Browse Prior Art Database

Individual Chip Transfer System

IP.com Disclosure Number: IPCOM000112013D
Original Publication Date: 1994-Apr-01
Included in the Prior Art Database: 2005-Mar-26
Document File: 4 page(s) / 100K

Publishing Venue

IBM

Related People

Edmundson, RJ: AUTHOR [+3]

Abstract

During burn-in testing of logic and memory chips, the chips are soldered onto a test substrate, then desoldered following testing. As a result, the controlled collapse chip contact (C4) solder balls connecting the chips' logic or memory to the computer circuits are deformed, and must be reflowed before the chips are transferred into shipping containers.

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This is the abbreviated version, containing approximately 52% of the total text.

Individual Chip Transfer System

      During burn-in testing of logic and memory chips, the chips are
soldered onto a test substrate, then desoldered following testing.
As a result, the controlled collapse chip contact (C4) solder balls
connecting the chips' logic or memory to the computer circuits are
deformed, and must be reflowed before the chips are transferred into
shipping containers.

      Prior to the automation of this process, operators transferred
the chips manually with vacuum pencils, which was not only time
consuming, but placed the chips and solder balls at risk of damage
from handling.  An automatic tool was needed to transfer chips of
various sizes in an efficient, controlled manner to increase
throughput and eliminate damage.  The individual chip transfer system
met these requirements.

      Disclosed herein is an Individual Chip Transfer System (ICTS)
that uses a stand-alone tool to transfer logic and memory chips from
reflow boats to Linear Device Banks (LDBs) or Chip Banks (CBs) for
shipment.  The ICTS uses a programmable IC chip handler, a chip
carrier fixture, and selectable compliance chip pickup nozzles.  If
alignment or rotation of the chips is required for testing, a chip
alignment fixture for multi-sized chips can also be used.

      Following reflow of the solder balls, the chips in reflow boats
are loaded into a chip carrier fixture (shown in Fig. 2).  This
fixture is designed to accommodate two reflow boats 7, 2 CBs 8, and 2
LDBs 9, so that chips can be transferred from the reflow boats to the
appropriate container for shipment.  (Other fixtures can be used for
applications requiring different carrier configurations.)  The
fixture is then placed on the Y stage of the chip handler, where
dowels hold it in proper alignment.

      The programmable chip handle...