Additive-Containing Rinses for LER and Defectivity Control During High-Resolution Resist Patterning

Published

October 12, 2021

Author(s)

D L. Goldfarb, S D. Burns, M Angelopolous, S Skordas, R L. Burns, M C. Lawson, C J. Brodsky, V Vishnu, E Jablonski, Vivek Prabhu, Ronald L. Jones, B D. Vogt, Christopher Soles, Eric K. Lin, Wen-Li Wu

Abstract

The addition of a surface conditioning agent to the de-ionized water rinse used to quench the photoresist development process is an attractive methodology that can afford a controlled decrease in resist line edge roughness (LER) or a reduction in defectivity levels, during lithographic patterning. The use of additive-containing rinses involves the interfacial adsorption of the surface-active material (e.g. ionic surfactants, neutral polymers, polyelectrolytes) and/or its penetration into the patterned resist structure, which can be held responsible for polymer chain relaxation and reorganization within the resist matrix, resulting in reduced LER. The non-specific adsorption process can also lead to the creation of repulsive (electrostatic or steric) forces between additive-coated surfaces, thus allowing for particulate stabilization in the rinse liquid and the minimization of defects. In this study, LER improvement (8 % to 16 %) induced by an organic salt and defectivity reduction (ca.= 100) created by a polyelectrolyte contained in the rinse liquid are demonstrated in 193 nm resist systems. Also, additive adsorption to a 193 nm resist surface is monitored using a quartz crystal microbalance (QCM), while the repulsive force created between additive-coated surfaces is detected using atomic force microscopy (AFM) and the presence of residual additive is quantified using total x-ray reflection fluorescence (TXRF), near edge x-ray absorption fine structure (NEXAFS) and contact angle measurements. The experimental evidence provided supports the proposed mechanisms leading to LER and defectivity improvement.

Citation

Journal of Microlithography Microfabrication and Microsystems

Pub Type

Journals

Keywords

adsorption, LER, line edge roughness, resist defetivity, rinse additive, surface conditioning, surfactants

Citation

Goldfarb, D. , Burns, S. , Angelopolous, M. , Skordas, S. , Burns, R. , Lawson, M. , Brodsky, C. , Vishnu, V. , Jablonski, E. , Prabhu, V. , Jones, R. , Vogt, B. , Soles, C. , Lin, E. and Wu, W. (2021), Additive-Containing Rinses for LER and Defectivity Control During High-Resolution Resist Patterning, Journal of Microlithography Microfabrication and Microsystems (Accessed January 17, 2025)