related thereto
    • H01L24/26—Layer connectors, e.g. plate connectors, solder or adhesive layers; Manufacturing methods related thereto
    • H01L24/28—Structure, shape, material or disposition of the layer connectors prior to the connecting process
    • H01L24/30—Structure, shape, material or disposition of the layer connectors prior to the connecting process of a plurality of layer connectors
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
    • H01L24/00—Arrangements for connecting or disconnecting semiconductor or solid-state bodies; Methods or apparatus related thereto
    • H01L24/80—Methods for connecting semiconductor or other solid state bodies using means for bonding being attached to, or being formed on, the surface to be connected
    • H01L24/83—Methods for connecting semiconductor or other solid state bodies using means for bonding being attached to, or being formed on, the surface to be connected using a layer connector
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B32—LAYERED PRODUCTS
    • B32B—LAYERED PRODUCTS, i.e. PRODUCTS BUILT-UP OF STRATA OF FLAT OR NON-FLAT, e.g. CELLULAR OR HONEYCOMB, FORM
    • B32B37/00—Methods or apparatus for laminating, e.g. by curing or by ultrasonic bonding
    • B32B37/12—Methods or apparatus for laminating, e.g. by curing or by ultrasonic bonding characterised by using adhesives
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B32—LAYERED PRODUCTS
    • B32B—LAYERED PRODUCTS, i.e. PRODUCTS BUILT-UP OF STRATA OF FLAT OR NON-FLAT, e.g. CELLULAR OR HONEYCOMB, FORM
    • B32B38/00—Ancillary operations in connection with laminating processes
    • B32B38/18—Handling of layers or the laminate
    • B32B38/1825—Handling of layers or the laminate characterised by the control or constructional features of devices for tensioning, stretching or registration
    • B32B38/1833—Positioning, e.g. registration or centering
    • B32B38/1841—Positioning, e.g. registration or centering during laying up
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
    • F16B—DEVICES FOR FASTENING OR SECURING CONSTRUCTIONAL ELEMENTS OR MACHINE PARTS TOGETHER, e.g. NAILS, BOLTS, CIRCLIPS, CLAMPS, CLIPS OR WEDGES; JOINTS OR JOINTING
    • F16B11/00—Connecting constructional elements or machine parts by sticking or pressing them together, e.g. cold pressure welding
    • F16B11/006—Connecting constructional elements or machine parts by sticking or pressing them together, e.g. cold pressure welding by gluing
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
    • H01L2224/00—Indexing scheme for arrangements for connecting or disconnecting semiconductor or solid-state bodies and methods related thereto as covered by H01L24/00
    • H01L2224/01—Means for bonding being attached to, or being formed on, the surface to be connected, e.g. chip-to-package, die-attach, "first-level" interconnects; Manufacturing methods related thereto
    • H01L2224/26—Layer connectors, e.g. plate connectors, solder or adhesive layers; Manufacturing methods related thereto
    • H01L2224/27—Manufacturing methods
    • H01L2224/273—Manufacturing methods by local deposition of the material of the layer connector
    • H01L2224/2731—Manufacturing methods by local deposition of the material of the layer connector in liquid form
    • H01L2224/27318—Manufacturing methods by local deposition of the material of the layer connector in liquid form by dispensing droplets
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
    • H01L2224/00—Indexing scheme for arrangements for connecting or disconnecting semiconductor or solid-state bodies and methods related thereto as covered by H01L24/00
    • H01L2224/01—Means for bonding being attached to, or being formed on, the surface to be connected, e.g. chip-to-package, die-attach, "first-level" interconnects; Manufacturing methods related thereto
    • H01L2224/26—Layer connectors, e.g. plate connectors, solder or adhesive layers; Manufacturing methods related thereto
    • H01L2224/27—Manufacturing methods
    • H01L2224/273—Manufacturing methods by local deposition of the material of the layer connector
    • H01L2224/2733—Manufacturing methods by local deposition of the material of the layer connector in solid form
    • H01L2224/27334—Manufacturing methods by local deposition of the material of the layer connector in solid form using preformed layer
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
    • H01L2224/00—Indexing scheme for arrangements for connecting or disconnecting semiconductor or solid-state bodies and methods related thereto as covered by H01L24/00
    • H01L2224/01—Means for bonding being attached to, or being formed on, the surface to be connected, e.g. chip-to-package, die-attach, "first-level" interconnects; Manufacturing methods related thereto
    • H01L2224/26—Layer connectors, e.g. plate connectors, solder or adhesive layers; Manufacturing methods related thereto
    • H01L2224/27—Manufacturing methods
    • H01L2224/274—Manufacturing methods by blanket deposition of the material of the layer connector
    • H01L2224/27444—Manufacturing methods by blanket deposition of the material of the layer connector in gaseous form
    • H01L2224/2745—Physical vapour deposition [PVD], e.g. evaporation, or sputtering
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
    • H01L2224/00—Indexing scheme for arrangements for connecting or disconnecting semiconductor or solid-state bodies and methods related thereto as covered by H01L24/00
    • H01L2224/01—Means for bonding being attached to, or being formed on, the surface to be connected, e.g. chip-to-package, die-attach, "first-level" interconnects; Manufacturing methods related thereto
    • H01L2224/26—Layer connectors, e.g. plate connectors, solder or adhesive layers; Manufacturing methods related thereto
    • H01L2224/27—Manufacturing methods
    • H01L2224/2747—Manufacturing methods using a lift-off mask
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
    • H01L2224/00—Indexing scheme for arrangements for connecting or disconnecting semiconductor or solid-state bodies and methods related thereto as covered by H01L24/00
    • H01L2224/01—Means for bonding being attached to, or being formed on, the surface to be connected, e.g. chip-to-package, die-attach, "first-level" interconnects; Manufacturing methods related thereto
    • H01L2224/26—Layer connectors, e.g. plate connectors, solder or adhesive layers; Manufacturing methods related thereto
    • H01L2224/28—Structure, shape, material or disposition of the layer connectors prior to the connecting process
    • H01L2224/29—Structure, shape, material or disposition of the layer connectors prior to the connecting process of an individual layer connector
    • H01L2224/29001—Core members of the layer connector
    • H01L2224/2901—Shape
    • H01L2224/29012—Shape in top view
    • H01L2224/29013—Shape in top view being rectangular or square
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
    • H01L2224/00—Indexing scheme for arrangements for connecting or disconnecting semiconductor or solid-state bodies and methods related thereto as covered by H01L24/00
    • H01L2224/01—Means for bonding being attached to, or being formed on, the surface to be connected, e.g. chip-to-package, die-attach, "first-level" interconnects; Manufacturing methods related thereto
    • H01L2224/26—Layer connectors, e.g. plate connectors, solder or adhesive layers; Manufacturing methods related thereto
    • H01L2224/28—Structure, shape, material or disposition of the layer connectors prior to the connecting process
    • H01L2224/29—Structure, shape, material or disposition of the layer connectors prior to the connecting process of an individual layer connector
    • H01L2224/29001—Core members of the layer connector
    • H01L2224/29099—Material
    • H01L2224/291—Material with a principal constituent of the material being a metal or a metalloid, e.g. boron [B], silicon [Si], germanium [Ge], arsenic [As], antimony [Sb], tellurium [Te] and polonium [Po], and alloys thereof
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
    • H01L2224/00—Indexing scheme for arrangements for connecting or disconnecting semiconductor or solid-state bodies and methods related thereto as covered by H01L24/00
    • H01L2224/01—Means for bonding being attached to, or being formed on, the surface to be connected, e.g. chip-to-package, die-attach, "first-level" interconnects; Manufacturing methods related thereto
    • H01L2224/26—Layer connectors, e.g. plate connectors, solder or adhesive layers; Manufacturing methods related thereto
    • H01L2224/28—Structure, shape, material or disposition of the layer connectors prior to the connecting process
    • H01L2224/29—Structure, shape, material or disposition of the layer connectors prior to the connecting process of an individual layer connector
    • H01L2224/29001—Core members of the layer connector
    • H01L2224/29099—Material
    • H01L2224/2919—Material with a principal constituent of the material being a polymer, e.g. polyester, phenolic based polymer, epoxy
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
    • H01L2224/00—Indexing scheme for arrangements for connecting or disconnecting semiconductor or solid-state bodies and methods related thereto as covered by H01L24/00
    • H01L2224/01—Means for bonding being attached to, or being formed on, the surface to be connected, e.g. chip-to-package, die-attach, "first-level" interconnects; Manufacturing methods related thereto
    • H01L2224/26—Layer connectors, e.g. plate connectors, solder or adhesive layers; Manufacturing methods related thereto
    • H01L2224/28—Structure, shape, material or disposition of the layer connectors prior to the connecting process
    • H01L2224/30—Structure, shape, material or disposition of the layer connectors prior to the connecting process of a plurality of layer connectors
    • H01L2224/301—Disposition
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
    • H01L2224/00—Indexing scheme for arrangements for connecting or disconnecting semiconductor or solid-state bodies and methods related thereto as covered by H01L24/00
    • H01L2224/01—Means for bonding being attached to, or being formed on, the surface to be connected, e.g. chip-to-package, die-attach, "first-level" interconnects; Manufacturing methods related thereto
    • H01L2224/26—Layer connectors, e.g. plate connectors, solder or adhesive layers; Manufacturing methods related thereto
    • H01L2224/28—Structure, shape, material or disposition of the layer connectors prior to the connecting process
    • H01L2224/30—Structure, shape, material or disposition of the layer connectors prior to the connecting process of a plurality of layer connectors
    • H01L2224/301—Disposition
    • H01L2224/30104—Disposition relative to the bonding areas, e.g. bond pads, of the semiconductor or solid-state body
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
    • H01L2224/00—Indexing scheme for arrangements for connecting or disconnecting semiconductor or solid-state bodies and methods related thereto as covered by H01L24/00
    • H01L2224/01—Means for bonding being attached to, or being formed on, the surface to be connected, e.g. chip-to-package, die-attach, "first-level" interconnects; Manufacturing methods related thereto
    • H01L2224/26—Layer connectors, e.g. plate connectors, solder or adhesive layers; Manufacturing methods related thereto
    • H01L2224/28—Structure, shape, material or disposition of the layer connectors prior to the connecting process
    • H01L2224/30—Structure, shape, material or disposition of the layer connectors prior to the connecting process of a plurality of layer connectors
    • H01L2224/301—Disposition
    • H01L2224/3012—Layout
    • H01L2224/3015—Mirror array, i.e. array having only a reflection symmetry, i.e. bilateral symmetry
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
    • H01L2224/00—Indexing scheme for arrangements for connecting or disconnecting semiconductor or solid-state bodies and methods related thereto as covered by H01L24/00
    • H01L2224/01—Means for bonding being attached to, or being formed on, the surface to be connected, e.g. chip-to-package, die-attach, "first-level" interconnects; Manufacturing methods related thereto
    • H01L2224/26—Layer connectors, e.g. plate connectors, solder or adhesive layers; Manufacturing methods related thereto
    • H01L2224/31—Structure, shape, material or disposition of the layer connectors after the connecting process
    • H01L2224/32—Structure, shape, material or disposition of the layer connectors after the connecting process of an individual layer connector
    • H01L2224/321—Disposition
    • H01L2224/32151—Disposition the layer connector connecting between a semiconductor or solid-state body and an item not being a semiconductor or solid-state body, e.g. chip-to-substrate, chip-to-passive
    • H01L2224/32221—Disposition the layer connector connecting between a semiconductor or solid-state body and an item not being a semiconductor or solid-state body, e.g. chip-to-substrate, chip-to-passive the body and the item being stacked
    • H01L2224/32225—Disposition the layer connector connecting between a semiconductor or solid-state body and an item not being a semiconductor or solid-state body, e.g. chip-to-substrate, chip-to-passive the body and the item being stacked the item being non-metallic, e.g. insulating substrate with or without metallisation
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
    • H01L2224/00—Indexing scheme for arrangements for connecting or disconnecting semiconductor or solid-state bodies and methods related thereto as covered by H01L24/00
    • H01L2224/01—Means for bonding being attached to, or being formed on, the surface to be connected, e.g. chip-to-package, die-attach, "first-level" interconnects; Manufacturing methods related thereto
    • H01L2224/26—Layer connectors, e.g. plate connectors, solder or adhesive layers; Manufacturing methods related thereto
    • H01L2224/31—Structure, shape, material or disposition of the layer connectors after the connecting process
    • H01L2224/32—Structure, shape, material or disposition of the layer connectors after the connecting process of an individual layer connector
