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We have developed a soft x-ray laser (SXRL) beamline equipped with an intensity monitor dedicated to ablation study such as surface processing and damage formation. The SXRL beam having a wavelength of 13.9 nm, pulse width of 7 ps, and pulse energy of around 200 nJ is generated from Ag plasma mediums using an oscillator-amplifier configuration. The SXRL beam is focused onto the sample surface by the Mo/Si multilayer coated spherical mirror. To get the correct irradiation energy/fluence, an intensity monitor composed of a Mo/Si multilayer beam splitter and an x-ray charge-coupled device camera has been installed in the beamline. The Mo/Si multilayer beam splitter has a large polarization dependence in the reflectivity around the incident angle of 45°. However, by evaluating the relationship between reflectivity and transmittance of the beam splitter appropriately, the irradiation energy onto the sample surface can be derived from the energy acquired by the intensity monitor. This SXRL beamline is available to not only the ablation phenomena but also the performance evaluation of soft x-ray optics and resists.

ABSTRACTAt present, there are few reports that have clarified the effectiveness of 23-valent pneumococcal polysaccharide vaccine (PPSV23) against all-cause pneumonia or pneumococcal pneumonia in community-acquired pneumonia (CAP) in older individuals in Japan. We conducted a hospital-based matched case-control study to investigate separately the preventive effects of PPSV23 and trivalent influenza vaccine (TIV) on all-cause CAP and pneumococcal CAP in older individuals in Japan. Cases were individuals aged 65 years or older who were newly diagnosed with CAP from October 2010 to September 2014. Two control patients with a different disease (one respiratory medicine and one non-respiratory medicine) matched for sex, age, date of outpatient visit, and medical institution were selected for each case. Odds ratios (ORs) and 95% confidence intervals (CIs) of PPSV23 and TIV for the occurrence of all-cause CAP and pneumococcal CAP were calculated using conditional and unconditional logistic regression models. The analysis included 161 cases and 308 controls from the 4-year period. The adjusted OR for the occurrence of all-cause CAP was 0.76 (95%CI = 0.44–1.32) with PPSV23 vaccination and 0.79 (95%CI = 0.50–1.25) with TIV vaccination compared with unvaccinated individuals. When the outcome index was restricted to pneumococcal CAP, the adjusted OR significantly decreased to 0.23 (95%CI = 0.08–0.66) with PPSV23 vaccination, but not with TIV vaccination (adjusted OR = 0.65, 95%CI = 0.31–1.36). PPSV23 vaccination is likely effective in reducing incidence of pneumococcal CAP in older individuals, although its preventive effect for all-cause CAP has not been achieved.

Objective.Cigarette smoking may be associated with increased risk of systemic lupus erythematosus (SLE), whereas the role of alcohol consumption is unknown. We examined the association between SLE risk and smoking or drinking.Methods.We investigated the relationship of smoking and drinking compared to SLE risk among 171 SLE cases and 492 healthy controls in female Japanese subjects. Unconditional logistic regression was used to compute OR and 95% CI, with adjustments for several covariates.Results.Compared with nonsmoking, current smoking was significantly associated with increased risk of SLE (OR 3.06, 95% CI 1.86–5.03). The higher the level of exposure to cigarette smoke, the higher the risk of SLE. Inhalation was also associated with increased SLE risk (OR 3.73, 95% CI 1.46–9.94 for moderate inhalation; OR 3.06, 95% CI 1.81–5.15 for deep inhalation). In contrast, light/moderate alcohol consumption had a protective effect on SLE risk (OR 0.38, 95% CI 0.19–0.76). As for beer, the risks for non-beer drinkers and beer drinkers were similar. This also applies to alcoholic beverages other than beer.Conclusion.Our results suggest that smoking was positively associated with increased SLE risk whereas light/moderate alcohol consumption was inversely associated with SLE risk, irrespective of the type of alcoholic beverage. Additional studies are warranted to confirm these findings.

