Carbon Alloy Catalysts' (CAC), non-precious metal catalysts for the oxygen reduction reaction (ORR), were prepared from a polyhydroxyamide poly(3,3'- dihydroxybenzidine terephthalamide) (DHBTA) with iron phthalocyanine (FePc) via a poly-biphenylenebisoxazole (biPBO) composite, by carbonization at 800 °C under nitrogen flow. Monitoring of the carbonization process by elemental analysis and FT-IR implies that nitrile and carbonyl groups are intermediates for CACs, and that Fe accelerates carbonization. Obtained CACs showed high ORR activity when Fe content in the polymer increased. The catalytic activity for ORR was evaluated at the onset potential of -2μAcm. Especially, CAC derived from polyhydroxyamide with FePc (containing 3 wt% Fe) had an onset potential of 0.89 V, which is a higher value than those derived from phenolic resin blended with FePc. TEM and XRD analysis of the highly active ORR catalyst showed higher crystallinity and increased number of turbostratic carbons due to the increased Fe content during carbonization.

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Polyimide (PI) and poly(benzoxazole) (PBO) materials are widely used as stress buffer and rewiring cover layers to improve the reliability of semiconductors. With recent advances in this area, the chemical resistance of PI and PBO to organic solvents, acids and, in particular, strong bases is critical in avoiding penetration issues during the plating process. To address this issue, development work was focused on residual stress and adhesion to the substrate where selected adhesion promoters and cross-linkable compounds were tested. In this paper, a novel positive-tone photo-definable material that has excellent chemical resistance properties has been developed to meet these demands.

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A chemically amplified photosensitive polyimide (PSPI) based on poly(amic acid) (PAA), 9,9-bis[4-(tert-butoxycarbonylmethyloxy)phenyl]fluorene (TBMPF) as a dissolution inhibitor, and (5-propylsulfonyloxyimino-5H-thiophene-2-ylidene)-(2-methylphenyl)actonitrile (PTMA) as a photoacid generator has been developed. The PAA was prepare from 4,4'-(hexafluoroisopropylidene)diphthalic anhydride (6FDA) and 2,2-bis[4-(aminophenoxy)phenyl]hexafluoropropane (6FAPP). The PSPI consisting of PAA (84 wt%), TBMPF (8 wt%), and PTMA (8 wt%) showed high sensitivity of 45 mJ/cm² and high contrast of 12, when it was exposed to a 435 nm line (g-line), postbaked at 110 °C for 2 min, and developed with an aqueous alkaline developer, 2.38 wt% tetramethylammonium hydroxide solution with 5 wt% iso-propanol at 25 °C. A clear positive image of 4μm line and space pattern was printed on a film exposed to 200 mJ/cm² of g-line by a contact printing method and converted into the polyimide pattern upon heating at 250 °C for 1 h.

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An introduction of new materials has been the important breakthrough in each technology node. For the rapid development of novel materials, material suppliers have founded Consortium for Advanced Semiconductor Materials and Related Technologies (CASMAT) in 2003. CASMAT provides whole equipment for process of Back-end- Of-Line (BEOL), and applies new materials to 300mm silicon wafers. CASMAT evaluates, and reveals important characteristics of those materials, points out issues, also offers efficient solutions to material suppliers. As a result, they can shorten the research and development period of materials, and expand their business because of bringing new products to the market rapidly. As the examples, Test Element Group (TEG) masks and wafers, a quantitative evaluation method of adhesion strength, and an integrated solution for wiring with a polymer low-k material are presented here.

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Novel non-photosensitive polyimides were prepared from 3,4'-oxydiphthalic anhydride (a-ODPA) with a siloxane-containing diamine and 2,2-bis[4-(4-aminophenoxy)phenyl]propane (BAPP) at a very high solid content of 60 wt% for applications to screen-printable FPC cover layer materials. The random copolyimide showed an extremely low tensile modulus in addition to very high film toughness, thereby curling of FPC could be completely suppressed. The sequence-controlled copolyimide with the same chemical composition displayed a further decreased tensile modulus, which can be explained from a sea-island phase-separated morphology controlled by the siloxane block size. The siloxane-containing copolyimide solutions containing an additive showed good screen-printability without sacrificing other target properties.

