Structure and method for temporarily holding integrated circuit chips in accurate alignment

• US 20050158009A1
• Filed: 11/15/2004
• Published: 07/21/2005
• Est. Priority Date: 02/10/2000
• Status: Active Grant

• Current Assignee: EPIC Technologies Incorporated
• Original Assignee: EPIC Technologies Incorporated
• Inventors: Starenas, Paul V., Eichelberger, Charles W.
• Granted Patent: US 7,112,467 B2
• Time in Patent Office: Days
• US Class Current: 385/147
• CPC Class Codes: H01L 21/56 Encapsulations, e.g. encapsulation layers, coatings
• CPC Class Codes: H01L 2224/023 Redistribution layers [RDL] for bonding areas
• CPC Class Codes: H01L 2224/0401 Bonding areas specifically adapted for bump connectors, e.g. under bump metallisation [UBM]
• CPC Class Codes: H01L 2224/04105 Bonding areas formed on an encapsulation of the semiconductor or solid-state body, e.g. bonding areas on chip-scale packages
• CPC Class Codes: H01L 2224/05147 Copper [Cu] as principal constituent
• CPC Class Codes: H01L 2224/05155 Nickel [Ni] as principal constituent
• CPC Class Codes: H01L 2224/05644 Gold [Au] as principal constituent
• CPC Class Codes: H01L 2224/05647 Copper [Cu] as principal constituent
• CPC Class Codes: H01L 2224/11 Manufacturing methods
• CPC Class Codes: H01L 2224/1147 using a lift-off mask
• CPC Class Codes: H01L 2224/12105 Bump connectors formed on an encapsulation of the semiconductor or solid-state body, e.g. bumps on chip-scale packages
• CPC Class Codes: H01L 2224/13022 the bump connector being at least partially embedded in the surface
• CPC Class Codes: H01L 2224/13023 the whole bump connector protruding from the surface
• CPC Class Codes: H01L 2224/13099 Material
• CPC Class Codes: H01L 2224/16225 the item being non-metallic, e.g. insulating substrate with or without metallisation
• CPC Class Codes: H01L 2224/16235 the bump connector connecting to a via metallisation of the item
• CPC Class Codes: H01L 2224/20 Structure, shape, material or disposition of high density interconnect preforms
• CPC Class Codes: H01L 2224/211 Disposition
• CPC Class Codes: H01L 2224/24137 the bodies being arranged next to each other, e.g. on a common substrate
• CPC Class Codes: H01L 2224/32225 the item being non-metallic, e.g. insulating substrate with or without metallisation
• CPC Class Codes: H01L 2224/73267 : Layer and HDI connectors
• CPC Class Codes: H01L 2224/82 : by forming build-up interconnects at chip-level, e.g. for high density interconnects [HDI]
• CPC Class Codes: H01L 2224/83 : using a layer connector
• CPC Class Codes: H01L 2224/94 : at wafer-level, i.e. with connecting carried out on a wafer comprising a plurality of undiced individual devices
• CPC Class Codes: H01L 2224/97 : the devices being connected to a common substrate, e.g. interposer, said common substrate being separable into individual assemblies after connecting
• CPC Class Codes: H01L 23/3114 : the device being a chip scale package, e.g. CSP
• CPC Class Codes: H01L 23/49811 : Additional leads joined to the metallisation on the insulating substrate, e.g. pins, bumps, wires, flat leads H01L23/49827 takes precedence
• CPC Class Codes: H01L 23/5389 : the chips being integrally enclosed by the interconnect and support structures
• CPC Class Codes: H01L 24/11 : Manufacturing methods for bumps on insulating substrates H01L21/4853
• CPC Class Codes: H01L 24/13 : of an individual bump connector
• CPC Class Codes: H01L 24/19 : Manufacturing methods of high density interconnect preforms
• CPC Class Codes: H01L 24/97 : the devices being connected to a common substrate, e.g. interposer, said common substrate being separable into individual assemblies after connecting
• CPC Class Codes: H01L 2924/00 : Indexing scheme for arrangements or methods for connecting or disconnecting semiconductor or solid-state bodies as covered by H01L24/00
• CPC Class Codes: H01L 2924/0001 : Technical content checked by a classifier
• CPC Class Codes: H01L 2924/00014 : the subject-matter covered by the group, the symbol of which is combined with the symbol of this group, being disclosed without further technical details
• CPC Class Codes: H01L 2924/01005 : Boron [B]
• CPC Class Codes: H01L 2924/01006 : Carbon [C]
• CPC Class Codes: H01L 2924/01013 : Aluminum [Al]
• CPC Class Codes: H01L 2924/01022 : Titanium [Ti]
• CPC Class Codes: H01L 2924/01023 : Vanadium [V]
• CPC Class Codes: H01L 2924/01027 : Cobalt [Co]
• CPC Class Codes: H01L 2924/01029 : Copper [Cu]
• CPC Class Codes: H01L 2924/01033 : Arsenic [As]
• CPC Class Codes: H01L 2924/01039 : Yttrium [Y]
• CPC Class Codes: H01L 2924/01074 : Tungsten [W]
• CPC Class Codes: H01L 2924/01078 : Platinum [Pt]
• CPC Class Codes: H01L 2924/01079 : Gold [Au]
• CPC Class Codes: H01L 2924/014 : Solder alloys
• CPC Class Codes: H01L 2924/14 : Integrated circuits
• CPC Class Codes: H01L 2924/15311 : being a ball array, e.g. BGA
• CPC Class Codes: H01L 2924/30107 : Inductance
• CPC Class Codes: H01L 2924/351 : Thermal stress
• CPC Class Codes: H05K 3/4007 : Surface contacts, e.g. bumps H05K3/4092 takes precedence; deposition of finish layers on pads H05K3/24; forming solder bumps H05K3/3457

