Electron Beam Metrology of 193 nm Resists at Ultra Low Voltage

Published

May 1, 2003

Author(s)

N. Sullivan, Ronald G. Dixson, B Bunday, M Mastovich, P Knutruda, P Fabre, R Brandoma

Abstract

Resist slimming under electron beam exposure introduces significant measurement uncertainty in the metrology of 193 nm resists. Total critical dimension (CD) uncertainty of up to 10 nm can arise from line slimming through a combination of the line slimming during the initial measurement pass and the variation of line slimming across the wafer. For a 100 nm process, the entire CD error budget, can be consumed by line slimming. This research examines the expanded uncertainty that results from the use of offset techniques to account for resist slimming in the process control of 193 nm resist CDs. The uncertainty associated with such offset techniques can be as great as 10 nm, depending upon the 193 nm resist and landing energy evaluated. Data is presented to demonstrate that 193 nm resist CD features expreience line slimming greater than 5 nm, at 500 eV landing energy during the initial measurement pass, and further, that subsequent measurements demonstrate greatly reduced slimming and as a result are not indicative of the true magnitude of line slimming. Experiments were conducted, using CD-AFM pre and post analysis, studying the effect of ultra low landing energies, down to 95 eV, indicating that this significantly reduces the line slimming, down to 1 nm or less.

Proceedings Title

Proceedings of SPIE, Metrology, Inspection, and Process Control for Microlithography XVII, Daniel J. Herr, Editor

Volume

5038

Issue

Pt. 1

Conference Dates

February 24, 2003

Conference Location

Santa Clara, CA, USA

Conference Title

Materials-Related Metrology I

Pub Type

Conferences

Keywords

AFM, atomic force microscopy, critical dimension, metrology, resist, scanning electron microscopy, SEM uv lithography

Citation

Sullivan, N. , Dixson, R. , Bunday, B. , Mastovich, M. , Knutruda, P. , Fabre, P. and Brandoma, R. (2003), Electron Beam Metrology of 193 nm Resists at Ultra Low Voltage, Proceedings of SPIE, Metrology, Inspection, and Process Control for Microlithography XVII, Daniel J. Herr, Editor, Santa Clara, CA, USA (Accessed October 4, 2024)