    • H01L2224/321—Disposition
    • H01L2224/32151—Disposition the layer connector connecting between a semiconductor or solid-state body and an item not being a semiconductor or solid-state body, e.g. chip-to-substrate, chip-to-passive
    • H01L2224/32221—Disposition the layer connector connecting between a semiconductor or solid-state body and an item not being a semiconductor or solid-state body, e.g. chip-to-substrate, chip-to-passive the body and the item being stacked
    • H01L2224/32225—Disposition the layer connector connecting between a semiconductor or solid-state body and an item not being a semiconductor or solid-state body, e.g. chip-to-substrate, chip-to-passive the body and the item being stacked the item being non-metallic, e.g. insulating substrate with or without metallisation
    • H01L2224/32237—Disposition the layer connector connecting between a semiconductor or solid-state body and an item not being a semiconductor or solid-state body, e.g. chip-to-substrate, chip-to-passive the body and the item being stacked the item being non-metallic, e.g. insulating substrate with or without metallisation the layer connector connecting to a bonding area disposed in a recess of the surface of the item
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
    • H01L2224/00—Indexing scheme for arrangements for connecting or disconnecting semiconductor or solid-state bodies and methods related thereto as covered by H01L24/00
    • H01L2224/80—Methods for connecting semiconductor or other solid state bodies using means for bonding being attached to, or being formed on, the surface to be connected
    • H01L2224/83—Methods for connecting semiconductor or other solid state bodies using means for bonding being attached to, or being formed on, the surface to be connected using a layer connector
    • H01L2224/83007—Methods for connecting semiconductor or other solid state bodies using means for bonding being attached to, or being formed on, the surface to be connected using a layer connector involving a permanent auxiliary member being left in the finished device, e.g. aids for holding or protecting the layer connector during or after the bonding process
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
    • H01L2224/00—Indexing scheme for arrangements for connecting or disconnecting semiconductor or solid-state bodies and methods related thereto as covered by H01L24/00
    • H01L2224/80—Methods for connecting semiconductor or other solid state bodies using means for bonding being attached to, or being formed on, the surface to be connected
    • H01L2224/83—Methods for connecting semiconductor or other solid state bodies using means for bonding being attached to, or being formed on, the surface to be connected using a layer connector
    • H01L2224/831—Methods for connecting semiconductor or other solid state bodies using means for bonding being attached to, or being formed on, the surface to be connected using a layer connector the layer connector being supplied to the parts to be connected in the bonding apparatus
    • H01L2224/83102—Methods for connecting semiconductor or other solid state bodies using means for bonding being attached to, or being formed on, the surface to be connected using a layer connector the layer connector being supplied to the parts to be connected in the bonding apparatus using surface energy, e.g. capillary forces
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
    • H01L2224/00—Indexing scheme for arrangements for connecting or disconnecting semiconductor or solid-state bodies and methods related thereto as covered by H01L24/00
    • H01L2224/80—Methods for connecting semiconductor or other solid state bodies using means for bonding being attached to, or being formed on, the surface to be connected
    • H01L2224/83—Methods for connecting semiconductor or other solid state bodies using means for bonding being attached to, or being formed on, the surface to be connected using a layer connector
    • H01L2224/8312—Aligning
    • H01L2224/83136—Aligning involving guiding structures, e.g. spacers or supporting members
    • H01L2224/83138—Aligning involving guiding structures, e.g. spacers or supporting members the guiding structures being at least partially left in the finished device
    • H01L2224/83139—Guiding structures on the body
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
    • H01L2224/00—Indexing scheme for arrangements for connecting or disconnecting semiconductor or solid-state bodies and methods related thereto as covered by H01L24/00
    • H01L2224/80—Methods for connecting semiconductor or other solid state bodies using means for bonding being attached to, or being formed on, the surface to be connected
    • H01L2224/83—Methods for connecting semiconductor or other solid state bodies using means for bonding being attached to, or being formed on, the surface to be connected using a layer connector
    • H01L2224/8312—Aligning
    • H01L2224/83136—Aligning involving guiding structures, e.g. spacers or supporting members
    • H01L2224/83138—Aligning involving guiding structures, e.g. spacers or supporting members the guiding structures being at least partially left in the finished device
    • H01L2224/8314—Guiding structures outside the body
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
    • H01L2224/00—Indexing scheme for arrangements for connecting or disconnecting semiconductor or solid-state bodies and methods related thereto as covered by H01L24/00
    • H01L2224/80—Methods for connecting semiconductor or other solid state bodies using means for bonding being attached to, or being formed on, the surface to be connected
    • H01L2224/83—Methods for connecting semiconductor or other solid state bodies using means for bonding being attached to, or being formed on, the surface to be connected using a layer connector
    • H01L2224/8312—Aligning
    • H01L2224/83136—Aligning involving guiding structures, e.g. spacers or supporting members
    • H01L2224/83138—Aligning involving guiding structures, e.g. spacers or supporting members the guiding structures being at least partially left in the finished device
    • H01L2224/83141—Guiding structures both on and outside the body
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
    • H01L2224/00—Indexing scheme for arrangements for connecting or disconnecting semiconductor or solid-state bodies and methods related thereto as covered by H01L24/00
    • H01L2224/80—Methods for connecting semiconductor or other solid state bodies using means for bonding being attached to, or being formed on, the surface to be connected
    • H01L2224/83—Methods for connecting semiconductor or other solid state bodies using means for bonding being attached to, or being formed on, the surface to be connected using a layer connector
    • H01L2224/8319—Arrangement of the layer connectors prior to mounting
    • H01L2224/83192—Arrangement of the layer connectors prior to mounting wherein the layer connectors are disposed only on another item or body to be connected to the semiconductor or solid-state body
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
    • H01L2224/00—Indexing scheme for arrangements for connecting or disconnecting semiconductor or solid-state bodies and methods related thereto as covered by H01L24/00
    • H01L2224/80—Methods for connecting semiconductor or other solid state bodies using means for bonding being attached to, or being formed on, the surface to be connected
    • H01L2224/83—Methods for connecting semiconductor or other solid state bodies using means for bonding being attached to, or being formed on, the surface to be connected using a layer connector
    • H01L2224/832—Applying energy for connecting
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
    • H01L2224/00—Indexing scheme for arrangements for connecting or disconnecting semiconductor or solid-state bodies and methods related thereto as covered by H01L24/00
    • H01L2224/80—Methods for connecting semiconductor or other solid state bodies using means for bonding being attached to, or being formed on, the surface to be connected
    • H01L2224/83—Methods for connecting semiconductor or other solid state bodies using means for bonding being attached to, or being formed on, the surface to be connected using a layer connector
    • H01L2224/832—Applying energy for connecting
    • H01L2224/8322—Applying energy for connecting with energy being in the form of electromagnetic radiation
    • H01L2224/83224—Applying energy for connecting with energy being in the form of electromagnetic radiation using a laser
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
    • H01L2224/00—Indexing scheme for arrangements for connecting or disconnecting semiconductor or solid-state bodies and methods related thereto as covered by H01L24/00
    • H01L2224/80—Methods for connecting semiconductor or other solid state bodies using means for bonding being attached to, or being formed on, the surface to be connected
    • H01L2224/83—Methods for connecting semiconductor or other solid state bodies using means for bonding being attached to, or being formed on, the surface to be connected using a layer connector
    • H01L2224/832—Applying energy for connecting
    • H01L2224/83234—Applying energy for connecting using means for applying energy being within the device, e.g. integrated heater
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
    • H01L2224/00—Indexing scheme for arrangements for connecting or disconnecting semiconductor or solid-state bodies and methods related thereto as covered by H01L24/00
    • H01L2224/80—Methods for connecting semiconductor or other solid state bodies using means for bonding being attached to, or being formed on, the surface to be connected
    • H01L2224/83—Methods for connecting semiconductor or other solid state bodies using means for bonding being attached to, or being formed on, the surface to be connected using a layer connector
    • H01L2224/8336—Bonding interfaces of the semiconductor or solid state body
    • H01L2224/83365—Shape, e.g. interlocking features
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
    • H01L2224/00—Indexing scheme for arrangements for connecting or disconnecting semiconductor or solid-state bodies and methods related thereto as covered by H01L24/00
    • H01L2224/80—Methods for connecting semiconductor or other solid state bodies using means for bonding being attached to, or being formed on, the surface to be connected
    • H01L2224/83—Methods for connecting semiconductor or other solid state bodies using means for bonding being attached to, or being formed on, the surface to be connected using a layer connector
    • H01L2224/8338—Bonding interfaces outside the semiconductor or solid-state body
    • H01L2224/83385—Shape, e.g. interlocking features
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
    • H01L2224/00—Indexing scheme for arrangements for connecting or disconnecting semiconductor or solid-state bodies and methods related thereto as covered by H01L24/00
    • H01L2224/80—Methods for connecting semiconductor or other solid state bodies using means for bonding being attached to, or being formed on, the surface to be connected
    • H01L2224/83—Methods for connecting semiconductor or other solid state bodies using means for bonding being attached to, or being formed on, the surface to be connected using a layer connector
    • H01L2224/8338—Bonding interfaces outside the semiconductor or solid-state body
    • H01L2224/83395—Bonding interfaces outside the semiconductor or solid-state body having an external coating, e.g. protective bond-through coating
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
    • H01L2224/00—Indexing scheme for arrangements for connecting or disconnecting semiconductor or solid-state bodies and methods related thereto as covered by H01L24/00
    • H01L2224/80—Methods for connecting semiconductor or other solid state bodies using means for bonding being attached to, or being formed on, the surface to be connected
    • H01L2224/83—Methods for connecting semiconductor or other solid state bodies using means for bonding being attached to, or being formed on, the surface to be connected using a layer connector
    • H01L2224/8338—Bonding interfaces outside the semiconductor or solid-state body
    • H01L2224/83399—Material
    • H01L2224/834—Material with a principal constituent of the material being a metal or a metalloid, e.g. boron [B], silicon [Si], germanium [Ge], arsenic [As], antimony [Sb], tellurium [Te] and polonium [Po], and alloys thereof
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
    • H01L2224/00—Indexing scheme for arrangements for connecting or disconnecting semiconductor or solid-state bodies and methods related thereto as covered by H01L24/00
    • H01L2224/80—Methods for connecting semiconductor or other solid state bodies using means for bonding being attached to, or being formed on, the surface to be connected
    • H01L2224/83—Methods for connecting semiconductor or other solid state bodies using means for bonding being attached to, or being formed on, the surface to be connected using a layer connector
    • H01L2224/838—Bonding techniques
    • H01L2224/83801—Soldering or alloying
    • H01L2224/83815—Reflow soldering
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
    • H01L2224/00—Indexing scheme for arrangements for connecting or disconnecting semiconductor or solid-state bodies and methods related thereto as covered by H01L24/00
    • H01L2224/80—Methods for connecting semiconductor or other solid state bodies using means for bonding being attached to, or being formed on, the surface to be connected
    • H01L2224/83—Methods for connecting semiconductor or other solid state bodies using means for bonding being attached to, or being formed on, the surface to be connected using a layer connector
    • H01L2224/838—Bonding techniques
    • H01L2224/8385—Bonding techniques using a polymer adhesive, e.g. an adhesive based on silicone, epoxy, polyimide, polyester
    • H01L2224/83855—Hardening the adhesive by curing, i.e. thermosetting
    • H01L2224/83874—Ultraviolet [UV] curing

