We found positive pattern formation by ionic bonded photo-sensitive polyimide (PSPI). The PSPI is composed of poly(amic acid), photo-reactive tertiary amine (such as N.N-dimethylaminoethylacrylate), and photo-initiator. The PSPI basically has negative photo-sensitivity. However, we found that positive pattern formation from the PSPI when adding a post-exposure bake (PEB) about 120-140 °C. By adding PEB, imidization rate of unexposure area of PSPI is higher than that of exposed area. High imidizaiton of unexposed area of PSPI makes hard to solubule to alkaline solution. The imidization rate difference attributes to glass transition temperature difference between exposed area and unexposed area.

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A polyimidepolysiloxane was synthesized from 2,3,3',4'-biphenyltetracarboxylic acid dianhydride, 5,5'-methylene-bis(antranilic acid) and (,(-bis(3-aminopropyl)polydimethylsiloxane. It was used for a heat-curable solder resist having flame retardancy without flame retardant agent such as halogenated compounds. Addition of talc to the composition was effective for increasing flame retardancy. The developed solder resist achieved level 0 in UL94V test in TCP-type layered product. It had excellent flexibility and insulation reliability under a high-temperature and high-humidity environment.

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Polyimides were prepared from 4,4'-(hexafluoropropylidene)-diphthalic anhydride (6FDA), N,N-bis(3-aminopropyl)-methylamine (BAPMA) and 4,4'-dimamino-diphenyl ether (ODA) by one-pot method. The tertiary amine of BAPMA moiety was reacted with large excess of ethyl bromide at 70 °C for 10 h completely to convert to the quaternary ammonium salt. Surface-resistance-type humidity sensors were prepared by dip-coating solutions of polyimides bearing quaternary ammonium salt groups onto comb-shaped gold electrodes on ceramic substrates. The humidity sensor based on NTDA-BAPMA/ODA(2/1) in quaternary ammonium salt form displayed reasonably high sensitivity to relative humidity and a small hysterisis between humidification and dehumidification runs.

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The effects of the structural isomerism and the alkyl side-chain lengths in the precursors of BPDA/PDA polyimide (PI) on the temperature dependence of the refractive indices (i.e. thermo-optical coefficients) have been investigated. The PIs were formed on Si substrates by thermal curing of a) poly(amic acid)s (PAA) derived from three isomers (s-, a-, and i-) of biphenyltetracarboxylic acid dianhydride (BPDA) and p-di-minobenzene (PDA) and b) poly(amide alkylester)s (PAEs) having methyl-, n-propyl-, n-pentyl-, and n-octyl side chains. The TO coefficients of PIs increase as the average refractive indices and thermal expansion coefficients increase, which can be well explained with the derivative form of the Lorentz-Lorenz formula. The absolute values of TO coefficients for s-BPDA/PDA are smaller than those expected from their refractive indices, which is due to the dense molecular packing and the small coefficient of thermal expansion. Significantly larger TO coefficients were observed for the PI films prepared from PAEs than that from PAA, indicating that the larger volatile components (alcohols) eliminated during thermal imidization cause loose molecular packing in the former PIs. The use of structural isomers and chemical modification of precursors are effective to control the TO coefficients and their anisotropies in BPDA/PDA films.

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A hydroxyamide-containing tetracarboxylic dianhydride was synthesized from trimellitic anhydride chloride and bis(3-amino-4-hydroxyphenyl)sulfone. Poly(amic acid)s (PAAs) were prepared from this dianhydride with several diamines in N-methyl-2-pyrrolidone (NMP). The reflux of the PAA solutions at 160°C for 3 h allowed to form hydroxyamide-containing polyimides (PHAIs) highly soluble in common organic solvents such as NMP. The PHAI films could be completely converted to poly(benzoxazole imide)s (PBOIs) through cyclodehydration of the hydroxyamide groups upon heat treatment at 300°C. The thermally cured PBOI films showed a high Tg ranging 298-323°C. Other PBOI film properties are also discussed in this paper. The PHAI films were highly transparent at 435 nm but not at 365 nm. This is a problem to be solved for high sensitivity patterning at i-line. The solubility of the PHAI films in TMAH could be controlled by copolymerization using different diamines. The PHAI copolymer films dispersing diazonaphthoquinone (DNQ) as a photosensitizer were uv-irradiated through a photo-mask. Development using a 2.38 wt% TMAH aqueous solution containing 2-propanol gave a fine positive-type pattern with L&S = 20 μm.

