It is described that p-chlorophenylacetylene, (p-CPA) monomer could be polymerized by γ-ray irradiation in the solid sate at 0°C and its resulting poly(p-CPA), P(p-CPA) polymer was characterized with UV, laser Raman, and ESR spectroscopic methods by comparison with the their data of the P(p-CPA) polymer synthesized by the Rh complex as the highly stereoregular polymerization catalyst. It was found, interestingly, that the P(p-CPA) polymer produced by γ-ray irradiation of the monomer has the trans form as the major structure with respect to the main chain while the polymer catalytically polymerized with the Rh catalyst has the cis-transoidal structure. It was found that the thermal treatment of P(p-CPA) polymer catalyzed with the Rh complex induced the isomerization from cis form to trans one where a large amount of radical spins was generated, breaking the conjugated double bond. Based on data of the radical concentration of the thermal treated polymer and topochemically polymerized polymer it was concluded that the both polymers have the trans structures and work as the radical stabilizers.

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A series of styrene-isoprene copolymers (SI copolymers) have been synthesized from styrene and isoprene. The styrene- isoprene cyclized copolymers (SI cyclized copolymers) have been synthesized by proper cyclization of the obtained copolymers. Through the regulation of ether additives, the copolymers contain different 1, 4-copolymer content and 3, 4-copolymer content. The relative content of 3, 4-copolymer and 1, 4-copolymer in SI copolymers is calculated by data of IR and ¹H NMR spectra and the cyclization process is monitored by IR spectra. In this paper, we discuss the influence of various factors on the copolymerization, the cyclization and the products in detail. The minimum quantity of exposure energy required E_min of the phatoresists prepared by SI cyclized copolymers is about 9.7mJ/cm². The resistance of the photoresist to acids and plasma etching is better than that of cyclized polyisoprene photoresist.

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In this work, a series of nitrone compounds have been synthesized. Some nitrones synthesized only have substituents on the phenyl rings connected with α-carbons, and the others are substituted on both phenyl rings, The obtained results indicate that for the former kind of nitrones, no matter what substituents are, either electron acceptor or electron donnor, the photocyclization is accelerated However, for the later kind, due to the formation of push-pull structure along the main frame of nitrone, the reaction rate decreases drastically. The results mentioned above are discussed preliminarily.

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We report on the evaluation of the catalytic acid behavior in chemically amplified resists, which was carried out using an interdigitated array electrode (IDA). When direct current is applied to resist films during the post-exposure baking process, the resist sensitivity decreases near the edge of the cathode on the IDA. This phenomenon is basically common to the several types of chemically amplified resists used in this work. It is considered that catalytic protons generated during exposure reduce, becoming electrically neutral on the cathode surface and losing their catalytic ability for chemical amplification reactions. Reduction causes a concentration gradient and the diffusional transport of protons. There is a semicircular cavity in a cross-sectional-developed pattern of chemically amplified negative type resists. From the size of the cavity, the acid diffusion coefficient in SAL601(Shipley Co.) resist can be roughly estimated to be 70nm²/s at 100°C.

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The characteristics of a chemically amplified silicone-based negative resist, composed of alkali-soluble silicone polymer and an acid generator, have been studied. This polymer is obtained through a sol-gel reaction of a mixture of phenyltrimethoxysilane and 2-(3, 4-epoxycyclohexyl)ethyl trimethoxysilane and has numerous silanol groups that make it alkali-soluble. The resist's chemistry is based on the acid-catalyzed condensation of the silanol groups during post exposure baking. The CSNR includes silicon atoms in such abundance that it exhibits high resistance to oxygen reactive ion etching and can be used as a top imaging layer of a two-layer resist system. Using a KrF excimer laser stepper, 0.25-μm lines-and-spaces patterns can be fabricated with a two-layer resist system. The sensitivity depends on the structures of acid generators (AG's). A resist with triphenylsulfonium triflate showed the highest sensitivity in this study.

