Method for connecting electronic parts

• US 20040020045A1
• Filed: 07/30/2003
• Published: 02/05/2004
• Est. Priority Date: 01/31/2001
• Status: Active Grant

• Current Assignee: Furukawa Electric Company Limited
• Original Assignee: Furukawa Electric Company Limited
• Inventors: Hirano, Junya
• Granted Patent: US 7,721,425 B2
• Time in Patent Office: Days
• US Class Current: 29/846
• CPC Class Codes: B23K 35/001 Interlayers, transition pieces for metallurgical bonding of workpieces
• CPC Class Codes: C23C 18/32 Coating with nickel, cobalt or mixtures thereof with phosphorus or boron C23C18/50 takes precedence
• CPC Class Codes: H01L 21/288 from a liquid, e.g. electrolytic deposition
• CPC Class Codes: H01L 2224/05001 Internal layers
• CPC Class Codes: H01L 2224/05022 the internal layer being at least partially embedded in the surface
• CPC Class Codes: H01L 2224/05124 Aluminium [Al] as principal constituent
• CPC Class Codes: H01L 2224/05147 Copper [Cu] as principal constituent
• CPC Class Codes: H01L 2224/05568 the whole external layer protruding from the surface
• CPC Class Codes: H01L 2224/05572 the external layer extending out of an opening
• CPC Class Codes: H01L 2224/05655 Nickel [Ni] as principal constituent
• CPC Class Codes: H01L 2224/13099 Material
• CPC Class Codes: H01L 2224/13111 Tin [Sn] as principal constituent
• CPC Class Codes: H01L 23/49816 Spherical bumps on the substrate for external connection, e.g. ball grid arrays [BGA]
• CPC Class Codes: H01L 24/03 Manufacturing methods
• CPC Class Codes: H01L 24/05 of an individual bonding area
• CPC Class Codes: H01L 24/11 Manufacturing methods for bumps on insulating substrates H01L21/4853
• CPC Class Codes: H01L 24/12 Structure, shape, material or disposition of the bump connectors prior to the connecting process
• CPC Class Codes: H01L 24/13 of an individual bump connector
• 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 2924/01012 : Magnesium [Mg]
• CPC Class Codes: H01L 2924/01013 : Aluminum [Al]
• CPC Class Codes: H01L 2924/01015 : Phosphorus [P]
• CPC Class Codes: H01L 2924/01027 : Cobalt [Co]
• 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 2924/01046 : Palladium [Pd]
• CPC Class Codes: H01L 2924/01047 : Silver [Ag]
• CPC Class Codes: H01L 2924/01078 : Platinum [Pt]
• 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: H05K 2203/072 : Electroless plating, e.g. finish plating or initial plating
• CPC Class Codes: H05K 3/244 : Finish plating of conductors, especially of copper conductors, e.g. for pads or lands selective plating methods H05K3/243; finish plating of conductors made by printing techniques H05K3/246; solder as finish H05K3/3457, e.g. by plating H05K3/3473
• CPC Class Codes: H05K 3/3463 : Solder compositions in relation to features of the printed circuit board or the mounting process
• CPC Class Codes: Y10T 29/4913 : Assembling to base an electrical component, e.g., capacitor, etc.
• CPC Class Codes: Y10T 29/49144 : by metal fusion
• CPC Class Codes: Y10T 29/49155 : Manufacturing circuit on or in base

Abstract

A method of connecting an electronic part, containing: forming an electroless nickel plating coat containing phosphorous on a substrate metal layer which constitutes a connecting terminal of an electronic part; and carrying out connecting to the nickel plating coat through a lead-free solder, wherein a half-width of X-ray diffraction of a (111) plane of Ni crystal in the nickel plating coat is 5 degrees or less.

Claims

1. A method of connecting an electronic part, comprising:

forming an electroless nickel plating coat containing phosphorous on a substrate metal layer which constitutes a connecting terminal of an electronic part; and

carrying out connecting to the nickel plating coat through a lead-free solder,

wherein a half-width of X-ray diffraction of a (111) plane of Ni crystal in the nickel plating coat is 5 degrees or less.

2. The connecting method according to claim 1, wherein the plating coat is formed using an electroless nickel plating solution containing 5.5 mass % or less of phosphorous.

3. The connecting method according to claim 1, wherein the plating coat is formed using an electroless nickel plating solution containing 4.5 mass % or less of phosphorous.

4. The connecting method according to claim 1, wherein the X-ray diffraction half-width of the (111) plane of Ni crystal of the nickel plating coat is within a range of 4 degrees to 2 degrees.

5. The connecting method according to claim 1, wherein annealing is carried out at a temperature of 150°

C. or more, after the electroless nickel plating coat is formed.

6. The connecting method according to claim 1, wherein annealing is carried out at a temperature of 250°

C. to 400°

C., after the electroless nickel plating coat is formed.