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A negative-type photosensitive polyimide (PSPI) based on a semi-alicyclic poly(amic acid) (PAA) and a photobase generator (PBG), {[(4,5-dimethoxy-2-nitrobenzyl)oxy]carbonyl}2,6-dimethyl piperidine (DNCDP) has been developed. PAA was readily prepared from cyclobutane-1,2,3,4-tetracarboxylic dianhydride (CBDA) and 4,4'-oxydianiline (ODA) in N,N-dimethylacetamide (DMAc) at room temperature, and used directly by the addition of the PBG for photo-lithography. The PSPI consisting of PAA (85 wt%) and PBG (15 wt%) showed the high sensitivity of 53 mJ/cm² and contrast of 39.5, respectively, after exposed to 365 nm UV light (i-line) and developed with 0.238 wt% tetetramethylammonium hydroxide aqueous solution (TMAHaq) as a base-developer. A fine negative pattern with 6 μ features on a silicon wafer was obtained by a contact-printing mode and converted into a PI pattern by heating at 200 °C.

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Poly(tetrafluoroethylene) (PTFE) plates grafted with N-isopropylacrylamide (NIPAAm) as a thermosensitive monomer have been prepared by the combined use of the plasma treatment and photografting. In addition to the surface compositions of the grafted PTFE plates analyzed by ESCA and thermosensitive properties observed by contact angle measurements and the ellipsometry, -CONH groups attributed to PNIPAAm and even grafted layers of PNIPAAm prepared on plasma-treated PTFE plates are confirmed by an IR-ER method and by SEM, respectively.

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A 2-MHz generator was used for plasma treatment and plasma polymerization and compared with 13.56-MHz plasma. Without a matching unit, the 2-MHz generator can match the impedance by adjusting its frequency to create stable plasma, which is called "self-oscillation". Unlike the ordinary rf generator, as another advantage, the 2-MHz generator showed little radio-wave interference. In the O₂ plasma treatment of HDPE and PP plates, the surfaces became hydrophilic for both the frequencies, in which 2 MHz showed superior treatment effect to 13.56 MHz. In the plasma polymerization of CHF₃ and C₂H₄, the deposition rate in 2-MHz plasma was lower than that in 13.56 MHz. However, the properties of the deposited films were alike.

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We have developed a new fabrication method for on-demand microplasma-polymerized styrene film (MPPSF). The synthesis can be achieved on any substrate under atmospheric pressure using a laboratory-made torch-type microplasma polymerization apparatus. The fabrication conditions of MPPSF upon silicon wafers using localized patterning was investigated using a scanning atmospheric-pressure microplasma jet machine with automatic motion controller. We found that the dominant parameters were nozzle height from substrate, helium gas flow rate, and the scanning speed of the substrate holder. These were optimized to clarify the fundamental characteristics of scanning microplasma processing. Maskless pattern coating according to the CAD data has been successfully carried out using a prototype of the scanning microplasma jet coating system (SMPJCS). We have demonstrated line art painting of triangle, rectangle, and star patterns with flat coating of the local area, and typeface coating using the characters "AIST" to show its potential as a rapid microfabrication tool for on-demand functional MPP-films on any substrates synthesized by an automatic motion controller.

