The possibility of generating tailored surface characteristics (adhesion, biocompatibility, wettability, etc.) from plasma modified surfaces by derivatization and grafting reactions, opens up new possibilities for the creation of advanced materials. Implantation of reactive amine (primary amine) functionalities onto synthetic polymeric surfaces under cold plasma conditions- one of the potential approaches to surface functionalization has been the subject of numerous investigations of recent years. It has been shown that ammonia plasmas do not implant primary amine groups efficiently and consequently, a large number of amine-group containing compounds were tested as alternatives. However, the low volatilities of many of potential aminating agents limit considerably their plasma processing. In this contribution a novel approach of surface amination of PP samples from melamine and urea precoated surfaces is presented. ESCA, ATR-FTIR and ex-situ post plasma grafting reaction data indicate that simultaneous plasma induced evaporation, fragmentation and primary amine implantation processes can be successfully developed. The surface primary-amine concentrations were evaluated by chemical derivatization technique, and the influence of plasma treatment time on the amine group concentrations was investigated.

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We irradiated the reactive plasma to the carbon material having a three dimensional shape in order to examine about the extent of surface modification. In this case, it is problem what region is improved and whether the surface is modified uniformly. The box which has a small hole on upper side was used as a sample, which consists of the GC plate, a spacer and a upper plate. The characteristics on the inner surface of GC plate which was changed by plasma entering from its hole were investigated. The estimation of modification effect was carried out by contact angle to water at some points on its surface. When the sample was treated by plasma, the upper plate thickness t, the hole diameter 2r and pressure during plasma treatment were varied. As the thickness t was larger, effect on modifying the inner surface of GC plate was smaller and there was larger difference in its effect between the center and edge of the plate. In case that hole diameter 2r was varied, modification effect was increased and became uniformly by widening a hole. Even if 2r was considerably small (0.5mm) with 1mm of thickness, the modification effect was fairly large, which the contact angle decreased from 90°(untreated value) to 43° at the center (x=0mm) by plasma treatment. This is considered that the extent of modification effect depends on the quantity or condition of modification sources, which relate to the balance among the consumption, the movement and the generation of modification sources. And the interesting results was obtained that as the value of pressure was higher, all over the GC surface was more improved. It may be found that the inner part of the hole is not plasma but sheath region, and the modification source is radical in this case.

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This investigation was conducted on the surface modification of Glassy carbon(GC) material by R.F. glow discharge plasmas with the aim of investigating the surface nitriding for the GC materials with the nitrogen plasma. The contact angles for water to GC surface after the plasma treatment was measured. And their surfaces were analyzed by using Raman spectroscopy and ESCA. Nitrogen-plasma treatment makes the GC surface hydrophilic. The difference Δθ of the contact angles between those before the treatment (80°) and those at 30minutes after the treatment was investigated. Δθ is considered the effects of plasma treatment. As input power increased from 10W to 70W, the difference Δθ increased (on power electrode : from 46° to 63°, on earth electrode: from 32° to 58°). The composition ratios, O/C and N/C on the untreated GC surfaces were 0.0 and 0.0, respectively. Upon treatment with N₂ plasma, this ratio increased to 0.12(O/C) and 0.18(N/C) for the GC surface. Nitrogen atoms and oxygen atoms, namely, were introduced to the GC surface. Introduction of nitrogen atoms was caused by the nitrogen radicals and nitrogen ions. The oxygen atoms were introduced by nitrogen ions. Nitrogen ions were accelerated by the sheath voltage and bombarded the GC surface at high energy. As the result, the active and long life-time radicals were generated. The reaction between these radicals and the oxygen in the air took place when they were taken out from the treatment chamber to the air after plasma treatment.
The contact angle decreased by introducing the functional groups having nitrogen atoms and oxygen atoms onto the GC surface with nitrogen plasma. The surface nitriding of the carbon materials can be made easily with the short-time treatment of nitrogen plasma.

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Guidelines for surface functionalization of solid materials using plasma polymerization technique were made up in view of preparation of hydrophilic polymer films from oxygen- containing organic monomers. Profiles of deposition rates of the polymers on substrates along the monomer flow were obtained from the film thicknesses formed for a unit of time. The data brought about useful information to explore activity of the various monomers towards plasma polymerization. It also suggested the existence of optimum operative conditions to obtain the desired functions of the polymer films. Unsaturated bonds, especially triple bonds of the monomers led to high deposition rates with low wattage of radiofrequency power. Such local spot in the chemical structure was defined as "polymerization site." Oxygen atoms in the polar functional groups of the monomers, especially hydroxyl groups, remained in the resultant polymers under such soft plasma conditions. The oxygen atoms induced hydrophilicity not only from the atom contents but also from the spatial arrangement in molecular structures of the polymers. Thus, functional groups of the monomers such as -OH or -COON were defined as "functional site." Propargyl alcohol (2-propyn-1-ol) was found to be the most promising monomer at present. Addition of water in the same monomer influenced the resultant polymer considerably. Increased water content of the monomer reduced the deposition rate, while it raised the oxygen content, and resulted in enhanced hydrophilicity. It appeared that the unsaturated bonds of the polymer captured oxygen atoms from the plasma-dissociated water vapor.

