Polymer Chain Configurations in Constrained Geometries: Ultrathin Films for Microlithography
Abstract
Ultrathin (0.9 -15.3 nm) poly(methyl methacrylate) (PMMA) films prepared by the Langmuir-Blodgett (LB) technique have been explored as high resolution electron beam resists. One eighth micron lines-and-spaces patterns have been achieved by using a Perkin Elmer MEBES I pattern generation system as the exposure tool. The etch resistance of films with thicknesses greater than 4. 5 nm is sufficient to allow patterning of chromium film suitable for photomask fabrication. Monolayer PMMA films containing 5 mol% pyrenedodecanoic acid (PDA) as a probe were prepared by transfer to the substrate at different surface pressures and characterized by fluorescence spectroscopy. The ratio of excimer to monomer emission intensity has a maximum value at 10 dyn/cm, which may be related to a structural rearrangement in the film. Intrinsic bilayer PMMA films prepared at 1 and 19 dyn/cm have also been examined by transmission electron microscopy. The wrinkle-like surface topography observed in the 19 dyn/cm sample and not in the 1 dyn/cm sample suggests that the structure in the LB PMMA film depends upon the transfer pressure. Polymethyl methacrylate.
Document Details
- Document Type
- Technical Report
- Publication Date
- May 30, 1989
- Accession Number
- ADA208692
Entities
People
- C. W. Frank
- P. S. Martin
- Roger Fabian W. Pease
- S. W. Kuan
Organizations
- Stanford University