Browse Prior Art Database

Test Vehicle for Testing at Chip Level

IP.com Disclosure Number: IPCOM000105278D
Original Publication Date: 1993-Jul-01
Included in the Prior Art Database: 2005-Mar-19
Document File: 2 page(s) / 36K

Publishing Venue

IBM

Related People

Kerklaan, AJ: AUTHOR

Abstract

Prior to this invention it was necessary to bond an Integrated Circuit chip to its first level packaging substrate in order to facilitate direct chip attachment to a testing device. This can result in waste as faulty chips and their first level attachment material would need to discarding.

This text was extracted from an ASCII text file.
This is the abbreviated version, containing approximately 93% of the total text.

Test Vehicle for Testing at Chip Level

      Prior to this invention it was necessary to bond an Integrated
Circuit chip to its first level packaging substrate in order to
facilitate direct chip attachment to a testing device.  This can
result in waste as faulty chips and their first level attachment
material would need to discarding.

      By bonding a thin layer of copper or other conductive material
to an insulating backing material such as mylar with tractor feed
holes (similar to 35mm film) and then photoengraving and chemical
etching suitable patterns can be generated in a repetitive manner
along the backing material.  Each pattern is designed to provide
lands for the particular type of chip that requires testing, the
lands being connected by copper traces to respective outer pads that
are more widely spaced so that test probes can conveniently access
them to form an electrical connection with desired contacts of the
chip.  The chip to be tested is placed and held onto the inner pads
or lands while test probes contact the outer pads.

      Pliability of the backing material allows sufficient contact
for testing purposes even when there are discrepencies in the
flatness of the contact points on the chip.

      When testing of a chip is completed it is lifted off and
replaced by the next one.

      The pads of the test vehicle will undoubtedly wear after a
number of chips have been tested.  When excessive wear has occurred
the backing materia...