Ceramic substrate part and electronic part comprising it

• US 8,064,219 B2
• Filed: 09/26/2007
• Issued: 11/22/2011
• Est. Priority Date: 09/26/2006
• Status: Active Grant

• Current Assignee: Proterial Ltd.
• Original Assignee: Hitachi Metals Limited (Hitachi Metals (Thailand) Ltd.)
• Inventors: Taniguchi, Fumitake
• Primary Examiner(s): Chen; Xiaoliang
• Application Number:
  US12/442,616
• Publication Number:
  US 20100302748A1
• Time in Patent Office: 1,518 Days
• Field of Search: 361/772, 174/250, 174/255, 174/257, 174/262, 427/123, 427/165, 427/537, 428/209, 428/447, 428/607, 428/680, 428/704, 438/63, 438/99, 438/149, 438/667, 438/678, 257/66, 257/106, 257/712, 257/737, 257/778, 205/67, 205/70, 205/163
• US Class Current: 361/772
• CPC Class Codes: H01L 2224/05599 Material
• CPC Class Codes: H01L 2224/32225 the item being non-metallic, e.g. insulating substrate with or without metallisation
• CPC Class Codes: H01L 2224/45015 being circular
• CPC Class Codes: H01L 2224/45144 Gold (Au) as principal constituent
• CPC Class Codes: H01L 2224/48091 Arched
• CPC Class Codes: H01L 2224/48227 connecting the wire to a bond pad of the item
• CPC Class Codes: H01L 2224/73265 Layer and wire connectors
• CPC Class Codes: H01L 23/15 Ceramic or glass substrates H01L23/142, H01L23/145, H01L23/147 take precedence
• CPC Class Codes: H01L 23/3677 Wire-like or pin-like cooling fins or heat sinks
• CPC Class Codes: H01L 23/498 Leads, i.e. metallisations or lead-frames on insulating substrates, e.g. chip carriers shape of the substrate H01L23/13
• CPC Class Codes: H01L 23/49822 Multilayer substrates multilayer metallisation on monolayer substrate H01L23/498
• CPC Class Codes: H01L 23/49866 characterised by the materials materials of the substrates H01L23/14, of the lead-frames H01L23/49579
• CPC Class Codes: H01L 24/45 of an individual wire 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 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 2924/00015 the subject-matter covered by the group, the symbol of which is combined with the symbol of this group, being disclosed as prior art
• CPC Class Codes: H01L 2924/01046 Palladium [Pd]
• CPC Class Codes: H01L 2924/01078 Platinum [Pt]
• CPC Class Codes: H01L 2924/01079 : Gold [Au]
• CPC Class Codes: H01L 2924/181 : Encapsulation
• CPC Class Codes: H01L 2924/19041 : being a capacitor
• CPC Class Codes: H01L 2924/19105 : in a side-by-side arrangement on a common die mounting substrate
• CPC Class Codes: H01L 2924/2076 : equal to or larger than 100 microns
• CPC Class Codes: H05K 1/0306 : Inorganic insulating substrates, e.g. ceramic, glass
• CPC Class Codes: H05K 1/092 : Dispersed materials, e.g. conductive pastes or inks
• CPC Class Codes: H05K 2201/0347 : Overplating, e.g. for reinforcing conductors or bumps; Plating over filled vias
• CPC Class Codes: H05K 2203/049 : Wire bonding
• 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 3/246 : Reinforcing conductive paste, ink or powder patterns by other methods, e.g. by plating
• CPC Class Codes: Y10T 428/12438 : Composite
• CPC Class Codes: Y10T 428/12944 : Ni-base component
• CPC Class Codes: Y10T 428/24917 : including metal layer
• CPC Class Codes: Y10T 428/31663 : As siloxane, silicone or silane

Abstract

A ceramic substrate part comprising on its upper surface pluralities of external electrodes comprising wire-bonding electrodes, each of which comprises a primer layer based on Ag or Cu, a Ni-based lower layer, an intermediate layer based on a Pd—P alloy containing 0.4-5% by mass of P, and a Au-based upper layer formed in this order on a ceramic substrate, the upper layer containing Pd after heated by soldering, and having a Au concentration of 80 atomic % or more based on the total concentration (100 atomic %) of Au and Pd.

Claims

1. A ceramic substrate part comprising on its upper surface pluralities of external electrodes comprising wire-bonding electrodes, each of which comprises a primer layer based on Ag or Cu, a Ni-based lower layer, an intermediate layer based on a Pd—

P alloy containing 0.4-5% by mass of P, and a Au-based upper layer formed in this order on a ceramic substrate, said upper layer containing Pd after heated by soldering, and having a Au concentration of 80 atomic % or more based on the total concentration (100 atomic %) of Au and Pd.

2. The ceramic substrate part according to claim 1, wherein said intermediate layer has a P content of 1.2-4% by mass, and said upper layer has a Au concentration of 85 atomic % or more.

3. The ceramic substrate part according to claim 1, wherein said intermediate layer has a thickness of 0.05-0.2 μ

m.

4. The ceramic substrate part according to claim 1, wherein said upper layer has a thickness of 0.03-0.2 μ

m.

5. The ceramic substrate part according to claim 1, wherein part of said external electrodes are mounting electrodes, to which devices are connected by soldering.

6. An electronic part comprising the ceramic substrate part recited in claim 1, and semiconductor devices mounted on said ceramic substrate part, said semiconductor devices being connected to said wire-bonding electrodes with gold wires.