We investigated the association between monovalent influenza A (H1N1) pdm09 (H1N1pdm) vaccine and pneumonia in elderly people. Study design was a hospital-based, matched case-control study. Cases comprised patients ≥65 years old who had been newly diagnosed with pneumonia. For each case, 2 controls were defined as individuals with other diseases (not pneumonia) who were matched by sex, age, entry date, and the visited hospital. Study period was the interval from 1 September 2009 until 30 September 2010. Because a pandemic of influenza A (H1N1) occurred during study period, we analyzed selected subjects who had enrolled during the influenza A (H1N1) pandemic. We calculated the odds ratios (ORs) and 95% confidence intervals (CIs) for pneumonia in H1N1pdm-vaccinated subjects compared with unvaccinated subjects using a conditional logistic regression model to assess the association between H1N1pdm vaccine and pneumonia. The subjects during the period of the influenza A (H1N1) pandemic were 20 cases and 40 controls. Subjects who had received H1N1pdm vaccine showed a significantly decreased OR for pneumonia (OR = 0.10, 95% CI = 0.01–0.98) compared with unvaccinated subjects. In conclusion, H1N1pdm vaccination may have prevented pneumonia among the elderly during the 2009–2010 influenza A (H1N1) pandemic in Japan.

In this letter we discuss the energy dissipation of short-lived para-positronium (p-Ps) in polymers and silica glass. The Sparameter characterizing the Doppler broadening of p-Ps annihilation is determined from the previously reported systematic data of positron annihilation age momentum correlation for various polymers and silica glass. A comparison of the Sparameter with that expected for thermalized p-Ps trapped in a free volume reveals that p-Ps is not thermalized and possesses excess energy in fluorinated polymers and silica glass, indicating that it is difficult for Ps to lose energy in substances containing heavy elements such as fluorine and silicon.

Micro- and nano-scale fabrications of various fluorinated polymers were demonstrated by direct maskless etching using a focused ion beam (FIB). The etching rates of perfluorinated polymers, such as poly(tetrafluoroethylene) (PTFE), poly(tetrafluoroethylene-co-hexafluoropropylene) (FEP), poly(tetrafluoroethylene-co-perfluoroalkoxyvinylether) (PFA), were about 500--1000 times higher than those of partially fluorinated polymers, such as poly(tetrafluoroethylene-co-ethylene) (ETFE) and poly(vinilydene--fluoride) (PVdF). Controlled high quality and high aspect-ratio nanostructures of spin-coated cross-linked PTFE were obtained without solid debris. The height and diameter of the fibers were about 1.5 \mbox{$\mu$m} and 90 nm, respectively. Their aspect ratio was about 17.

OBJECTIVE: Recent studies have identified signal transducer and activator of transcription 4 (STAT4) as a susceptibility gene for systemic lupus erythematosus (SLE) in different populations. Similarly, tumor necrosis factor receptor superfamily, member 1B (TNFRSF1B) has been reported to be associated with SLE risk in Japanese populations. Along with environmental factors such as smoking, both polymorphisms may modulate an individual’s susceptibility to SLE. We investigated these relationships in a case-control study to evaluate risk factors for SLE among Japanese women. METHODS: We investigated the relationship of the STAT4 rs7574865 and TNFRSF1B rs1061622 polymorphisms to SLE risk with special reference to their combination and interaction with cigarette smoking among 152 SLE cases and 427 controls. RESULTS: The TT genotype of STAT4 rs7574865 was significantly associated with increased risk of SLE (OR 2.21, 95% CI 1.10–4.68). Subjects with at least one G allele of TNFRSF1B rs1061622 had an increased risk of SLE (OR 1.56, 95% CI 0.99–2.47). The attributable proportion due to the interaction between the TNFRSF1B rs1061622 genotypes and smoking was estimated to be 0.49 (95% CI 0.07–0.92), indicating that 49% of the excess risk for SLE in smokers with at least one G allele was due to an additive interaction. A lack of significant associations of STAT4 with smoking was observed. No significant gene-gene interactions were found among polymorphisms of STAT4 and TNFRSF1B. CONCLUSION: Our findings suggest that the association between cigarette smoking and SLE could be differentiated by the TNFRSF1B rs1061622 T allele among female Japanese subjects. This preliminary exploratory result should be confirmed in a larger study.

