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A metrological definition and a target value for linewidth roughness (LWR) in a gate pattern of MOSFETS are proposed. The effects of sampling interval gate-LWR measurements by critical-dimension scanning electron microscopy on measurement accuracy were examined by both experiment and simulation. It was found that a 10-nm interval is sufficiently small to fully characterize roughness in a typically chosen 2-[micro]m-long line. Random image noise and intrinsic LWR variations are found to have larger effects on the measured LWR value than the finiteness of the sampling interval. A practical procedure for improving the measurement accuracy is also devised. Moreover, a methodology for establishing the gate-LWR target is proposed. Threshold-voltage shift caused by gate-LWR is determined from the LWR spectrum and the I-V curves of a transistor without LWR (i.e., ideal I-V curves). Index Terms--Line-edge roughness (LER), linewidth roughness (LWR), MOSFET.

Polyamines are aliphatic hydrocarbons with terminal amino groups and are essential for biological activities. It has been reported that polyamines have health-promoting effects in animals, such as the extension of lifespan by polyamine intake. The identification of a high polyamine-producing bacterium from foods could lead to the development of a novel probiotic candidate. We aimed to identify high polyamine-producing bacteria from food, and isolated and collected bacteria from vegetables and fermented foods produced in Japan. We successfully acquired Latilactobacillus curvatus KP 3-4 isolated from Kabura-zushi as a putrescine producing lactic acid bacteria. Comparing the polyamine synthesis capability of L. curvatus KP 3-4 with that of typical probiotic lactic acid bacteria and L. curvatus strains available from the Japan Collection of Microorganisms, it was found that only L. curvatus KP 3-4 was capable of exporting high levels of putrescine into the culture supernatant. The enhancement of putrescine production by the addition of ornithine, and whole-genome analysis of L. curvatus KP 3-4, suggest that putrescine is synthesized via ornithine decarboxylase. The administration of L. curvatus KP 3-4 to germ-free mice increased the concentration of putrescine in the feces. [ABSTRACT FROM AUTHOR]

The article presents chemical equations related to the article "Activation of Marginally Reactive Boron Enolates by MeLi for the Formation of Enol Phosphates and Synthesis of the Δ9-THC Intermediate" by Hiroki Kawada and others, published in "Journal of Organic Chemistry" in 2015.

A mechanism of the photoresist shrinkage induced by electron-beam (EB) irradiation was studied in detail. A precise cross-sectional profile of a photoresist pattern is obtained by a scanning transmission electron microscope (STEM) after HfO2 atomic layer deposition on a sample. Photoresist lines and spaces formed on either of bottom anti-reflective coating (BARC) layer or spin-on-glass (SOG) layer were exposed to EB at a much higher dose than a practical dose (to accelerate shrinkage intentionally). The obtained STEM images of the patterns before and after EB irradiation showed that EB irradiation causes necking of the pattern profile as well as linewidth slimming. In addition, it was suggested that the BARC layer shrinkage results in the elastic deformation of the pattern profile, whereas the SOG layer does not shrink. Furthermore, EB irradiation only to the lines or spaces was performed. The EB irradiation to spaces caused sidewall shrinkage and necking of the pattern profile, although no electron was irradiated directly into the pattern. This result is considered to be due to the electrons scattered from the spaces to the pattern sidewall. Finally, a Monte Carlo simulation showed that the distribution of the deposited energy on the pattern surface corresponds to the change of the pattern shape. Consequently, our study clarifies the importance of the effect of elastic shape change and the impact of the electrons scattered from the underlying layer to the sidewall on photoresist shrinkage. [ABSTRACT FROM AUTHOR]

The critical-dimension scanning electron microscope (CD-SEM) is an essential tool for semiconductor fabrication process control because of its high resolution and high precision. However, in ArF lithography, the CD of resist changes during CD-SEM measurement due to shrinkage caused by the electron beam irradiation. This shrinkage can be reduced by measurement parameters; however, there is a trade-off relationship between shrinkage and precision. Thus, measuring the CD of an ArF resist pattern precisely with small shrinkage is difficult. The authors propose an optimization method using the Taguchi method. Four measurement parameters were chosen as control factors for an L18 orthogonal array: probe current, acceleration voltage, horizontal length of field-of-view, and number of image acquisitions. As a result, high prediction accuracy was obtained that is smaller than 0.2 nm for shrinkage and 0.1 nm for precision. Moreover, an optimum measurement condition that achieves 0.28 nm shrinkage and 0.37 nm precision was also obtained. Thus, the proposed method was demonstrated as a promising method to optimize CD measurement parameters. [ABSTRACT FROM AUTHOR]

To establish a method of measuring interconnect line-edge roughness (LER), low-k line patterns were observed and electric field concentration was simulated on the basis of observation results. Wedge-shaped LERs were observed at the edges of low-k lines, and the bottom and the top widths of the average wedge feature were 60 and 7 nm (or smaller), respectively. Simulation showed that LER causes serious electric field concentration, which may cause the degradation of time-dependent dielectric breakdown (TDDB) lifetime at 100-nm-pitch Cu/low-k interconnects. The maximum electric field strength depends on the conventional LER metric 3Rq, but depends more strongly on the wedge angle, the curvature of the tip. That is, other metrics such as wedge angle can predict fatal electric field concentration caused by LER than the conventional metric 3Rq. [ABSTRACT FROM AUTHOR]

Colonic luminal aromatic amines have been historically considered to be derived from dietary source, especially fermented foods; however, recent studies indicate that the gut microbiota serves as an alternative source of these amines. Herein, we show that five prominent genera of Firmicutes (Blautia, Clostridium, Enterococcus, Ruminococcus , and Tyzzerella ) have the ability to abundantly produce aromatic amines through the action of aromatic amino acid decarboxylase (AADC). In vitro cultivation of human fecal samples revealed that a significant positive correlation between aadc copy number of Ruminococcus gnavus and phenylethylamine (PEA) production. Furthermore, using genetically engineered Enterococcus faecalis -colonized BALB/cCrSlc mouse model, we showed that the gut bacterial aadc stimulates the production of colonic serotonin, which is reportedly involved in osteoporosis and irritable bowel syndrome. Finally, we showed that human AADC inhibitors carbidopa and benserazide inhibit PEA production in En. faecalis .

A 1,4-addition strategy using an enone and a copper reagent was studied for the synthesis of (-)-piperitylmagnolol. A MOM-protected biphenol copper reagent was added to BF3·OEt2-activated 4-isopropylcyclohexenone, whereas 1,4-addition of protected monophenol reagents possessing an allyl group was found to be unsuccessful. The allyl group was later attached to the p-,p'-diiodo-biphenol ring by Pd-catalyzed coupling with allylborate. The aforementioned iodide was synthesized using a new method for ortho-selective deiodination of o-,p-diiodophenols.

The addition of MeLi to boron enolates produced by the 1,4-addition of Ar2Cu(CN)Li2 to BF3·OEt2-activated enones was followed by the reaction with ClP(O)(OEt)2 to afford the corresponding enol phosphates in moderate to good yields. The scope of this method was examined with sterically hindered or electronically biased enones and/or reagents. This activation of boron enolates was successfully applied to the synthesis of the methyl ether of Δ(9)-tetrahydrocannabinol.