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For developing thermally stable polymer films exhibiting high thermal conductivity, fluorinated polyimides (PIs) were hybridized via 'in situ hybridization method' and 'direct mixing method' with magnesium oxide (MgO) nanoparticles possessing high thermal conductivity and good insulating property. In the former method, MgO nanoparticles were spontaneously generated and precipitated in PI films by thermal decomposition of a soluble precursor, magnesium acetate tetrahydrate (MgAc). The Far-IR absorption spectra, WAXD patterns, and solid-state ²⁵Mg NMR spectra of PI/MgO hybrid films demonstrated that MgAc was thermally decomposed to MgO nanoparticles during curing up to 380 °C. In addition, the cross-sectional SEM images of the hybrid film showed that spherical MgO nanoparticles (average diameter : ∼50 nm) were homogeneously dispersed without aggregation in the hybrid films. The thermal diffusivities along the out-of-direction (α_⊥) of the hybrid films were measured using the temperature wave analysis, and their thermal conductivities (λ) were estimated from α_⊥, specific heats, and densities. For the hybrid films prepared by both the methods, the λ values are proportionally increased as the MgO content increase, and the λvalues are in good accord with the predicted values based on the Bruggeman's theory.

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A positive-type chemically amplified photosensitive poly(hydroxyimide) (PSPHI) based on the partially imidized poly(hydroxyimide) (PHI) prepared from 4,4'-[p-thiobis(phenylenesulfanyl)]diphthalic anhydride and bis(3-amino-4-hydroxyphenyl)-sulfone, 9,9-bis[4-(tert-butoxycarbonyl-methyloxy)phenyl]fluorene (TBMPF) as a dissolution inhibitor, and (5-propylsulfonyloxyimino-5H-thiophen-2-ylidene)-(2-methylphenyl)acetonitrile (PTMA) as a photoacid generator has been developed. This PSPHI consisting of the partially imidized PHI (80wt%), TBMPF (16 wt%), and PTMA (4 wt%) showed high transparency in the 450 nm wavelength and high refractive index of 1.698 and low birefringence of 0.0025. The PSPHI exhibited high sensitivity of 25 mJ/cm² and high contrast of 8.4 when it was exposed to a 436 nm line (g-line), post-exposure baked at 130 °C for 2 min, and developed with an aqueous alkaline developer, 2.38 wt% tetramethylammonium hydroxide solution/10 wt% iso-propanol at 25 °C. A clear positive pattern of 4 μm line and space was obtained on a film exposed to 50 mJ/cm² of g-line by a contact printing method.

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A series of polyimides (PIs) / zincoxide (ZnO) nano-hybrid materials exhibiting high transparency, high refractive indices, and low wavelength dispersions were prepared by the in situ thermal decomposition method. First, the optical properties of six kinds of matrix PIs were investigated, and a fully aromatic PI derived from 4,4'-(hexafluoroisopropylidene) diphthalic dianhydride (6FDA) and 9,9-bis (4-aminophenyl) fluorene (BAFL) and a semi-aromatic PI derived from 3,3';4,4'-biphenyl tetracarboxylic dianhydride (BPDA) and 4,4'-diaminodicyclohexylmethane (DCHM) were chosen as transparent matrices. Secondly, two types of ZnO precursors, which are thermally decomposed into ZnO, were chosen, and the thermal decomposition behaviors of the ZnO precursors dissolved in PI films was examined by far-infrared (Far-IR) and variable temperature mid-infrared (IR) spectra. The PI/ZnO hybrid films prepared from Zn(NO₃)₂6H₂O as a ZnO precursor exhibit yellowish coloration, though the transparency of the hybrid films was significantly improved by using a preheated Zn(NO₃)₂6H₂O at 110 °C as a ZnO precursor or using a soluble PI solutions in place of poly(amic acid) solutions. The PI/ZnO hybrid films exhibited high thermal degradation temperatures, and 6FDA-BAFL and BPDA-DCHM/ZnO hybrid films exhibited higher refractive indices by up to +0.0037 (+0.25 %) and +0.0130 (+1.10 %), respectively, compared with the pristine PIs. In the case of BPDA-DCHM, the effect of hybridization with ZnO on the increase in the refractive index at infinite wavelength (n_∞) relative to the coefficient of wavelength dispersion (D) is more significant than that of modifying the chemical structures of PIs.

