Low Pressure Sintering Powder

• US 20170033073A1
• Filed: 04/10/2015
• Published: 02/02/2017
• Est. Priority Date: 04/11/2014
• Status: Active Grant

• Current Assignee: Alpha Assembly Solutions Inc. (Element Solutions Inc)
• Original Assignee: Alpha Metals Inc (Element Solutions Inc)
• Inventors: GHOSHAL, Shamik, CHAKI, Nirmalya Kumar, ROY, Poulami Sengupta, SARKAR, Siuli, RUSTOGI, Anubhav
• Granted Patent: US 10,998,284 B2
• Time in Patent Office: Days
• US Class Current: 1/1
• CPC Class Codes: B22F 1/052 characterised by a mixture of particles of different sizes or by the particle size distribution
• CPC Class Codes: B22F 1/102 Metallic powder coated with organic material
• CPC Class Codes: B22F 1/107 containing organic material comprising solvents, e.g. for slip casting
• CPC Class Codes: B22F 1/17 Metallic particles coated with metal
• CPC Class Codes: B22F 2007/047 non-pressurised baking of the paste or slurry containing metal powder
• CPC Class Codes: B22F 2301/255 Silver or gold
• CPC Class Codes: B22F 2302/45 Others, including non-metals
• CPC Class Codes: B22F 7/04 with one or more layers not made from powder, e.g. made from solid metal
• CPC Class Codes: B22F 7/064 using an intermediate powder layer
• CPC Class Codes: B23K 1/0016 Brazing of electronic components
• CPC Class Codes: B23K 2101/40 Semiconductor devices
• CPC Class Codes: B23K 2103/56 semiconducting semiconducting devices B23K2101/40
• CPC Class Codes: B23K 35/025 Pastes, creams, slurries
• CPC Class Codes: B23K 35/3006 Ag as the principal constituent
• CPC Class Codes: B23K 35/3601 with inorganic compounds as principal constituents
• CPC Class Codes: B23K 35/3613 Polymers, e.g. resins
• CPC Class Codes: B23K 35/3618 Carboxylic acids or salts
• CPC Class Codes: B23K 35/365 Selection of non-metallic compositions of coating materials either alone or conjoint with selection of soldering or welding materials
• CPC Class Codes: H01B 1/22 the conductive material comprising metals or alloys
• CPC Class Codes: H01L 2224/0401 Bonding areas specifically adapted for bump connectors, e.g. under bump metallisation [UBM]
• CPC Class Codes: H01L 2224/04026 : Bonding areas specifically adapted for layer connectors
• 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 2224/11 : Manufacturing methods
• CPC Class Codes: H01L 2224/11003 : for holding or transferring the bump preform
• CPC Class Codes: H01L 2224/1132 : Screen printing, i.e. using a stencil
• CPC Class Codes: H01L 2224/11334 : using preformed bumps
• CPC Class Codes: H01L 2224/11436 : Lamination of a preform, e.g. foil, sheet or layer
• CPC Class Codes: H01L 2224/131 : 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
• CPC Class Codes: H01L 2224/13339 : Silver [Ag] as principal constituent
• CPC Class Codes: H01L 2224/13347 : Copper [Cu] as principal constituent
• CPC Class Codes: H01L 2224/13355 : Nickel [Ni] as principal constituent
• CPC Class Codes: H01L 2224/13387 : Ceramics, e.g. crystalline carbides, nitrides or oxides glass ceramics H01L2224/13388
• CPC Class Codes: H01L 2224/1339 : with a principal constituent of the material being a polymer, e.g. polyester, phenolic based polymer, epoxy
• CPC Class Codes: H01L 2224/13439 : Silver [Ag] as principal constituent
• CPC Class Codes: H01L 2224/1349 : with a principal constituent of the material being a polymer, e.g. polyester, phenolic based polymer, epoxy
• CPC Class Codes: H01L 2224/13499 : Shape or distribution of the fillers
• CPC Class Codes: H01L 2224/16227 : the bump connector connecting to a bond pad of the item
• CPC Class Codes: H01L 2224/27 : Manufacturing methods
• CPC Class Codes: H01L 2224/27003 : for holding or transferring the layer preform
• CPC Class Codes: H01L 2224/271 : Manufacture and pre-treatment of the layer connector preform
• CPC Class Codes: H01L 2224/27332 : using a powder
• CPC Class Codes: H01L 2224/27436 : Lamination of a preform, e.g. foil, sheet or layer
• CPC Class Codes: H01L 2224/27505 : Sintering
• CPC Class Codes: H01L 2224/2929 : with a principal constituent of the material being a polymer, e.g. polyester, phenolic based polymer, epoxy
• CPC Class Codes: H01L 2224/29339 : Silver [Ag] as principal constituent
• CPC Class Codes: H01L 2224/29347 : Copper [Cu] as principal constituent
• CPC Class Codes: H01L 2224/29355 : Nickel [Ni] as principal constituent
• CPC Class Codes: H01L 2224/29387 : Ceramics, e.g. crystalline carbides, nitrides or oxides glass ceramics H01L2224/29388
• CPC Class Codes: H01L 2224/2939 : with a principal constituent of the material being a polymer, e.g. polyester, phenolic based polymer, epoxy
• CPC Class Codes: H01L 2224/29439 : Silver [Ag] as principal constituent
• CPC Class Codes: H01L 2224/2949 : with a principal constituent of the material being a polymer, e.g. polyester, phenolic based polymer, epoxy
• CPC Class Codes: H01L 2224/29499 : Shape or distribution of the fillers
• CPC Class Codes: H01L 2224/32145 : the bodies being stacked
