Browse Prior Art Database

Focussed Infrared Reflow for TAB Attachment

IP.com Disclosure Number: IPCOM000108638D
Original Publication Date: 1992-Jun-01
Included in the Prior Art Database: 2005-Mar-22
Document File: 3 page(s) / 74K

Publishing Venue

IBM

Related People

Hicks, CA: AUTHOR [+2]

Abstract

Disclosed is a tool/process for reflowing fine lead pitch TAB (tape automated bonded) components onto glass epoxy FR4 cards. A focussed infrared lamp is used as a heat source, and a shield is used to direct the infrared energy to the outer lead area to be bonded.

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Focussed Infrared Reflow for TAB Attachment

       Disclosed is a tool/process for reflowing fine lead pitch
TAB (tape automated bonded) components onto glass epoxy FR4 cards.  A
focussed infrared lamp is used as a heat source, and a shield is used
to direct the infrared energy to the outer lead area to be bonded.

      The bonder, shown in the figures, consists of the following
elements:  the infrared lamp, mask, lead flattener and inert cover
gas delivery.

      The focussed infrared lamp provides up to 2000 watts of energy
distributed over a spectrum ranging from 600 to 2000 nanometers with
a maximum temperature of 1300~C.  The infrared lamp can quickly apply
heat to the TAB device, i.e., 0.5 second from room temperature to 99%
full power.  The amount of power applied and the dwell time are
optimized for rapid reflow without damage to the circuit card.

      The mask shields the component and the circuit card from the
radiant energy, thereby directing the heat to the lead frame and
pads.  The mask material is reflective to the lamp's infrared
spectrum.  Polished aluminum or a gold-plated surface finish can be
utilized for mask materials.

      The lead flattener enhances contact between the two surfaces to
be bonded.  A material with low absorbency over the lamp's operating
spectra was chosen, i.e., fused quartz, thus transmitting most of the
energy to the bonding surfaces.  Fused quartz has low absorbency,
high temperature resistance, an...