Polymer electrolyte fuel cell (PEFC) membranes based on crosslinked tetrafluoroethylene‐co‐hexafluoropropylene (FEP) have been fabricated by pre‐irradiation grafting method. The chemical structures of crosslinked materials have been analyzed by Differential Scanning Calorimeter (DSC) and 19F solid‐state Nuclear Magnetic Resonance (NMR) spectroscopy. The radical yields of irradiated samples were measued by Electron Spin Resonance (ESR), and the mechanism of grafting reaction has been discussed. The styrene grafted materials were sulfonated by chlorosulfonic acid. The ion exchange capacity of the obtained sulfonated crosslinked FEP (S‐FEP‐X) showed 2.0 to 2.4 meq/g, which were 2.2 to 2.7 times higher than that of Nafion®112. Glass transition temperatures (Tg) of S‐FEP‐X were almost independent on crosslinking dose of FEP, and show about 96 °C, which are slightly higher than that of Nafion®. The electrochemical properties of the membranes have been measured, and cell performances of them have been evaluated. Ionic conductivities (ICs) of S‐FEP‐X are 1.2 to 1.6 times higher than that of Nafion®. The higher network densities gave the higher open circuit voltage (OCV). The power density of S‐FEP‐600kGy was about 10% higher than that of Nafion® at 500mA/cm2. Thus, the obtained sulfonated membranes can be expected to apply for high efficiency PEFC.

Ion exchange membranes (IEMs) were prepared by preirradiation induced grafting of styrene with or without divinylbenzene (DVB) into crosslinked polytetrafluoroethylene (RX‐PTFE) films and successively sulfonated by chlorosulfonic acid. The effects of the DVB concentration and solvent on the kinetic of the graft polymerization were studied. The ion exchange capacity (IEC) values of the prepared membranes ranging from 1.5 to 2.8 mequiv/g were obtained. The degree of swelling increased with the increase in the degree of grafting, while higher crosslinking density of both the RX‐PTFE matrices and the grafts suppressed the degree of swelling. The chemical stabilities of the IEMs were tested by recording the weight of the membranes being soaked in hot H2O2 solutions. The weight‐time curves of the prepared membranes showed one‐step quick decrease due to the decomposition of the poly(styrene‐sulfonic acid) (PSSA) grafts. Higher crosslinking density in both the RX‐PTFE matrices and the grafts improved the chemical stability of the IEMs. The ionic conductivity of the IEMs increases with the increase in the IEC values. The IEMs with IEC values higher than 2.2 mequiv/g hold the higher ionic conductivity than that of Nafion® 112 membrane. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 101: 3587–3599, 2006

The relation between dietary habits and the risk of ossification of the posterior longitudinal ligaments of the spine (OPLL) was investigated in a case-control study conducted in Japan from 1998 to 2001. Prevalent OPLL cases ( n = 69) were identified and individually matched by age and sex with community controls ( n = 138) randomly selected from the general population in Hokkaido. A self-administered food-frequency questionnaire was used to assess habitual dietary intake. The odds ratio (OR) and its 95% confidence interval (CI) were estimated, using conditional logistic regression models to compute the OR adjusted for a history of diabetes mellitus. We found that frequent consumption of pickles (salted products) was significantly associated with an increased risk of OPLL, with an adjusted OR of 1.6 (95% CI, 1.1 to 2.2). The adjusted OR for nondaily consumers of rice was 3.0 (95% CI, 2.4 to 3.7). Frequent consumption of chicken (adjusted OR, 0.5; 95% CI, 0.3 to 0.98) and soy foods (adjusted OR, 0.4; 95% CI, 0.2 to 0.7) was significantly associated with a decreased risk of OPLL. Our findings suggest that dietary habits may constitute independent risk factors for OPLL. Further studies will be needed to prospectively determine the relationship between dietary habits and OPLL risk.

The purpose of this study was to examine whether a high serum concentration of phytoestrogens reduces the risk of prostate cancer in a case‐control study nested in a community‐based cohort in Japan (Japan Collaborative Cohort (JACC) Study). Information on lifestyles and sera of the subjects were collected in 1988–90, and they were followed up to 1999. Incident and dead cases of prostate cancer and controls were matched for study area and age. Phytoestrogens and sex hormones in sera stored at −80°C were measured in 2002. Of 14,105 male subjects of the cohort who donated their sera, 52 cases and 151 controls were identified. Three datasets were analyzed; 1) all subjects, 2) 40 cases and 101 controls after excluding subjects with low testosterone levels who were suspected of having had medical intervention, and 3) 28 cases and 69 controls with prostate specific antigen level of ∼10.0 ng/ml. The odds ratio (OR) for the highest level to the lowest was 0.38 (95% confidence interval (CI); 0.13, 1.13) for genistein, 0.41 (0.15, 1.11) for daidzein, and 0.34 (0.11, 1.10) for equol for the second dataset. Genistein and daidzein showed similar findings in the third one. Equol and equol/daidzein ratio showed consistent findings in all three datasets (OR=0.39, 95% CI; 0.13, 0.89, trend P=0.02 for the first dataset). Their effects seemed to be independent of serum sex hormones. In conclusion, serum genistein, daidzein, and equol seemed to dose‐dependently reduce prostate cancer risk. (Cancer Sci 2004; 95: 65–71)

