The concept of Main Chain Scission of photoresist polymers (MCS) is used to reducing the influence of molecular dimensions on the quality of photoresist patterns. Independent from the wavelength or lithography technique, the concept will raise in relevance as critical dimensions approach molecular dimensions. After the introduction of the MCS concept on last years conference of photopolymer science and technology, initial results are given in this paper to verify this concept.[1] Starting with polymer synthesis, after optimization of resist formulation and process conditions, ebeam patterns with the MCS resist and a commercial ebeam resist were generated. The patterns were compared with respect to their roughness. It was found, that lines printed in the MCS resist show a significant lower LER than the same patterns in the ebeam resist.

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Surface growth lithography is an attractive technique that eliminates the need for resist transparency. Critical to the success of this method is a smooth and homogeneous film capable of immobilizing a high concentration of initiator on the surface. This report outlines the design, synthesis, and preliminary testing of a polymeric photoactive acid generator (PAG), which is suitable for use with cationic surface growth lithography.

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We present the synthesis and screening of a series of new fluorinated materials designed to act as chemically amplified dissolution inhibitors for 157 nm lithography. Dissolution rates measured using a quartz crystal microbalance apparatus on a variety of matrix polymers as well as initial results demonstrating the imageability of this multi-component system are described.

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We developed conventional measurement method of film resistance of plasma-polymerized (pp-) films from styrene and allylalcohol as a monomer coated with stainless plates using a high-resistance meter. This determination method is estimated for the film resistance range from 10⁵ to 10¹² Ω/cm. We found correlation between film thickness from 150 to 500 nm and the resistance value of 10⁵ to 10¹² Ω /cm for pp-allylalcohol film.

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The enzyme activity of lipase, which was covalently immobilized directly or via the spacers (6-AA or HMDA) onto the ePTFE-g-PHEMA films prepared by the combined use of oxygen plasma pretreatment and photografting, was evaluated. The surfaces of ePTFE-g-PHEMA and ungrafted ePTFE films were observed by SEM. Grafted PHEMA chains penetrated into the inside of the membrane with an increase in the grafted amount. Although the optimal pH and temperature of immobilized lipase were the same as those of native lipase, the tolerance to pH persisted in the more wide range. The enzyme activity of immobilized lipase decreased with an increase in the amount of immobilized lipase and immobilization time. About 80% of the initial activity of the immobilized lipase was held even after the immobilized lipase was repeatedly used five times. However, the enzyme activity in prolonged preservation, e.g., more than 30 days, fell significantly.

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Electron emission phenomena from PVDF (polyvinylidene fluoride) ferroelectric substance by polarization inversion were studied. However the electron emission was not observed. To discussion the reason, the electric field distribution on the substance was theoretically calculated using a charge simulation method. The field was distributed along the surface of ferroelectric substance between the teeth electrodes. It was supposed that the high surface insulating properties prevented electron flow and accumulation on the surface. Therefore C-Au-S layer was tried to use as semiconducting layer on PVDF surface to accumulate the electric charge. The ability of C-Au-S layer on the ferroelectric electron emitter was discussed.

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This paper describes the chemical and morphological properties of super water-repellent surface of solid materials prepared by a 13.56 MHz inductively coupled plasma using fluorohydrocarbons such as vinylidene fluoride and 1, 1, 1, 2-tetrafluoroethane. Through the reaction initiated by the electron impact into fluorohydrocarbon molecules, fluorine-containing and hydrophobic polymers grew in the gas phase to deposit on substrates. The morphology of deposits seems to depend on hydrophilicity or hydrophobicity of substrates. The more hydrophilic substrate may maintain the smaller granular structure than ca. 100-nm diam. However, polymer granules may be expanded radially by surface tension and get into flat on hydrophobic substrates. Dynamic plasma CVD we proposed enabled us to control the size of deposited granules on the surface to be smaller and improve the fluorine content to be richer. Thus, we could easily obtain super water-repellent thin film with gradation in granular size and chemical compositions.

