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Modification of a selective area of a fluororesin surface was accomplished by using ArF excimer laser radiation and a boron complex with oleophilic or hydrophilic functional groups. The chemical stability of fluororesin is attributed to the presence of C-F bonds. The F atoms were abstracted by B atoms selectively from the area irradiated with excimer laser radiation and were replaced with the desired functional groups. In this modification, B(CH3)3 and B(OH)3 were used: a boron compound with methyl groups to generate an oleophilic surface, and one with hydroxyl groups to generate a hydrophilic surface. As a result, the resin surface exposed to ArF laser radiation becomes oleophilic or hydrophilic. Both samples were bonded to stainless steel plates with an epoxy bonding agent and the tensile shear strength was 1.2 x 107 Pa in both cases.

Polypropylene (PP) surface in water was photochemically modified to render it hydrophilic using ArF excimer laser radiation. The chemical stability of PP is attributed to the C-H and C-H3 bonds present. Thus, it is considered that H atoms are selectively pulled out from the area irradiated with ArF excimer laser light and are replaced with OH functional groups in the presence of water. In this treatment, the irradiated sample becomes hydrophilic with enhanced adhesion properties. The experimental conditions for this surface treatment were ArF laser fluence of 12.5 mJ/cm2 and a shot number of 10000. The treated PP and stainless steel were bonded with epoxy adhesive and the tensile shear strength was 46 kg/cm2.

An oxidizing agent is needed for silicone oil to be photo-oxidized with Xe2 excimer-lamp. However, the lamp light did not reach the silicone oil on the surface of the substrate satisfactorily, and the photo-oxidation reaction of the silicone oil layer was hard to take place properly. In order to find the appropriate conditions for supplying the proper amount of an oxidizing agent to silicone oil, the vacuum ultraviolet light that passed the silicone oil layer was made fluoresce in the phosphor to monitor the progress of the photo-oxidation reaction. As the vitrification by photo-oxidation reaction of the silicone oil layer improved, the fluorescence intensity of the phosphor increased. While monitoring the change of the fluorescence intensity, the supply of the oxidizing agent and the irradiation time of the vacuum ultraviolet light were controlled; as a result, the new method to efficiently form a transparent, photo-oxidized thin film has been established.

The "Offshore Electrolysis Plant" has been proposed to prevent a fuel crisis and global warming simultaneously and to make a peace loving, sustainable society without resource wars. This on-site electrolysis plant is located on the raw material called "seawater" and is equipped with a windpower station. Utilizing offshore wind energy and seawater, sodium is produced as a solid fuel on site by molten-salt electrolysis and transported to a power consumption place on land, where the sodium will be made to react with water to produce hydrogen for power generation. Many by-products such as fresh water, magnesium, hydrochloric acid, sulfuric acid, and sodium hydroxide are prepared electrolytically; the sodium hydroxide is supplied to the soda industry as a raw material. Furthermore, the plant is designed to use all the by-products efficiently, to attain "Zero Waste", to decrease the energy loss in production, storage, and transportation, and to improve the efficiency of the whole system.

Area-selective nucleation of copper onto fluorocarbon–resin surface was demonstrated by using an ArF excimer laser and copper–sulfate (CuSO4) aqueous solution. Pyramid-typed shaped nuclei of copper were initially formed on even an inert surface of fluorocarbon–resin in the same way as semiconductor or metal surfaces. Interface of copper nuclei and fluorocarbon–resin was chemically bonded through oxygen which was photodissociated from water in copper–sulfate aqueous solution under ArF excimer laser irradiation. The modification cannot be successful without our previous defluorination efforts using ArF excimer laser-induced chemical reaction.

A powerful adhesion of teflon featuring its excellent corrosion resistance and stainless steel was performed by using an epoxy resin-based bonding agent. Adhesion strength was 120 times more than that of untreated teflon, which has virtually no affinity with chemicals and solids.

A thin layer of water or hydrogen peroxide solution, which was formed on a pure aluminum substrate, was photodissociated by ArF excimer laser( λ =193nm) or Xe2* excimer lamp (λ = 172nm) light to photochemically oxidize the surface of aluminum substrate. The layer was formed by a capillary phenomenon between the substrate and a fused silica glass as an entrance window of ultraviolet light. Then, the layer was photodissociated by the excimer laser or the excimer lamp light irradiation to generate active oxygen; the surface oxidization was performed by the photo-induced active oxygen. The surface before and after modification was evaluated by the XPS analysis; the high densed photo-oxidization film was confirmed on the modified surface, compared with a natural oxidization film Furthermore, the contact angle with water became remarkably small, and it is seen that the treated surface was quite densely oxidized.

Large area surface modification of fluorocarbon resin was performed by ArF laser beam irradiation, and water or B(OH)3 solution for its practical application. To complete treatment in a short time and keep its cost lower, the total amount of photons that induce reactions was reduced by decreasing the laser fluence as well as shot number. Water or B(OH)3 was sandwiched between a fused silica glass and a fluorocarbon resin film to form a thin layer using a capillary phenomenon. The substrate was perpendicularly irradiated with ArF excimer laser through a cylindrical lens. By moving horizontally, the surface was continuously modified. The extensively modified sample was mounted to stainless steel with epoxy resin, and the tensile strength was measured. As a result, the adhesive strengths of the sample modified with water and the one with B(OH)3 solution improved 275 and 490 times that of the untreated sample respectively.

SiC exhibits a high resistance to heat and X-rays. With its characteristics, it is expected as a semiconductor material with which IC devices for car and space electronics can be developed. Minute pattern etching of SiC is, however, very difficult chemically or physically. Here, we propose a new photochemical pattern etching method, in which the crystalline SiC surface in an atmosphere of gaseous CIF3 was etched by patterned KrF excimer laser light. The KrF laser beams were irradiated to the SiC substrate: one parallel and the other perpendicular to the substrate surface. The parallel beam was used to dissociate CIF3 gas in the proximity of the substrate, and the perpendicular beam which was projected circuit pattern was used to locally excite the substrate. The line and space of the single crystalline SiC (3C-type) was 1 µm; etching depth, 1000 A.

The authors propose an energy cycle based on a renewable fuel. Magnesium is chosen as an energy carrier and is combusted with water to retrieve energy using many power devices. MgO, the combustion residue, is reduced back to Mg by laser radiation generated from solar and other renewable energy sources. They have achieved an energy recovery efficiency of 42.5% for converting MgO to magnesium, using a laser. Combined with a demonstrated 38% efficiency for converting an artificial sunlight source (metal halide lamp) into laser output energy indicates that the proposed energy cycle is already in a feasible range for practical use.

Excimer lasers provide high intensity beams in the ultraviolet wavelength region. Using these photons, it is possible to cut the molecular bonds in materials such as PMMA by photochemical reactions [1]. As the results of the photochemical reactions, the deposition of metals [2], semiconductors [3] and other compound materials [4–5] has been realized. In uv laser-induced chemical vapor deposition (uv CVD) of thin films the excitation of gas phase has been studied extensively in recent years. These methods are expected to be applied to a low temperature technique in new production processes. However, these methods involve some difficulties: the attachment of the photochemical product to the incident window of the laser beam might be an unavoidable problem in many cases. However, use of this process has led to some successful results.