Micromachining of crosslinked PTFE (polytetrafluoroethylene) using synchrotron radiation direct photo‐etching method has been demonstrated. High aspect‐ratio microfabrication was carried out. The etching rate of crosslinked PTFE was higher than that of non‐crosslinked PTFE. Through the etching rate measurements of various samples, it was found that synchrotron radiation etching rate of crosslinked PTFE only depends on the degree of crosslinking, neither molecular weight nor crystallinity. The effect of molecular motion on etching process was discussed from temperature dependence data on etching rate. Furthermore, the surface region of synchrotron radiation irradiated sample was investigated by Fourier transform infrared spectroscopy and the experimental result showed that the modification induced by synchrotron radiation proceeded before desorption.

Summary: The rate constants for intramolecular excimer formation, kDM, of poly(α-methylstyrene) with different molecular weight were determined by using picosecond pulse radiolysis. Values of kDM for poly(α-methylstyrene) are a little smaller than those for polystyrene with nearly same molecular weight. It appears to be mainly due to steric hindrance by methyl substituent of main chain.

Abstract Despite a rapid increase in disabled elderly in Japan, the burden of the caregiver has not been properly assessed due to a lack of objective measurements. Our study was aimed at adapting and validating the Zarit Caregiver Burden Interview (ZBI) in Japan, which is one of the most widely used measurements for caregivers' burden in the United States. Sixty‐six caregivers answered the self‐administered questionnaire, involving the Japanese version of the ZBI and questions regarding their caregiving situation. Our study demonstrated that the Japanese version of the ZBI had equally as high reliability and validity as the original version. The Japanese ZBI had a high test—retest reliability (r = 0.76) and internal consistency (Cronbach's alpha = 0.93). The total score of the ZBI was highly correlated with the caregivers' score of the Center for Epidemiologic Studies Depression Scale (CES‐D) score (r = 0.50), as well as a single global rating of burden (r = 0.71). It was also shown that demographic distribution of the score of the Japanese version had a similar trend to that of the original version. Caregivers who looked after patients with behavioral disturbances were found to have a significantly higher ZBI score than those who looked alter patients without behavioral disturbances, which is consistent with previous findings. It is concluded that the Japanese version of the ZBI can be used to measure feelings of burden of caregivers in the Japanese population and can be used for cross‐cultural comparison.

The formation processes of two distinct excimers of poly(N-vinylcarbazole)(PVCZ) have been directly observed by using a picosecond single-pulse radiolysis system with 10 ps time resolution. The primary processes of radiation-induced excitation in the polymer solutions have been studied. A so-called second excimer (λmaxof fluorescence = 375 nm) of PVCZ is almost completely formed immediately after a 10 ps electron pulse. Most of the sandwich-type excimer (λmaxof fluorescence = 420 nm) is formed in several nanoseconds. Most of the second excimer was confirmed to be formed directly in preexisting sites. Most of the sandwich-type excimer was confirmed to be formed through structural change of the excited carbazolyl and the ground-state carbazolyl chromophore to the sandwich conformation. Both the concentration of the preexisting trap sites and the efficiency of energy migration along the polymer chain before relaxation or solvation of the excited state are considered to be most important in the formation of the second excimer. Most of the primary excited states of PVCZ in irradiated toluene solutions of PVCZ are formed immediately after the 10 ps electron pulse. These very fast formation processes of excited states of solute molecules agree with the recent experimental results observed in irradiated hydrocarbon solutions of aromatic molecules in the picosecond time domain.

Formation processes of poly(N-vinylcarbazole) cation (PVCZ+) and its reactivity were studied by a pulse radiolysis technique. In the formation of PVCZ+, the charge transfer from a solvent or additive cation radical plays an important role. Once formed, the PVCZ+is stabilized. This stabilization makes the ion recombination reaction rate smaller by a factor of about 5 compared with the monomer cation. The cation scavenging reaction is also affected by this stabilization, and PVCZ+is only scavenged by certain compounds of appreciably low ionization potential (for example; N,N,N',N'-tetramethylbenzidine). The rate constant for the scavenging reaction was estimated to be about 3×109M-1s-1.