• CPC Class Codes: H01L 2224/32146 : the layer connector connecting to a via connection in the semiconductor or solid-state body
• CPC Class Codes: H01L 2224/32225 : the item being non-metallic, e.g. insulating substrate with or without metallisation
• CPC Class Codes: H01L 2224/32245 : the item being metallic
• CPC Class Codes: H01L 2224/45099 : Material
• CPC Class Codes: H01L 2224/48227 : connecting the wire to a bond pad of the item
• CPC Class Codes: H01L 2224/48247 : connecting the wire to a bond pad of the item
• CPC Class Codes: H01L 2224/73265 : Layer and wire connectors
• CPC Class Codes: H01L 2224/81 : using a bump connector
• CPC Class Codes: H01L 2224/81075 : being inert
• CPC Class Codes: H01L 2224/81192 : wherein the bump connectors are disposed only on another item or body to be connected to the semiconductor or solid-state body
• CPC Class Codes: H01L 2224/81203 : Thermocompression bonding, e.g. diffusion bonding, pressure joining, thermocompression welding or solid-state welding
• CPC Class Codes: H01L 2224/8121 : using a reflow oven
• CPC Class Codes: H01L 2224/8184 : Sintering
• CPC Class Codes: H01L 2224/81948 : Thermal treatments, e.g. annealing, controlled cooling
• CPC Class Codes: H01L 2224/83 : using a layer connector
• CPC Class Codes: H01L 2224/83075 : being inert
• CPC Class Codes: H01L 2224/83191 : wherein the layer connectors are disposed only on the semiconductor or solid-state body
• CPC Class Codes: H01L 2224/83192 : wherein the layer connectors are disposed only on another item or body to be connected to the semiconductor or solid-state body
• CPC Class Codes: H01L 2224/83203 : Thermocompression bonding, e.g. diffusion bonding, pressure joining, thermocompression welding or solid-state welding
• CPC Class Codes: H01L 2224/8321 : using a reflow oven
• CPC Class Codes: H01L 2224/83439 : Silver [Ag] as principal constituent
• CPC Class Codes: H01L 2224/83447 : Copper [Cu] as principal constituent
• CPC Class Codes: H01L 2224/8384 : Sintering
• CPC Class Codes: H01L 2224/83948 : Thermal treatments, e.g. annealing, controlled cooling
• CPC Class Codes: H01L 2224/92247 : the second connecting process involving a wire 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 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 24/16 : of an individual bump connector
• CPC Class Codes: H01L 24/27 : Manufacturing methods
• CPC Class Codes: H01L 24/29 : of an individual layer connector
• CPC Class Codes: H01L 24/32 : of an individual layer connector
• CPC Class Codes: H01L 24/48 : of an individual wire connector
• CPC Class Codes: H01L 24/73 : Means for bonding being of different types provided for in two or more of groups H01L24/10, H01L24/18, H01L24/26, H01L24/34, H01L24/42, H01L24/50, H01L24/63, H01L24/71
• CPC Class Codes: H01L 24/81 : using a bump connector
• CPC Class Codes: H01L 24/83 : using a layer connector
• CPC Class Codes: H01L 24/92 : Specific sequence of method steps
• CPC Class Codes: H01L 25/50 : Multistep manufacturing processes of assemblies consisting of devices, each device being of a type provided for in group H01L27/00 or H01L29/00 H01L21/50 takes precedence
• 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 2924/00012 : Relevant to the scope of the group, the symbol of which is combined with the symbol of this group
• 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 2924/01004 : Beryllium [Be]
• CPC Class Codes: H01L 2924/01028 : Nickel [Ni]
• CPC Class Codes: H01L 2924/01029 : Copper [Cu]
• CPC Class Codes: H01L 2924/0103 : Zinc [Zn]
• CPC Class Codes: H01L 2924/01046 : Palladium [Pd]
• CPC Class Codes: H01L 2924/01047 : Silver [Ag]
• CPC Class Codes: H01L 2924/0105 : Tin [Sn]
• CPC Class Codes: H01L 2924/01074 : Tungsten [W]
• CPC Class Codes: H01L 2924/0493 : 3rd Group
• CPC Class Codes: H01L 2924/0665 : Epoxy resin
• CPC Class Codes: H01L 2924/12041 : LED
• CPC Class Codes: H01L 2924/12044 : OLED
• CPC Class Codes: H01L 2924/1461 : MEMS
• CPC Class Codes: H01L 2924/20102 : Temperature range 0 C=<T<60 C, 273.15 K =<T< 333.15K
• CPC Class Codes: H01L 2924/20103 : Temperature range 60 C=<T<100 C, 333.15 K =< T< 373.15K
• CPC Class Codes: H01L 2924/20104 : Temperature range 100 C=<T<150 C, 373.15 K =< T < 423.15K
• CPC Class Codes: H01L 2924/20105 : Temperature range 150 C=<T<200 C, 423.15 K =< T < 473.15K
• CPC Class Codes: H01L 2924/20106 : Temperature range 200 C=<T<250 C, 473.15 K =<T < 523.15K
• CPC Class Codes: H01L 2924/20107 : Temperature range 250 C=<T<300 C, 523.15K =<T< 573.15K
• CPC Class Codes: H01L 2924/20108 : Temperature range 300 C=<T<350 C, 573.15K =<T< 623.15K
• CPC Class Codes: H01L 2924/20109 : Temperature range 350 C=<T<400 C, 623.15K =<T< 673.15K
• CPC Class Codes: H01L 2924/2011 : Temperature range 400 C=<T<450 C, 673.15K =<T< 723.15K
• CPC Class Codes: H01L 2924/206 : Length ranges
• CPC Class Codes: H01L 2924/2064 : larger or equal to 1 micron less than 100 microns
• CPC Class Codes: H05K 3/321 : by conductive adhesives
• CPC Class Codes: H10K 50/8426 : Peripheral sealing arrangements, e.g. adhesives, sealants

