This investigation was conducted on the surface modification of the carbon material by the controlled R.F. glow discharge plasma with the objective of investigating the effects of plasma composition elements (plasma parameters). We looked into the effects of the light radiated from the plasma and the ions in the plasma mainly. The surfaces of the carbon material, which was glassy carbon (GC), was treated by the Ar plasma. The contact angles for water to the carbon material surface after the plasma treatment was measured. Moreover, its surface was analyzed by using Raman spectroscopy and ESCA. Also, we observed it by SEM. Ar plasma treatment makes the surface of the carbon material to hydrophilic and the contact angle decreased. By the effects of light radiated from the plasma, the contact angle of its surface after the plasma treatment decreased for the first time, and then increased with time. It is considered that the effect of light is the formation of the radical into its surface mainly. In three cases that the sheath voltage is changed, the ion density is varied and the plasma-treatment time is altered, the variation of the contact angle shows a similar tendency one another. It indicated that the effects of the three elements (the energy, the quantity and the number of times of the ion collision onto the surface of the carbon material) on the contact angle were considered to be the same.

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Hydrophilic plasma-polymer films were prepared from 2- propyn-1-ol (propargyl alcohol, PA) on surfaces of solid materials. The polymer enhanced its wettability by increasing the amount of water added to the PA monomer. Functional property of the polymer was first evaluated by coating of the plasma-polymerized PA (PPPA) film on a silica gel thinlayer plate. Chromatographic behaviors of some organic compounds was significantly altered by interaction between the polymer and the organic samples. Impregnation of chondroitin sulfate in the silica gel and following immobilization with the plasma-polymer exhibited affinities for Co²⁺, Fe²⁺, and Cu²⁺ depending upon the amount of chondroitin sulfate immobilized. PPPA showed humidity-electroconductive property that was usable as a sensing device of a hygrometer. An immobilized glucose oxidase (GOD) membrane was prepared by impregnating GOD in a porous membrane and coated with PPPA film. The membrane was attached to a dissolved oxygen electrode for composing a glucose sensor and the sensor worked with linear response up to the glucose concentration of 2mM.

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Improvement of the surface property of polypropylene by photochemical treatments was investigated. The combination of an ozone-treatment and a UV irradiation was effective for the grafting of methyl methacrylate and acrylamide onto polypropylene. The treated polypropylene could be dyed with usual dyes in water and it gave the affinity for usual adhesives in addition.

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Plasma polymerization of perfluoro-n-hexane, hexafluoroethane and tetrafluoromethane is investigated. The deposition rate of plasma- polymerized perfluoro-n-hexane increased with increasing discharge power up to 40W and then sharply decreased, while hexafluoroethane and tetrafluoromethane hardly polymerized. Addition of hydrogen or methane increased the polymer deposition rate because of hydrogen scavenging of fluorine atoms formed in the plasma.. A maximum in the deposition rate was observed in the 40 mol% hydrogen or in the 20 mol% methane addition to perfluoro-n-hexane or hexafluoroethane. FTIR and XPS spectra showed plasma-polymerized membranes have the crosslinking structure. The gas permeation through plasma-polymerized membranes deposited on zeolite, alumina-gel membrane and porous polycarbonate substrate is also reported.

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CFC-113 is known to be difficult to polymerize as a single monomer when treated under conventional plasma polymerization conditions. However, we found that by mixing it with substances with similar chemical structures, such as acethylene (C₂H₂), ethylene (C₂H₄) or ethane (C₂H₆), there are polymerized at a higher deposition rate. We observed one significant aspect of this reaction is that the copolymerization of C₂H₂ can reach deposition rates up to 9000 Å/min, we also observed the higher deposition rates of CFC-113 and hydrocarbons polymerized as a function of number of hydrogen molecules such as C₂H₂>C₂H₄>C₂H₆. A reaction pathway is proposed in which fluorine atoms derived from CFC-113 react rapidly with hydrocarbon producing free radical intermediates which can subsquently polymerize.

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Polymer powders, poly(methyl methacrylate) (PMMA) and polyamide (nylon 6, PA), were treated by four kinds of non-polymer-forming plasmas, Ar, O₂, CF₄, and CCl₄. The greatest weight loss was observed in O₂-plasma treatment due to its effective etching. In CF₄ plasma at the flow rate of 10 cm3(STP)/min, the molecular weights of PMMA and PA were reduced effectively. From the analysis by X-ray photoelectron spectroscopy, a new peak that may be assigned to acid fluoride was found, which was resulted from the decomposition of ester and amide groups in PMMA and PA, respectively. In CCl₄ plasma, polymerization took place preferentially.