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The surfaces of medical materials are coated with polymer molecules or drugs in order to functionalize the surfaces in such ways as imparting biocompatibility. But in the case of inorganic materials there is the problem that polymers will have poor adhesiveness and be liable to peel. A coronary artery stent holds the vessel lumen patent by being expanded to the plastic deformation region, and if the material surfaces are coated with DLC, the coating must follow the plastic deformation of the base material. Accordingly we created a thickness-wise concentration gradient in the Si content that is added to the DLC, and discovered that thereby a DLC nanocoating is produced that does not crack under the plastic deformation required in a stent, and that has superior adhesion. In this way we succeeded in improving adhesion of the drug coating when used in combination with thin film material obtained via application of plasma surface treatment techniques, and in producing a practical stent that exhibits high biocompatibility even after slow release of the antithrombotic agent into the body is complete.

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We have developed a polymer film by plasma polymerizing MnTPPCl and characterized it by various optical and electrical methods and studied its application as a chemical sensor to detect H₂O₂ and as a bio-sensor to detect glucose. For characterization of the plasma polymer we have used UV-Vis spectroscopy, IR, SEM, AFM, ESCA and cyclic voltammetry. Plasma polymerized MnTPPCl was found to be a promising candidate in the field of bio and chemical sensors.

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As a material for fabricating biomicrosystem devices called lab-on-a-chip or micro total analysis system (μTAS), poly(dimethylsiloxane) (PDMS) has been widely used. Generally, the devices used in biological applications require some surface modification in order to control the hydrophilicity and nonspecific adsorption of biomolecules on their surfaces. However, it is difficult to achieve surface modification that remains sufficiently stable over long enough duration for use in PDMS microfluidic devices. In this paper, we report a simple but reliable method of applying a surface coating of biomimetic polymer to PDMS surfaces by the combinative use of photochemical surface oxidation by VUV irradiation and subsequent coating of phospholipid copolymer containing 2-methacryloyloxyethyl phosphorylcholine (MPC) and 3-methacryloxytriethoxysilane (METESi). The effectiveness of this coating process has been demonstrated by a significant reduction in the nonspecific adsorption of serum albumin and the formation of a micropatterned surface coating using a photomask.

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The aim of our study is to develop wearable environmental gas sensing system using surface transverse wave (STW) sensor device coated with microplasma-polymerized (MPP) films as gas molecular recognition compornents of STW gas sensor. In this paper, STW devices coated with styrene films using the microplasma-polymerization technique under atmospheric pressure were evaluated the gas sorption propertiy for water vapor and ethanol, respectively.

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We show an attempt of analyzing the distributions of transition moments of fluorophores in thin films. At a certain excitation wavelength, fluorophores can be excited with polarized light of different transition probabilities which are dependent on the direction of the transition moment. We compared emission bands of some pyridine-containing polymer films with varying the polarization angle of the polarizer and/or analyzer. The polarization angle dependence of these emission bands appeared to be different for different types of emission bands, and the distributions of the transition moments were discussed.

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In order to study photoinitiating mechanism of photochemically initiated radical polymerization in thick negative photoresist, fluorescence lifetime analyses of dry film photoresist were conducted by gallium nitride semiconducter laser pumped single-photon counting method. Lifetimes of photosensitizers, 4-methyl-7-(N,N-diethyl)aminocoumarin (C1), 4,4'-(N,N,N',N'-tetraethy)aminobenzophenon (EAB), 1-phenyl -3-[2-(4''-t-butylphenyl)vinyl]-5-(4'''-t-butyl) phenylpyrazoline (Pyraz) or 9,10-di-n-butoxyanthracene in film resists with and without photoinitiator, 2,2'-bis (σ-methylphenyl)-4,4',5,5'-tetraphenyl- imidazole (Me-HABI), as a quencher were successfully obtained. Quenching efficiencies, η, defined as 1-(τ/τ₀), were compared with photoinitiaing efficiencies which were obtained by RT-FTIR measurement of double bond disappearance and photospeed determined by gray scale step method. From correlation between quenching efficiencies and photoinitiating efficiencies in an extent, it was elucidated that the singlet excited state of photosensitizer seems to involve in the photoinitiation process as an important process.

