Dependence of radical initiators on polymerizations of o-, m-, and p-vinylphenol (OVP, MVP, and PVP) was investigated. Initiator generating the carbon radical such as AIBN induced polymerizations of these monomers to give fine polymers. That is; MVP and PVP gave polymers with high molecular weight (21,000∼53,000), while OVP gave polymers with relatively low molecular weight (7,600∼9800). The results of the spectroscopic investigations of the polymers thus obtained suggested that all of the polymers consisted of the structure formed through the normal vinyl polymerization mechanism. Initiator generating the oxy radical such as BPO as well as the thio radical such as tetraethylthiuram disulfide did not induce appreciable polymerizability. A reasonable radical polymerization mechanisms for OVP, MVP, and PVP were considered from the results of the kinetic investigations of the polymerization reactions for these monomers. Copolymerizations of OVP, MVP, and PVP with styrene or methyl methacrylate by using AIBN as initiator were investigated. The monomer reactivity ratios and Q-e values for OVP, MVP, and PVP were determined, respectively. The copolymerizations generally gave copolymers with relatively high intrinsic viscosity not only for MVP and PVP but also for OVP without distinction. Cationic polymerizations of OVP, MVP, and PVP with boron trifluoride etherate as initiator were investigated. As the result, it was of interest that on the cationic polymerization only PVP gave polymers with high molecular weight (66,000∼192,000), whereas both OVP and MVP gave polymers with low molecular weight (∼3950 for OVP and ∼710 for MVP, respectively). The results of spectroscopic investigation for the polymers thus obtained indicated that PVP polymers consisted of the structures formed through the normal vinyl polymerization mechanism, while OVP and MVP polymers contain considerable portion of the structures due to the reaction of the vinyl group and the phenol nucleus. The rate of cationic polymerization and the molecular weight of the polymer decreased in the order PVP >> OVP > MVP. Plausible polymerization mechanisms were considered.

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One of some critical issues for ArF immersion lithography was leaching of resist components to water fluid. To decrease the leaching amount, increase hydrophobicity of Photo Acid Generator (PAG) was one of the most effective methods. The hydrophobicity of PAG was detected by simulating Log-P value and measuring Retention Time (RT) on reversed phase chromatography. However, simple high hydrophobic PAG indicated high defect number. The improvement of this issue was achieved by introducing acid cleavable group into PAG cation frame. It may suggest that PAG material proposed on this study showed low leaching amount and low defect risk as new concept for ArF immersion resist.

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Multilayer resist process has been recognized as one candidate to realize high aspect ratio resist pattern. As one important control factor, strain and stress matching in multilayer structure should be taken into consideration. By using a strain gauge, the strain of dry film resist (DFR) in single, double and triple layer structure are measured as a function exposing time. The strain of DFR increases in proportion with the exposure dose but slightly decrease as number of multilayer. The stability of DFR multilayer structure is discussed.

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One serious problem for immersion lithography is micro bubble adhesion which is responsible for various exposure failures. In immersion lithography, it seems reasonable to suppose that organic contamination of lens surface brings about micro bubble adhesion onto them. Therefore, this study is intended as an analysis of adhesion and removal of micro bubbles on quartz surfaces by the contact angle method. We discuss the adhesion and removal behavior of micro bubble on the point of the balance model of surface energy. In the consequence, the micro bubbles are more likely to adhere to the organic contaminate on the quartz substrate. Keeping cleanness of a lens surface is necessary in order to prevent the micro bubble adhesion.

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The crystallization of ITO layer was progressing gradually in storage at the room temperature. On one hand when ITO layer on PC substrate was still amorphous in a short-term storage (case 1), surface resistance of ITO layer decreased by the post-annealing treatment; on the other hand when ITO layer on that was mostly crystalline in a long-term storage (case 2), surface resistance of ITO layer increased by that treatment. Either of post-annealed ITO layer had the compressive internal stress though case 1 showed higher internal stress than case 2. Regarding case 1, ITO layer was not damaged because of the same level elongation as PC substrate during the post-annealing treatment and surface resistance of it decreased. Regarding case 2, while PC substrate elongated as the same level as case 1, ITO layer elongated less than case 1 during the post-annealing treatment. Microcracks were generated in ITO layer due to the stress. Surface resistance might increase because of microcracks.