Definitions

  • Optical component assembly and packaging bonding usually requires precise alignment.
  • the tolerance for precise alignment includes below one-micrometer using submicron precision, for example.
  • Typical adhesive bonding processes involve sandwiching the adhesive between two parts to be bonded and introducing energy to solidify the adhesive thus bonding the two parts. Before its solidification, however, the adhesive may act as a lubricant and facilitate relative sliding between the two parts to be bonded. The relative sliding introduces misalignment during the adhesive bonding process.
  • optical component assembly and packaging primarily employs fixtures to provide mechanical constraints on the parts to be bonded. However, fixtures may undergo minute movements induced by thermal expansion, due to energy introduction, and the slippery liquid adhesive will exacerbate the movement that results in misalignment of parts after solidification of the adhesive.
  • the techniques of this specification address the slippery adhesive issue by ensuring the two parts to be bonded remain stationary with respect to each other during the adhesive solidification process.
  • at least a portion of both surfaces of the two parts to be bonded remains in direct contact without liquid intermediary, namely the adhesive prior to its solidification, throughout the bonding process.
  • the adhesive wicks into one or more gaps surrounding the contact portion between the two parts via a capillary force.
  • the adhesive wicks into the gaps this incurs an increased benefit of friction and ultimately, minimizes the sliding and improves the post bond alignment precision by reducing the amount of misalignment of parts during the solidification of the adhesive.
  • the parts are bonded together.
  • a method includes: aligning a first substrate to contact a second substrate; applying an adhesive to at least one top portion of the second substrate in proximity to a contact position between the first substrate and the second substrate; placing a first substrate in contact with a second substrate; and applying radiation to the adhesive, wherein applying the radiation to the adhesive causes the adhesive to wick into at least one gap formed in proximity to the contact position between the first substrate and the second substrate.
  • FIG. 1 A block diagram illustrating an exemplary computing environment in accordance with this and other aspects of the disclosure.
  • FIG. 1 A block diagram illustrating an exemplary computing environment in accordance with this disclosure.
  • FIG. 1 A block diagram illustrating an exemplary computing environment in accordance with this disclosure.
  • FIG. 1 A block diagram illustrating an exemplary computing environment in accordance with this disclosure.
  • FIG. 1 A block diagram illustrating an exemplary computing environment in accordance with this disclosure.
  • the second substrate includes an embedded trench at a center portion of the second substrate, and wherein aligning the first substrate to contact the second substrate, the method further includes: aligning the first substrate to contact the second substrate over the center portion; applying the adhesive to the at least one top portion of the second substrate in the embedded trench without contacting the first substrate; placing the first substrate to contact with the second substrate over the center portion; and applying the radiation to the adhesive causes the adhesive to wick into the at least one gap formed at the center portion in the embedded trench on the second substrate while maintaining alignment between the first and second substrates.
  • the method includes applying a primer to the second substrate for facilitating the adhesive to flow towards the at least one gap.
  • applying the adhesive to the at least one top portion of the second substrate further includes: applying the adhesive to the at least one top portion of the second substrate in proximity to the contact position between the first substrate and the second substrate without coming into contact with the first substrate.
  • applying the radiation to the adhesive causes the adhesive to wick into the at least one gap further includes: applying the radiation to the adhesive, wherein applying the radiation to the adhesive causes the adhesive to wick into the at least one gap formed between the contact position while maintaining in an alignment position created during alignment of the first substrate to contact the second substrate.
  • the second substrate includes at least one pedestal
  • placing the first substrate in contact with the second substrate includes placing the first substrate in contact with the second substrate at the at least one pedestal, and wherein a height Attorney Docket No. 41703-0041W01//86229795PCT02 of the at least one pedestal at the contact position defines a height of the at least one gap formed at the contact position between the first substrate and the second substrate.
  • the first substrate has a high friction surface
  • the second substrate has a high friction surface
  • placing the first substrate in contact with the second substrate includes applying the high friction surface of the first substrate to contact the high friction surface of the second substrate at the contact position, wherein the adhesive is not applied between the contact position.
  • the high friction surface includes a rough finish or a pattern or interlocking features.
  • the adhesive includes epoxy or solder.
  • the method further includes applying the adhesive to the at least one top portion of the second substrate after aligning and forming the first substrate to contact the second substrate.
  • the method when the adhesive is solder, the method further includes depositing the adhesive to the at least one top portion of the second substrate before aligning and forming the first substrate to contact the second substrate.
  • FIG. 1 is a block diagram that illustrates an example of a system bonding together substrates using pedestals between the substrates.
  • FIG. 2 is a block diagram that illustrates an example of a system bonding together substrates including a trench between the substrates.
  • FIG. 3 is a block diagram that illustrates an example of a system bonding together substrates including a non-uniform surface between the substrates.
  • FIG. 4 is a flow diagram that illustrates an example of a process for bonding together substrates and wicking adhesives between the substrates.
  • FIG. 5 is a flow diagram that illustrates an example of a process for bonding together substrates and wicking adhesive between the substrates.
  • Typical optical component assembly/packaging during an adhesive process requires precise alignment, e.g., often within a micrometer or less of error.
  • the optical components can incur misalignment during the adhesive process because adhesive can act as a lubricant and facilitate relative sliding between the optical components.
  • the relative sliding creates negative effects for the optical component assembly, such as a detrimental optical loss, a reduced electrical conductivity and an inoperable assembly package.
  • FIG. 1 is a block diagram that illustrates an example of a system 100 bonding together substrates using pedestals between the substrates.
  • the system 100 includes two substrates - substrate 102 and substrate 104 in three stages of manufacture illustrated as A, B and C.
  • the system 100 illustrates the process of aligning tow substrates together, applying an adhesive to the second substrate, placing a first substrate in contact with the second substrate, and applying radiation to the adhesive causing the adhesive to wick into a gap formed next to the contact position between the first and second substrate.
  • the substrates 102 and 104 can be composed of glass, silicon, polymer, hybrid components, and other components.
  • the system 100 also includes adhesive 106-A and 106-B deposited on a top portion of the substrate B 104.
  • the adhesive can be deposited as epoxy or solder.
  • the techniques illustrated in system 100 ensure that the precise alignment between substrate 102 and substrate 104 is maintained during the bonding process.
  • the system 100 ensures that substrate 102 and substrate 104 remain in direct contact without liquid intermediary in between during the bonding process.
  • the liquid intermediary can cause misalignment between substrate 102 and substrate 104.
  • the misalignment can create issues in optical coupling and electrical conductivity, among others, when the contact between substrate 102 and substrate 104 induces optical coupling and electrical conductivity. For example, if the position of the alignment is greater than a threshold, then the optical coupling and electrical conductivity may not meet factory or designer specifications.
  • substrates 102 and 104 are aligned and firmly pressed together without any adhesive applied in between. While holding the substrates together tightly, liquid epoxy or solder is deposited onto the substrate 104 and heated to cause flowing via surface wetting and capillary force. In particular, the liquid adhesive will flow to the joining section and fill in the gap between the two substrates and bonding them Atorney Docket No. 41703-0041W01//86229795PCT02 upon solidification. Throughout the bonding process, a portion of the joining surface remains in direct contact without liquid adhesive as intermediary to facilitate sliding.
  • the substrate 102 and substrate 104 are aligned and contacted together before the adhesive is applied, as shown in system 100. In some implementations, the alignment between the substrate 102 and the substrate 104 occurs before placing the substrate 102 in contact with substrate 104.
  • the substrate 104 also includes a primer 108 located on its top center portion.
  • the primer 108 illustrated by the patterned texture in system 100, facilitates the adhesive to flow in the desired direction of the primer 108.
  • the primer 108 is applied or deposited between the one or more pedestals 109 on the substrate 104.
  • the substrate 102 and the substrate 104 are aligned.
  • the precise alignment can be based on designer or factory specifications.
  • the substrate 102 can be aligned over top of the substrate 104.
  • the substrate 104 may include one or more pedestals 109 for facilitating the alignment and contact between the substrate 102 and the substrate 104.
  • the one or more pedestals 109 may be included and attached to a bottom portion of the substrate 102 to mate with a pedestal port 103 formed within a bottom portion of substrate 102.
  • the bottom portion of the substrate 102 may include the same number of pedestal ports as the number of pedestals 109. Any known configuration of pedestals or mating connectors that can be used to guide pieces into alignment with each other may be used.
  • a pedestal port 103 is used as a socket to receive and mate with pedestals 109 and may have a depth equivalent to the height of a pedestal 109.
  • the pedestal port 103 may have a depth that is less than the height of the pedestal 109, so only a portion of the pedestal 109 fits within the pedestal port 103 during the contact process.
  • the bottom portion of the substrate 102 may not include one or more pedestal ports 103, and consequently, the top of the one or more pedestals 109 come in contact with only the bottom portion of the substrate 102.
  • the bottom of the substrate 102 may include one or more pedestals in addition to the one or more pedestals included on the top portion of the substrate 104.
  • the gap formed between the substrates 102 and 104 is higher than if the Atorney Docket No. 41703-0041W01//86229795PCT02 botom of substrate 102 had pedestal ports 103.
  • the gap formed between the substrates 102 and 104 may be two times the height of the gap without pedestals on the botom of substrate 102.
  • the bottom portion of the substrate 102 does not include one or more pedestal ports 103 or the botom portion of the substrate 102 does include one or more pedestal ports 103 and the depth of those pedestal ports 103 is less than a height of a pedestal 109
  • a gap is created between the contacted substrates 102 and 104.
  • the gap between the substrates 102 and 104 is defined by the height of the pedestals 109 and a contact point between the top of the pedestals 109 and the botom of the substrate 102.
  • the gap formed has a smaller depth than if the bottom of the substrate 102 did not include the one or more pedestal ports 103.
  • the gap formed between the substrate 102 and the substrate 104 would include a distance equivalent to the height of the one or more pedestals 109.
  • the height of the one or more pedestals 109 can be set by designer and factor specifications, and they can be placed at various locations on the top of the substrate 104.
  • a primer 108 is applied to a top portion of the substrate 104.
  • the primer 108 is applied before the substrates 102 and 104 are aligned.
  • the primer 108 facilitates the movement of adhesive to flow in the direction of the gap.
  • the primer 108 can be an adhesive-amiable primer or under bump metallurgy if the adhesives in system 100 are solder.
  • the primer 108 can be a wet primer. In other examples, the primer 108 can be a wet primer that has dried.
  • the top portion of the substrate 104 receives deposits of adhesives 106-A and 106-B.
  • the adhesives 106-A and 106-B can be applied such that they do not come into contact with the substrate 102 during the contact process.
  • the adhesives 106 can be deposited to substrate 104 before contact is made between the substrate 102 and substrate 104.
  • the adhesives 106 can be deposited to substrate 104 after contact is made between the substrate 102 and substrate 104.