Abstract

Structure and method for temporarily holding at least one integrated circuit chip during packaging thereof are presented. A support plate has a release film secured to a main surface thereof. The support plate and release film allow UV light to pass therethrough. A UV curable chip adhesive is disposed over the release film for holding the at least one integrated circuit chip. After placement of the at least one integrated circuit chip in the WV curable chip adhesive, the WV curable chip adhesive is cured by WV light shone through the support plate and release film. As one example, the release film includes a WV release adhesive and the WV curable chip adhesive and UV release adhesive have a differential response to UV light which allows curing of the WV curable chip attach without release of the UV release adhesive.

Claims

1. A structure for temporarily holding at least one integrated circuit chip during packaging thereof, said structure comprising:

a support plate with a release film secured to a main surface thereof, said support plate and release film allowing UV light to pass therethrough; and

a UV curable chip adhesive disposed over said release film for holding said at least one integrated circuit chip during packaging thereof, wherein after placement of said at least one integrated circuit chip in said UV curable chip adhesive, said UV curable chip adhesive can be cured by UV light shone through said support plate and release film.

2. The structure of claim 1, wherein said release film comprises a UV release adhesive.

3. The structure of claim 2, wherein said UV curable chip adhesive and said UV release adhesive have a differential response to UV light.

4. The structure of claim 3, wherein said differential response comprises at least one of responses to UV light of different wavelength or responses to UV light of different energy.

5. The structure of claim 4, wherein said differential response comprises said responses to UV light of different energy, and wherein said UV curable chip adhesive cures with UV light at a lower energy level than an energy level at which said UV release adhesive releases.

6. The structure of claim 4, wherein said support plate comprises a glass plate and said release film comprises a polyester film with said UV release adhesive disposed thereon.

7. The structure of claim 1, wherein said at least one integrated circuit chip comprises a plurality of integrated circuit chips, and wherein said structure further comprises a structural material surrounding and physically contacting at least one side surface of each chip of said plurality of chips and mechanically interconnecting in spaced, planar relation said plurality of chips.

8. A method for temporarily holding at least one integrated circuit chip during packaging thereof, said method comprising:

(i) providing a support plate with a release film secured to a main surface thereof, said support plate and release film allowing UV light to pass therethrough;

(ii) providing a UV curable chip adhesive disposed over said release film;

(iii) placing said at least one integrated circuit chip in said UV curable chip adhesive; and

(iv) shining UV light through said support plate and release film to cure said UV curable chip adhesive, thereby holding said at least one integrated circuit chip where placed.

9. The method of claim 8, wherein said at least one integrated circuit chip comprises a plurality of integrated circuit chips, and wherein said placing (iii) comprises placing said plurality of integrated circuit chips face down in said UV curable chip adhesive.

