Browse Prior Art Database

Thermode With Removable Patterned Surface

IP.com Disclosure Number: IPCOM000100566D
Original Publication Date: 1990-May-01
Included in the Prior Art Database: 2005-Mar-15
Document File: 1 page(s) / 40K

Publishing Venue

IBM

Related People

Bickford, HR: AUTHOR [+4]

Abstract

Disclosed is a thermode for use in tape automated bonding (TAB), which increases the flexibility of the manufacturing process.

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This is the abbreviated version, containing approximately 82% of the total text.

Thermode With Removable Patterned Surface

       Disclosed is a thermode for use in tape automated bonding
(TAB), which increases the flexibility of the manufacturing process.

      The thermodes generally used in TAB technology have flat planar
surfaces or ring geometries and are used to compress cantilevered
beam leads against integrated circuit I/O bonding structures to
affect interconnection of the chip to the next packaging level.  The
simplest TAB packages have I/Os arranged in one or two peripheral
rows around the chip and utilize lead frames with one metal layer.

      In more advanced TAB applications, the central chip area may
also be provided with I/O sites for additional signal or ground
lines, as well as, to support power distribution.  Such a
configuration may be termed area TAB. Consequently, the lead frame
may have multiple metal layers, which are not necessarily of the same
thickness, and polymer support structures that protrude between the
chip and the bonding thermode surfaces.  This, in turn, requires
customized thermodes that have recesses in the surface, possibly on
multiple levels, so that all leads are simultaneously pressed against
their bonding structures, regardless of lead thickness variations and
any intervening polymer structures of the lead frame.

      Inexpensive thermodes of this type may be fabricated in
quantity by lithographic patterning and etching of strips or sheets
of appropriate metal.  The thermodes take the...