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This aim of this study was the conversion of indanthrone from its precursor, BOC-indanthrone, by acidolytic treatment in a photo-polymeric film. Because the high temperature and long thermal treatment time required for the deprotection of the BOC protective group may damage the application medium, acidolysis was employed to reduce the thermal treatment temperature and time in this study. Ultraviolet-visible (UV-vis) and Fourier-transform infrared (FTIR) spectroscopy showed that, in the presence of a photoacid generator (PAG), the conversion of BOC-indanthrone to indanthrone was achieved in the photopolymeric film at a low temperature and short thermal treatment time. Further, field-emission scanning electron microscopy (FESEM) and optical and polarized optical microscope (OM and POM) observations indicated that thermal treatment after acidolysis resulted in the formation of regenerated pigments, and they exhibited good dispersion in the photopolymeric film.

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A third class of polymer gel, termed a "slide-ring (topological)" gel, which is based on mobile cross-linker with a figure-of-eight structured dimer of cyclodextrin has been attracting numerous attentions; because of its remarkable physical properties such as large extensibility and mechanical strength. In this study, we applied atmospheric microplasma, based on microwave strip-line technology, to surface functionalization of a slide-ring gel to improve the surface hydrophilicity. When the gel surface was modified with microplasma in ambient air, the contact angle drastically changed into nearly 0° from the original angle of 46°. The x-ray photoelectron spectroscopy (XPS) after the treatment indicated 3.3 at.% atomic oxygen increase and 3.4 at.% atomic carbon decrease, respectively. These results suggest that the slide-ring gel surface is highly sensitive to the atmospheric microplasma and is functionalized promptly/effectively for biomimetic applications with less thermal damages even in ambient air.

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When the surface of ultra-high molecular weight polyethylene (UHMWPE) nonwoven fabric was treated with an oxygen plasma, the hydrophilic nature of the sample surface was improved. However, the sample was only colored slightly by in a dyeing test with dyestuffs done to investigate the effect of surface functionalization. A mixed-gas plasma treatment with fluorocarbon was able produce a sample that could be dyed a dark color using acid and reactive dyes. From the results of fourier transform infrared spectroscopy (FT-IR) and X-ray photoelectron spectroscopy (XPS) measurements, it was found that the carboxyl group increased on the sample surface as a result of the mixed-gas plasma treatment. As a simple evaluation method for investigating the effect of plasma treatment, the dyeing test was effective.

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Polytetrafluoroethylene (PTFE) sheet surface was treated by the diborane/H₂/He plasma for the deflurination to improve the painting performance. Diborane was generated by the H/He plasma treatment of a boron plate. And then, the defluorination plasma treatment with this diborane/H₂/He mixture gas performed to PTFE sheet. Fluorine atom content of treated PTFE surface was decreased to about one hundredth of that of untreated PTFE. The water contact angle of treated PTFE was also decreased from 12° to 50°. A paint coated on treated PTFE adhered to its surface strongly.

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To explore the low-temperature surface treatment of polymers using high-density atmospheric-pressure inductively coupled plasma (AP-ICP) microjet, the critical parameters determining the breakdown and sustainment of the pulse-modulated (PM) helium/argon (He/Ar) AP-ICP microjet were studied by varying the Ar flow rate, pulse-modulation frequency, f, VHF power, P, and duty ratio, DR. The AP-ICP microjet source used in this study consists of a planar serpentine-shaped antenna and an alumina discharge tube of 0.8 mm inner diameter. Although the minimum VHF power, P, required for the breakdown was 95 W for the pure helium plasma, it could be reduced to 51 W owing to the Penning effect by adding Ar (4-7 sccm) to He (3 slm). The lower limits of DR for the He/Ar PM plasma breakdown and sustainment were investigated by changing f at the constant P= 90 W. It was found that the minimum DR for the generation of the PM plasma without using the auxiliary ignitor was proportional to f. The linear relation indicates the existence of minimal on-time period that is presumably a requisite rise time of PM VHF voltage in the plasma circuit. The minimum DR for the breakdown became higher than that for the sustainment at f > 26 kHz, where the latter DR was 5-10 W. Consequently, it was found that the plasma operation with low net power is possible particularly under the low-f pulse modulation condition. Furthermore, a preliminary experiment on the surface treatment of polycarbonate by scanning the PM AP-ICP microjet under low-f conditions demonstrated the applicability of this plasma system to the surface processing of polymers without the thermal damage.

