Differential dissolution and electron-beam lithographic sensitivity of poly(methyl methacrylate). [Gamma radiation]

Journal Article · Wed Jun 01 00:00:00 EDT 1977 · Polym. Eng. Sci.; (United States)

OSTI ID:6167541

Helbert, J N ^[1]; Cook, Jr, C F; Poindexter, E H; Wagner, B E

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1. U.S. Army Electronics Tech. and Devices Lab., Fort Monmouth, NJ

Photolithographic and electron-beam integrated circuit fabrication techniques rely heavily upon differences in polymer resist dissolution (development) rates to produce circuit patterns. We have applied the wide-line NMR technique, augmented by dynamic nuclear polarization, to the measurement of polymer dissolution rates of poly(methyl methacrylate), (PMMA). At high gamma-ray exposures, we find PMMA to have dissolution rates from 2X to 1000X those of unirradiated material. The highest radiation-enhanced dissolution rates are obtained with carbon tetrachloride-based developer solutions, whereas generally lower enhanced rates are observed with 1:3 acetone or methylethylketone/isopropanol standard developer. E-beam line exposures are developed in PMMA and poly(ethyl methacrylate), PEMA, resists using similar developers for comparison. Using straight CCl/sub 4/ as a developer, e-beam lines 1-2..mu.. wide were developed in 3800 A thick PEMA resist at 1 x 10/sup -5/ C/cm/sup 2/ with less than or equal to 200 A loss in unexposed resist thickness. The higher differential dissolution with CCl/sub 4/, a poorer solvent for unirradiated PMMA than acetone or MEK, is explained by decline in polarity of PMMA by radiation-induced decarboxylation. 5 figures.

• OSTI ID: 6167541
• Journal Information: Polym. Eng. Sci.; (United States), Journal Name: Polym. Eng. Sci.; (United States) Vol. 17:6; ISSN PYESA
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
360406* -- Materials-- Polymers & Plastics-- Radiation Effects-- (-1987)
38 RADIATION CHEMISTRY, RADIOCHEMISTRY, AND NUCLEAR CHEMISTRY
400600 -- Radiation Chemistry
ACETONE
ALCOHOLS
BEAMS
CARBON TETRACHLORIDE
CHEMICAL RADIATION EFFECTS
CHEMICAL REACTIONS
CHEMISTRY
CHLORINATED ALIPHATIC HYDROCARBONS
COMPARATIVE EVALUATIONS
DECOMPOSITION
DEVELOPERS
DISPERSIONS
DISSOLUTION
ELECTROMAGNETIC RADIATION
ELECTRON BEAMS
ESTERS
GAMMA RADIATION
HALOGENATED ALIPHATIC HYDROCARBONS
HYDROXY COMPOUNDS
IONIZING RADIATIONS
KETONES
LEPTON BEAMS
MAGNETIC RESONANCE
MIXED SOLVENTS
MIXTURES
NUCLEAR MAGNETIC RESONANCE
NUCLEI
ORGANIC CHLORINE COMPOUNDS
ORGANIC COMPOUNDS
ORGANIC HALOGEN COMPOUNDS
ORGANIC POLYMERS
ORGANIC SOLVENTS
PARTICLE BEAMS
PMMA
POLARIZED NUCLEI
POLYACRYLATES
POLYMERS
POLYVINYLS
PROPANOLS
RADIATION CHEMISTRY
RADIATION EFFECTS
RADIATIONS
RADIOLYSIS
RESONANCE
SOLVENTS
TIME DEPENDENCE