  • the adhesives 106 would be applied to the substrate 104 after the substrates 102 and 104 come in contact and when a gap exists between the contacted substrates 102 and 104.
  • the adhesives 106 can be deposited at various locations on the top surface of the substrate 104.
  • adhesive is pre-deposited solder in solid form.
  • deposition techniques can include (i) photolithography-defined paterns selectively Atorney Docket No. 41703-0041W01//86229795PCT02 populated solder pads introduces by evaporation or sputtering; (ii) solder balls planted via laser jetting; and (iii) solder preform picked-and-placed.
  • the solder can be melted by heating the entire assembly, by laser heating the solder, or powering up pre-deposited thin film resistive heater on either substrates 102 and 104.
  • solder offers electrical conductivity, good thermal dissipation, good long-term reliability, and ease of controlling its flowing path via wettability to pre-defmed metal tracks.
  • the laser and resistive heating methods offer the additional benefit of limited local heating to minimize thermal expansion of surrounding mechanical fixtures.
  • stage B substrate 102 and substrate 104 are contacted together at the one or more pedestals 109.
  • the radiation 110 can be in the form of heat, ultraviolet (UV) light, or gas jetting, to name a few examples. Any suitable radiation and radiation technique can be applied.
  • UV ultraviolet
  • the adhesives 106 begins to melt and wicks into the at least one gap formed by the contact position between the substrate 102 and the substrate 104.
  • the adhesives 106 are wicked into the at least one gap formed by capillary forces.
  • capillary action or forces is the result or ability of a liquid to flow in narrow spaces without the assistance of, or even in opposition to, external forces, such as gravity.
  • the alignment position at the contact points between the substrate A 102 and the substrate B 104 are maintained while the adhesive 106- A and 106-B is wicked into the at least one gap. Additionally, the primer 108 located on the top portion of the substrate B 104 improves the primer l08’s ability to attract the adhesives 106-A and 106-B to flow towards the at least one gap.
  • the adhesives 106 are wicked into the at least one gap between the two substrates 102 and 104.
  • the resultant substrate 112 includes the two substrates 102 and 104 in contact with one another and the adhesives 106 wicked in the gap between the two substrates 102 and 104.
  • additional radiation can be applied to the resultant substrate 112.
  • FIG. 2 is a block diagram that illustrates an example of a system 200 bonding together substrates including a trench between the substrates.
  • System 200 is similar to system 100.
  • system 200 includes a substrate 202, a substrate 204, adhesives 206-A and 206-B (collectively“adhesives 206”), and a primer 208.
  • system 200 includes an embedded trench 205 within a top portion of the substrate 204.
  • the embedded trench 205 within the center portion of the substrate 204 improves the ability of the adhesives 206 to wick into the region where the primer 208, illustrated by the patterned texture in system 200, exists.
  • the embedded trench 205 creates a gap between the substrate 202 and substrate 204.
  • the height of the embedded trench includes a distance of at least half the height of the substrate 204. In some examples, the height of the embedded trench includes a distance of the height of the substrate 204.
  • the substrate 202 is aligned over a top portion of the embedded trench 205 within the substrate 204.
  • the substrate 202 is aligned in a longitudinal manner over the embedded trench 205 of substrate
  • the substrate 202 is aligned in a parallel manner over the embedded trench 205 of the substrate 204.
  • the primer 208 can be applied within the embedded trench 205.
  • the primer 208 can be a wet primer.
  • the primer 208 can be a wet primer that has dried.
  • the adhesives 206 can be deposited to each end of the primer 208 within the embedded trench 205, such that the substrate 202 does not come into contact with the adhesives 206 during the process of placing substrate 202 in contact with substrate 204.
  • stage B the substrate 202 is placed in contact with substrate 204 over the embedded trench 205. As illustrated in system 200, the substrate 202 does not come into contact with the deposited adhesives 206. Radiation is applied to the deposited adhesives 206 at an angle. The angle can range from 0 degrees to 90 degrees relative to the top surface of substrate 204.
  • stage C the deposited adhesives 206 wick into the region of the primer 208 based on the applied radiation 210, the resulting capillary forces, and the region of the trench
  • the resultant substrate 212 shows the adhesives 206 underneath the substrate 202 due to its wicking from the radiation and the substrates 202 and 204 remaining in proper alignment and contact with one another.
  • FIG. 3 is a block diagram that illustrates an example of a system 300 bonding together substrates including a non-uniform surface between the substrates.
  • the system 300 is similar to systems 200 and 100. However, system 300 shows a substrate 302 and a substrate 304.
  • the surfaces of substrates 302 and 304 that contact one another may be non-uniform.
  • the non-uniform surfaces can include a rough surface, an irregular patterned surface, an abrasive surface, and an uneven surface, to name a few examples.
  • only the bottom surface of substrate 302 or only the top surface of substrate 304 has non-uniform characteristics. In some examples, both bottom surface of Atorney Docket No.
  • 41703-0041W01//86229795PCT02 substrate 302 and top surface of substrate 304 have non-uniform characteristics.
  • the adhesives 306 can wick into the primer 308, illustrated by the patterned texture in system 300, through the micro-channels of the non-uniform surfaces during stage B of the manufacturing of system 300.
  • the substrate 302 is aligned with substrate 304.
  • the adhesives 306 are deposited or applied to a top surface of the substrate 304.
  • the adhesives 306 are deposited in such a way that when substrate 302 contacts with substrate 304, the adhesives 306 do not come into contact with substrate 302.
  • stage B the substrate 302 comes in contact with substrate 304 in the alignment position. Pressure is applied to the substrate 302 and substrate 304 to hold the two substrates in place, e.g., in the proper alignment position. While pressure is applied, radiation 310 is applied to the adhesives 306.
  • the radiation 310 can be either heat or ultraviolet (UV) light.
  • UV ultraviolet
  • the radiation 310 can be applied at any angle relative to the top surface of substrate 304. The pressure applied creates a high friction surface at the contact point between substrate 302 and substrate 304, and thus, no adhesive or liquid can get into the contact point. As a result, the substrate 302 and substrate 304 will not move out of alignment during the adhesion process.
  • the radiated adhesives 306 are wicked into the region of the primer 308 due to capillary forces.
  • the radiated adhesives 306 are wicked into the region of the primer 308 through micro-channels provided by the non-uniform surface on the bottom of substrate 302, the non-uniform surface on the top of substrate 304, or a combination of both surfaces having non-uniform patterns.
  • the system 300 includes a primer 308 that is similar to primers 108 and 208.
  • the primer 304 facilitates the adhesives 306 to flow in the desired direction of the primer 308 during the radiation process.
  • FIG. 4 is a flow diagram that illustrates an example of a process 400 for bonding together substrates and wi eking adhesives between the substrates.
  • the process 400 includes stages similar to stages described with respect to systems 100, 200, and 300.
  • the process 400 includes stages A, B, and C.
  • substrate 402 is aligned with substrate 404.
  • the bottom surface of substrate 402 can include a non-uniform surface, such as a rough texture, a patterned interlocking feature, a solid or dry contact, an uneven surface, a high friction surface, or a combination of each.
  • the top surface of substrate 404 can similarly include a non-uniform surface, such as a rough texture, a patterned interlocking feature, a solid or dry contact, an uneven surface, a high friction surface, or a combination of each.
  • the bottom surface of substrate 402 and the top surface of substrate 404 can include one or more pedestals for connecting the two substrates.
  • the pedestals can be used to maintain proper alignment during the contact and wicking of the adhesives.
  • the pedestals may only be included on the top surface of substrate 404, only on the bottom surface of substrate 402, or on both top and bottom surfaces of substrates 404 and 402, respectively.
  • the bottom surface of substrate 402 may include one or more pedestal ports for accepting the pedestals included on the top of substrate 404.
  • the top surface of substrate 404 may include one or more pedestal ports for accepting the pedestals included on the bottom of substrate 402.
  • the adhesives 406-A and 406-B can wick into the gap without disturbing the alignment at the contact points between the two substrates 402 and 404. If one of the substrates includes one or more pedestal ports, the gap between the two substrates 402 and 404 is vertically reduced. In some examples, the pedestals may also be used to ensure that the bottom surface and the top surface of substrate 402 and substrate 404, respectively, do not touch one another.
  • a syringe can deposit adhesives to the top surface of substrate 404.
  • the adhesive can be applied either before the alignment initiates between substrate 402 and substrate 404 or after the alignment has occurred. If the adhesive is epoxy, the adhesive is applied after the alignment is achieved. Additionally, the epoxy can be applied either before or after the substrate 402 and substrate 404 make contact. Alternatively, if the adhesive is solder, the adhesive is introduced to the top portion of substrate 404 either by depositing before alignment or by paste dispensing or laser jetting after the substrates 402 and 404 make contact. The epoxy or solder paste can be dispensed with the syringe near the contact point.
  • the solder paste can include flux that facilitates wetting and flowing of solder, facilitating the ability to wick into narrow gaps surrounding the contact point.
  • the epoxy which has a lower viscosity than solder paste, has an easier ability to wick into the narrow gaps. Additionally, epoxy permits athermal solidification using UV light irradiation and thus, eliminating the risk of thermal expansion.
  • stage B the substrates 402 and 404 are pressed together with high friction surfaces in direct contact without any adhesive in between.
  • the adhesives on the top surface of the substrate 404 do not come into contact with the substrate 402.
  • the adhesive is wicked into the gaps between the substrate 402 and substrate 404.
  • the adhesive is wicked into the gaps while applying radiation, e.g., heat or UV light, to achieve bonding between substrates 402 and 404.
  • radiation e.g., heat or UV light
  • a vacuum can be applied to the center point between substrates 402 and 404 to cause the adhesive to wick into the gaps.
  • the temperature of the adhesive can be decreased to allow the bonding to solidify.
  • a primer can be placed on the top surface of the substrate 404 within the gap.
  • the primer can be a proper under bump metallization, e.g., UBM, which will facilitate the flow of molten solder towards the primer.
  • FIG. 5 is a flow diagram that illustrates an example of a process 500 for bonding together substrates and wi eking adhesive between the substrates.
  • a first substrate is aligned to contact a second substrate (502).
  • a primer is applied to a top portion of the second substrate to facilitate the flow of adhesive towards a gap formed when the first substrate contacts the second substrate.
  • a bottom portion of the first substrate and a top portion of second substrate may include one or more pedestals.
  • the bottom portion of the first substrate can include one or more pedestal ports for accepting the one or more pedestals from the top portion of the second substrate, and vice versa.
  • a height of the pedestals in contact can define a height of the at least one gap later formed at the contact position between the first substrate and the second substrate.
  • the adhesive can be, for example, epoxy or solder.
  • the adhesive can be applied either before the aligning and contacting steps or afterwards. If the adhesive is epoxy, the epoxy is applied after aligning and placing the first substrate in contact with the second substrate. If the adhesive is solder, the Atorney Docket No. 41703-0041W01//86229795PCT02 solder is applied before aligning and placing the first substrate in contact with the second substrate.
  • a first substrate is placed in contact with the second substrate (506).
  • the contact surfaces of the first substrate and the second substrate e.g., either through the one or more pedestals, the one or more pedestal ports, or the bottom and top surfaces of the first and second substrates, may include a non-uniformity.
  • the non-uniformity surfaces may include a rough surface, an uneven surface, an abrasive surface, and an irregularly patterned surface.
  • Radiation is applied to the adhesive (508).
  • the radiation causes the adhesive to wick into at least one gap formed in proximity to the contact position between the first substrate and the second substrate. Additionally, while the radiation is applied to the adhesive to cause the adhesive to wick, an alignment created during alignment and contact of the first substrate and the second substrate remains in the same position.