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The effect of surface-wave plasma pre- and post-treatment on immobilization of L-cysteine molecules onto molecules grafted polyurethane (PU) surface was studied using surface-wave plasma treatment. The polyethylene glycol (PEG) molecules are grafted onto PU surface by means of both pre-treatment and post-treatment of Ar plasma, which behaves to activate PU surface and crosslink PEG molecules to substrate. The XPS results showed the concentration of OH group making a covalent bond increased by the Ar plasma treatment and an amount of immobilized L-cysteine was almost linearly related to PEG molecules grafted onto PU surface.

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Water insoluble polyethylene glycol (PEG ) films as a core-shell of polymer powder were fabricated by the combination techniques of adsorption of PEG on the powder surfaces and atmospheric glow discharge(APGD) irradiation to the surface to take cross linking reaction of the adsorbed PEG. PEG 2000 was used as the precursor of the core-shell films. The obtained films on the powder surfaces were investigated by XPS,ATR-FTIR and wettability measurement using the capillary raise method.

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In this study, we examined the construction of biointerfaces on a commodity plastic surface using the non-equilibrium atmospheric pressure low frequency plasma (LF plasma) and poly(ethylene glycol) (PEG) macromonomers with different terminal functional groups. The surface of polypropylene (PP) was spin coated with poly(4-chloromethylstyrene) (PCMS) followed by PEG macromonomers and irradiated with LF plasma. The chemical immobilization of PEG proceeded rapidly and mostly completed within 30 s, which was confirmed from the contact angle measurements. It is interesting to note that the surface properties were remarkably different by the end group of PEG macromonomers used in this study. Monoacrylated PEG macromonomer-treated substrate exhibited high anti-biofouling property whereas dimethacrylated end PEG did not show anti-biofouling property. This method is simple and applicable for constructing PEG-based biointerface on a variety of commodity plastics.

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Poly(tetrafluoroethylene) (PTFE) plates grafted with N-isopropylacrylamide (NIPAAm) and 2-hydroxy-N-isopropylacrylamide (HIPAAm) as hydrophilic monomers have been prepared by the combined use of the oxygen plasma treatment and photografting. The investigation of the surface compositions of the grafted PTFE plates was analyzed by ESCA and thermo-responsive property was investigated by contact angle measurements toward water. Estimating the introduction of P(NIPAAm-co-HIPAAm) onto the PTFE surface, the polymer in the reaction vessel was followed by ¹H-NMR. ESCA spectra revealed the introduction of oxygen containing functional groups and PNIPAAm onto the PTFE plate. The phase transition temperature of the PTFE-g-P(NIPAAm-co-HIPAAm) rose with the ratio of PHIPAAm to PNIPAAm in the monomer solution. The temperatures for the ratio of PTFE-g-P(NIPAAm-co-HIPAAm) (N:H=70:30 and 50:50) were about 4°C and 55°C, respectively

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Surfaces of hydrophobic polymers were treated by atmospheric pressure plasma. The plasma system used was a newly developed damage-free dielectric barrier glow discharge. Ar was mainly used as a carrier gas. The treated polymer surfaces were mainly analyzed with contact angle measurement and X-ray photoelectron spectroscopy (XPS). In the treatment of high-density polyethylene (HDPE), atmospheric Ar plasma was found to alter the surface very hydrophilic, which is comparable to low-pressure O2 plasma. The addition of O2 in the plasma gas hardly improved the hydrophilicity. In the treatment of polytetrafluoroethylene (PTFE), atmospheric H2 (0.1%) plasma showed the greatest hydrophilicity but it was not as good as the treatment by low-pressure H2 plasma.

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