Channel waveguides are produced from organic-inorganic hybrid materials derived by the sol-gel process. The organic-inorganic hybrid film containing photosensitive C=C bonds changes by the UV irradiation. The solubility difference between irradiated and unirradiated parts can easily give a core with about 8μm square. The refractive indexes of the core and cladding layers are measured and the single mode waveguide is designed for the materials.

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Zinc 9, 18, 27, 36-tetrakis(p-tolyl)tetrabenzoporphyrin (ZnTTBP) was synthesized, photophysical process was determined by absorption and fluorescence spectra, fluorescence lifetime measurements, and transient absorption measurements. ZnTTBP has absorption of Q-band at 620nm, Soret at 420nm, and the fluorescence emission and T-T absorption were observed at 630nm and 480nm, respectively. Sensitization to a photo acid generator (PAG) does not occur from one-photon excited S₁ or T₁ states, while irradiation of the mixture of ZnTTBP and the PAG by 635nm and 490nm light changes the absorption spectrum due to the generation of ZnTTBP cation. This result suggests electron transfer from ZnTTBP to PAG occurred. Isobutyl vinyl ether was polymerized by the acid generated via ZnTTBP sensitization.

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Novel diaryliodonium hexafluorophosphate salts (NDAI) as cationic photoinitiators were synthesized. The substituent groups of two aromatic rings were investigated to lower the toxicity and to improve the solubility of diaryliodonium salts. NDAIs were negative in the mutagenicity tests and soluble well in common organic solvents and representative cationic polymerizable resins. The photocuring ability of NDAI was evaluated by the real-time FT-IR measurement. NDAI exerted high photoactivity in the presence of appropriate photosensitizers, e.g. naphthalene derivatives, carbazole derivatives and anthracene derivatives. Especially, in the pigmented system containing titanium dioxide, the combination of NDAI and 2-ethyl-9, 10-dimethoxyanthracene showed higher photocuring ability than naphtyl-type sulfonium salt. The organic solvent resistance of cured film and the thick film curing were also examined. NDAIs are highly efficient cationic photopolymerization initiators having various features and possible to be employed in the wide applications.

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Structural effects of nitro-substituted amineimide derivatives on photobase generation were investigated by using an epoxide/thiol curing system. The absorption of amineimide derivatives was closely related to the position of a nitro group and the efficiency of photobase generation increased in the order of para>meta>ortho position. The molecular size of the amines generated from amineimide derivatives was found to affect the curing temperature of an epoxide/thiol curing system: The smaller the molecular size, the lower the curing temperature at higher concentration.

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An overview of the photoinitiators for use in electronic applications is given, including both, commercially available products as well as semi-commercial or developmental products. Areas to be covered are photoinitiators for PCB manufacturing and flat-panel displays production process and photoacid generatiors for use in semiconductor resists.

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Photochemical reaction in three different water-developable flexographic printing plates was characterized. The distribution of photochemical reaction in the direction of thickness was evaluated by utilizing ¹³C NMR and IR (ATR) measurements, and the results obtained showed that the distribution of reaction as well as the overall reaction in the printing plates depends on the plate compositions. ¹H NMR analysis for soxhlet extracts of exposed samples showed that the reactivity of monomers depends on its structure and molecular weight in relating to a specified phase condition of the composition.

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The adhesion of the PTFE substrate whose surface was modified by photochemical reaction upon the irradiation of an ArF excimer laser and Xe₂* excimer lamp under a hydrazine and ammonia atmosphere was examined by a peel-off test for the sample prepared by jointing the PTFE substrate and a copper plate through chemical adhesives. These surface-modified PTFE samples were improved in adhesive property, which was 7-20 times higher than that of original PTFE. The chemical modification on the surface of PTFE was discussed on the basis of XPS and static SIMS analyses.

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Polyperinaphthalene (PPN) thin films are prepared by excimer laser ablation (ELA) of a 3, 4, 9, 10-perylenetetracarboxylic dianhydride (PTCDA) target or a mixture target of PTCDA with Co or TiO₂ powder (PTCDA/X: X=Co, TiO₂) using XeCl excimer laser beams. Enhancement of elimination reaction of side groups of PTCDA is observed by ELA of PTCDA/Co and PTCDA/TiO₂. In particular, for PTCDA/TiO₂, the reaction occurs at a fluence of 0.25Jcm^-2pulse^-1much lower than the case of PTCDA/Co at room temperature. Heterojunctions of PPN films prepared by ELA of PTCDA with Si wafers are fabricated. Well rectifier property is obtained for the junction of the PPN with a n-Si substrate. Current versus voltage curves of the heterojunction in the dark and under illumination show that the junction is promisimg as a photovoltaic cell. Furthermore, PPN films are applied to anode electrodes for ultra thin rechargeable Li ion batteries. Substrate temperature dependence ofeffective capacitance of lithium ions at first cycle are investigated. In addition, in-situ Raman spectroscopy of the films under lithium ion doping and undoping is performed to elucidate the storage mechanism of lithium ion at cis-polyacetylene-type edge (phenanthrene-edge) of PPN structure.

