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Title: Stepper focus characterization using diffraction from latent images

Abstract

We present a novel technique for the rapid, nondestructive evaluation of the contrast of the latent image in photoresist. Measurements are made of the intensity of light diffracted from a grating pattern in exposed, undeveloped photoresist, the so-called latent image. Optimum exposure tool parameters such as exposure tool dose and focus can be determined based on the intensity of light diffracted into specific orders. Employing the proposed technique, measurements can be made sufficiently fast to allow rapid control of the exposure conditions, such as focus, which influences image contrast. The measurement can be made after an exposure, and corrections to focus for subsequent exposures may be derived to compensate for changing optical or mechanical properties of the wafer. The technique may be used with a variety of photoresist materials on different substrates. 19 refs., 24 figs.

Authors:
; ;  [1]
  1. Univ. of New Mexico, Albuquerque, NM (United States); and others
Publication Date:
OSTI Identifier:
161690
Report Number(s):
CONF-930115-
Journal ID: JVTBD9; ISSN 0734-211X; TRN: 95:004881-0006
Resource Type:
Journal Article
Journal Name:
Journal of Vacuum Science and Technology. B, Microelectronics Processing and Phenomena
Additional Journal Information:
Journal Volume: 11; Journal Issue: 4; Conference: 20. physics and chemistry of semiconductor interfaces, Williamsburg, VA (United States), 25-29 Jan 1993; Other Information: PBD: Jul-Aug 1993
Country of Publication:
United States
Language:
English
Subject:
42 ENGINEERING NOT INCLUDED IN OTHER CATEGORIES; LATENT IMAGES; EVALUATION; PHOTORESISTORS; FABRICATION; DIFFRACTION; SUBSTRATES; MEASURING METHODS; PROCESS CONTROL

Citation Formats

Milner, L M, Bishop, K P, and Naqvi, S H. Stepper focus characterization using diffraction from latent images. United States: N. p., 1993. Web. doi:10.1116/1.586926.
Milner, L M, Bishop, K P, & Naqvi, S H. Stepper focus characterization using diffraction from latent images. United States. https://doi.org/10.1116/1.586926
Milner, L M, Bishop, K P, and Naqvi, S H. 1993. "Stepper focus characterization using diffraction from latent images". United States. https://doi.org/10.1116/1.586926.
@article{osti_161690,
title = {Stepper focus characterization using diffraction from latent images},
author = {Milner, L M and Bishop, K P and Naqvi, S H},
abstractNote = {We present a novel technique for the rapid, nondestructive evaluation of the contrast of the latent image in photoresist. Measurements are made of the intensity of light diffracted from a grating pattern in exposed, undeveloped photoresist, the so-called latent image. Optimum exposure tool parameters such as exposure tool dose and focus can be determined based on the intensity of light diffracted into specific orders. Employing the proposed technique, measurements can be made sufficiently fast to allow rapid control of the exposure conditions, such as focus, which influences image contrast. The measurement can be made after an exposure, and corrections to focus for subsequent exposures may be derived to compensate for changing optical or mechanical properties of the wafer. The technique may be used with a variety of photoresist materials on different substrates. 19 refs., 24 figs.},
doi = {10.1116/1.586926},
url = {https://www.osti.gov/biblio/161690}, journal = {Journal of Vacuum Science and Technology. B, Microelectronics Processing and Phenomena},
number = 4,
volume = 11,
place = {United States},
year = {Thu Jul 01 00:00:00 EDT 1993},
month = {Thu Jul 01 00:00:00 EDT 1993}
}