Abstract

A sintering powder comprising:

• • a first type of metal particles having a mean longest dimension of from 100 nm to 50 μm.

Claims

1. A sintering powder comprising:

a first type of metal particles having a mean longest dimension of from 100 nm to 50 μ

m.

2. The sintering powder of claim 1, wherein at least a portion of the first type of metal particles are at least partially coated with a capping agent comprising a carboxylate and/or amine functional group.

3. The sintering powder of claim 1, wherein the capping agent of the first type of metal particles comprises a straight chain or branched chain aliphatic acid.

4. The sintering powder of claim 1, comprising up to 5 wt % capping agent.

6. The sintering powder of claim 1, wherein the first type of metal particles has a D50 of from 1 to 3 μ

m.

7. The sintering powder of claim 1, wherein the first type of metal particles has a tap density of from 3.5 to 5.5 g/cc.

8. The sintering powder of claim 1, further comprising a second type of metal particles having a mean longest dimension of less than 100 nm, wherein the second type of metal particles are at least partially coated with a capping agent.

9. The sintering powder of claim 8, wherein the second type of metal particles has a mean longest dimension of from 5 to 75 nm.

10. The sintering powder of claim 8 comprising from 1 to 19 wt % of the first type of metal particles and from 81 to 99 wt % of the second type of metal particles.

11. The sintering powder of claim 1 wherein the first type of metal particles and/or second type of metal particles comprises silver or an alloy or core-shell structures of silver coated particles thereof.

12. The sintering powder of claim 8, wherein the capping agent of the second type of metal particles comprises an amine and/or a carboxylate functional group.

13. The sintering powder of claim 8 wherein the capping agent of the second type of metal particles comprises a straight chain or branched chain aliphatic amine.

14. The sintering powder of claim 1 comprising:

from 1 to 10 wt % of a first type of metal particles having a mean longest dimension of from 100 nm to 20 μ

m, the metal particles at least partially coated with a coated with an oleic acid capping agent; and

from 90 to 99 wt % of a second type of metal particles having a mean longest dimension of from 5 to 75 nm, wherein the second type of metal particles are at least partially coated with an octylamine capping agent.

17. The sintering powder of claim 8, wherein the second type of metal particles has a mean longest dimension of from 500 nm to 5 μ

m.

46. The sintering powder of claim 4, comprising 0.1 to 3 wt % capping agent.

47. The sintering powder of claim 10, comprising from 5 to 15 wt % of the first type of metal particles and from 85 to 95 wt % of the second type of metal particles.