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Nano-scale deformation of resist film surface is analyzed by using atomic force microscope (AFM) in a humidity controlled chamber. It is clarified that the condensation size of polymer aggregates of resist material are slightly changed due to humidity change. As one major factor, Laplace force acting among polymer aggregate due to surface adsorbed water is discussed. The deformation model of condensed polymer aggregates is proposed.

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By contact angle method, surface energy of Si(100) wafer is measured with lapse of time in ambient condition. The polar component γ_s^pof surface energy increases drastically but the dispersion component γ_s^d decreases. Surface energy γ (=γ_s^d+γ_s^p) gradually decreases. The surface energy change is mainly reflected with native oxide growth on the Si substrate. The polar and dispersion component of resist film corresponds mostly to those of surface energy of Si(100) after 10h exposing time to air. The spin coating condition can be designed effectively base on the surface energy model.

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Photochemical vapor deposition in the optical near field was employed to fabricate nanometric Zn dots on a sapphire substrate. A nonadiabatic photochemical process was used to excite molecular vibrational states in optically inactive zinc-bis(acetylacetonate) (Zn(acac)₂) vapor. Dependence of the deposition rate on the separation distance, d, between the apex of the fiber probe and the substrate was investigated. At d > 5 nm, the dissociation rates of Zn(acac)₂ decreased with increasing d due to the transition probability of ground-state Zn(acac)₂ to excited vibrational states induced by the nonadiabatic photochemical process. At d < 5 nm, the deposition rate decreased with decreasing d, which was attributable to an insufficient supply of gaseous Zn(acac)₂ molecules in the gap space between the fiber probe and the substrate.

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Two polymeric fullerene derivatives and corresponding fullerene grafted, PAG bound polymer resists (HS-EM-HM/Fulle-PAG) based on hydroxystyrene (HS), 2-ethyl-2-adamantyl methacrylate (EM), 3-hydroxy-1-admantyl methacrylate (HM) were prepared and characterized. The preliminary lithographic performance of these polymers were conducted with a contact printer, e-beam, and structure-function relationships were also studied. The results demonstrated that the thermostability and glass transition temperatures increased, but sensitivity and resolution decreased. Further investigations about microstructure modification, composition effect, exposure conditions on the lithographic properties will be carried out.

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We discuss adhesion and removal properties of micro bubbles based on thermodynamics. It is important to consider the remove technique of micro bubbles from resist surface. A micro defect on a resist surface acts to enhance the adhesion of micro bubble on to them. It is cleared that the defect such as a solid particle and a resist fragment are more likely to capture the micro bubbles due to pinning effect. It is clarified that the removal mechanism can be explained based on surface energy balance model. Consequently, one can safely state that the removal of micro bubble from the F2 excimer resist film is required a certain external load. The capture mechanism of micro bubbles at the micro defect is analyzed based on the pinning effect.

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Liquid drop spreading is effective phenomenon for understanding nature of wetting processes such as pattern development, etching, cleaning, immersion lithography and so on. Liquid spreading can be measured by contact angle measurement. Spreading coefficient c in Neumann model is estimated for each film surface. Results obtained in this experiment indicate that the liquid drops on resist surfaces are more likely to spread compared with those on the inorganic substrates.

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The sub-micrometer core-shell microcapsule is synthesized by interfacial polymerization method, with photocrosslinkable resin TMPTA and photoinitiators ITX, TPO encapsulated as core functional compounds. FT-IR detection shows the polyurea chemical structure of the microcapsule shell, and TG analysis verifies that the microcapsule is thermal stable below 230°C. The photopolymerization process in microcapsule is measured quantitatively from the variance of the C=C bond absorbance at 1635cm^-1. The photopolymerization degree in microcapsule increases with rise of exposure time, and achieves stabilized photopolymerization percentage of 39.4% after 30s, which is lower in comparison with 60% of the unencapsulated resin/photoinitiators mixture exposed after 15s. The decrease of photopolymerized degree in microcapsules is ascribed to the UV irradiation attenuation when transmitted through the microcapsule shell. The photosensitive microcapsules can act as basic functional cells in responding to photo stimuli at sub-micrometer scale.