10. The method of claim 9, further comprising applying a structural material surrounding and physically contacting at least one side surface of each chip of said plurality of chips to mechanically interconnect in spaced, planar relationship said plurality of chips.

11. The method of claim 10, further comprising removing said support plate, release film and UV curable chip adhesive after said structural filler material has been applied to mechanically interconnect in spaced, planar relation said plurality of chips.

12. The method of claim 11, wherein said release film comprises a release adhesive, and wherein said removing comprises removing said support plate along said release adhesive, and thereafter removing said release film and any remaining UV curable chip attach adhesive.

13. The method of claim 12, wherein said release adhesive comprises a UV release adhesive, and wherein said removing comprises shining UV light through said support plate to activate said UV release adhesive to release said support plate.

14. The method of claim 13, wherein said removing of said remaining UV curable chip attach adhesive comprises using acetone and plasma cleaning to remove remaining UV curable chip attach adhesive.

15. The method of claim 8, wherein said release film comprises a UV release adhesive, and wherein said UV curable chip adhesive and said UV release adhesive have a differential response to UV light.

16. The method of claim 15, wherein said differential response comprises at least one of responses to UV light of different wavelength or responses to UV light of different energy, and wherein said shining (iv) comprises shining UV light of a wavelength or energy level needed to cure said UV curable chip adhesive, but not release said UV release adhesive.

17. The method of claim 16, wherein said differential response comprises responses to UV light of different energy and wherein said shining (iv) comprises shining UV light of a lower energy sufficient to cure said UV curable chip adhesive but not release said UV release adhesive.

18. The method of claim 15, wherein said support plate comprises a glass plate and said release film comprises a polyester film with said UV release adhesive disposed thereon.

19. The method of claim 8, wherein said providing (i) comprises securing said release film to said main surface of said support plate using roll lamination, wherein said release film includes a release adhesive.

20. The method of claim 8, further comprising applying a structural material surrounding and physically contacting at least one side surface of each chip of said plurality of chips to mechanically interconnect in spaced, planar relationship said plurality of chips, and attaching a process carrier to a planar main surface defined by lapping said structural material and said at least one integrated circuit chip, said attaching employing a permanent process adhesive.

21. A method for temporarily holding an object, said method comprising:

(i) providing a support plate with a release film secured to a surface thereof, said support plate and release film allowing UV light to pass therethrough;

(ii) providing an adhesive composition disposed over said release film, said adhesive composition comprising (a) from about 100 to 150 parts by weight of a UV transparent oligomer;

(b) from about 110 to 330 parts by weight of an inert solvent;

(c) from about 5 to 20 parts by weight of a photoinitiator; and

(d) sufficient wetting agent to wet the substrate without interfering with the surface adhesion of the composition;

(iii) placing said object in contact with said adhesive;

(iv) shining UV light of a first wavelength and energy level through said support plate and release film to cure said adhesive, thereby holding said object where placed;

(v) carrying out additional process steps; and

(vi) shining UV light of a second wavelength and energy level through said support plate and release film to degrade said adhesive and allow separation of said object from said release film and said plate.

22. A method according to claim 21, wherein said inert solvent is chosen from esters, ethers and ether-esters.

23. A method according to claim 21, wherein said first and second wavelengths of UV light are the same and the energy levels are different.

24. A method according to claim 21, wherein said first and second wavelengths of UV light are different.

25. A method according to claim 21, comprising:

(i) providing a support plate with a release film secured to a surface thereof, said support plate and release film allowing UV light to pass therethrough;

(ii) providing an adhesive disposed over said release film, said adhesive comprising (a) about 120 parts by weight of a urethane acrylate oligomer;

(b) about 225 parts by weight of propylene glycol monomethyl ether acetate;

(c) about 10 parts by weight of a photoinitiator; and

(d) about 0.03 parts by weight of a wetting agent;

(iii) placing said object in contact with said adhesive;

(iv) shining UV light of 365 to 480 nm and 75 to 200 m/cm² through said support plate and release film to cure said adhesive, thereby holding said object where placed;

(v) carrying out additional process steps; and

(vi) shining UV light of 365 nm and 3 Joules/cm² or greater through said support plate and release film to degrade said adhesive and allow separation of said object from said release film and said plate.