Browse Prior Art Database

Magnification Correction for X-Ray Mask Substrates

IP.com Disclosure Number: IPCOM000101387D
Original Publication Date: 1990-Aug-01
Included in the Prior Art Database: 2005-Mar-16
Document File: 2 page(s) / 80K

Publishing Venue

IBM

Related People

Maldonado, JR: AUTHOR [+2]

Abstract

This disclosure describes a general method to change the dimensions of an X-ray lithography mask. The method provides better registration between mask and wafer during X-ray lithography.

This text was extracted from an ASCII text file.
This is the abbreviated version, containing approximately 52% of the total text.

Magnification Correction for X-Ray Mask Substrates

       This disclosure describes a general method to change the
dimensions of an X-ray lithography mask.  The method provides better
registration between mask and wafer during X-ray lithography.

      During semiconductor device manufacturing, process-induced
wafer magnification errors may give rise to misregistration between
lithographic levels (mask and wafer). In order to control the mask
dimensions, and hence to achieve mask to wafer registration, thin
films deposited on the X-ray mask substrates have been proposed.  In
particular, piezoelectric films were proposed to change the mask
dimensions by means of applied electric fields.

      The purpose of this disclosure is to propose a general method
for magnification correction in X-ray masks.  The principle of
operation is based on the change of stress that takes place on a thin
membrane when a thin film under stress is deposited on some area of
the mem brane.   The method consists in changing the dimensions of
the mask substrate by depositing correcting thin films around the
periphery of the membrane.  The state of stress of the correcting
films may be changed by external means (electric or magnetic fields,
light, heat, etc.) depending on the material properties of the
correcting layer.  In other words, electric fields may be applied to
piezoelectric materials; magnetic fields to electrostrictive
materials; light and heat to photoelastic or thermoplastic materials,
respectively.  Fig. 1 shows a one-dimensional spring model for the
case of two correcting thin films deposited on each side of the X-ray
mask membrane adjacent to the...