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Program characteristics of FinFET split-gate metal oxide nitride oxide silicon (SG-MONOS) is analyzed using TCAD simulation. Source-side injection (SSI) program is found to be insensitive to the field enhancement at Fin corners in contrast to FN program, which shows the robustness of SSI program of FinFET SG-MONOS to Fin shape variation in the fabrication process. The simulation also indicates that incremental step pulse programming (ISPP) combined with SSI program reduces the field enhancement and improves oxide reliability.

The effect of field enhancement at Fin corners on program characteristics of FinFET Split-gate metal oxide nitride oxide silicon (SG-MONOS) is analyzed. The program characteristics using source-side injection (SSI) are found to be insensitive to the variation of the curvature radius at Fin corners, which shows the robustness of FinFET SG-MONOS to Fin shape variation inthe fabrication process.

In this paper, we propose a new analytical electron mobility model in strained Si inversion layers suitable for implementation in a drift-diffusion simulator. Using our new model, a numerical study in conjunction with comprehensive bending experiments has demonstrated that (100)-Si has the optimum channel direction along in terms of the device performance of strained 65-nm-node nMOSFETs with contact etch stop layer and that both the shear-strain component and the quantum confinement effect are key factors in contributing to this superiority.

The effect of hydrogen incorporation into nitrogen vacancies in silicon nitride on electron trap is analyzed using density functional theory method. A hydrogen atom is attached to a dangling bond which is well separated from other dangling bonds, whereas it is not attached to ones which strongly interact because of lattice distortion. An electron trap level caused by nitrogen vacancy becomes shallow by hydrogen incorporation. An electron is trapped in a deep level created by a silicon dangling bond before hydrogen incorporation, whereas it is trapped in a shallow level created by an anti-bonding state of a siliconsilicon bond after hydrogen incorporation. The simulation results qualitatively explain the experiment in which reduced hydrogen content in silicon nitride shows superior retention characteristics of the programmed state.

Hybrid peptides were constructed from endothelin B receptor (ET(B)) selective antagonist RES-701-1 (1) and endothelin (ET-1). They have N-terminal 10 amino acids derived from 1 and C-terminal 10 amino acids derived from ET-1. RES-701-1(1-10)-[Ala15]ET-1(12-21) and its analogues substituted or truncated at the residues derived from RES-701-1 had proved to possess high receptor binding activity selective for ETB as well as 1. Substitutions at the residues derived from ET-1 had produced some analogues that possessed high affinity not only for ETB but for ETA. Although all analogues had antagonistic effects on ETA, some analogues had proved to function as agonist on ETB confirmed by the changes in intracellular calcium concentrations of ET receptor-transfected COS-7 cells. We have found four types of ET receptor-binding peptides: (1) ETB-selective agonist with weak ETA antagonism (3, KT7421); (2) ETB-selective antagonist with weak ETA antagonism (29, KT7539); (3) ETB agonist with potent ETA antagonism (27, KT7538); and (4) non-selective ETA/ETB antagonist (26, KT7540).

EI-1511-3, -5 and EI-1625-2, novel interleukin-1 beta converting enzyme (ICE) inhibitors, were isolated from the culture broths of Streptomyces sp. E-1511 and E-1625. EI-1511-3, -5 and EI-1625-2 selectively inhibited the recombinant human ICE activity with IC50 values of 0.09, 0.38 and 0.2 microM, respectively. Taxonomy, fermentation of the producing strain and isolation of EI-1511-3, -5 and EI-1625-2 are described.

EI-1507-1 and -2, novel interleukin-1 beta converting enzyme (ICE) inhibitors, were isolated from the culture broths of Streptomyces sp. E-1507. EI-1507-1 and EI-1507-2 selectively inhibited the recombinant human ICE activity with IC50 values of 0.23 and 0.42 microM, respectively. EI-1507-1 and EI-1507-2 also inhibited mature interleukin-1 beta secretion from THP-1 cells with IC50 values of 1.1 and 1.4 microM, respectively.

The effects of a novel N- methyl- d -aspartate (NMDA) receptor antagonists, ES-242-1 3,3′-dimethyl-3,4,3′,4′-tetrahydro-6,8,6′8′-tetramethoxy-[10,10′-bi-2-oxanthracene]-4,9,9′(1 H ,1′ H )-triol 4-acetate, on NMDA-induced increases of intracellular Ca 2+ concentration in cultured hippocampal neurons were examined.ES-242-1 selectively blocked the NMDA-induced increase in intracellular free Ca 2+ concentration ([Ca 2+ ] i ), but not the [Ca 2+ ] i increase stimulated by quisqualate or kainate. The effect of ES-242-1 appeared in the slow development of a blockade of [Ca 2+ ] i (half blocking time: 90sec) when 100 μM NMDA was applied with 10 μM ES-242-1, whereas the initial [Ca 2+ ] i rise was attenuated by 10 μM ES-242-1 when the latter was applied with a lower concentration of NMDA (10 μM). This is consistent with a previous observation that ES-242-1 binds to both the transmitter recognition site and the channel domain. The blockade by ES-242-1 was reversed by washing. In constrast, the blockade by MK-801 was not relieved easily by washing. These results suggest that ES-242-1 blocks the NMDA-induced [Ca 2+ ] i increase due to a combination of two well-recognized mechanisms, which are different from that of MK-801, at the NMDA receptor.

