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Process for Removing a Chip/Die Device Affixed with Epoxy on a Ceramic Substrate

IP.com Disclosure Number: IPCOM000113580D
Original Publication Date: 1994-Sep-01
Included in the Prior Art Database: 2005-Mar-27
Document File: 2 page(s) / 72K

Publishing Venue

IBM

Related People

Damiot, P: AUTHOR [+2]

Abstract

This process can be used to remove chips affixed onto a ceramic substrate by an encapsulating epoxy material. The epoxy is used to prevent chip contamination. It cannot be removed by standard wet processes.

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Process for Removing a Chip/Die Device Affixed with Epoxy on a Ceramic
Substrate

      This process can be used to remove chips affixed onto a ceramic
substrate by an encapsulating epoxy material.  The epoxy is used to
prevent chip contamination.  It cannot be removed by standard wet
processes.

      The new method do not need the several hours manual polishing
that has been needed so far and is based upon the fact the ceramic is
known to be in sensitive to chemicals.  It will be described by
reference to the attached drawings.  Fig. 1(A) shows a schematic view
of a conventional ceramic module wherein the chip is encapsulated in
epoxy.

The new method comprises six steps:
  o  Step 1: Remove cap with cutting pliers (Fig. 1(B)).
  o  Step 2: Cut the pins of the module with cutting pliers
             (Fig. 1(C)).
  o  Step 3: Cut out the ceramic around the chip with string saw
             (Fig. 1 (D)).
  o  Step 4: Load the module in a Microware Plasma Etcher MDS 150
             PLASSYS.  Etching conditions microwave discharge power:
             850 Watts, biasing of the substrate with an LF generator
             70 Watts, frequency 210 khz, Bias voltage 90V, reflected
             power 15W, gas O2 20cc flow, etching time 6mns.
  o  Step 5: The module is loaded backside on cooling
electrode(10>c).

      The purpose of etching is to decompose the epoxy between the
ceramic...