Athmosphere-Controlled Bonding Apparatus, Bonding Method, and Electronic Device

• US 20090272721A1
• Filed: 09/28/2005
• Published: 11/05/2009
• Est. Priority Date: 09/28/2005
• Status: Abandoned Application

• Current Assignee: Tadahiro Ohmi
• Original Assignee: Tadahiro Ohmi
• Inventors: Ohmi, Tadahiro, Morimoto, Akihiro
• Application Number:
  US11/992,667
• Publication Number:
  US 20090272721A1
• Time in Patent Office: Days
• US Class Current: 219/118
• CPC Class Codes: B23K 20/004 Wire welding
• CPC Class Codes: B23K 20/02 by means of a press ; Diffusion bonding B23K20/001, B23K20/04 take precedence
• CPC Class Codes: B23K 20/10 making use of vibrations, e.g. ultrasonic welding
• CPC Class Codes: B23K 2101/40 Semiconductor devices
• CPC Class Codes: H01L 21/67144 Apparatus for mounting on conductive members, e.g. leadframes or conductors on insulating substrates
• CPC Class Codes: H01L 2224/45099 Material
• CPC Class Codes: H01L 2224/48 of an individual wire connector
• CPC Class Codes: H01L 2224/75 Apparatus for connecting with bump connectors or layer connectors
• CPC Class Codes: H01L 2224/78 Apparatus for connecting with wire connectors
• CPC Class Codes: H01L 2224/81203 Thermocompression bonding, e.g. diffusion bonding, pressure joining, thermocompression welding or solid-state welding
• CPC Class Codes: H01L 2224/81205 Ultrasonic bonding
• CPC Class Codes: H01L 2224/81801 Soldering or alloying
• CPC Class Codes: H01L 2224/85 using a wire connector
• CPC Class Codes: H01L 24/75 Apparatus for connecting with bump connectors or layer connectors
• CPC Class Codes: H01L 24/78 Apparatus for connecting with wire connectors
• CPC Class Codes: H01L 24/81 using a bump connector
• CPC Class Codes: H01L 24/85 using a wire connector wire bonding in general B23K20/004
• 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 2924/01005 Boron [B]
• CPC Class Codes: H01L 2924/01006 : Carbon [C]
• CPC Class Codes: H01L 2924/01013 : Aluminum [Al]
• CPC Class Codes: H01L 2924/01024 : Chromium [Cr]
• CPC Class Codes: H01L 2924/01029 : Copper [Cu]
• CPC Class Codes: H01L 2924/0103 : Zinc [Zn]
• CPC Class Codes: H01L 2924/01033 : Arsenic [As]
• CPC Class Codes: H01L 2924/01047 : Silver [Ag]
• CPC Class Codes: H01L 2924/01049 : Indium [In]
• CPC Class Codes: H01L 2924/0105 : Tin [Sn]
• CPC Class Codes: H01L 2924/01079 : Gold [Au]
• CPC Class Codes: H01L 2924/01082 : Lead [Pb]
• CPC Class Codes: H01L 2924/014 : Solder alloys
• CPC Class Codes: H01L 2924/19041 : being a capacitor
• CPC Class Codes: H01L 2924/3025 : Electromagnetic shielding

Abstract

In a bonding apparatus for bonding under pressure a pressure-bonding portion, the concentration of water in a pressure-bonding portion atmosphere inside the apparatus is set smaller than that in an atmosphere outside the apparatus, thereby enabling pressure bonding under low-temperature and low-pressure conditions. In this case, the amount of adsorbed water on each surface of a bonding metal terminal and a to-be-bonded metal terminal forming the pressure-bonding portion is set to 1×10¹⁶ molecules/cm² or less.

Claims

1. A bonding apparatus for electrically bonding under pressure a bonding metal terminal and a to-be-bonded metal terminal to each other, characterized in that a water concentration in an atmosphere in a pressure-bonding portion is set smaller than that in an atmosphere outside the apparatus.

2. The bonding apparatus according to claim 1, wherein an adsorbed water amount on a surface of the bonding metal terminal and a surface of the to-be-bonded metal terminal in the pressure-bonding portion is 1×

10¹⁶ molecules/cm² or less.

3. The bonding apparatus according to claim 1, wherein an adsorbed organic substance amount on a surface of the bonding metal terminal and a surface of the to-be-bonded metal terminal in the pressure-bonding portion is 5×

10¹³ molecules/cm² or less in terms of eicosane weight.

4. The bonding apparatus according to claim 1, wherein the water concentration in the atmosphere in the pressure-bonding portion is set to 10 vol.ppm or less.