The prognosis of atrophic hypothyroidism with blocking type TSH-binding inhibitor immunoglobulin was studied. Among 45 patients (16 males and 29 females) with overt hypothyroidism (serum TSH >40 mU/l) without goitre, thyroid autoantibody to microsomal antigen was positive in 38 or 84.4%, and 4 or 8.9% had TSH-binding inhibitor immunoglobulin, which was shown to be a TSH-stimulation blocking antibody by cAMP production assay using cultured porcine thyroid cells. Thyroidal radioactive iodine uptake was low and thyroid hormone replacement therapy was required. Long-term follow up of 2 patients with strongly positive TSH-binding inhibitor immunoglobulin for 2 to 7 years, however, revealed recovery of the thyroid function after steroid therapy or spontaneously with iodide restriction, respectively, correlating with decrease in both TSH-binding inhibitor immunoglobulin and TSH-stimulation blocking antibody activities. Thyroidal radioactive iodine uptake became normal and histological examination of the thyroid in one patient revealed well-preserved thyroid follicles with lymphocytic infiltration. Recovery of thyroid function can be expected with a decrease in TSH-binding inhibitor immunoglobulin activity in atrophic hypothyroidism, which is not necessarily the end stage of chronic thyroiditis.

A photocathode with a high quantum efficiency (Q.E.) and long lifetime can be fabricated by evaporating a protective layer onto a high Q.E. semiconductor photocathode. In this study we tried to improve the stability and lifetime of a Cs-Te photocathode by coating a CsBr protective layer of 20 nm in thickness over the surface. After the protective layer was applied, we measured the Q.E. of the photocathode and the lifetime in the evaporation chamber. The Q.E. of the coated Cs-Te was confirmed to be about 0.80% and to remain unchanged for a period of longer than 25 d. The effectiveness of the protective layer against exposure of the Cs-Te photocathode to oxygen gas was also confirmed for the first time. Our experiments were the first to show a lifetime improvement of a photocathode installed inside an rf gun compared to the same type of photocathode with no protective coating.

We generated low-flux X-ray micro-planar beams (MPBs) using a laboratory-scale industrial X-ray generator (60 kV/20 mA) with custom-made collimators with three different peak/pitch widths (50/200 μm, 100/400 μm, 50/400 μm). To evaluate normal skin reactions, the thighs of C3H/HeN mice were exposed to 100 and 200 Gy MPBs in comparison with broad beams (20, 30, 40, 50, 60 Gy). Antitumor effects of MPBs were evaluated in C3H/HeN mice with subcutaneous tumors (SCCVII). After the tumors were irradiated with 100 and 200 Gy MPBs and 20 and 30 Gy broad beams, the tumor sizes were measured and survival analyses were performed. In addition, the tumors were excised and immunohistochemically examined to detect γ-H2AX, ki67 and CD34. It was shown that antitumor effects of 200 Gy MPBs at 50/200 μm and 100/400 μm were significantly greater than those of 20 Gy broad beams, and were comparable with 30 Gy broad beams. γ-H2AX-positive cells demonstrated clear stripe-patterns after MPB irradiation; the pattern gradually faded and intermixed over 24 h. The chronological changes in ki67 positivity did not differ between MPBs and broad beams, whereas the CD34-positive area decreased significantly more in MPBs than in broad beams. In addition, it was shown that skin injury after MPB irradiation was significantly milder when compared with broad-beam irradiation at equivalent doses for achieving the same tumor control effect. Bystander effect and tumor vessel injury may be the mechanism contributing to the efficacy of MPBs.

A chlorinated resist named ZEP changes from positive- to negative-tone with a high dose of electron beam irradiation. The sensitivities to a 100-kV electron beam as a dual positive- and negative-tone resist are evaluated with various developers. Although the positive-tone sensitivity varies with different developers owing to different solvation strengths, the threshold dose for the positive-negative (P-N) inversion is independent of the developer. According to an analysis using X-ray photoelectron spectroscopy and NMR spectroscopy, the amount of chlorine atoms and terminal double bonds generated by chain scission determines the scission/crosslinking probabilities, i.e., the threshold of the P-N inversion.

ZEP520A (1:1 copolymer of ?-chloromethacrylate and ?-methylstyrene, ZEON) is a main-chain scission-type positive-tone resist used for electron beam (EB) lithography and is known for its high sensitivity and high resolution. In this study, ZEP520A was irradiated using a 100 kV EB, and the decomposition mechanisms were analyzed by gel permeation chromatography, Fourier transform IR spectroscopy, NMR spectroscopy, and pulse radiolysis. Chlorines were confirmed to easily dissociate as Cl-ions (dissociative electron attachment, DEA) and ZEP520A underwent ?-scission. Multiple channels could be considered for the main-chain scission, including DEA and the charge transfer complex between phenyl radical cations and Cl-ions.