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We describe a new electron beam (EB) direct wafer writing process using a bi-level resist system of three-dimensional polysilphenylenesiloxane (TSPS) over a conductive bottom layer. The top-layer TSPS chemically amplified negative resist, developed with alkali, is highly sensitive and has high contrast. The conductive bottom layer comprises tetracyanoquinodimethane (TCNQ) complex salt, binder resin, crosslinker, and photoacid generator; it has excellent conductivity and stability with the developer used for the TSPS. We achieved high resolution with a high aspect ratio and significantly reduced pattern distortion caused by EB charging.

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Pyrenylmethyl group-containing phosphonium salts (1 and 2) were prepared and their ability as photolatent cationic initiator was examined in the polymerization of epoxides and vinyl monomers. Photopolymerization of reactive epoxides such as cyclohexene oxide (CHO) and styrene oxide (SO) proceeded very well, but some clear termination was observed in the polymerization of less reactive epoxides. In the photopolymerization of vinyl monomers such as vinyl ethers and styrenes, no termination was observed. Re-initiation mechanism, which involved photodecomposition of the phosphine-terminated end of polystyrene to produce a new cationic initiation species, was suggested by the photopolymerization of CHO with benzyl triphenylphosphonium salt as model of the terminated end.

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The kinetic parameters and the changes in polymer coil dimensions during the competitive intra- and intermolecular photocrosslinking reactions in THF solution depend on the number of alkyl substituents in the diamine component and the amount of benzoph- enonetetracarboxylic dianhydride(BTDA) in polyimide. When a second orth-alkyl substituent is introduced, the quantum yield for intramolecular reaction, including some side reaction with solvent increases and oppositely the quantum yield for intermolecular reaction decreases. The magnitude of <s²>^1/2 and M_w is related to the degree of the competition between intra- and intermolecular crosslinking. The contraction ratio, g, of polymer coils decreases smaller as the amount of BTDA in the polyimide increases.

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We developed a new radiation indicator ink for screen printing, which allows simple assessment of absorbed doses of radiation employed for various purposes (e.g., γ-rays used for the sterilization of medical supplies, and electron beams for industrial use). This indicator is prepared by coating the packing paper with an indicator ink made primarily of diethylaminoazobenzene. When this indicator is irradiated with γ-rays at a dose rate of 23.0kGy/h, the color of the indicator changes in proportion to the absorbed dose, and this change is highly reproducible. The indicator's color is yellow before irradiation, and it changes to orange at an absorbed dose of 10kGy, to red at 25kGy (the dose level used for sterilization), and to purplish red at 50kGy. Within a dose rate range of 0.52-42.1kGy/h, the color changes in proportion to absorbed doses only, independent of the dose rate. The dose-response curve of the indicator when exposed to electron beam irradiation generated by a linear electron accelerator was identical to the response curve when the indicator was exposed to γ-ray irradiation. In addition to the composition of this indicator ink, the composition of a label indicator and a photogravure ink, which the authors reported in previous papers, will also be presented in this paper.

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The excited triplet state of carbazole chromophores in Langmuir-Blodgett (LB) films for carbazole containing polymers, i.e., copolymers (P(C-iB)) of 2-(9- carbazolyl)ethyl methacrylate (CzEMA) with isobutyl methacrylate (iBMA) and a copolymer (P(C-OD)) of CzEMA with octadecyl methacrylate (ODMA), was investigated. In the case of P(C-iB), an interlayer interaction plays a role when more than four layers of chromophoric layers are deposited. It was confirmed that triplet energy migration between triplet chromophores mainly depends on the interchromophore distance, whether the system consists of 2-dimensional LB film or 3-dimensional amorphous polymer film.

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The relationship between the decomposition behaviors of the photodegradable polyesters such as polyethylene terephthalate and polyacetic acid and their molecular structures were studied to explain photode- gradability of the polyesters. In the Norrish-type photodecomposition, the rate of mainchain scission of a polyester depends on its monomer structure. The UV absorption wave lengthes of the carbonyl group in each polyester are considered as playing an important role in the photodecomposition of, the polyesters.