5. The bonding apparatus according to claim 1, wherein an oxygen concentration in the atmosphere in the pressure-bonding portion is set to 10 vol.ppm or less.

6. The bonding apparatus according to claim 1, wherein an inert gas is circulated to at least the pressure-bonding portion.

7. The bonding apparatus according to claim 1, wherein a high-purity inert gas in which a concentration of impurities excluding water is 100 vol.ppm or less, a water concentration is 10 vol.ppm or less, and an oxygen concentration is 10 vol.ppm or less is circulated to at least the pressure-bonding portion.

8. The bonding apparatus according to claim 7, wherein the water concentration in said inert gas is 1 vol.ppm or less.

9. The bonding apparatus according to claim 1, wherein said bonding apparatus has a supply port for supplying an inert gas from the outside of the apparatus and a water content in said inert gas at said supply port is 10 vol.ppm or less.

10. The bonding apparatus according to claim 1, wherein an adsorbed water amount on an inner surface of said bonding apparatus is 1×

10¹⁶ molecules/cm² or less.

11. The bonding apparatus according to claim 1, wherein an inner surface of said apparatus is one of an electrolytically polished stainless surface, an electrochemically polished stainless surface, an electrolytically or electrochemically polished surface containing chromium oxide as a main component, an electrolytically or electrochemically polished surface containing aluminum oxide as a main component, a polyolefin-based resin surface, a polycycloolefin-based resin surface, or a fluorine-based resin surface.

12. The bonding apparatus according to claim 1, comprising means for reducing an adsorbed water amount on a surface of said bonding metal terminal and a surface of said to-be-bonded metal terminal to 1×

10¹⁶ molecules/cm² or less.

13. The bonding apparatus according to claim 1, comprising means for reducing an adsorbed organic substance amount on a surface of the bonding metal terminal and a surface of the to-be-bonded metal terminal in the pressure-bonding portion to 5×

10¹³ molecules/cm² or less.

14. The bonding apparatus according to claim 6, wherein said inert gas contains at least one of nitrogen, helium, neon, argon, krypton, and xenon.

15. The bonding apparatus according to claim 6, wherein hydrogen is added to said inert gas.

16. The bonding apparatus according to claim 1, comprising means for neutralizing or removing static electricity generated at least one of said bonding metal terminal, said to-be-bonded metal terminal, and a portion around said pressure-bonding portion.

17. The bonding apparatus according to claim 16, wherein said neutralizing or removing means comprises soft X-ray generation means.

18. A bonding method for electrically bonding under pressure a bonding metal terminal and a to-be-bonded metal terminal to each other, comprising a step of setting a water concentration in an atmosphere in a pressure-bonding portion to be smaller than that in an atmosphere outside an apparatus.

19. The bonding method according to claim 18, comprising a step of performing pressure bonding by setting an adsorbed water amount on a surface of the bonding metal terminal and a surface of the to-be-bonded metal terminal in the pressure-bonding portion to be 1×

10¹⁶ molecules/cm² or less.

20. The bonding method according to claim 18, comprising a step of performing pressure bonding by setting an adsorbed organic substance amount on a surface of the bonding metal terminal and a surface of the to-be-bonded metal terminal in the pressure-bonding portion to be 5×

10¹³ molecules/cm² or less.

21. The bonding method according to claim 18, comprising a step of setting the water concentration in the atmosphere in the pressure-bonding portion to be 10 vol.ppm or less.

22. The bonding method according to claim 18, comprising a step of setting an oxygen concentration in the atmosphere in the pressure-bonding portion to be 10 vol.ppm or less.

23. The bonding method according to claim 18, comprising a step of circulating an inert gas to at least the pressure-bonding portion.

24. The bonding method according to claim 18, comprising a step of circulating a high-purity inert gas in which a concentration of impurities excluding water is 100 vol.ppm or less, a water concentration is 10 vol.ppm or less, and an oxygen concentration is 10 vol.ppm or less, to at least the pressure-bonding portion.

25. The bonding method according to claim 24, comprising a step of setting the water concentration in said inert gas to be 1 vol.ppm or less.

26. The bonding method according to claim 18, comprising a step of performing pressure bonding while shielding said pressure-bonding portion from an external atmosphere, and setting an adsorbed water amount on an inner surface of a shielding portion to be 1×

10¹⁶ molecules/cm² or less.

27. The bonding method according to claim 18, comprising a step of performing pressure bonding while shielding said pressure-bonding portion from an external atmosphere, and setting an adsorbed organic substance amount on an inner surface of a shielding portion to be 5×

10¹³ molecules/cm² or less.

