Magnetron-AF (e.g., 15 kHz) plasma polymerization with a coaxial circular arrangement of magnetic field has a unique advantage that no deposition occurs onto a part of electrode surface corresponding to the toroidal glow, which enable us to operate the stable magnetron plasma polymerization continuously for a long period of time. Together with the confined glow that remarkably reduces the contamination of the reactor; the magnetron plasma polymerization has been shown to be one of the most effective modes of plasma polymerization in industrial scale operation. When the magnetron plasma polymerization is used in laboratory experiments, successful operations can be easily scaled up to industrial scale operations by maintaining parameters of the magnetron discharge and, if necessary, increasing the number of discharge units, in stead of enlarging the discharge unit.

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  Vapor deposition polymerization (VDP) of poly(p-xylylene) and its derivatives is discussed. The process, known as parylene technology, is a thin film vacuum deposition method, utilizing [2₂]-paracyclophanes as precursor compounds and it is approximately forty years old. Today, thanks to its applications in miniature electromechanical systems (MEMS) and all organic semiconductor (AOS) technologies, it is a subject of a strong renewed scientific interest.
  The emphasis of this review is put on the mechanism of parylene deposition as well as on this process' applications. As far as the deposition mechanism is concerned it is discussed in terms of both chemical reactions and physical phases and phenomena involved. The occurrence of two different mechanisms, of which the solid phase addition polymerization takes place at temperatures below monomer melting point, is particularly stressed. The diversity of parylene uses, both present and future, is also discussed with an attention on the development of future biomedical, MEMS and AOS applications.

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  Surface modification using plasma treated and graft polymerization is versatile process, with systems on the market capable of treating everything from polymer, metal, and ceramic substrates. The major advantage is that the modification is caused no substrate damage or bulk property changes. This is a very effective method to modify the surfaces of biomaterials to achieve desired physical or mechanical properties, or to induce a specific response when the device is placed in the body. They offer attractive possibilities for developing new biomaterials and for improving the performance of existing materials and devices. Hence, in this review, we describe the application of plasma treatment and graft polymerization on biomaterials field. The various applications are discussed in the following: (1) easy stripped-off wound dressing, (2) porous three-dimensional temporary scaffolds, (3) quartz crystal microbalance (QCM) base biosensors, and (4) covalent immobilization of glucose oxidase onto inorganic substrates

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  Plasma-surface modification is a technique to treat surfaces of various materials for a wide variety of applications. However, the treated surface layer is so thin that the nature of the treated surface decays gradually with time. The reasons for the decay of plasma-treated surfaces are considered to be (1) rotation and migration of surface moieties containing functional groups into inside of the material and (2) disappearance of relatively low-molecular-weight substances including weak boundary layer (WBL) formed in the plasma treatment. However, the decay behavior depends on materials nature, plasma condition, storage condition, and so on, and the precise mechanism is still unknown. The decay is also observed on inorganic material surfaces. Promising methods for the prevention of the decay, at the present stage, may be surface cross-linking and immobilization or grafting of suitable polymers on the surface.

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  Polymer thin films were sputtered with thermally stable polymer targets onto a copper and glass slide substrate with a conventional RF sputtering apparatus. Polymer structures and adhesion and tribological properties of these polymer thin films were evaluated.
  The pull strength between evaporated metal films and sputtered poly(tetrafluoroethylene) (PTFE) thin film was higher than that between evaporated metal thin films and the bulk PTFE. This difference was apparently due to differences in chemical bonding states between the sputtered PTFE thin film and the bulk PTFE. The PTFE thin films were sputtered at various conditions. Surface free energy of the PTFE thin films decreased with increase of fluorine content of the PTFE thin films. Although dispersion force component of the surface free energy slightly decreased, dipole force component dramatically decreased with increase of temperature of the substrate.
  Polymer thin films were sputtered onto copper substrate with two polyimide (Kapton-V^TM and Upilex-S^TM) targets. Argon and nitrogen were introduced into the sputtering chamber for the sputtering gases. Sputtering rate of the polymer thin film with argon gas showed highest value at a pressure of 0.67 Pa. However, the sputtering rate with nitrogen gas showed highest value at a pressure of 8 Pa. Nitrogen content in the thin film sputtered with the nitrogen gas (N₂ sputtered thin film) increased compared to that sputtered with argon gas (Ar sputtered thin film) and target material. Friction coefficient and wear durability of the N₂ sputtered thin film were higher than those of the thin film sputtered with the Ar sputtered thin film. The pull strength between the N₂ sputtered thin film and copper substrate was higher than that between the Ar sputtered thin film and copper substrate. In addition, the N₂ sputtered thin film was introduced between the copper substrate and Ar sputtered thin film (Ar/N₂/Cu laminate). The pull strength of this laminate showed higher value than that between the Ar sputtered thin film and copper substrate.

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  From the viewpoint that chemical composition at the film surface is different from that in the film bulk even if the same polymers are used, plasma surface modification of poly (oxybenzoate-co-oxynaphthoate) (the trade name is Vecstar) has been investigated. What chain end groups are present at the face of the Vecstar films, how much concentration of the chain end groups locates at the face, and how chain end groups contribute to plasma modification have been discussed. A combination of the EB irradiation or supercritical CO₂ modification and plasma modification made the impossible possible in adhesion between Vecstar OC film and copper metal. This improved adhesion may be due to contribution of end groups formed newly by the EB irradiation or supercritical CO₂ modification.

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  If TiO₂ particles are used as components of paint without any surface modification, binding resin of the paint will be easily decomposed by the photocatalytic activity of the particles. In this work, plasma polymerization of octamethylcyclotetrasiloxane as a siloxane monomer is tried to form thin layer stable to the photocatalytic activity on the surface of TiO₂ particles. The plasma-polymerized layer containing Si-O and Si-C bonds is formed on the surface of the particles and shows stability to the photocatalytic activity of TiO₂. The particles surface-modified with the plasma polymerization exhibit visible-light activity. The visible-light activity is originated from carbon doping which brings about in the particles during the plasma polymerization, and is thermally stable to be maintained after annealing at 673 K.

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  Hydrophilic silicon oxide film was formed at a low temperature (below 50°C) condition by pulsed plasma chemical vapor deposition (Pulsed Plasma CVD) method using by Si(CH₃)₄ (TMS), O₂ and Ar as reactant gases. Pulsed Plasma CVD is the technique of preparing film by pulsed rf power supply and pulsed gas supply. And we found that Pulsed Plasma CVD technique is able to make a nanoscale roughness on the silicon oxide film. The roughened surface tended to be more hydrophilic than the smooth surface. Hydrophilic silicon oxide film could be used for demist glasses, and it made the stain go away easily. Sometimes when the film deposited on a mold, a nanoscale surface roughness was able to improve mold separation force.

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  Micro-apertures for annular pupil on electron optics have been developed using a focused ion beam technique to realize an increase in the depth of focus, aberration-free imaging and separation of amplitude and phase images under scanning transmission electron microscopy (STEM). A tantalum plate 30 μm thick was used as the annular pupil material in the present experiment. The apertures were designed with various outer diameters from φ120 μm to φ60 μm and at inner diameter of 80% outer diameter. Fabricated apertures were characterized by a scanning ion-beam microscope and a scanning electron microscope. Apertures were successfully obtained at the designed size, although the slits of the pupils were slightly tapered by the ion-beam etching process. These annular pupils were loaded on a STEM and confirmed to display no charge-up phenomenon by observation of the projection image on a scintillator using a CCD camera.

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