BACKGROUND AND PURPOSE:Although neuroimaging plays an important role in the diagnosis of idiopathic normal pressure hydrocephalus, its predictive value for response to shunt surgery has not been established. The purpose of the current study was to identify neuroimaging markers that predict the shunt response of idiopathic normal pressure hydrocephalus.

Copper gallium sulfide with a chalcopyrite-type structure (CuGa 3 S 5 ) and a band gap of ca. 2.4 eV was prepared by a solid-state reaction. The as-prepared CuGa 3 S 5 exhibited photocatalytic hydrogen evolution activity in an aqueous solution containing Na 2 S and Na 2 SO 3 as sacrificial electron donors under visible-light irradiation (λ > 420 nm), even without a cocatalyst, such as platinum (Pt). The photocatalytic activity, however, was improved by the deposition of noble metal cocatalysts. Among the noble metals tested, rhodium (Rh) was found to be the most effective cocatalyst to improve the H 2 evolution activity, which was 2.5 times that achieved without a cocatalyst. Dispersion of base sulfides, including nickel sulfide (NiS) and iron sulfide (FeS), into the reactant solution containing CuGa 3 S 5 also increased the activity. The activity under optimized conditions (5.0 wt % NiS/CuGa 3 S 5 ) was 3 times that of a similarly optimized Rh/CuGa 3 S 5 . The results of electrochemical measurements and photocatalytic reactions suggested that NiS suspended in the reactant solution accepts electrons from the excited state of CuGa 3 S 5 to reduce H + into H 2 when NiS and CuGa 3 S 5 particles collide with each other in the reactant solution.

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Unified transient and frequency domain noise simulation of random telegraph noise and flicker noise is conducted using a multiphonon-assisted model that considers tunneling probabilities and energy transitions of discretized traps in the gate insulator of MOSFETs. The proposed model is able to concurrently represent the dynamic behavior of electron and hole trapping and detrapping via interactions with both the Si substrate and Poly-Si gate. The model is implemented in a 3-D device simulator to examine the effect of device structure and bias conditions. The conventional analytical model does not precisely estimate the noise powers in short-channel MOSFETs due to the nonuniform trapped charge effect. The high trap density near the shallow trap isolation edges is predicted quantitatively by comparing the measured data with the simulated data. In conclusion, we confirm the validity of the developed unified simulator and its usefulness for gaining insights into trap sites and noise reduction engineering.Index Terms-Device simulations, flicker noise, random telegraph noise (RTN), trap distribution.

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A new model of the roughness correlation function S(r) has been proposed in order to explain the different behavior of high field mobility limited by surface roughness scattering, µ SR , between electrons and holes in metal oxide semiconductor field effect transistors (MOSFETs) with oxynitrides. It has been shown, for the first time, that the change in electron and hole µ SR associated with NO oxynitridation can be reasonably well explained by the appropriate choice of the form of S(r).

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Intrinsic correlation between mobility reduction by remote Coulomb scattering (RCS) and threshold voltage shift (ΔV t ), both of which are induced by interface dipole modulation at high-k/SiO 2 interface, is investigated. Three types of dipole modulation are examined; Al addition, La addition, and changing quality of interfacial SiO 2 layer. Extrinsic scattering components due to increases of interface state and surface roughness are extracted and separated. It is found that RCS due to interface dipole modulation by Al addition increases with increasing ΔV t , while that by La addition is constant, independent of ΔV t . Inevitability of additional scattering for ΔV t is discussed based on two different models for dipole formation mechanisms. IntroductionAggressive MOSFET device scaling requires a metal gate (MG)/high-k insulator (HK) gate stack [1] . Achieving suitable threshold voltage (V t ) for CMOS is one of the biggest issues for introduction of MG/HK stack, especially in production by gate-first process. Recently, the presence of energy offset at the high-k/SiO 2 interface is evidenced [2][3][4] , which is attributed to interfacial dipole layer. V t control technique by modulation of the interface dipole with adding atoms has been developed for CMOS integration. La [2,[5][6][7][8] and Al [3,4,9] are widely known to be effective for lowering V t of nMOS and pMOS, respectively. V t shift (ΔV t ) of several hundred mV due to interface dipole modulation corresponds to formation of charges (negative and positive) of larger than 10 13 cm -2 at the high-k/interfacial layer (IL) interface, which may affect channel mobility (μ) by remote Coulomb scattering (RCS) mechanism [10] . From observation of strong correlation between μ reduction and ΔV t , Ota et.al. [11] proposed a model that interface dipole scattering governs μ of high-k MOSFET. According to this model, tradeoff relation between μ reduction and ΔV t is inevitable. However, there are several reports showing an unaffected μ for V t shifted device [7,8] . It is of great importance to clarify intrinsic correlation between μ reduction and ΔV t after correcting μ reduction by extrinsic effects depending on processes.In this paper, we systematically investigate quantitative correlation between μ reduction and ΔV t . Three types of V t shifts are examined; Al addition, La addition, and changing quality of IL. Extrinsic scattering components by increases of interface state and surface roughness are experimentally