Browse Prior Art Database

Pin Repair of MLC Substrate I/O Pads by Focused Ion Beam Techniques

IP.com Disclosure Number: IPCOM000107921D
Original Publication Date: 1992-Mar-01
Included in the Prior Art Database: 2005-Mar-22
Document File: 1 page(s) / 62K

Publishing Venue

IBM

Related People

Kirch, SJ: AUTHOR [+2]

Abstract

Multi-layer ceramic (MLC) substrates are the current best-of-breed among high-performance chip carriers for midrange and mainframe computer applications. The advanced technology necessary to construct such substrates is associated with a large capital equipment cost. A key to cost-competitiveness is the reduction in unit cost. This is most effectively achieved by improving the production yield of the manufacturing process. This paper proposes a method to repair MLC substrates which have suffered damage to the pins used to connect the substrate to the main second-level packaging board in the computer.

This text was extracted from an ASCII text file.
This is the abbreviated version, containing approximately 62% of the total text.

Pin Repair of MLC Substrate I/O Pads by Focused Ion Beam Techniques

      Multi-layer ceramic (MLC) substrates are the current
best-of-breed among high-performance chip carriers for midrange and
mainframe computer applications.  The advanced technology necessary
to construct such substrates is associated with a large capital
equipment cost.  A key to cost-competitiveness is the reduction in
unit cost.  This is most effectively achieved by improving the
production yield of the manufacturing process.  This paper proposes a
method to repair MLC substrates which have suffered damage to the
pins used to connect the substrate to the main second-level packaging
board in the computer.

      Multi-layer ceramic chip substrates must be scrapped if even a
single input/output (I/O) pin is damaged or lost during routine
processing.  As there may be several thousand pins per substrate, a
considerable fraction of the substrates may be lost in this manner.
We propose to repair damaged I/O pads using a focused ion beam system
to deposit a new pad, or a portion thereof, to repair the damaged
pad(s).  The pin(s) could then be brazed onto the rejuvenated pads,
and the substrate returned to working order.

      Ion-induced metal deposition may be preceded by an
ion-sputtering step to clean or otherwise prepare the surface to
receive the deposited metal.  When the surface has been adequately
prepared, one or more layers of metal may be deposited with the
introduction of an a...