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From gaseous mixtures involving iron pentacarbonyl (Fe(CO)₅) and carbon disulfide (CS₂), spherical ultrafine particles involving organometal compounds were synthesized under light irradiation at 313 nm. Chemical structure and chemical composition were changed by post-exposure with UV light and by the application of a magnetic field. By the post-exposure with 266 nm light upon the deposited particles, volatile fragments such as Fe(CO)_n (n=1∼3) were evolved in addition to CO. The particle size was effectively diminished to as small as 58 nm by shortening the irradiation time up to 1 s. Upon exposure to intense laser light, photochemical reaction during aerosol particle formation changed dramatically and gaseous mixtures involving Fe(CO)₅ produced magnetic particles. By controlling the convectional flow of the entire gaseous sample, linearly aggregated particles (i.e., particle-wires) were successfully produced. Potential applica- tions of the particle-wires to nanolithography and in constructing nanodevices were discussed briefly. From solid materials such as poly(dimethylsilane), spherical particles were produced in the atmosphere of trimethylsilyl azide by the aid of laser ablation. Technical advantages in producing spherical particles from solid materials were also discussed.

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Most recent topics of EUVL are that AMD demonstrated first functional device using ADT in Albany to integrate SRAM cells in the full chip cell of Typhoon, and IMEC demonstrated functional 0.186 μm² 32 nm node SRAM cells with extreme ultraviolet lithography (EUVL) on the contact-hole level. The recent topics and prospect for extreme ultraviolet (EUV) lithographic technology are described of the exposure tools, EUV source, mask inspection, and resist development. EUVL source technology has been advanced in these three years to increase the power and to extend the beam stability. For the mask, defect inspection system development was advanced by a several institute to detect the defect to find the threshold condition of printable and non-printable. As for a resist, the resolution and sensitivity were refined to become close to satisfy the required specification for 32-nm node. However LWR has not been satisfied the specification yet. Furthermore, since EUVL will be pushed for 22-nm node and it should be use until 11 nm node in the ITRS, EUVL technology has to be ready around 2012 to transfer to the pilot line. For 22-nm node, the resist has not been satisfied yet. Thus it needs large steps to develop the resist material and process for 22-nm node and below down to 16-nm node in EUVL.

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The nature of plasma-induced surface radicals formed on a variety of organic polymers have been studied by electron spin resonance (ESR), making it possible to provide a sound basis for future experimental design of polymer surface processing using plasma treatment. On the basis of the findings from such studies, several novel bio-applications in the field of drug- and biomedical- engineering have been developed. Applications for drug engineering include the preparation of reservoir-type drug delivery system (DDS) of sustained- and delayed-release, and floating drug delivery system (FDDS) possessing gastric retention capabilities, followed by preparation of "Patient-Tailored DDS". Furthermore, the preparation of composite powders applicable to matrix-type DDS was developed by making a mechanical application to the surface radical-containing polymer powders with drug powders. In applications for biomedical engineering, the novel method to introduce the durable surface hydrophilicity and lubricity on hydrophobic biomedical polymers was developed by plasma-assisted immobilization of carboxyl group-containing polymer on the polymer substrate. The surfaces thus prepared were further used for the covalent immobilization of oligo-nucleotides (DNA) onto the polymer surfaces applicable to constructing DNA diagnosis system, and also plasma-assisted preparation of functionalized chemo-embolic agent of vinyl alcohol-sodium acrylate copolymer (PVA- PAANa).

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A novel molecular glass based on tetrahydropyran (THP)-protected G1 dendrimer (3) was designed and synthesized as a positive-type chemical amplified resist. The dendrimer 3 involving a photoacid generator and an acid quencher showed a high sensitivity (D0: 33 mJ/cm²) and a high contrast (8.3), and could fabricate 3 μm line-and-space pattern with a 365 nm light (i-line) exposure tool. Moreover, a 2.38% aqueous tetramethylammonium hydroxide (TMAH) can be used as a developer.

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