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Under UV light irradiation at 313nm, a gaseous mixture of trimethylsilyl azide (TMSAz) and acrolein (AC) produced sedimentary aerosol particles with a mean diameter of 0.74μm. From the chemical analysis of the product by FT-IR spectroscopy, TMSAz was found to be incorporated into the sedimentary particles of polyacrolein by forming Si-O bond. Gas-phase chemical reaction between TMSAz and AC was observed in the dark, and was investigated from the analysis of volatile products by GC/MS and FT-IR spectra; as a final product, hexamethyldisiloxane was identified. High chemical reactivity of TMSAz towards AC was applied to modify the surface character of polyacrolein particles.

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Two-photon polymerization initiated by a tri molecular initiating system composed of 7-diethylamino-3-2(2′-benzimidazolyl)coumarin, Titanocene and N-phenylglycine was investigated, The photosensitizer has been proved to possed large two-photon absorption cross-section for 800nm femtosecond laser. sensitizer/coinitiator system has hight Photosensitivity for polymerization of photosensitive resin. The photopolymer system has been demonstrated for fabricating three-dimensional microstructure.

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In this paper, a new type photoactive compounds (PAC) of diazidonaphthoquinone(DNQ) have been synthesized based on the ballast of 2, 2-diphenyl-2-phenols group acetic lectone compound which is synthesized from benzilic acid.
The new type PACs have good miscibility with common novolacs and dissolubility in the solvents used in positive photoresists and photosensitive compositions for PS plates. The photosensitive compositions composed of each new PAC and the novolac have well film-forming performance. Before exposure, the formed photosensitive film behaves strong dissolution inhibiting effect in alkaline developer. After exposure it becomes very easy to dissolve in developer. In other words it obtains good dissolution accelerating performance in exposed areas. Because the change of the effect of dissolution inhibition and dissolution acceleration is remarkable, B/P value can be designed higher, the photosensitivity is also higher and the quantity of exposure energy required for imaging is about 200mJ/cm². In addition, it has good contrast and imaging film is easy to be taken off in concentrated alkaline liquor.
The PACs are widely used in photoresists for integrated circuit(IC), especially in photoresists for liquid crystal display(LCD) and photosensitive compositions for positive PS plates including heat-sensitive computer-to-plate(CTP) plates.

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We studied the mechanism of the photoreaction of benzilmonooxime methacrylate (BIMA) polymers, which are highly photosensitive materials, using stationary photoirradiation and laser flash photolysis (LFP) of the copolymer of methyl methacrylate with BIMA (3.6mol%). Since the Stern-Volmer relationship for the quenching of the main chain degradation was curved, the reaction proceeded through both excited singlet and triplet states. When the singlet contribution was assumed to be ca. 30% of the whole reaction, a linear relationship was obtained. In 266, 308 and 355nm LFP of the BIMA polymer, we could not detect any transient absorption bands. The triplet energy level of the polymer was estimated to be between 274 and 289kJ mol_-1 by means of sensitized reactions. To clarify the reaction mechanism, we carried out 266nm LFP of model compounds: benzilmonooxime phenylacetate (BIPA) and benzilmonooxime diphenylacetate (BIDA). In LFP of BIPA, a transient absorption band was measured at 310nm immediately afte r the flash. At 4μs after the flash, another new band was detected at 460nm. These bands were assigned to benzyl and benzoyl radicals, respectively. In LFP of BIDA, we measured new transient absorption at 340nm, which was assigned to diphenylmethyl radical.

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Novel photosensitive sol-gel materials, which are comprised of siloxane oligomers and a photo acid generator (PAG), have been developed. The spectroscopic studies led to the observation that sol-gel reaction was affected by a balance of between PAG and amine content added as catalysts. Additionally, the balance strongly influenced the line pattern profile formed with exposure, which indicated that the photolithographic properties changed from negative to positive tone with the amine content. An optical channel waveguide based on sol-gel materials was fabricated through photolithographic processing and showed low propagation losses that were 0.3dB/cm and 0.6dB/cm at 1.31μm and 1.55μm, respectively, in addition to excellent long-term reliability.