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This investigation was conducted on the surface modification of various carbon materials by R.F. glow discharge plasmas with the aim of investigating the difference of the surface treatment effects due to the structural disparity of the carbon materials with the reactive plasma. The surfaces of carbon materials, which were glassy carbon (GC) and artificial graphite (AG), were treated by O₂ plasma or Ar plasma. The contact angles for water to each carbon surface after the plasma treatment were measured. And their surfaces were analyzed by using Raman spectroscopy and ESCA. Also, we observed them by SEM. Plasma treatment makes the two carbon materials hydrophilic. The contact angle decreased from 79.5° to 5° by O₂ plasma(GC, input power: 30W) and from 80.7° to 31° by Ar plasma(GC, input power: 30W). The contact angle decreased from 120.5° to 7° by O₂ plasma(AG, input power: 30W) and from 120° to 27° by Ar plasma(AG, input power: 30W). It is considered that the plasma treatment effects increase in case that the volume of the edge carbon, which has graphite-like layer, is large.

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When carbon materials of various shapes are treated by plasmas, it is problem which area of the carbon surfaces is modified and whether the surface is modified uniformly or not. In order to investigate the modified area in this case, we treated the sample which is a cavernous box having a hole. The material of various shapes is simplified in the sample of this shape. This sample consists of two carbon plates and a spacer. The specimen, spacer and source gas used in this experiment were glassy carbon(GC, 25×50mm), aluminum and O₂, respectively. The thickness of the spacer, equal to the gap of the GC plates, were variable from 0.5mm to 5mm. Property of the inner surface of the GC plate was estimated using the contact angle of water, its elapsed change and SEM photographs. The contact angle before treatment was about 90°. When the hole was 1mm in diameter and the gap d between the GC plates was 0.5mm, the contact angle near the center of the inner surface of the GC plate was 38°, and one at the term was 90°: only the area near the center was modified. With 5mm of the gap d, the contact angle at any place of the GC plates was constant at the value of 32°: all over the inner surface was modified uniformly. The degree of the surface modification in the sample (box) depends on the condition of the generation and removal of the modification sources formated by the plasma.

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Glassy carbon(GC) was treated by radio frequency(13.56 MHz) glow discharge plasma with heating it in order to investigate the heating effects. Source gases were CF₄, O₂ and Ar. Treatment time and heating temperature of the GC plate were 30 minutes and 200-500°C, respectively. The surface property before and after the plasma treatment was estimated by the contact angle of water to GC surface, its elapsed change and ESCA spectra of GC surface. In the surface modification by plasma, the contact angle changes with time after the plasma treatment, that make it difficult to use. Against this, in case of CF₄ plasma or O₂ plasma, the contact angle after the plasma treatment was constant even if time passed when GC was treated by these plasma with heating it. The elapsed change was reduced completely because the bounding property of both fluorine atoms and oxygen atoms was controlled by heating in the plasma treatment. On the other hand, the elapsed change was not reduced completely by heating with Ar plasma. It is considered that the oxygen atoms are introduced onto the GC surface after the plasma treatment when it takes out of the treatment chamber to air: the bonding property of them can not be controlled by heating in treating it by plasmas.

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A Chlorofluorocarbon was converted to a solid state substance for the purpose of nontoxic treatment and resource of specific freon waste. Experiments were performed by means of plasma polymerization from CFC113 (Trichlorotrifluoroethane ) and n-hexane mixtures. The maximum weight deposition rate of the film from CFC113 and n-hexane is 1.5×10^-3mg cm^-2 s^-1 at a two-one weight mixing ratio of CFC113 and hexane in the flask tank. This deposition rate is about 10 times as large as that from n-hexane itself The 16% weight amount of gas mixture introduced into the reaction chamber was converted to polymeric film on the lower electrode at the preparation condition. Solidification recovery in the whole chamber was more than 50%. Results of XPS and IR measurements indicate the existence of C-F and C-Cl covalent bonds in the films. UV-VIS spectra of the films were significantly different from that of n-hexane itself.