5. (canceled)

15. (canceled)

16. (canceled)

18. (canceled)

19. (canceled)

20. (canceled)

21. (canceled)

22. A sintering paste comprising:

a sintering powder comprising metal particles having a mean longest dimension of less than 100 nm, wherein at least some of the metal particles are at least partially coated with a capping agent;

a solvent; and

optionally, at least one of a binder, a rheology modifier, an organosilver compound, an activator, a surfactant, a wetting agent, hydrogen peroxide, or organic peroxides.

23. The sintering paste of claim 22 wherein the binder is present and comprises an epoxy-based resin.

24. The sintering paste of claim 22 wherein the solvent comprises at least one of a monoterpene alcohol, a glycol, or glycol ether.

25. The sintering paste of claim 22, comprising:

from 1 to 15 wt % binder; and

/or

from 1 to 30 wt % solvent; and

/or

up to 5 wt % rheology modifier; and

/or

up to 10 wt % an organosilver compound; and

/or

up to 2 wt % activator; and

/or

up to 6 wt % surfactant; and

/or

up to 2 wt % hydrogen peroxide or organic peroxides.

27. The sintering paste of claim 22 comprising:

from 1 to 30 wt % solvent; and

/or

up to 50 wt % organosilver compound; and

/or

up to 5 wt % rheology modifier; and

/or

up to 2 wt % activator; and

/or

up to 6 wt % surfactant; and

/or

up to 2 wt % hydrogen peroxide or organic peroxides.

28. The sintering paste of claim 22, wherein the organosilver compound is present and comprises one or more of silver oxalate, silver lactate, silver succinate, silver neodecanoate, silver citrate and silver stearate.

29. The sintering paste of any of claim 22, further comprising at least one of a fatty acid or a wetting agent.

31. The sintering paste of claim 22, wherein the paste is substantially resin free.

33. The sintering paste of any of claim 22, further comprising a film forming agent.

48. The sintering paste of claim 29, wherein the fatty acid comprises one or more of:

short or long chain (C=2 to

     30) carboxylic acids or di-carboxylic acids or hydroxyl carboxylic acids;

or

short or long chain (C=2 to

     30) amines.

26. (canceled)

30. (canceled)

32. (canceled)

34. (canceled)

35. A method of die attachment comprising:

(i) placing a sintering film comprising a sintering powder comprising metal particles having a mean longest dimension of less than 100 nm, wherein at least some of the metal particles are at least partially coated with a capping agent and a binder between a die and a substrate to be joined; and

(ii) sintering the sintering film.

36. The method of claim 35, wherein the sintering is carried out at a temperature of from 150 to 400°

C. for up to 120 minutes.

37. The method of claim 35, wherein step (i) comprises:

(a) applying the sintering film to the die to form an assembly having a die side and a sintering film side; and

(b) contacting the sintering film side of the assembly with the substrate.

38. The method of claim 37, wherein step (a) is carried out at a temperature of from 15 to 400°

C. and a pressure of from 0.1 to 5 MPa for from 0.1 to 60 seconds.

39. The method of claim 37, wherein step (b) is carried out at a temperature of from 15 to 400°

C. and a pressure of from 0.1 to 40 MPa for from 0.1 to 60 minutes.

40. The method of claim 35, wherein the sintering is carried out while applying a pressure of from 0.1 to 40 MPa.

49. The method of claim 35, wherein the sintering is carried out without the application of pressure.

41. A method of wafer bonding comprising:

(i) placing a sintering film comprising a sintering powder comprising metal particles having a mean longest dimension of less than 100 nm, wherein at least some of the metal particles are at least partially coated with a capping agent and a binder between two or more wafers to be joined; and

(ii) sintering the sintering film,

wherein the sintering is carried out without the application of pressure.

42. A method of transferring a sintering film to a component, comprising:

applying a sintering film comprising a sintering powder comprising metal particles having a mean longest dimension of less than 100 nm, wherein at least some of the metal particles are at least partially coated with a capping agent and a binder to a substrate to form an assembly having a sintering film side and a substrate side;

contacting the sintering film side of the assembly with a component;

heating the assembly to a temperature of from 50 to 200°

C.;

applying a pressure of from 1 to 5 MPa to the assembly for from 0.1 seconds to 60 minutes; and

separating the substrate from the sintering film.

43. (canceled)

44. A method of manufacturing a sintered joint comprising the steps:

providing a sintering film comprising a sintering powder comprising metal particles having a mean longest dimension of less than 100 nm, wherein at least some of the metal particles are at least partially coated with a capping agent and a binder in the vicinity of two or more work pieces to be joined; and

heating the sintering film to at least partially sinter the metal.

45. The method of claim 44 wherein the heating is carried out at a temperature of at least 140°

C.