Landscapes

  • Engineering & Computer Science (AREA)
  • Computer Hardware Design (AREA)
  • Microelectronics & Electronic Packaging (AREA)
  • Power Engineering (AREA)
  • Mechanical Engineering (AREA)
  • Manufacturing & Machinery (AREA)
  • Physics & Mathematics (AREA)
  • Optics & Photonics (AREA)
  • Particle Formation And Scattering Control In Inkjet Printers (AREA)
  • Combinations Of Printed Boards (AREA)

Abstract

Methods, systems, and apparatus, including computer programs encoded on computer storage media, for precision chip bonding by adhesive wicking. In some implementations, an apparatus includes a first substrate, a second substrate, a primer, and an adhesive. The second substrate is aligned with the first substrate and contacting the first substrate with the second substrate at an at least one contact position. The primer is located on a top portion of the second substrate in a gap in proximity to the at least one contact position between the second substrate and the first substrate. An adhesive is wicked into the gap in proximity to the at least one contact position between the second substrate and the first substrate towards the primer through radiation.

Description

PRECISION CHIP BONDING BY ADHESIVE WICKING
BACKGROUND
[0001] Optical component assembly and packaging bonding usually requires precise alignment. The tolerance for precise alignment includes below one-micrometer using submicron precision, for example.
[0002] Typical adhesive bonding processes involve sandwiching the adhesive between two parts to be bonded and introducing energy to solidify the adhesive thus bonding the two parts. Before its solidification, however, the adhesive may act as a lubricant and facilitate relative sliding between the two parts to be bonded. The relative sliding introduces misalignment during the adhesive bonding process. Typically, optical component assembly and packaging primarily employs fixtures to provide mechanical constraints on the parts to be bonded. However, fixtures may undergo minute movements induced by thermal expansion, due to energy introduction, and the slippery liquid adhesive will exacerbate the movement that results in misalignment of parts after solidification of the adhesive.
SUMMARY
[0003] In some implementations, the techniques of this specification address the slippery adhesive issue by ensuring the two parts to be bonded remain stationary with respect to each other during the adhesive solidification process. In particular, at least a portion of both surfaces of the two parts to be bonded remains in direct contact without liquid intermediary, namely the adhesive prior to its solidification, throughout the bonding process. During the adhesive bonding process, the adhesive wicks into one or more gaps surrounding the contact portion between the two parts via a capillary force. By wicking the adhesive into the gaps this incurs an increased benefit of friction and ultimately, minimizes the sliding and improves the post bond alignment precision by reducing the amount of misalignment of parts during the solidification of the adhesive. After the adhesive wicks into the gaps and solidifies, the parts are bonded together.
[0004] In one general aspect, a method includes: aligning a first substrate to contact a second substrate; applying an adhesive to at least one top portion of the second substrate in proximity to a contact position between the first substrate and the second substrate; placing a first substrate in contact with a second substrate; and applying radiation to the adhesive, wherein applying the radiation to the adhesive causes the adhesive to wick into at least one gap formed in proximity to the contact position between the first substrate and the second substrate. Atorney Docket No. 41703-0041W01//86229795PCT02
[0005] Other embodiments of this and other aspects of the disclosure may include computer programs as well as corresponding systems, apparatus, and processors configured to perform the actions of the methods, encoded on computer storage devices. A system of one or more computers can be so configured by virtue of software, firmware, hardware, or a combination of them installed on the system that in operation cause the system to perform the actions. One or more computer programs have instructions that, when executed by data processing apparatus, cause the apparatus to perform the actions.
[0006] The foregoing and other embodiments can each optionally include one or more of the following features, alone or in combination. For example, one embodiment includes all the following features in combination.
[0007] In some implementations, the second substrate includes an embedded trench at a center portion of the second substrate, and wherein aligning the first substrate to contact the second substrate, the method further includes: aligning the first substrate to contact the second substrate over the center portion; applying the adhesive to the at least one top portion of the second substrate in the embedded trench without contacting the first substrate; placing the first substrate to contact with the second substrate over the center portion; and applying the radiation to the adhesive causes the adhesive to wick into the at least one gap formed at the center portion in the embedded trench on the second substrate while maintaining alignment between the first and second substrates.
[0008] In some implementations, the method includes applying a primer to the second substrate for facilitating the adhesive to flow towards the at least one gap.
[0009] In some implementations, applying the adhesive to the at least one top portion of the second substrate further includes: applying the adhesive to the at least one top portion of the second substrate in proximity to the contact position between the first substrate and the second substrate without coming into contact with the first substrate.
[0010] In some implementations, applying the radiation to the adhesive causes the adhesive to wick into the at least one gap further includes: applying the radiation to the adhesive, wherein applying the radiation to the adhesive causes the adhesive to wick into the at least one gap formed between the contact position while maintaining in an alignment position created during alignment of the first substrate to contact the second substrate.
[0011] In some implementations, the second substrate includes at least one pedestal, and wherein placing the first substrate in contact with the second substrate includes placing the first substrate in contact with the second substrate at the at least one pedestal, and wherein a height Attorney Docket No. 41703-0041W01//86229795PCT02 of the at least one pedestal at the contact position defines a height of the at least one gap formed at the contact position between the first substrate and the second substrate.
[0012] In some implementations, the first substrate has a high friction surface, wherein the second substrate has a high friction surface, and wherein placing the first substrate in contact with the second substrate includes applying the high friction surface of the first substrate to contact the high friction surface of the second substrate at the contact position, wherein the adhesive is not applied between the contact position.
[0013] In some implementations, the high friction surface includes a rough finish or a pattern or interlocking features.
[0014] In some implementations, the adhesive includes epoxy or solder.
[0015] In some implementations, when the adhesive is epoxy, the method further includes applying the adhesive to the at least one top portion of the second substrate after aligning and forming the first substrate to contact the second substrate.
[0016] In some implementations, when the adhesive is solder, the method further includes depositing the adhesive to the at least one top portion of the second substrate before aligning and forming the first substrate to contact the second substrate.
[0017] The details of one or more embodiments of the subject matter of this specification are set forth in the accompanying drawings and the description below. Other features, aspects, and advantages of the subject matter will become apparent from the description, the drawings, and the claims.
BRIEF DESCRIPTION OF THE DRAWINGS
[0018] FIG. 1 is a block diagram that illustrates an example of a system bonding together substrates using pedestals between the substrates.
[0019] FIG. 2 is a block diagram that illustrates an example of a system bonding together substrates including a trench between the substrates.
[0020] FIG. 3 is a block diagram that illustrates an example of a system bonding together substrates including a non-uniform surface between the substrates.
[0021] FIG. 4 is a flow diagram that illustrates an example of a process for bonding together substrates and wicking adhesives between the substrates.
[0022] FIG. 5 is a flow diagram that illustrates an example of a process for bonding together substrates and wicking adhesive between the substrates.
[0023] Like reference numbers and designations in the various drawings indicate like elements. Atorney Docket No. 41703-0041W01//86229795PCT02
DETAILED DESCRIPTION
[0024] Typical optical component assembly/packaging during an adhesive process requires precise alignment, e.g., often within a micrometer or less of error. However, the optical components can incur misalignment during the adhesive process because adhesive can act as a lubricant and facilitate relative sliding between the optical components. The relative sliding creates negative effects for the optical component assembly, such as a detrimental optical loss, a reduced electrical conductivity and an inoperable assembly package. By ensuring the adhesive is not applied between the optical components, the optical components can be safely aligned and positioned in contact with one another during the adhesive process.
[0025] FIG. 1 is a block diagram that illustrates an example of a system 100 bonding together substrates using pedestals between the substrates. The system 100 includes two substrates - substrate 102 and substrate 104 in three stages of manufacture illustrated as A, B and C. In particular, the system 100 illustrates the process of aligning tow substrates together, applying an adhesive to the second substrate, placing a first substrate in contact with the second substrate, and applying radiation to the adhesive causing the adhesive to wick into a gap formed next to the contact position between the first and second substrate. For example, the substrates 102 and 104 can be composed of glass, silicon, polymer, hybrid components, and other components. The system 100 also includes adhesive 106-A and 106-B deposited on a top portion of the substrate B 104. For example, the adhesive can be deposited as epoxy or solder.
[0026] The techniques illustrated in system 100 ensure that the precise alignment between substrate 102 and substrate 104 is maintained during the bonding process. In particular, the system 100 ensures that substrate 102 and substrate 104 remain in direct contact without liquid intermediary in between during the bonding process. The liquid intermediary can cause misalignment between substrate 102 and substrate 104. The misalignment can create issues in optical coupling and electrical conductivity, among others, when the contact between substrate 102 and substrate 104 induces optical coupling and electrical conductivity. For example, if the position of the alignment is greater than a threshold, then the optical coupling and electrical conductivity may not meet factory or designer specifications.