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Polyacrylate films were prepared by Nd: YAG laser ablation in the magnetic field(15tesla) using the liquid-crystalline diacrylate, 1, 4-phenylene bis{4- [6-(acryloyloxy)hexyloxy]benzoate}.The structure and molecular orientation of films were studied by IR spectroscopy, thermal analysis and polarized IR spectroscopy. It was found that the deposited diacrylate monomer on substrate after the laser ablation was polymerized at 413K, because the vinyl absorption bands at 1640, 1420cm^-1 disappeared. Moreover polarized IR measurements showed that molecular orientation of films was induced by the magnetic fields, because the differential spectrum at --CH₂, -CO bands and aromatic ring was given.

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We have investigated the photochemical reaction in the external photon field induced with KrF excimer laser (λ=248nm) for the bis(ethynylstyryl)benzene (BESB) films deposited by a molecular beam deposition technique. The cis-cis isomer crystalline films have grown on the KBr (001) substrate without laser irradiation. The laser irradiation to the film surface after and during deposition at the substrate temperature of 25°C caused the cis-to-trans photoisomerization and gave amorphous films due to disordering of the molecular arrangement. On the contrary, the photoisomerized trans-trans isomer crystals were found to be grown upon the irradiation during deposition at the substrate temperature of 60°C. These results indicate that the applied photon field to the molecular beam and the substrate temperatures during deposition play a significant role in the
film structures.

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The formation of radicals on the surface of poly(ethylene naphthalate) (PEN) and poly(ethylene terephthalate) (PET) films after KrF excimer laser ablation was investigated by measurements of electron spin resonance (ESR) and by analyses of surface reaction with a vinyl monomer at a cryogenic temperature. The ESR spectrum of the ablated films in a sealed tube showed a broad peak. Acrylic acid ester and styrene derivatives were immobilized on the ablated and fragment-deposited surfaces through chemical bonds.

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Non-polymer organic thin films such as copper-phthalocyanine (CuPc) and 4-dialkylamino-4′-nitrostilbene (DANS) were fabricated by KrF laser ablation. Changes in the chemical composition and structure, and in the crystallinity were studied for various laser ablation conditions. Crystalline thin films with accurate composition transfer from the target material were deposited when reducing the laser ablation fluence close to the ablation threshold fluence of -20mJ/cm². Semiconductor characteristics of CuPc thin film was examined in a Schottky diode.

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Upon exposure to N₂ laser light, a gaseous mixture of methyl acrylate (MA) and carbon disulfide (CS₂) deposited sedimental aerosol particles on a glass plate placed at the bottom of the irradiation cell, together with a thin film on the surface of an optical quartz window. Aerosol particles deposited from the gaseous mixture was spherical with a mean diameter of ≈0.3μm. The mean diameter and the product yield deposited from a gaseous mixture of MA (50Torr) and CS₂ (30Torr) gradually increased with increasing irradiation time of N₂ laser light. IR spectrum of the sedimental aerosol particles showed the bands characteristic of poly(methyl acrylate), indicating that MA is polymerized into the aerosol particles produced from CS₂.

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Plasma deposition of organic thin films represents a flexible strategy for tuning the surface chemistry of materials for specific applications. The advantages of such films are summarized, surface characterization is discussed and specific applications for biology and medicine are reviewed.

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The recent progress of UV-laser photoablation is reviewed with the sake of clarifying the various regimes of irradiation which are of interest for new processes. "Fast", "Slow" and "Pre-" ablation regimes are evidenced by Laser Ablation-Sputtered Neutrals Spectrometry (LA-SNMS). Mass spectra of a series of polymers. have been obtained. Sub-micron periodic structures and examples of microfabrication (microlens arrays) are presented. The recent developments of photoablation of polymers with the UV radiation of excimer lasers is reviewed. LA-SNMS is shown to be a very promising detector for future work in the photoablation of polymer area. The gases emitted by the ablative interaction are measured in ultra high vacuum conditions. Some polymer spectra (Kapton, Upilex, PEN) are presented and interpreted. The work on formation of submicron periodic structures is entering into a new phase with the discovery of systems giving visible structures which are studied by visible light diffraction. Photoablation is seen as an attractive tool for future development of microfabrications. The example of microlens arrays is presented. For clarity we define three main regimes of irradiation which we call: Pre-ablation, Slow Ablation and Fast Ablation. It is important to note that each regime of irradiation has evidenced interesting processes for the applications.

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