28. The bonding method according to claim 23, wherein said inert gas contains at least one of nitrogen, helium, neon, argon, krypton, and xenon.

29. The bonding method according to claim 23, comprising a step of adding hydrogen to said inert gas.

30. The bonding method according to claim 18, comprising a step of neutralizing or removing static electricity generated at least one of said bonding metal terminal, said to-be-bonded metal terminal, and a portion around said pressure-bonding portion.

31. The bonding method according to claim 30, comprising a step of neutralizing or removing the static electricity using a soft X-ray.

41. An electronic device comprising the metal terminals bonded together using the bonding method according to one of claims 18, 32, or 34.

32. A metal terminal bonding method for electrically bonding under pressure a bonding metal terminal and a to-be-bonded metal terminal to each other, said bonding metal terminal having a surface containing at least one of lead, tin, silver, gold, copper, zinc, aluminum, bismuth, indium, and nickel, and said to-be-bonded metal terminal having a surface containing at least one of lead, tin, silver, gold, copper, zinc, aluminum, bismuth, indium, and nickel, said bonding method comprising a step of forming bonding in a pressure-bonding portion after reducing water adsorbed on surfaces, adapted to form the bonding, to 1×

10¹⁶ molecules/cm² or less and reducing an organic substance amount adsorbed on said surfaces to 5×

10¹³ molecules/cm² or less.

33. (canceled)

34. A bonding method for electrically bonding under pressure a bonding metal terminal and a to-be-bonded metal terminal to each other, characterized by setting an oxygen concentration in the atmosphere in the pressure-bonding portion to be 10 vol.ppm or less.

35. The bonding method according to claim 34, comprising a step of circulating an inert gas to at least the pressure-bonding portion.

36. The bonding method according to claim 34, comprising a step of performing pressure bonding while shielding said pressure-bonding portion from an external atmosphere, and setting an adsorbed water amount on an inner surface of a shielding portion to be 1×

10¹⁶ molecules/cm² or less.

37. The bonding method according to claim 34, comprising a step of performing pressure bonding while shielding said pressure-bonding portion from an external atmosphere, and setting an adsorbed organic substance amount on an inner surface of a shielding portion to be 5×

10¹³ molecules/cm² or less.

38. The bonding method according to claim 34, comprising a step of neutralizing or removing static electricity generated at least one of said bonding metal terminal, said to-be-bonded metal terminal, and a portion around said pressure-bonding portion.

39. The bonding method according to claim 34, comprising a step of performing pressure bonding by setting an adsorbed water amount on a surface of the bonding metal terminal and a surface of the to-be-bonded metal terminal in the pressure-bonding portion to be 1×

10¹⁶ molecules/cm² or less.

40. The bonding method according to claim 34, wherein pressure bonding is performed by setting an adsorbed organic substance amount on a surface of the bonding metal terminal and a surface of the to-be-bonded metal terminal in the pressure-bonding portion to be 5×

10¹³ molecules/cm² or less.

42. A bonding apparatus for electrically bonding under pressure a bonding metal terminal and a to-be-bonded metal terminal to each other, wherein an oxygen concentration in the atmosphere in the pressure-bonding portion is set to 10 vol.ppm or less.

43. The bonding apparatus according to claim 42, wherein an inert gas is circulated to at least the pressure-bonding portion.

44. The bonding apparatus according to claim 42, wherein an adsorbed water amount on an inner surface of said bonding apparatus is 1×

10¹⁶ molecules/cm² or less.

45. The bonding apparatus according to claim 42, wherein an inner surface of said apparatus is one of an electrolytically polished stainless surface, an electrochemically polished stainless surface, an electrolytically or electrochemically polished surface containing chromium oxide as a main component, an electrolytically or electrochemically polished surface containing aluminum oxide as a main component, a polyolefin-based resin surface, a polycycloolefin-based resin surface, or a fluorine-based resin surface.

46. The bonding apparatus according to claim 42, comprising means for reducing an adsorbed water amount on a surface of said bonding metal terminal and a surface of said to-be-bonded metal terminal to 1×

10¹⁶ molecules/cm² or less.

47. The bonding apparatus according to claim 42, comprising means for reducing an adsorbed organic substance amount on a surface of the bonding metal terminal and a surface of the to-be-bonded metal terminal in the pressure-bonding portion to 5×

10¹³ molecules/cm² or less.

48. The bonding apparatus according to claim 42, comprising means for neutralizing or removing static electricity generated at least one of said bonding metal terminal, said to-be-bonded metal terminal, and a portion around said pressure-bonding portion.