[0027] To prevent sliding during the bonding process, substrates 102 and 104 are aligned and firmly pressed together without any adhesive applied in between. While holding the substrates together tightly, liquid epoxy or solder is deposited onto the substrate 104 and heated to cause flowing via surface wetting and capillary force. In particular, the liquid adhesive will flow to the joining section and fill in the gap between the two substrates and bonding them Atorney Docket No. 41703-0041W01//86229795PCT02 upon solidification. Throughout the bonding process, a portion of the joining surface remains in direct contact without liquid adhesive as intermediary to facilitate sliding.
[0028] During typical bonding processes, an adhesive is sandwiched between substrate 102 and substrate 104. Then, radiation is applied to the adhesive between the sandwiched substrates. However, the adhesive may become lubricated and cause the contact points between substrate 102 and substrate 104 to slip during the radiation process. Thus, in order to prevent the slippage from occurring and in contrast to typical bonding processes, the substrate 102 and substrate 104 are aligned and contacted together before the adhesive is applied, as shown in system 100. In some implementations, the alignment between the substrate 102 and the substrate 104 occurs before placing the substrate 102 in contact with substrate 104.
[0029] The substrate 104 also includes a primer 108 located on its top center portion. The primer 108, illustrated by the patterned texture in system 100, facilitates the adhesive to flow in the desired direction of the primer 108. The primer 108 is applied or deposited between the one or more pedestals 109 on the substrate 104.
[0030] During stage A, the substrate 102 and the substrate 104 are aligned. The precise alignment can be based on designer or factory specifications. In particular, the substrate 102 can be aligned over top of the substrate 104. The substrate 104 may include one or more pedestals 109 for facilitating the alignment and contact between the substrate 102 and the substrate 104. In some examples, the one or more pedestals 109 may be included and attached to a bottom portion of the substrate 102 to mate with a pedestal port 103 formed within a bottom portion of substrate 102. For example, the bottom portion of the substrate 102 may include the same number of pedestal ports as the number of pedestals 109. Any known configuration of pedestals or mating connectors that can be used to guide pieces into alignment with each other may be used. For example, a combination of pedestals and mating sockets may be used. Here, a pedestal port 103 is used as a socket to receive and mate with pedestals 109 and may have a depth equivalent to the height of a pedestal 109. In some examples, the pedestal port 103 may have a depth that is less than the height of the pedestal 109, so only a portion of the pedestal 109 fits within the pedestal port 103 during the contact process. In some examples, the bottom portion of the substrate 102 may not include one or more pedestal ports 103, and consequently, the top of the one or more pedestals 109 come in contact with only the bottom portion of the substrate 102. In some examples, instead of having pedestal ports 103 at the bottom of the substrate 102, the bottom of the substrate 102 may include one or more pedestals in addition to the one or more pedestals included on the top portion of the substrate 104. By having pedestals on both substrates, the gap formed between the substrates 102 and 104 is higher than if the Atorney Docket No. 41703-0041W01//86229795PCT02 botom of substrate 102 had pedestal ports 103. For example, the gap formed between the substrates 102 and 104 may be two times the height of the gap without pedestals on the botom of substrate 102.
[0031] In the case that the bottom portion of the substrate 102 does not include one or more pedestal ports 103 or the botom portion of the substrate 102 does include one or more pedestal ports 103 and the depth of those pedestal ports 103 is less than a height of a pedestal 109, after substrates 102 and 104 have contacted, a gap is created between the contacted substrates 102 and 104. The gap between the substrates 102 and 104 is defined by the height of the pedestals 109 and a contact point between the top of the pedestals 109 and the botom of the substrate 102. If the botom of the substrate 102 includes the one or more pedestal ports 103 having a particular depth, then the gap formed has a smaller depth than if the bottom of the substrate 102 did not include the one or more pedestal ports 103. Alternatively, if the bottom of the substrate 102 does not include the one or more pedestal ports 103, then the gap formed between the substrate 102 and the substrate 104 would include a distance equivalent to the height of the one or more pedestals 109. The height of the one or more pedestals 109 can be set by designer and factor specifications, and they can be placed at various locations on the top of the substrate 104.
[0032] A primer 108 is applied to a top portion of the substrate 104. In some examples, the primer 108 is applied before the substrates 102 and 104 are aligned. The primer 108 facilitates the movement of adhesive to flow in the direction of the gap. For example, the primer 108 can be an adhesive-amiable primer or under bump metallurgy if the adhesives in system 100 are solder. In some examples, the primer 108 can be a wet primer. In other examples, the primer 108 can be a wet primer that has dried.
[0033] In some examples, the top portion of the substrate 104 receives deposits of adhesives 106-A and 106-B. The adhesives 106-A and 106-B (collectively“adhesives 106”) can be applied such that they do not come into contact with the substrate 102 during the contact process. In some examples, the adhesives 106 can be deposited to substrate 104 before contact is made between the substrate 102 and substrate 104. In some examples, the adhesives 106 can be deposited to substrate 104 after contact is made between the substrate 102 and substrate 104. The adhesives 106 would be applied to the substrate 104 after the substrates 102 and 104 come in contact and when a gap exists between the contacted substrates 102 and 104. The adhesives 106 can be deposited at various locations on the top surface of the substrate 104.
[0034] In some implementations, adhesive is pre-deposited solder in solid form. In particular, deposition techniques can include (i) photolithography-defined paterns selectively Atorney Docket No. 41703-0041W01//86229795PCT02 populated solder pads introduces by evaporation or sputtering; (ii) solder balls planted via laser jetting; and (iii) solder preform picked-and-placed. The solder can be melted by heating the entire assembly, by laser heating the solder, or powering up pre-deposited thin film resistive heater on either substrates 102 and 104. By using solder for adhesive, some benefits exist. For example, solder offers electrical conductivity, good thermal dissipation, good long-term reliability, and ease of controlling its flowing path via wettability to pre-defmed metal tracks. The laser and resistive heating methods offer the additional benefit of limited local heating to minimize thermal expansion of surrounding mechanical fixtures.
[0035] During stage B, substrate 102 and substrate 104 are contacted together at the one or more pedestals 109.
[0036] Once the substrate 102 and substrate 104 are in contact radiation 110 is applied to the adhesives 106. The radiation 110 can be in the form of heat, ultraviolet (UV) light, or gas jetting, to name a few examples. Any suitable radiation and radiation technique can be applied. During the application of radiation 110 to the adhesives 106, the adhesives 106 begins to melt and wicks into the at least one gap formed by the contact position between the substrate 102 and the substrate 104. The adhesives 106 are wicked into the at least one gap formed by capillary forces. In particular, capillary action or forces is the result or ability of a liquid to flow in narrow spaces without the assistance of, or even in opposition to, external forces, such as gravity. The alignment position at the contact points between the substrate A 102 and the substrate B 104 are maintained while the adhesive 106- A and 106-B is wicked into the at least one gap. Additionally, the primer 108 located on the top portion of the substrate B 104 improves the primer l08’s ability to attract the adhesives 106-A and 106-B to flow towards the at least one gap.
[0037] During stage C, the adhesives 106 are wicked into the at least one gap between the two substrates 102 and 104. The resultant substrate 112 includes the two substrates 102 and 104 in contact with one another and the adhesives 106 wicked in the gap between the two substrates 102 and 104. To solidify the adhesives 110 between the substrates 102 and 104 in the resultant substrate 112, additional radiation can be applied to the resultant substrate 112.
[0038] FIG. 2 is a block diagram that illustrates an example of a system 200 bonding together substrates including a trench between the substrates. System 200 is similar to system 100. For example, system 200 includes a substrate 202, a substrate 204, adhesives 206-A and 206-B (collectively“adhesives 206”), and a primer 208. However, system 200 includes an embedded trench 205 within a top portion of the substrate 204. Atorney Docket No. 41703-0041W01//86229795PCT02
[0039] The embedded trench 205 within the center portion of the substrate 204 improves the ability of the adhesives 206 to wick into the region where the primer 208, illustrated by the patterned texture in system 200, exists. In particular, the embedded trench 205 creates a gap between the substrate 202 and substrate 204. In some examples, the height of the embedded trench includes a distance of at least half the height of the substrate 204. In some examples, the height of the embedded trench includes a distance of the height of the substrate 204.
[0040] Thus, as shown in system 200, during stage (A), the substrate 202 is aligned over a top portion of the embedded trench 205 within the substrate 204. In some examples, the substrate 202 is aligned in a longitudinal manner over the embedded trench 205 of substrate
204. In some examples, the substrate 202 is aligned in a parallel manner over the embedded trench 205 of the substrate 204.
[0041] The primer 208 can be applied within the embedded trench 205. In some examples, the primer 208 can be a wet primer. In other examples, the primer 208 can be a wet primer that has dried. The adhesives 206 can be deposited to each end of the primer 208 within the embedded trench 205, such that the substrate 202 does not come into contact with the adhesives 206 during the process of placing substrate 202 in contact with substrate 204.
[0042] During stage B, the substrate 202 is placed in contact with substrate 204 over the embedded trench 205. As illustrated in system 200, the substrate 202 does not come into contact with the deposited adhesives 206. Radiation is applied to the deposited adhesives 206 at an angle. The angle can range from 0 degrees to 90 degrees relative to the top surface of substrate 204.
[0043] During stage C, the deposited adhesives 206 wick into the region of the primer 208 based on the applied radiation 210, the resulting capillary forces, and the region of the trench
