Browse Prior Art Database

Metal Mask PCM Process

IP.com Disclosure Number: IPCOM000102074D
Original Publication Date: 1990-Oct-01
Included in the Prior Art Database: 2005-Mar-17
Document File: 2 page(s) / 61K

Publishing Venue

IBM

Related People

Lyons, CF: AUTHOR [+2]

Abstract

Disclosed is a lithographic process which extends the resolution capability of step-and-repeat projection, aligners or other patterning exposure systems, using standard resist materials and wafer processing techniques.

This text was extracted from an ASCII text file.
This is the abbreviated version, containing approximately 67% of the total text.

Metal Mask PCM Process

       Disclosed is a lithographic process which extends the
resolution capability of step-and-repeat projection, aligners or
other patterning exposure systems, using standard resist materials
and wafer processing techniques.

      The process is an extension of the current bilayer resist PCM
process which employs an imaging resist layer of the positive working
diazonaphthoquinone/novalak resin (DQN) type coated over a
planarizing resist comprising polydimethylglutarimide (PMGI).

      In the current process, the DQN resist is exposed and
developed.  The resulting pattern forms a mask in intimate contact
with the PMGI resist.  Subsequent blanket exposure and development
transfers the pattern into the PMGI layer.
      The disclosed process operates as follows:

      Extending the develop time of the DQN resist results in
isotropic etching of the PMGI layer.  The appropriate develop time
undercuts the image layer slightly and results in an ideal lift-off
stencil, which is then used to pattern a thin layer of vacuum
deposited metal or insulator on top of the PMGI.  With this metal or
insulator pattern acting as a mask the images can be transferred into
the PMGI layer using either oxygen reactive ion etching or blanket UV
exposure and wet development.  The best results are obtained with
oxygen RIE.  The process is shown schematically in the figure.

      Using this technique even badly degraded DQN images can be used
t...