Radiation chemistry by soft X-ray spectromicroscopy.

摘要

This thesis presents the qualitative and quantitative determination of soft X-ray damage to selected polymer materials, including poly(methyl methacrylate) (PMMA), polyacrylonitrile (PAN), poly(ethyl cyanoacrylate) (PECA), poly(propylene carbonate) (PPC), poly(ethylene carbonate) (PEC), polyethylene terephthalate (PET), polystyrene (PS), and fibrinogen (Fg) by a scanning transmission X-ray microscope (STXM), and by a X-ray photoemission electron microscope (X-PEEM) for PMMA, PS and Fg. NEXAFS spectroscopy at C 1s, N 1s and O 1s edges was used to study the radiation chemistry of these polymers. The damage rate in terms of the critical dose is determined by the quantitative methodology developed in this thesis. The results show that not only radiation chemistry, but also damage rate is rather different among these polymers.;Chemically selective soft X-ray damage and patterning by STXM was explored and investigated in six different polymer systems: a PMMA/PAN bilayer film, a PMMA-blend-PAN micro phase-separated film, a poly(MMA- co-AN) copolymer film, a PECA homopolymer film, and two trilayer films, i.e. PMMA/PPC/PAN and PMMA/PEC/PAN. A high level of chemically selective damage was only achieved for layered polymer systems. Although the overall thickness of the bilayer and trilayer samples is much smaller than the damage spread range, the interface between the layers appears to very effectively block the damage transfer from one layer to the other. Full color patterning with the best spatial resolution to date of ∼ 150nm was achieved. A simulation program was developed to predict the patterning results with semi-quantitative accuracy.