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The binary hologram master with two-layer refractive index was developed and evaluated of their characteristics. The chirped diffraction grating was fabricating by electron-beam lithography. The grating structure has a one-dimensional grating with a period of 0.26 μm. The polarization separation lenses consist of two-layer, substrate materials and coated on thin-film materials. Example designs are presented, and the conventional diffraction analysis is used to evaluate the performance of these gratings. As an example, measurement of two-layer film is carried out and excellent confirmation is obtained.

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The permanent photoresist is a versatile material to fabricate three-dimensional structures for the Micro Electro Mechanical Systems (MEMS) field. The replacement to non-antimonite initiators is ongoing toward the mass manufacturing. We investigate on the reaction mechanism of cross-linking formulating chemically amplified negative-tone photoresists by adopting an infrared spectra measurement system. The consumption of epoxy group is monitored during post exposure bake (PEB). The patterning profile of 40 μm lines with 30 μm thickness indicates no significant difference on the photoresist formulation. However, the FT-IR measurement results and the simulation models describe the difference in cross-linking behavior in tested photoresists. The activation energy of cross-linking reaction is also calculated. The impact on cross-linking reaction from the residual solvent in photoresist film is also discussed utilizing a Thermal Desorption Spectrometer (TDS).

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We investigated the electroless and electrolytic plating of photopolymerized resin for use in the molding of three-dimensional nickel micro-structures. The micro-molding process consists of four steps: fabrication of the resin mold, electroless plating of the mold, electrolytic grinding to open the interior structure, and extraction. An epoxy resin mold, which is suitable for two-photon micro-polymerization, was successfully plated with nickel through this electroless process. Electrolytic plating was found to be useful for applying a thick nickel film on non-conductive resin with low crystal lattice distortion and few impurities. Regarding the design of the mold opening, it was shown that electroless plating does not proceed inside non-through-holes on the sub-millimeter scale, but that it proceeds inside through-holes with a diameter of 550 μm and down to the depth of 2 mm.

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Influence of photosensitizer on two-photon initiated polymerization (TPIP) of epoxide resin have been investigated. The three-dimensional (3D) micro-structures were fabricated to estimate rate of cationic polymerization by using TPIP. The line width and thickness of 3D micro-structures were measured as a function of laser-pulse energy, irradiation wavelength, and scanning speed to elucidate the rate of polymerization (Rp). It was demonstrated that volume of 3D micro-structures depends on the square of input intensity and proportional to two-photon absorption cross section and irradiation time of laser. Rp strongly depends on the quantum yield of H⁺ rather than efficiency of electron transfer from photosensitizer to initiator. Experimental results were compared with an original mathematical model.

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Inclusion compound formation of polyethylene glycol (PEG) with p-substituted benzene diazo compounds (SBD) in aqueous solutions was decided from activation energy (Ea) of thermal decomposition, dissociation constant Kd by Lineweaver-Burk plot modified with Michaelis-Menten formula and degradation temperature Dt, and compared with constitution of complex by WinMOPAC calculation. Thermal decomposition rate of p-chlorobenzene diazo compound (ClBD) with PEG was accelerated as with βcyclodextrine (CD) which include the benzene ring of the diazo compound. Kd of ClBD with PEG was larger than that with CD. PEG is not a ring, but a linear molecule. Dt of SBD with PEG in solid was higher than that without PEG300. Effect of molecular weight of PEG for Dt was, in a decreasing order, no additives - PEG300 < PEG600 < PEG1000 - PEG2000. Thermal decomposition of a diphenylamine-4-diazonium sulfate salt/formaldehyde condensate (DSR) / Polyvinyl alcohol (PVA) resist with PEG was accelerated. Photo decomposition of DSR/PVA resist with PEG 300 and 600 was also accelerated. Benzene diazo compound with PEG 300 was more stable than neat BD from by WinMOPAC caluculation.

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