RES-701-1, a novel cyclic peptide endothelin antagonist, was isolated from the culture broth of Streptomyces sp. RE-701. RES-701-1 selectively inhibited the ET-1 binding to type B endothelin receptor (ETB receptor) with an IC50 of 10 nM expressed in CHO cells and blocked the ET-1-induced elevation of intracellular free Ca2+ concentration in ETB receptor-expressing COS-7 cells. Characterization of producing strain, fermentation, isolation, structure, physico-chemical and biological properties of RES-701-1 are described.

RES-1214-1 and -2, novel and non-peptidic endothelin antagonists, were isolated from the cultured broth of a fungus, Pestalotiopsis sp. RE-1214. RES-1214-1 and -2 selectivity inhibited the ET-1 binding to endothelin type A receptor (ETA receptor) with IC50 values of 1.5 microM and 10 microM, respectively. RES-1214-1 and -2 inhibited the increase in intracellular Ca2+ concentration elicited by 1 nM ET-1 in A10 cells. Taxonomy of producing strains, fermentation, isolation, structural determination, and biochemical properties of RES-1214-1 and-2 are described.

We have developed a system consisting of a full-3D process simulator for stress calculation and k · p band calculation that takes into account the subband structure. Our simulations are in good agreement with the experimental data of strained Si-pMOSFETs of 65nm technology devices. This system is a powerful tool to optimize device structures with all stress components.

Numerical study in conjunction with comprehensive bending experiments has demonstrated that (100)-Si has the optimum channel direction along in terms of the device performance of strained 65nm-node nMOSFETs with Contact Etch Stop Layer (CESL), and that both the shear strain component and the quantum confinement effect play an important role in this superiority.

Hydrogen incorporation into nitrogen vacancies in silicon nitride and its effects on electron trap level are analyzed using simulation based on density functional theory with temperature- and pressure-dependent hydrogen chemical potential. If the silicon dangling bonds around a nitrogen vacancy are well separated each other, hydrogen incorporation is energetically stable up to 900 °C, which is in agreement with the experimentally observed desorption temperature. On the other hand, if the dangling bonds strongly interact, the incorporation is energetically unfavorable even at room temperature because of steric hindrance. An electron trap level caused by a nitrogen vacancy becomes shallow by the hydrogen incorporation. An electron is trapped in a deep level created by a silicon dangling bond before hydrogen incorporation, whereas it is trapped in a shallow level created by an anti-bonding state of a silicon-silicon bond after hydrogen incorporation. The simulation results qualitatively explain the experiment, in which reduced hydrogen content in silicon nitride shows superior charge retention characteristics.

Dehydroaltenusin, cyclooctasulfur, atrovenetinone, and altenusin were isolated from the culture broths of Penicillium verruculosum IAM-13756, Streptomyces verticillus subsp. tskushiensis ATCC-21633, Penicillium sp. SPC-16375, and Penicillium sp. SPC-16524, respectively, as new myosin light chain kinase (MLCK) inhibitors. These compounds inhibited the calmodulin-dependent activity of MLCK with IC50 values of 0.69, 0.86, 3.7, and 350 microM, respectively. Among them, dehydroaltenusin was the best MLCK inhibitor in terms of potency and selectivity examined in the purified enzyme systems.

A new series of 4-[4-(N-substituted carbamoyl)-1-piperazinyl]-6,7-dimethoxyquinazoline derivatives were found to show potent and selective inhibition of platelet-dervied growth factor (PDGF) receptor phosphorylation. In this exploration of the structure-activity relationships (SARs) of the prototype inhibitor KN1022, the 4-nitrophenylurea moiety was probed. We found that 4-substitution on the phenyl ring was optimal and the introduction of more than two substituents on the phenyl ring decreased activities. Bulky substituents on the phenyl ring enhanced activities. Thiourea analogues were also prepared, and the SARs were found to be slightly different from those of the urea derivatives. Through this research, we obtained some potent KN1022 derivatives such as 4-(4-methylphenoxy)phenyl (36, IC(50) 0.02 micromol/L), 4-tert-butylphenyl (16, IC(50) 0.03 micromol/L), and 4-phenoxyphenyl (21, IC(50) 0.08 micromol/L) analogues, which had almost a 10-fold increase in activity against KN1022. These potent compounds retained their high selectivity against the PDGF receptor family similar to KN1022. We also observed that these compounds could inhibit the PDGF-BB-induced proliferation of porcine vascular smooth muscle cells without cell toxicity almost at the same IC(50) values observed for PDGF receptor phosphorylation. To evaluate the biological effects in vivo, we selected some analogues on the basis of the measurement of the plasma drug concentration after oral administration to rats. Oral administration of the 4-chlorophenyl (6), 4-bromophenyl (9), or 4-isopropoxyphenyl (20) analogue to Sprague-Dawley rats (30 mg/kg, twice daily) resulted in significant inhibition (24-38%) of neointima formation in the carotid artery of the balloon catheter deendothelialized vessel in the rats. Therefore, 4-[4-(N-substituted carbamoyl)-1-piperazinyl]-6,7-dimethoxyquinazoline derivatives, which are potent inhibitors of PDGFR phosphorylation, may be expected to represent a new therapeutic approach for the treatment of various aspects of atherosclerosis and other cellular proliferative disorders.