205. The resultant substrate 212 shows the adhesives 206 underneath the substrate 202 due to its wicking from the radiation and the substrates 202 and 204 remaining in proper alignment and contact with one another.
[0044] FIG. 3 is a block diagram that illustrates an example of a system 300 bonding together substrates including a non-uniform surface between the substrates. The system 300 is similar to systems 200 and 100. However, system 300 shows a substrate 302 and a substrate 304. In some implementations, the surfaces of substrates 302 and 304 that contact one another may be non-uniform. For example, the non-uniform surfaces can include a rough surface, an irregular patterned surface, an abrasive surface, and an uneven surface, to name a few examples. In some examples, only the bottom surface of substrate 302 or only the top surface of substrate 304 has non-uniform characteristics. In some examples, both bottom surface of Atorney Docket No. 41703-0041W01//86229795PCT02 substrate 302 and top surface of substrate 304 have non-uniform characteristics. By having a surface or surfaces with non-uniform characteristics, the adhesives 306 can wick into the primer 308, illustrated by the patterned texture in system 300, through the micro-channels of the non-uniform surfaces during stage B of the manufacturing of system 300.
[0045] In particular, during stage A, the substrate 302 is aligned with substrate 304. The adhesives 306 are deposited or applied to a top surface of the substrate 304. However, the adhesives 306 are deposited in such a way that when substrate 302 contacts with substrate 304, the adhesives 306 do not come into contact with substrate 302.
[0046] During stage B, the substrate 302 comes in contact with substrate 304 in the alignment position. Pressure is applied to the substrate 302 and substrate 304 to hold the two substrates in place, e.g., in the proper alignment position. While pressure is applied, radiation 310 is applied to the adhesives 306. The radiation 310 can be either heat or ultraviolet (UV) light. The radiation 310 can be applied at any angle relative to the top surface of substrate 304. The pressure applied creates a high friction surface at the contact point between substrate 302 and substrate 304, and thus, no adhesive or liquid can get into the contact point. As a result, the substrate 302 and substrate 304 will not move out of alignment during the adhesion process.
[0047] During stage C, the radiated adhesives 306 are wicked into the region of the primer 308 due to capillary forces. In particular, the radiated adhesives 306 are wicked into the region of the primer 308 through micro-channels provided by the non-uniform surface on the bottom of substrate 302, the non-uniform surface on the top of substrate 304, or a combination of both surfaces having non-uniform patterns. Additionally, the system 300 includes a primer 308 that is similar to primers 108 and 208. The primer 304 facilitates the adhesives 306 to flow in the desired direction of the primer 308 during the radiation process.
[0048] FIG. 4 is a flow diagram that illustrates an example of a process 400 for bonding together substrates and wi eking adhesives between the substrates. The process 400 includes stages similar to stages described with respect to systems 100, 200, and 300. In particular, the process 400 includes stages A, B, and C.
[0049] During stage A, substrate 402 is aligned with substrate 404. The bottom surface of substrate 402 can include a non-uniform surface, such as a rough texture, a patterned interlocking feature, a solid or dry contact, an uneven surface, a high friction surface, or a combination of each. Additionally, the top surface of substrate 404 can similarly include a non-uniform surface, such as a rough texture, a patterned interlocking feature, a solid or dry contact, an uneven surface, a high friction surface, or a combination of each. These non- Atorney Docket No. 41703-0041W01//86229795PCT02 uniform surfaces increase the friction at the contact point between substrate 402 and substrate 404 and consequently, minimize sliding at the contact point during the adhesive process.
[0050] The bottom surface of substrate 402 and the top surface of substrate 404 can include one or more pedestals for connecting the two substrates. The pedestals can be used to maintain proper alignment during the contact and wicking of the adhesives. The pedestals may only be included on the top surface of substrate 404, only on the bottom surface of substrate 402, or on both top and bottom surfaces of substrates 404 and 402, respectively. In some examples, the bottom surface of substrate 402 may include one or more pedestal ports for accepting the pedestals included on the top of substrate 404. In some examples, the top surface of substrate 404 may include one or more pedestal ports for accepting the pedestals included on the bottom of substrate 402. By maintaining a gap between the two substrates 402 and 404, created as a result of the pedestals contacting, the adhesives 406-A and 406-B (collectively“adhesives 406”) can wick into the gap without disturbing the alignment at the contact points between the two substrates 402 and 404. If one of the substrates includes one or more pedestal ports, the gap between the two substrates 402 and 404 is vertically reduced. In some examples, the pedestals may also be used to ensure that the bottom surface and the top surface of substrate 402 and substrate 404, respectively, do not touch one another.
[0051] In some implementations, a syringe can deposit adhesives to the top surface of substrate 404. The adhesive can be applied either before the alignment initiates between substrate 402 and substrate 404 or after the alignment has occurred. If the adhesive is epoxy, the adhesive is applied after the alignment is achieved. Additionally, the epoxy can be applied either before or after the substrate 402 and substrate 404 make contact. Alternatively, if the adhesive is solder, the adhesive is introduced to the top portion of substrate 404 either by depositing before alignment or by paste dispensing or laser jetting after the substrates 402 and 404 make contact. The epoxy or solder paste can be dispensed with the syringe near the contact point. The solder paste can include flux that facilitates wetting and flowing of solder, facilitating the ability to wick into narrow gaps surrounding the contact point. The epoxy, which has a lower viscosity than solder paste, has an easier ability to wick into the narrow gaps. Additionally, epoxy permits athermal solidification using UV light irradiation and thus, eliminating the risk of thermal expansion.
[0052] During stage B, the substrates 402 and 404 are pressed together with high friction surfaces in direct contact without any adhesive in between. In some examples, the adhesives on the top surface of the substrate 404 do not come into contact with the substrate 402. Atorney Docket No. 41703-0041W01//86229795PCT02
[0053] During stage C, the adhesive is wicked into the gaps between the substrate 402 and substrate 404. The adhesive is wicked into the gaps while applying radiation, e.g., heat or UV light, to achieve bonding between substrates 402 and 404. In some implementations, a vacuum can be applied to the center point between substrates 402 and 404 to cause the adhesive to wick into the gaps. Once the adhesive wicks into the gap between substrates 402 and 404, the temperature of the adhesive can be decreased to allow the bonding to solidify.
[0054] In the case that the adhesive is solder, a primer can be placed on the top surface of the substrate 404 within the gap. The primer can be a proper under bump metallization, e.g., UBM, which will facilitate the flow of molten solder towards the primer.
[0055] By performing the solidification in the manner discussed relating to systems 100, 200, 300, and process 400, contact is always maintained between the bonding substrates at certain areas that are free of liquid adhesive. The adhesive wicks into the at least one gaps between bonding parts. Additionally, the adhesive solidifies via localized heating by laser, resistor, or athermal means such as UV irradiation in order to minimize thermal expansion of surrounding mechanical fixtures.
[0056] FIG. 5 is a flow diagram that illustrates an example of a process 500 for bonding together substrates and wi eking adhesive between the substrates.
[0057] A first substrate is aligned to contact a second substrate (502). A primer is applied to a top portion of the second substrate to facilitate the flow of adhesive towards a gap formed when the first substrate contacts the second substrate. A bottom portion of the first substrate and a top portion of second substrate may include one or more pedestals. In some examples, the bottom portion of the first substrate can include one or more pedestal ports for accepting the one or more pedestals from the top portion of the second substrate, and vice versa. In some examples, a height of the pedestals in contact can define a height of the at least one gap later formed at the contact position between the first substrate and the second substrate.
[0058] Apply an adhesive to at least one top portion of the second substrate in proximity to a contact position between the first substrate and the second substrate (504). The at least one top portion of the second substrate faces a bottom portion of the first substrate. Additionally, the applied adhesive does not come into contact with the first substrate when the first substrate and the second substrate are placed into contact. The adhesive can be, for example, epoxy or solder. The adhesive can be applied either before the aligning and contacting steps or afterwards. If the adhesive is epoxy, the epoxy is applied after aligning and placing the first substrate in contact with the second substrate. If the adhesive is solder, the Atorney Docket No. 41703-0041W01//86229795PCT02 solder is applied before aligning and placing the first substrate in contact with the second substrate.
[0059] A first substrate is placed in contact with the second substrate (506). The contact surfaces of the first substrate and the second substrate, e.g., either through the one or more pedestals, the one or more pedestal ports, or the bottom and top surfaces of the first and second substrates, may include a non-uniformity. For example, the non-uniformity surfaces may include a rough surface, an uneven surface, an abrasive surface, and an irregularly patterned surface.
[0060] Radiation is applied to the adhesive (508). When applying radiation to the adhesive, the radiation causes the adhesive to wick into at least one gap formed in proximity to the contact position between the first substrate and the second substrate. Additionally, while the radiation is applied to the adhesive to cause the adhesive to wick, an alignment created during alignment and contact of the first substrate and the second substrate remains in the same position.
[0061] Particular embodiments of the subject matter have been described. Other embodiments are within the scope of the following claims. For example, the actions recited in the claims can be performed in a different order and still achieve desirable results. Alternatively, alternative or combinations of adhesives, radiation, and other components or techniques may be applied, where appropriate and understood by one skilled in the art. As one example, the processes depicted in the accompanying figures do not necessarily require the particular order shown, or sequential order, to achieve desirable results.

