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The chemical reaction of residues formed on a quartz surface in an electron cyclotron resonance plasma during the etching of Al and resist film by Cl2 and BCl3 plasma was characterized in situ by infrared reflection absorption (IRA) spectroscopy and quadrupole mass spectrometry (QMS). The plasma was generated in a chamber with a structure similar to a conventional production machine. Incident ions and molecules impacting onto a quartz surface at the chamber wall were analyzed by QMS. Then the residue formed on a quartz film on a sample mounted on the chamber wall was analyzed by IRA spectroscopy. The residue was identified as B2O3 which is formed by incident boron chloride ions that diffuse down through the B2O3 residue to the quartz surface and, there, thermally react with OH in the quartz. The residue film produced on the quartz surface could be identified by etching a 1-μm-thick Al film ten times at the etching rate of 12 nm/s. This combination of IRA and QMS is a promising technique for refining on-li...

The outgassing characteristics of Invar samples oxidized in atmosphere at 600°C was measured by thermal desorption spectroscopy (TDS). The Outgassing rate of the oxidized Invar samples was three times larger than that of as-received Invar samples. After outgassing by heating in vacuum, no significant difference was found in the adsorption rates in atmosphere between the oxidized and as-received Invar samples. Once the samples were heated in vacuum, the length of exposure in atmosphere had little influence on the adsorption rates.

We have improved both the spatial resolution and precision of three-dimensional (3D) electron microscopy, which is based on conventional scanning transmission electron microscopy (STEM), by using a micro-pillar specimen together with a 3D analysis holder, and by introducing marker-assisted image alignment prior to 3D reconstruction. Our 3D STEM measurement of aggressively scaled metal-oxide-semiconductor (MOS) gate structures not only successfully showed the z-axis positional dependence of gate-edge profiles and edge-roughness profiles such as line edge roughness (LER) and line width roughness (LWR), but also revealed uniformity of each layer of which the gate structure was composed. Such observations are very important in controlling future device characteristics, but are difficult to obtain using other measurement techniques.

Extended abstract of a paper presented at Microscopy and Microanalysis 2009 in Richmond, Virginia, USA, July 26 – July 30, 2009

このたび我々は, 民生用VTRに搭載することを目的とした, 低コストで多機能なNTSC/PAL双方向方式変換用LSIシステムを開発した.本システムではフィールド間ライン内挿を採用することにより画質劣化を抑え, またLSI設計にマイクロプログラムを採用している.

To clarify the origin of on-state drain current (ION) variability in metal–oxide–semiconductor field-effect transistors (MOSFETs), we applied three-dimensional scanning transmission electron microscopy (3D STEM) observation to two transistors that had different ION values but the same threshold voltage (VT). The results clearly showed a difference in the distance between the gate and source/drain silicide, suggesting that the ION difference between two transistors can be explained by the difference in the source/drain extension resistance. We showed that it is possible to discuss the 3D device structures in relation to their electrical characteristics.

患者は75才,男性.再生不良性貧血および胃癌の治療経過中,発熱,意識障害,高度の血管内溶血をきたし,発熱後約18時間で死亡した.剖検所見では広範な皮下気腫に加え,心,肝,腎,脾等の臓器に気泡形成と無数の桿菌の増殖を認め,心室からの血液培養によってAeromonas hydrophilaが同定された.本症例はAeromonas hydrophila敗血症としてはきわめてまれな病像を呈したと考えられ,文献的考察を加えて報告した.

We have isolated cDNA clones of the mRNA for cytochrome P-450 that catalyzes the steroid C-21 hydroxylation (P-450(C21)), which specifically catalyzes 21-hydroxylation of steroids in the microsomes of bovine adrenal cortex by using synthetic oligonucleotides as probes. Sequence determination of the cloned cDNA showed that it contains 2157 nucleotides and a poly(A) chain and that a single open reading frame of 1488 nucleotides codes for a polypeptide of 496 amino acids with a molecular weight of 56,113. The deduced amino acid composition is in agreement with that determined by direct amino acid analysis of purified P-450(C21) and the predicted primary structure contained amino acid sequences of N-terminal region and two internal tryptic fragments of the protein so far analyzed. Comparing the amino acid sequence with those of other forms of P-450 reveals that a conserved amino acid sequence containing a putative heme-binding cysteine is present in the equivalent position, proximate to the COOH terminus of the molecules and that P-450(C21) is phylogenically situated in an intermediate position between steroidogenic mitochondrial cytochrome P-450 which catalyzes the side-chain cleavage of cholesterol (P-450(SCC)) and drug-metabolizing microsomal P-450s. However, the amino acid sequence of P-450(C21) is much closer to that of drug-metabolizing P-450s than to that of P-450(SCC).