We examined the effect of benidipine, a 1,4-dihydropyridine calcium channel blocker, on depolarizing stimulation-induced increases of intracellular calcium concentration ([Ca2+]i) in cultured mouse hippocampal neurons in comparison with those of nicardipine and nilvadipine. Benidipine (0.1-10 microM) inhibited the [Ca2+]i increase compared with the no drug control response. This effect was stronger than those of nicardipine and nilvadipine. The inhibitory effect of benidipine lasted even after washing out the drug for 125 min, while those of nicardipine and nilvadipine disappeared more rapidly. This is the first report that demonstrates that benidipine inhibits the [Ca2+]i increase in the neuron itself.

RES-1149-1 and -2, produced by Aspergillus sp. RE-1149, were found to be non-peptidic antagonists for endothelin type B receptor (ET(B) receptor). RES-1149-1 and -2 selectively inhibited the endothelin-1 (ET-1) binding to ET(B) receptor in a competitive manner with IC50 values of 1.5 microM and 20 microM, respectively. RES-1149-1 inhibited the increase in intracellular Ca2+ concentration elicited by 1 nM ET-1 in COS-7 cells expressing human ET(B) receptor, but not in the case of cells expressing ET(A) receptor. In addition, some structure-activity relationships are described.

RES-1214-1 and -2, novel and non-peptidic endothelin antagonists, were isolated from the cultured broth of a fungus, Pestalotiopsis sp. RE-1214. RES-1214-1 and -2 selectivity inhibited the ET-1 binding to endothelin type A receptor (ETA receptor) with IC50 values of 1.5 microM and 10 microM, respectively. RES-1214-1 and -2 inhibited the increase in intracellular Ca2+ concentration elicited by 1 nM ET-1 in A10 cells. Taxonomy of producing strains, fermentation, isolation, structural determination, and biochemical properties of RES-1214-1 and-2 are described.

RES-701-2, -3 and -4, novel cyclic peptide endothelin antagonists, were isolated from the culture broths of Streptomyces sp. RE-701 and RE-896, RES-701s selectively inhibited the ET-1 binding to endothelin type B receptor (ETB receptor) with IC50 values ranging from 5 to 20 nM. Taxonomy of the producing strains, fermentation, isolation and biochemical properties of RES-701s are described.

Dopant redistribution during gate oxidation in metal-oxide-semiconductor (MOS) fabrication processes has been studied by secondary-ion mass spectrometry (SIMS). In the first set of experiments, dopant profiles after gate oxidation are measured and compared to those after N2 annealing. From the measured profiles, the contribution of oxidation-enhanced diffusion (OED) to the entire dopant redistribution is determined and an OED model parameter is calibrated. In the second set of experiments, samples which are subjected only to wafer loading and unloading steps are prepared and dopant profiles are measured. From the measured profiles, the magnitude of transient-enhanced diffusion (TED) which occurs during the wafer loading step is estimated and an interstitial-clustering parameter is calibrated. The parameters calibrated in this study are combined with the point-defect parameters taken from the literature, and dopant redistribution during the entire gate oxidation cycle is simulated. Calculated dopant profiles agree well with the measured SIMS profiles and show correct time dependence of TED and OED, as observed in the present experiments. In the simulations, interstitial concentration at the oxidizing Si/SiO2 interface is found to be 40 times the equilibrium concentration. The supersaturation caused by surface oxidation is small and the contribution of OED is negligible under typical gate oxidation conditions where oxide thickness is less than 100 Å. Dopant profiles after gate oxidation are mainly dominated by TED. However, as oxidation proceeds, the contribution of OED increases because it continues while TED almost ends in the wafer loading step of gate oxidation. Segregation of boron in the channel region is also studied. It is found that a greater amount of boron is lost in oxidation than in N2 annealing. The effect of segregation on device characteristics is not negligible for buried-channel PMOS devices, because the threshold voltage of the devices is sensitive to the change in the amount of boron.