Browse Prior Art Database

Process for Formimg Contact Vias

IP.com Disclosure Number: IPCOM000115191D
Original Publication Date: 1995-Mar-01
Included in the Prior Art Database: 2005-Mar-30
Document File: 2 page(s) / 41K

Publishing Venue

IBM

Related People

Wenzel, D: AUTHOR

Abstract

Disclosed is a simplified process sequence for forming contact vias in a semiconductor structure.

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

Process for Formimg Contact Vias

      Disclosed is a simplified process sequence for forming contact
vias in a semiconductor structure.

      Figs. 1, 2a and 2b show a typical prior art process sequence.
In Fig. 1 the metal contact area 1 is covered by a passivation layer
2.  The desired via pattern has first been transferred to a photo
resist layer 3 by exposing and developing the resist and in a second
step to a polyimid layer 4 beneath the resist layer 3.  The photo
resist has to be hardened by thermal processes prior to or after
developping the resist.

      In Fig. 2a the passivation layer 2 is opened by reactive ion
etching and finally the resist is stripped as shown in Fig. 2b by
plasma strip, chemical wet etch or a combination thereof.

      Starting with Fig. 1, in a simplified process sequence the
structured photo resist 3 is removed by wet processes as shown in
Fig. 3a and then the passivation layer 2 is opened as indicated in
Fig. 3b in the same way as already shown in Fig. 2b.

      Following this process sequence the photo resist mask may
easily be removed from the polyimid layer since its surface had no
more to suffer from the chemical and mechanical changes induced by
the reactive ion etching.  A further advantage of this process
sequence is that hardening of the resist may be avoided.