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The conditions and effects of various plasmas after passing through narrow slits have been investigated. It is important to know them in order to improve solid materials of complex structure. We have studied them, using a sample which simply represents the complex solid materials. This sample consists of slit plates, spacers and a base plate. Modification sources, which modify the material, were introduced into the sample through the slit plates. The conditions and effects of various plasmas were estimated by measuring the change between the contact angles before the plasma improvement and those after the plasma improvement. The material was treated in oxygen plasma, argon plasma and nitrogen plasma mainly. These kinds of plasma were generated by a discharge reactor of induction (coil) type. It has been found that these plasma gases can pass through a very complex route with twists and turns and treat a part behind the material. However, the processing effect is different with every plasma. Oxygen plasma’s effect was the strongest of the gases that we used. Argon plasma’s effect was not very strong in the condition of our experiment. In case of nitrogen plasma, its effect became low rapidly near the slits.

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Silk films were treated with O₂ and NH₃ plasmas for the improvement of dyeability. After O₂ and NH₃ plasma treatment of silk films, chemical composition of O and N on the surface increased, respectively. Also the concentration of acid and base functional groups increased. The silk films were insolubilized so that they could be dyed in an aqueous dye solution. The insolubilization affected the plasma-treatment effect in many surface properties. However, the color deepness of dyed silk film insolubilized after plasma treatment was greater than that of dyed film that plasma treated after insolubilization.

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We synthesized a series of i- and g-line sensitive non-ionic photoacid generators (PAGs). Photolysis and catalytic properties of the PAGs were examined. Photoreactivity of the PAGs was evaluated using UV-vis spectroscopy. The PAGs were used for photocrosslinking of epoxy-based polymers. The PAGs were also applied to positive-type photoresist materials. Sensitivity profile of the photoresists containing PAGs was affected not only by the photosensitivity of PAGs but also by the acidity of the generated acid. Post-exposure delay of the photoresists was dependent on the molecular size of the generated acid.

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Reactions in solid state polymers are different from those in solutions because the mobility of the polymer molecules is so restricted that reactivities vary with the local environment of site by site. One of the influencing factors on their reactivity is the free volume in polymers. In this paper, free volume effect on the photo-induced molecular orientation reaction of azobenzene derivatives in poly(methyl methacrylate) (PMMA) was described and the distribution of the kinetic parameters is discussed in terms of the free volume distribution in PMMA.

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Under visible light irradiation at 435.8 nm, gaseous ternary mixtures of glyoxal (GLY), carbon disulfide (CS₂), and allyltrimethylsilane (ATMeSi) and of GLY, acrolein (AC), and ATMeSi produced sedimentary aerosol particles. From the analysis of FT-IR spectrum measured with the sedimentary particles, ATMeSi was found to be incorporated into the sedimentary aerosol particles. The product yield increased with increasing partial pressure of GLY and ATMeSi, indicating that excited GLY molecules induced chemical reactions of ATMeSi as well as CS₂ and AC. Chemical reactivity of ATMeSi towards excited CS₂ was further investigated under UV light irradiation at 313 nm. A gaseous binary mixture of CS₂ and ATMeSi produced sedimentary aerosol particles which involved ATMeSi as the major chemical component, showing that ATMeSi was highly reactive towards excited CS₂ and chemical reactions between ATMeSi themselves were induced to form sedimentary aerosol particles.

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This paper describes recent progress in the designing of photoinitiator system for cationic or radical photopolymerization. In this regard, this paper focuses in particular on onium compounds such as iodonium and sulfonium. These compounds generate both acids and radicals upon the irradiation of light. Photoinitiator systems consisting of both onium compounds and several sensitizers are discussed.

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Photopolymerization efficiency of an acrylate formulation (Ebecryl 605) under light irradiation at 365 nm has been evaluated by using RTFTIR. The role of various multicomponent photoinitiating systems based on bis imidazole derivatives, in the presence or not of an aminobenzophenone, N-phenylglycine and several iodonium salt derivatives has been emphasized. Excited state processes in these two-, three- or four- component systems have been investigated through time resolved laser spectroscopy. The different photophysical processes and photochemical reactions involved are defined and the role of each partner is discussed : this helps to explain the high performance of the three- and four- component photoinitiating systems.

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In this document we propose an explanation of the different processes of photopolymerization through different experimentations. Simultaneously we will see different methods of investigation.

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Water-soluble UV inks, where encapsulated pigments were dispersed in photopolymers, were investigated by conventional materials design of UV hardening. The physical properties of the prepared ink were evaluated for application of the high accuracy dry on-demand printing (HADOP). A 25 μm stripe-pattern printing was achieved by the combination of the UV ink and the selection of a high resolution plate. The superior and sharp imaging was performed by HADOP. Color filters were obtained by the isolated lines with good reproducibility.

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