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Reactions in polymer solid are different from those in solutions because the mobility of polymer molecules is so restricted that reactivities vary in the local environment and site by site. One of the factors influencing on their reactivity is free volume of the polymer, however free volume has not been quantitatively estimated up to now. In this paper, azobenzene in polymethyl methacrylate was used as photochromic probe. Azobenzenein PMMA were isomerized with photoirradiation and the change in the absorption spectra of azobenzene was observed Quantum yield distribution for the photoreaction was obtained by analyzing the observed curve of isomerization, and the effect of annealing temperature on their quantum yield distribution is also described.

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By directly applying a load to top corner of a resist pattern with a microcantilever tip, a dot resist pattern adhering on a flat substrate can be collapsed easily by accompanied with slight residue. By the synchrotron radiation (SR) lithography, the dot resist patterns ranging from 84 to 364nm diameter and 550nm height are formed on the Si(100) substrate. The static load applied by the cantilever, which is required for pattern collapse, decreases with decreasing the pattern diameter and is proportional to the cross-sectional area of the resist pattern. In combination with the stress distribution analysis, the mechanism of pattern collapse and residue formation can be clarified. The pattern collapse occurs by the stress concentration at the pattern bottom slightly away from the interface. It is clear that the pattern collapse can be dominated by the stress concentration in the resist pattern.

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The peeling property of the resist pattern can be analyzed on the point of van der Waals (vdW) interaction between polymer aggregates and substrate by using the atomic force microscope (AFM). By treating the substrate with hexamethyl-disilazane (HMDS), the interaction length between tip and substrate is shorten and weakened. It is clarified that a part of polymer aggregates condensed at pattern bottom have no contribution to the interaction with the substrate because the interaction length becomes short. At the resist-substrate interface, a certain vacancy among the polymer aggregates is found out. Based on the aggregation model, it is clarified that exposing the substrate to HMDS vapor acts to weaken the peeling strength of the resist pattern.

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I-Line sensitive photoacid and photobase generators were prepared. Their use for photocrosslinking of the blended system of poly(vinylphenol) (PVP) and diepoxy fluorene derivatives was studied. Photolysis properties of the photoacid and photobase generators were investigated and the effect of photo-sensitizer on photolysis of the photoacid or photobase generators was discussed. PVP films containing diepoxy fluorene derivatives, photoacid or photobase generators, and photo-sensitizers were photocrosslinkable on irradiation at 366nm after the post-exposure-bake (PEB) treatment. Photocrosslinking properties were discussed in terms of the irradiation dose, PEB temperature, structure of diepoxides, photoacid or photobase generators and photo-sensitizers. Thermal properties of the photocrosslinked PVP/diepoxy fluorene blends were investigated.

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The photodimerization reaction of pendant styrylpyridinium (SbQ) groups in poly(vinyl alcohol), PVA, and poly(vinyl alcohol-b-acrylic acid) block copolymers, P(VA-b-AA), was evaluated by a spectrophotometric measure-ment. The thermal properties of polymer films were analyzed by evaluating the differential scanning calorimetiy (DSC) and the dynamic mechanical thermal analysis (DMA) curves.
The degree of dimerization of SbQ groups during the photoreaction was ultimately inclined to constant at about 0.7mol% SbQ in both P(VA-b-AA)-SbQ and PVA-SbQ films. The rate of cyclodimer formation of SbQ groups depended on the pH in casting solution of films. The rate in a P(VA-b-AA)-SbQ film was faster than that in a PVA-SbQ film. The number of cross-linked SbQ groups per polymer chain, Nc, deviate from linearity with increasing the degrees of polymerization of PVAs. The numbers of cross-linked SbQ groups per vinyl alcohol repeat unit, Nu, have the highest value for the polymer with degrees of polymerization of 2500. The P(VA-b-AA)-SbQ film has higher dynamic storage modulus than that of a PVA-SbQ film. The free volume fraction of the amorphous region in a P(VA-b-AA)-SbQ film has larger than that in a PVA-SbQ film. The Tm decreased slightly with increasing the degree of polymerization of the PVAs. The films having higher degree of polymerization exhibited lower crystallinity. The degree of crystallinity in the films after photoinadiation was lower than that in the films before photoirradiation.

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