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Plasma polymerization of tetraethoxysilane or perfluoro-n-hexane /hydrogen was investigated in order to reduce the pore size of NaA and ZSM-5 zeolite membranes and improve the gas selectivity through the membrane. Plasma polymerization was carried out in a bell-jar type of reactor with an inductive coupled rf (13.56MHz) power source. The effect of plasma condition on the deposition rate of plasma polymer was examined and the structure of plasma polymers was characterized by IR. The gas permeation through zeolite membranes modified by plasma polymerization was also investigated. Modified ZSM-5 zeolite membrane shows an improvement of the selectivity of gases by the reduction of the size of defect pore of the membrane.

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Wood is an organic materials which has been made from water and CO₂ by photosynthesis. Wood has a characteristic cell tissue, pore structure and chemical composition.These chraracteristic provide various properties, for exsample strength hygroscopicity, thermal insulation, sound insulation, and bio-degradation. However, wood has various shortcomings. The author studied production of wood materials of high performance and durability by plasma treatment and plasma polymerization.

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The plastic films are modified by various plasmas (CF₄, O₂, Ar, N₂) in order to know the difference of effects by kinds of their plasmas and the condition of the change of the surface characteristics with time after each plasma treatment is investigated in detail. Moreover, we developed the reduction method of its change with time. The condition of the surface modification by Ar plasma is similar to that of N₂ plasma. But, that by O₂ plasma was different from them. This reason is that the modification source is mainly ions on Ar plasma or N₂ plasma, and radicals on O₂ plasma. The contact angle modified by Ar plasma (N₂ plasma) became smaller than that by O₂ plasma; 0° (Ar plasma), 35° (O₂ plasma). The contact angle after the plasma treatment was seldom reduced even if time passed when plastic film was treated by Ar plasma treatment with heating. The bounding property of oxygen atoms was controlled by heating in the plasma treatment. On the other hand, the change with time was not reduced by CF₄ plasma with heating. But, treatment effect had been slightly increased. It is considered that the fluorine atoms which are causes of hydrophobic property are introduced much, however, are removed much.

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Using a diacrylate monomer as an ablation source, containing some additives such as cobalt (Co) and aluminum nitride(AlN) powders we prepared thin films by Nd:YAG laser in a 8 teslas magnetic field. When we prepared an about 3μm thick thin film by laser ablation, a rate of thin film formation increased about thirty times comparing the case used as a target with adding to Co particles of 10% in weight with that of used crude material . We suggest that heat conductivity of raw material increased on the imaginary with adding Co particles. And as the amount of Co particles increases, a rate of thin film formation increased. The properties of raw material and thin film were measured by near, intermediate and polarized FT-IR, Energy dispersive spectroscopy (EDS) and scanning electron microscope (SEM) and so on. It was found that polymerization of diacrylate monomer were carried out by intermediate FT-IR and Co element wasn't measured in thin film by EDS. Moreover polarized IR spectroscopy measurement showed that thin film formed by laser ablation using a target with Co particles had molecular orientation in plane of carbonyl and methylene groups as well as using crude material.

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In order to know the applicability of excimer laser ablation to the microphotoetching of collagen films, they were irradiated by an ArF (193nm) and a KrF (248nm) excimer laser through a mask. Well-defined patterning of excellent quality was attained only by the ArF laser, and its threshold fluence was 28mJ cm^-2. Periodic microstructures were formed on the etched surfaces, and their size and shape were dependent on the laser fluence and the number of pulses. The mean roughness of the etched surfaces increased with the fluence and the number of pulses with convex relations. The summit to summit distance of the periodic structures increased linearly with the number of pulses.

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Microcrystals of π-conjugated organic compounds, the size of which ranges from several tens nm to μm, have been prepared by simple reprecipitation from the solution, and their interesting optical properties such as size-dependent absorption and fluorescence, and nonlinear optical responses have been demonstrated.

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Photochemical conversion of 4-(2′-nitrophenyl)-1, 4-dihydropyridine derivatives was found to act as a chromophore for photosensitive polyimide precursors giving a dual imaging-mode characteristics. The sensitivities and contrasts for the negative and positive-working poly (amic-acid)'s were evaluated. The photochemical behaviors such as the quantum yields of the photoemission and the conversion, the reaction products and the transient species were studied. The mechanism of photosensitizing poly(amic-acid) was proposed.

