Journal of Vacuum Science & Technology B Microelectronics and Nanometer Structures Processing Measurement and Phenomena · 1995 · 82 citations · 0 references
X-ray CrystallographyX-ray SpectroscopyEngineeringChemistryX RaysX-ray ImagingX-ray TechnologyRadiation OncologyRadiation ChemistryPolymer ChemistryHealth SciencesMaterials ScienceCarbon Absorption EdgeEdge Structure SpectroscopyPhysical ChemistryPolymer AnalysisPolymethyl MethacrylateSpectroscopyPolymer ScienceX-ray DiffractionChemical ChangesExposure Strategies
We have observed the chemical changes in PMMA irradiated by x rays in situ. The chemical changes are monitored by micro-x-ray absorption near edge structure spectra at the carbon absorption edge. The loss of the ester group (C=O) and formation of C=C bonds have been determined quantitatively from changes in the intensities of the respective π* resonant peaks as a function of dose. Samples prepared under different conditions were examined. From the dose dependence of bond formation, scission and linking, the performance of the resist can be predicted, so that the preparation strategy, dose, and development can be optimized.