Browse Prior Art Database

Hermetic Seal Using Partially Cured Adhesive

IP.com Disclosure Number: IPCOM000100789D
Original Publication Date: 1990-Jun-01
Included in the Prior Art Database: 2005-Mar-16
Document File: 1 page(s) / 30K

Publishing Venue

IBM

Related People

Besse, JF: AUTHOR [+2]

Abstract

Disclosed is a two-step process of curing adhesive for hermetically sealed packaging.

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This is the abbreviated version, containing approximately 100% of the total text.

Hermetic Seal Using Partially Cured Adhesive

       Disclosed is a two-step process of curing adhesive for
hermetically sealed packaging.

      Conventionally, electronic devices, such as chips, mounted on a
substrate, are protected by a cap sealed to the substrate by means of
a thermosetting adhesive. Currently, the adhesive is applied onto one
of the parts to be joined (cap or substrate) and the other part is
set in place. A sealed assembly is thereby obtained, but the adhesive
has not set yet. In order to cause the adhesive to set faster, the
assembly is heated. However, the gas pressure within the package
increases and causes localized breakages of the adhesive before the
latter sets completely, thereby creating defects in the seal.

      The proposed process overcomes such drawbacks in the following
steps:
      - Applying the adhesive onto one part.
      - Partially curing the adhesive at a temperature T during a
time t. Curing rate should be low enough that the adhesive will
adhere to the other part, yet high enough to withstand the pressure
increase.
      - Joining the parts together.
      - Heating the assembly to complete the polymerization of the
adhesive.

      This time the partially set adhesive will withstand the
increase in gas pressure, whereby an hermetic seal of adhesive is
obtained.