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Issues in the LSI polyimide buffer coating process which uses photosensitive polyimide also as a mask of passivation film etching are reviewed. Change of lithography wave length from g-line to i-line causes the difficulty in the polyimide patterning. However, today's improved polymers, both ester type and ionic type, have enough ability to open 10um windows. Dry etching condition must be adjusted to reduce the reaction products because this process cannot apply hard asking. It is clarified that the adhesion to the molding resin after PCT is improved by F at the polyimide surface and is deteriorated by O2 plasma treatment. Fluorinated polyimide can keep good adhesion even after O2 plasma treatment.
Photosensitive polyimide can reduce the process steps in the LSI buffer coating process. Latest polyimides, both ester type and ionic type, has patterning ability for the application. RIE condition and Dost-treatment which are related to the issues of reaction products and the molding resin adhesion are significant.

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In the photosensitive polyimide(PI) application to the multichip module, MCM-D, two kinds of commercially available photosensitive PI, UR-3140 which has an ionic bond crosslinker and TL-530A which has an ester bond crosslinker, have been characterized.
The imidization temperature depends on the solvent release temperature and decomposition temperature of the incorporated crosslinkers. The ester bond PI requires a higher thermal treatment temperature than that of the ionic bond PI. Although the temperature of 100% imide conversion for each PI is below 300°C, in order to complete the outgassing and to obtain the desired mechanical properties, higher thermal treatment temperature and holding time, 400°C for ionic bond PI and 450°C for the ester bond PI, is needed. Furthermore, high temperature cure also drastically influence on their mechanical properties. Concerning the adhesion, the hydrophobic thin layer formed by argon (Ar) ion bombardment can protect the PI-metal interface from the invasion of water. The degree of roughness of PI surface formed by Ar ion bombardment and the chemical bonding between PI-metal seem to have no effect in improving the adhesion strength after pressure cooker test (121°C, 100% RH, 2.1atm for 100h).

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The concept of molecular composites was re-evaluated through the mechanical and morphological studies on the cast film forming from the rod/coil-typed block co-polyimide. The TEM observation has clarified that film modulus is dominated by the layer ordering of rod segments which are induced by the in-depth schrinkage through the cast film forming. These in-plane self-organizations should get much disturbed with the fabricational shift of from fibers or films to three-dimensional structural materials. Above result means that the request on how to keep up the in-plane alignments of the reinforcing units must be on further immediacy for the development of molecular composites-typed structural materials.

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Several newly developed photosensitive polyimides derived from 2-nitro- p-xylyleneoxyamine a are described. These fully imidized photoresists exhibit both positive working image and high sensitivity upon light irradiation. The most efficient polyimide examined is one prepared using polyalicyclic unit as dianhydride, where the photosensitivity is ca. 80 mJ/cm². The conversion of polyamic acid to polyimide, the thermal stability and the solubility of these polyimides are investigated, and compared with those obtained from the polyimides prepared with p-xylyleneoxyamine b.

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Photoconductivity of an aliphatic polyimide, PI(PMDA/DCHM), was investigated, comparing with that of an aromatic polyimide, PI(PMDA/ODA). An enhanced photocurrent was observed for the aliphatic polyimide. The quantum efficiency of the aliphatic polyimide and the aromatic polyimide was 2.1×10^-5 at 370nm, as 5.6×10^-6 at 420nm respectively, where the film thickness is 1.0μ. Initial photoresponse behavior was observed to investigate the photoconduction mechanism of the aliphatic polyimide, which shows a different behavior from the aromatic polyimide. The nature of the aliphatic polyimide film is investigated by using the model compounds. The emission spectra of the aliphatic polyimide shows the red-shifting with increasing of the excitation intensity, which indicates the existence of an aggregation of pyromellitic groups intra-and intermolecularly.

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Asymmetric biphenyl type polyimides (PI) were prepared by thermal imidization of polyamic acids (PAA) derived from 2, 3, 3′, 4′- biphenyltetracarboxylic dianhydride (a-BPDA) and p-phenylenediamine (PDA) or 4, 4′-oxydianiline (ODA). The degrees of molecular orientation, film densities, and dynamic mechanical properties of these PIs were compared with those of familiar PIs based on symmetric 3, 4, 3′, 4′- biphenyltetracazboxylic dianhydride (s-BPDA). PI(a-BPDA/PDA) cured at 350°C showed a T_g close to that of PI(s-BPDA/PDA) prepared under the same condition in spite of the bent chain structure of the former. Comparison of the PIs cured at 400°C manifested that PI(a-BPDA/PDA) has a T_g at 410°C (abrupt decrease in E′) whereas PI(s-BPDA/PDA) show no distinct T_g. Similar result was also observed for the ODA systems. The unexpectedly high T_gs of a-BPDA-based PIs were explained in terms of the restricted conformational change around the phenyl-phenyl bond in the a-BPDA unit. The difference of the E′ decrement at the T_g for both type of PIs are probably attributed to the difference of the intensity of intermolecular interactions. In PI(a-BPDA/PDA) thin film cured on a substrate, the segments unexpectedly align slightly to the film plane.

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