Electron beam nanoimprint lithography was proposed for fabricating the micro-/nanostructures of cross-linked poly(L-lactic acid) (RX-PLLA). PLLA with triallyl isocyanurate (TAIC) solutions were dropped on the Si-molds fabricated by the conventional EB lithography technique. PLLA/TAIC on Si-molds were imprinted and cross-linked with doses from 10 to 500 kGy at room temperature under vacuum. The micro-/nanostructures of RX-PLLA were successfully obtained with high accuracy. Hence, it was found that the imprinted structures of RX-PLLA (100 kGy irradiation) show low line edge roughness and high thermal durability at 120 °C.

Electron beam nanoimprint lithography was proposed for fabricating the micro-/nanostructures of cross-linked poly(L-lactic acid) (RX-PLLA). PLLA with triallyl isocyanurate (TAIC) solutions were dropped on the Si-molds fabricated by the conventional EB lithography technique. PLLA/TAIC on Si-molds were imprinted and cross-linked with doses from 10 to 500 kGy at room temperature under vacuum. The micro-/nanostructures of RX-PLLA were successfully obtained with high accuracy. Hence, it was found that the imprinted structures of RX-PLLA (100 kGy irradiation) show low line edge roughness and high thermal durability at 120 degC.

The chlorinated resist materials ZEP520A and ZEP7000 (ZEON Co.) are changed from positive-tone to negative-tone by high dose electron beam (EB) and ion beam irradiation. Here, the reaction mechanisms of the positive-negative inversion induced by EB were attempted to be clarified with ultraviolet-visible (UV-vis) spectroscopy and X-ray photoelectron spectroscopy. The results indicated that dissociative electron attachment would be induced in response to the irradiation dose. For high dose irradiation (>5 mC cm-2), it was suggested that crosslinking would become predominant because of the structural changes in the resists and the lower scission ratio due to the decrease of the chlorine.

The chlorinated resist materials ZEP520A and ZEP7000 (ZEON Co.) are changed from positive-tone to negative-tone by high dose electron beam (EB) and ion beam irradiation. Here, the reaction mechanisms of the positive-negative inversion induced by EB were attempted to be clarified with ultraviolet-visible (UV-vis) spectroscopy and X-ray photoelectron spectroscopy. The results indicated that dissociative electron attachment would be induced in response to the irradiation dose. For high dose irradiation (>5 mC cm-2), it was suggested that crosslinking would become predominant because of the structural changes in the resists and the lower scission ratio due to the decrease of the chlorine.

The increasing density of semiconductor devices has required the development of high resolution exposure techniques. The miniaturization of feature sizes has been achieved mainly by shortening the exposure wavelength. Extreme ultraviolet (EUV) lithography at 13.5 nm exposure wavelength will be introduced into pilot lines in 2011, and high volume manufacturing is expected to be started in 2013/2014. Furthermore, the possibility of extending EUV lithography down to sub 5 nm has been proposed as next-generation lithography, by reducing the exposure wavelength to 6.x nm. ASML has estimated the throughput of exposure system for 6.x nm EUV lithography is comparable with 13.5 nm lithography, based on the experiments such as reflective multilayer optics. However, the estimation has not included the sensitivities of resist materials, which is one of the most important criteria for the practical lithography systems. Here, the sensitivities of several kinds of typical resists in EUV/soft X-ray wavelength down to 3.1 nm were actually evaluated by experiments. The sensitivities of resist materials were roughly proportional to the absorbed dose calculated by line absorption coefficients of resists. The dependence of the exposure wavelength on EUV resist sensitivity could be theoretically predicted for the next-generation lithography, if sensitivity at a certain EUV wavelength like 13.5 nm is experimentally obtained.

Characteristics of the picosecond Cerenkov light pulse generated from fused silica in a shape of cone and from water in a conical vessel have been investigated in the wavelength range from 230 nm to 500 nm. The pulse durations are estimated to be 27.0±4.0 ps for fused silica and 30.0±7.0 ps for water. It is shown that the present Cerenkov light pulse can be used for measuring the luminescent decay time in the picosecond range in conventional materials such as PPO and Tl+monomers in KI crystals at room temperature.