Claims

Attorney Docket No. 41703-0041W01//86229795PCT02 CLAIMS What is claimed is:
1. A method comprising:
aligning a first substrate to contact a second substrate;
applying an adhesive to at least one top portion of the second substrate in proximity to a contact position between the first substrate and the second substrate;
placing a first substrate in contact with a second substrate; and
applying radiation to the adhesive, wherein applying the radiation to the adhesive causes the adhesive to wick into at least one gap formed in proximity to the contact position between the first substrate and the second substrate.
2. The method of claim 1, wherein the second substrate comprises an embedded trench at a center portion of the second substrate, and wherein aligning the first substrate to contact the second substrate, the method further comprising:
aligning the first substrate to contact the second substrate over the center portion; applying the adhesive to the at least one top portion of the second substrate in the embedded trench without contacting the first substrate;
placing the first substrate to contact with the second substrate over the center portion; and
applying the radiation to the adhesive causes the adhesive to wick into the at least one gap formed at the center portion in the embedded trench on the second substrate while maintaining alignment between the first and second substrates.
3. The method of claim 1, further comprising the step of applying a primer to the second substrate for facilitating the adhesive to flow towards the at least one gap.
4. The method of claim 1, wherein applying the adhesive to the at least one top portion of the second substrate further comprises:
applying the adhesive to the at least one top portion of the second substrate in proximity to the contact position between the first substrate and the second substrate without coming into contact with the first substrate. Attorney Docket No. 41703-0041W01//86229795PCT02
5. The method of claim 1, wherein applying the radiation to the adhesive causes the adhesive to wick into the at least one gap further comprises:
applying the radiation to the adhesive, wherein applying the radiation to the adhesive causes the adhesive to wick into the at least one gap formed between the contact position while maintaining in an alignment position created during alignment of the first substrate to contact the second substrate.
6. The method of claim 1, wherein the second substrate comprises at least one pedestal, and wherein placing the first substrate in contact with the second substrate comprises placing the first substrate in contact with the second substrate at the at least one pedestal, and wherein a height of the at least one pedestal at the contact position defines a height of the at least one gap formed at the contact position between the first substrate and the second substrate.
7. The method of claim 1, wherein the first substrate has a high friction surface, wherein the second substrate has a high friction surface, and wherein placing the first substrate in contact with the second substrate comprises applying the high friction surface of the first substrate to contact the high friction surface of the second substrate at the contact position, wherein the adhesive is not applied between the contact position.
8. The method of claim 7, wherein the high friction surface comprises a rough finish or a pattern of interlocking features.
9. The method of claim 1, wherein the adhesive comprises epoxy or solder.
10. The method of claim 9, wherein, when the adhesive is epoxy, the method further comprises applying the adhesive to the at least one top portion of the second substrate after aligning and forming the first substrate to contact the second substrate.
11. The method of claim 9, wherein, when the adhesive is solder, the method further comprises depositing the adhesive to the at least one top portion of the second substrate before aligning and forming the first substrate to contact the second substrate.
12. An apparatus comprising:
a first substrate; Atorney Docket No. 41703-0041W01//86229795PCT02 a second substrate aligned with the first substrate and contacting the first substrate with the second substrate at an at least one contact position;
a primer located on a top portion of the second substrate in a gap in proximity to the at least one contact position between the second substrate and the first substrate; and
an adhesive wicked into the gap in proximity to the at least one contact position between the second substrate and the first substrate towards the primer through radiation.
13. The apparatus of claim 13, wherein the second substrate comprises an embedded trench at a center portion of the second substrate and wherein the first substrate is aligned to contact the second substrate over the center portion, the apparatus further comprises:
the adhesive is applied to the top portion of the second substrate in the embedded trench without contacting the first substrate;
the first substrate is placed in contact with the second substrate over the center portion; and
the adhesive wicked into the gap formed at the center portion in the embedded trench on the second substrate while maintaining alignment between the first and second substrates.
14. The apparatus of claim 14, wherein the primer facilitates the adhesive to flow towards the gap formed at the center portion in the embedded trench.
15. The apparatus of claim 13, wherein the adhesive is applied to the top portion of the second substrate in proximity to the at least one contact position between the second substrate and the first substrate without coming into contact with the first substrate.
16. The apparatus of claim 13, wherein the second substrate comprises at least one pedestal, and wherein placing the first substrate in contact with the second substrate comprises placing the first substrate in contact with the second substrate at the at least one pedestal, and wherein a height of the at least one pedestal at the contact position defines a height of the gap formed at the contact position between the first substrate and the second substrate.
17. The apparatus of claim 13, wherein the first substrate has a high friction surface, wherein the second substrate has a high friction surface, and wherein placing the first substrate in contact with the second substrate comprises applying the high friction surface of the first Atorney Docket No. 41703-0041W01//86229795PCT02 substrate to contact the high friction surface of the second substrate at the contact position, wherein the adhesive is not applied between the contact position.
18. The apparatus of claim 18, wherein the high friction surface comprises a rough finish or a pattern of interlocking features.
19. The apparatus of claim 13, wherein the second substrate comprises at least one pedestal, and wherein the first substrate comprises at least one pedestal port for accepting the at least one pedestal, and wherein placing the first substrate in contact with the second substrate comprises placing the first substrate in contact with the second substrate by inserting the at least one pedestal into the at least one pedestal port.
PCT/US2019/057575 2019-10-23 2019-10-23 Precision chip bonding by adhesive wicking WO2020082092A1 (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
PCT/US2019/057575 WO2020082092A1 (en) 2019-10-23 2019-10-23 Precision chip bonding by adhesive wicking

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
PCT/US2019/057575 WO2020082092A1 (en) 2019-10-23 2019-10-23 Precision chip bonding by adhesive wicking

Publications (1)

Publication Number Publication Date
WO2020082092A1 true WO2020082092A1 (en) 2020-04-23

Family

ID=70284829

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/US2019/057575 WO2020082092A1 (en) 2019-10-23 2019-10-23 Precision chip bonding by adhesive wicking

Country Status (1)

Country Link
WO (1) WO2020082092A1 (en)

Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US20010048162A1 (en) * 2000-06-05 2001-12-06 Mitsubishi Denki Kabushiki Kaisha Semiconductor device having a structure of a multilayer interconnection unit and manufacturing method thereof
US20120089180A1 (en) * 2010-05-06 2012-04-12 Duke University Adhesive bonding composition and method of use
US20120180950A1 (en) * 2009-10-16 2012-07-19 Henkel Corporation Primer compositions to toughen adhesive bonds
US20140295150A1 (en) * 2013-03-28 2014-10-02 Nokia Corporation Method and apparatus for joining together multiple functional layers of a flexible display
US20150282329A1 (en) * 2014-03-31 2015-10-01 Apple Inc. Methods for Assembling Electronic Devices With Adhesive

Patent Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US20010048162A1 (en) * 2000-06-05 2001-12-06 Mitsubishi Denki Kabushiki Kaisha Semiconductor device having a structure of a multilayer interconnection unit and manufacturing method thereof
US20120180950A1 (en) * 2009-10-16 2012-07-19 Henkel Corporation Primer compositions to toughen adhesive bonds
US20120089180A1 (en) * 2010-05-06 2012-04-12 Duke University Adhesive bonding composition and method of use
US20140295150A1 (en) * 2013-03-28 2014-10-02 Nokia Corporation Method and apparatus for joining together multiple functional layers of a flexible display
US20150282329A1 (en) * 2014-03-31 2015-10-01 Apple Inc. Methods for Assembling Electronic Devices With Adhesive

Similar Documents

Publication Publication Date Title
TWI409887B (en) Rotational fill techniques for injection molding of solder
US5950908A (en) Solder supplying method, solder supplying apparatus and soldering method
JPH0272642A (en) Structure and method for connecting substrates
JP3028791B2 (en) How to mount chip components
US10175448B2 (en) Slotted configuration for optimized placement of micro-components using adhesive bonding
US9627347B2 (en) Method of manufacturing semiconductor device and semiconductor device manufacturing apparatus
EP3401052A1 (en) Room temperature glass-to-glass, glass-to-plastic and glass-to-ceramic/semiconductor bonding
CN101414617B (en) Solid-state image pickup device
EP0860023A1 (en) A flip-chip assembly
US20050196979A1 (en) Adapter apparatus with conductive elements mounted using curable material and methods regarding same
US20140285989A1 (en) Method of mounting semiconductor element, and semiconductor device
US9721812B2 (en) Optical device with precoated underfill
KR20030072001A (en) Structure of flip chip bonding and method for bonding
JP2020043188A (en) Manufacturing method for packaging substrate and packaging substrate
US8399296B2 (en) Airgap micro-spring interconnect with bonded underfill seal
US20140348463A1 (en) Optical device and method for manufacuturing the optical device
WO2020082092A1 (en) Precision chip bonding by adhesive wicking
US10816737B2 (en) Reflow compatible optical packaging
EP1345059A1 (en) Integrated micro-optical elements
US6375365B1 (en) Apparatus and packaging method to assemble optical modules to a common substrate with adjustable plugs
JPH05114800A (en) Electronic component mounting method and device
JP2005101242A (en) Method for forming solder bump
US20030077050A1 (en) Method for passive alignment of supports, particularly plates bearing optical components
KR102311945B1 (en) Method for bonding substrates while distributing a connecting material by bringing the substrate together
Boudreau et al. Fluxless die bonding for optoelectronics

Legal Events

Date Code Title Description
121 Ep: the epo has been informed by wipo that ep was designated in this application

Ref document number: 19872363

Country of ref document: EP

Kind code of ref document: A1

NENP Non-entry into the national phase

Ref country code: DE

122 Ep: pct application non-entry in european phase

Ref document number: 19872363

Country of ref document: EP

Kind code of ref document: A1