Two 21-hydroxylase [P-450(C21)] genes have been isolated from a human genomic library using a bovine P-450(C21) cDNA. The insert DNAs containing the P-450(C21) genes were also hybridized with the sequences of the 5' or 3' end regions of human C4 cDNA, indicating a close linkage of the P-450(C21) gene to the C4 gene. Sequence analysis has revealed that the two P-450(C21) genes are both approximately equal to 3.4 kilobases long and split into 10 exons. Comparing the two sequences, we found that the two genes are highly homologous including their introns and flanking sequences, but that three mutations render one of the two P-450(C21) genes nonfunctional--1 base insertion, an 8-base deletion, and a transition mutation--all of which may cause premature termination of the translation. Tandem arrangement of the highly homologous pseudo- and genuine genes in close proximity could account for the high incidence of P-450(C21) gene deficiency by homologous gene recombination.

Gene expression of rat cytochrome P-450c (P-450c) depends upon inducible enhancers scattered in the 5′-upstream region of the gene. We show that expression of the P-450c gene is repressed by contransfection with adenovirus E1a DNA, regardless of the presence or absence of inducers, in a transient expression system of HeLa cells. Since cotransfection of either 13S or 12S E1a cDNA was effective in the repression, the region necessary for repression could be separated from that of transactivation of other adenovirus early genes. Moreover, we investigated the regions responsible for the inhibitory activity using in-frame deletion mutants lacking internal or external portions of the E1a proteins. The sequence responsible for the repression was located in the aminoterminal half of the E1a proteins. The inducible expression of the chimeric plasmid containing a 24-base-pair enhancer sequence of the P-450c gene placed in a heterologous promoter of SV40 was repressed by contransfection with E1a DNA, suggesting strongly that the inhibitory effect of the E1a proteins upon P-450c gene expression was caused by blocking the enhancer activity.

Transcription of the drug-metabolizing cytochrome P-450c gene is induced by 3-methylcholanthrene or 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD). Previously, we defined two xenobiotic responsive elements (XREs) of approximately equal to 15 base pairs, both of which activate transcription in cis in response to these xenobiotics. Using a gel mobility shift assay, we have identified a factor that specifically binds to the XREs. This factor appears in nuclei of mouse hepatoma cell line Hepa-1 only when the cells are treated with the xenobiotics, while the factor is undetectable in the nuclei of a 3-methylcholanthrene-treated mutant of Hepa-1 with defective function of a xenobiotic receptor. In addition, the nuclear factor bound to the XRE in the gel was found to be associated with [3H]TCDD when the cells were treated with it, suggesting that the xenobiotic receptor is at least a component of the DNA-binding factor. The cytoplasmic fraction from nontreated Hepa-1 cells also contains the factor as a cryptic form and prominently reveals its DNA-binding activity by incubation with 3-methylcholanthrene in vitro. These results not only suggest the involvement of the XRE-binding factor in transcriptional activation via XREs but also provide evidence that the binding of ligands to the preexisting factor in a cryptic form induces its XRE-binding activity, which is probably followed by its translocation from cytoplasm to nucleus.

The synthesis of cytochrome P-450c is induced remarkably in cultured cells as well as animal tissues in response to added chemicals such as 3-methylcholanthrene and 2,3,7,8-tetrachlorodibenzodioxin. To study this mechanism, we joined the sequence of 5'-flanking and upstream regions of the P-450c gene to the structural gene for chloramphenicol acetyltransferase. The fusion gene was introduced into Hepa-1 cells for the assay of the expressed acetyltransferase activity. At least three cis-acting regulatory regions that are responsible for the inductive expression were determined in the sequences from nucleotide -3674 to -3067, from -1682 to -1429, and from -1139 to -1029, relative to the transcription start site, by external deletion analysis. Further detailed analysis of the region (nucleotides -1139 to -1029) most influential on the inducibility revealed that a regulatory element consisting of 10 base pairs termed a drug regulatory element (DRE) and its homologues were tandemly arranged in this region. The consensus sequence deduced from DREs is 5'-GCNTGAGGCTGGG-3'. The regulatory sequence from nucleotide -1140 to -844 is capable of conferring inducibility on a heterologous promoter in a manner independent of its orientation and distance from the subordinate promoter.