Copper bonding compatible bond pad structure and method

• US 8,753,972 B2
• Filed: 11/17/2011
• Issued: 06/17/2014
• Est. Priority Date: 05/31/2006
• Status: Active Grant

• Current Assignee: Alpha & Omega Semiconductor, Ltd.
• Original Assignee: Alpha & Omega Semiconductor, Ltd.
• Inventors: Hbert, Franois, Bhalia, Anup
• Primary Examiner(s): CHU, CHRIS C
• Application Number:
  US13/298,455
• Publication Number:
  US 20120064711A1
• Time in Patent Office: 943 Days
• Field of Search: 257/E23.037, 257/E23.015, 257/E23.02, 257/778, 257780-782, 257/784, 257/786, 438/108, 438/617, 438/666, 438/612, 438/614, 438/624, 298/79
• US Class Current: 438/617
• CPC Class Codes: H01L 2224/02166 Collar structures
• CPC Class Codes: H01L 2224/04042 Bonding areas specifically adapted for wire connectors, e.g. wirebond pads
• CPC Class Codes: H01L 2224/05017 comprising protrusions or indentations
• CPC Class Codes: H01L 2224/05073 Single internal layer
• 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 2224/05556 in side view
• CPC Class Codes: H01L 2224/05624 Aluminium [Al] as principal constituent
• CPC Class Codes: H01L 2224/0603 Bonding areas having different sizes, e.g. different heights or widths
• CPC Class Codes: H01L 2224/45124 Aluminium (Al) as principal constituent
• CPC Class Codes: H01L 2224/45144 Gold (Au) as principal constituent
• CPC Class Codes: H01L 2224/45147 Copper (Cu) as principal constituent
• CPC Class Codes: H01L 2224/4807 of bonding interfaces, e.g. interlocking features
• CPC Class Codes: H01L 2224/48453 of the interface with the bonding area
• CPC Class Codes: H01L 2224/48463 the connecting portion on the bonding area of the semiconductor or solid-state body being a ball bond
• CPC Class Codes: H01L 2224/48624 Aluminium (Al) as principal constituent
• CPC Class Codes: H01L 2224/48724 Aluminium (Al) as principal constituent
• CPC Class Codes: H01L 2224/48824 Aluminium (Al) as principal constituent
• CPC Class Codes: H01L 2224/85201 Compression bonding
• CPC Class Codes: H01L 24/03 Manufacturing methods
• CPC Class Codes: H01L 24/05 : of an individual bonding area
• 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 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 2924/00014 : 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 2924/01014 : Silicon [Si]
• CPC Class Codes: H01L 2924/01022 : Titanium [Ti]
• CPC Class Codes: H01L 2924/01029 : Copper [Cu]
• CPC Class Codes: H01L 2924/01033 : Arsenic [As]
• CPC Class Codes: H01L 2924/01068 : Erbium [Er]
• 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 2924/13091 : Metal-Oxide-Semiconductor Field-Effect Transistor [MOSFET]
• CPC Class Codes: Y10T 29/49213 : Metal

Abstract

A copper bonding compatible bond pad structure and associated method is disclosed. The device bond pad structure includes a buffering structure formed of regions of interconnect metal and regions of non-conductive passivation material, the buffering structure providing buffering of underlying layers and structures of the device.

Claims

1. A method of forming a Cu bonding compatible bond pad structure comprising the steps of:

depositing passivation material upon said bond pad structure;

patterning a buffering structure pattern on said passivation material to provide a plurality of spaced-apart regions of said passivation material spaced-apart along a first direction, defining a plurality of hiatuses, portions of said bond pad structure in superimposition with said hiatuses being exposed and spaced-apart from a crown surface of said regions along a second direction, extending transversely to said first direction;

etching said buffering structure pattern to create said Cu bonding compatible bond pad structure; and

attaching a bond wire to a top of said buffer structure pattern pushing a portion of the buffer structure pattern downward for the bond wire connecting to a metal layer underneath the buffer structure pattern.