Dismiss
InnovationQ will be updated on Sunday, Oct. 22, from 10am ET - noon. You may experience brief service interruptions during that time.
Browse Prior Art Database

Use of Penumbra to Control Feature Geometry

IP.com Disclosure Number: IPCOM000100197D
Original Publication Date: 1990-Mar-01
Included in the Prior Art Database: 2005-Mar-15
Document File: 2 page(s) / 52K

Publishing Venue

IBM

Related People

Poley, NM: AUTHOR

Abstract

In applications that require large area photolithography (e.g., flat panel displays), inherent errors are the result of misregistration and artwork runout. The method commonly used to minimize these effects is to use multiple exposures of a smaller section of the image to create a large array. This step and repeat method is inherently slow due to the multiple exposure and alignments required. The method described in this disclosure provides a lesser degree of dynamic correction using a scanner light source exposure system that is also applicable in a proximity printing mode.

This text was extracted from an ASCII text file.
This is the abbreviated version, containing approximately 78% of the total text.

Use of Penumbra to Control Feature Geometry

       In applications that require large area photolithography
(e.g., flat panel displays), inherent errors are the result of
misregistration and artwork runout.  The method commonly used to
minimize these effects is to use multiple exposures of a smaller
section of the image to create a large array. This step and repeat
method is inherently slow due to the multiple exposure and alignments
required.  The method described in this disclosure provides a lesser
degree of dynamic correction using a scanner light source exposure
system that is also applicable in a proximity printing mode.

      Common photolithographic processes allow the artwork mask to be
in contact with the photoresist, as shown in the figure.  The
thickness of the mask pattern (chromium or emulsion) is minimized to
reduce diffraction and penumbra effects and relieves the need for a
collimated light source.

      In this disclosure, which is directed toward multilayers of
orthogonal features, the effect of penumbra will be used to
advantage.  This effect is shown in the figure.  If the thickness of
the artwork is increased considerably, the penumbra effect is
pronounced and can be manipulated by rotation of a collimated light
source.  This rotation can be in any desired direction, and as the
errors normally encountered are periodic, the light source rotation
can be programmed to provide the desired compensation.

      An example of this is...