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To quantitatively evaluate the extent of non-site-selective excitation in photochemical hole-burning (PHB), we measured the extent of laser- induced hole hilling (LIHF) at 20K in sulfonated tetraphenylporphine (TPPS) doped into polyvinyl alcohol (PVA) and sulfonated mesoporphyrin (MPS) doped into PVA. The difference between the extent of UHF for TPPS/PVA and MPS/PVA is attributed to the four phenyl groups in the TPPS molecule. For TPPS/PVA, the value of the Debye- Waller factor (one of the parameters describing non-site-selective excitations) derived by analyzing the extent of LIHF was 0.81±0.17 (x± SD). This value is same as the value determined in other study by measuring photon echo at 20K.

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Polymer films of tetrahydrofuran containing 4, 4′-bipyridinium-tetrakis[3, 5- bis(trifluoromethyl)phenyl]borate as part of the main chain were cast on the surface of an optical waveguide (OWG) glass and were irradiated in degassed atmosphere. Colour changes due to photoinduced electron transfer in ultra-thin polymer films were sensitively detected by the OWG technique.

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Until quite recently it was believed that dissolution inhibition in phenolic resins is based on a general hydrophobic effect of the inhibitor. Honda et al. [5] have now shown that the hydrophobicity of an additive is not sufficient and that the polar functional groups of the inhibitor play an important role in the inhibition effect. They found that additives with very similar skeletal structures, and therefore with similar hydrophobicity, but which differ in their polar functional groups, have very different inhibition efficiencies in a common novolak resin. In an earlier communication [4] it was suggested that inhibition in phenolic resins comes about by the blocking of some of the hydrophilic OH-groups. Such blocking action by the inhibitor presupposes interaction between the inhibitor and the phenols of the resin. Here we investigate this interaction by determining the associated equilibrium constants in dilute solution. From these data the fraction of phenol-bound inhibitors in the casting solutions of the films can be estimated. For the group of additives investigated by Honda et al. [5] the fraction of phenol-bound inhibitors correlates quite satisfactorily with the inhibition effect.

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This paper assesses the progress of Step and Scan systems towards "Production 250nm Lithography". Advantages of the Step and Scan technique are discussed.
The relationships between NA, wavelength, resolution, and depth of focus are examined. The lithographic performance of the new generation Deep-UV Step and Scan system with high-NA optics is presented. Data is provided from electrical probe linewidth metrology and SEM analysis. Linewidth control of 27nm (3 sigma) is demonstrated over a large field size of 650mm² for 350nm features. A 250nm resolution capability is shown.
The family of Step and Scan systems, I-Line--Deep-UV--Very- Deep-UV, is reviewed in the context of progress towards 250nm lithography . The impact of Phase Shift Masks is highlighted . Particular attention is paid to the effect of partial coherence on the depth of focus achievable with Phase Shift Masks. Examples of 250nm lithography in a single level resist system are presented . It is indicated that optical lithography will continue to be the dominant lithographic technique down to sub-250nm lithography and that Step and Scan technique will be a critical factor in maintaining this dominance.

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OPS-Polyimides (OPS-PI), which are compoesd of a series of thiophenylene moieties, -(C₆H₄S)_n- oligo-p-phenylene sulfide (OPS), and imide groups, have been designed on the base of our proposed photoconduction mechanism and showed a high sensitivity. OPS-PI consist of two different functional groups. An imide gruop in OPS-PI generates carriers by absorbing the visible light. And carriers are transported in the paths formed by OPS segments. Carrier transport mechanism will be discussed on the band-conduction model. The sensitizing in the near infrared region by H₂Pc doping is proposed on the base of the energy diagram. The application of OPS-PI to xerographic photoreceptors is shown including doped OPS-PIs.

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