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The superconducting properties of Nb3Sn strands are very sensitive to strain. Measuring internal strain of Nb3Sn in Cable-In-Conduit Conductors (CICC) is important for evaluating the superconducting performance of CICC. Internal strain can be determined by neutron diffraction measurement using Takumi of J-PARC. Neutron diffraction measurement becomes a strong tool for evaluating directly the internal strain of Nb3Sn in CICC.

A simplified method of effective work function (Phieff) control to near the Si conduction band edge (Ec) was demonstrated in the Ni fully silicided (Ni-FUSI) gate/HfSiON system. The Phieff of NiSi (4.51 eV) decreased and saturated at 4.27 eV, owing to the use of an Al postdoping process, in which the implantation of Al ions into the upper part of the Ni silicide gate electrodes was followed by low-temperature drive-in annealing ( les 500degC) . There is no degradation of the gate leakage characteristics at the Ni-FUSI/HfSiON interface. The metallic state of piled-up Al just at the Ni-FUSI/HfSiON interface seems to be responsible for the Phieff near the vacuum work function of Al. The Al postdoping process simplifies a dual metal gate process, owing to single-step Al implantation for nMOS devices without complicated metal etching process for pMOS region. The physical mechanism of bidirectional Phieff modulation of Al pileup was also investigated. It was revealed that the opposite Phieff modulation, which is the increase in Phieff, occurs, owing to the formation of interfacial Al2O3 layer at the Ni-FUSI/SiO2 interface. Although the Al2O3 state also formed, it has little influence on the Phieff value at the Ni-FUSI/HfSiON interface.

Fully Ni-germanosilicided [Ni(SiGe)] gate electrode was systematically investigated by means of both structural analyses and electrical measurements. The authors fabricated Ni(SiGe)-gated MOS capacitors with various Ge fractions through the solid-phase reaction at Ni/polycrystalline SiGe (poly-SiGe) interface. It was found that Ge atoms can only be dissolved in NiSi phase, and then Ni(SiGe) phase is formed. In addition, even in the case that the thickness ratio of Ni to Si is equivalent to that required to form Ni2Si, Ge atoms induce phase change from Ni2Si to Ni(SiGe) near SiO2 interface. This phenomenon promotes condensation of Ge atoms in Ni(SiGe). The values of effective work function (Phieff) are independent of the Ge fraction in the low Ge fraction (Ge < 60%) Ni(SiGe) gate. On the contrary, the Phieff values begin to change to values larger than that of NiSi in the case of a Ge fraction higher than 60%. In addition, the Ge incorporation modulates the Phi eff shift effect of piled-up B atoms to the opposite direction compared to the NiSi cases reported previously. As a result, the controllable Phieff range for piled-up B atoms can be expanded to 0.47 eV near the Si midgap

The elastic properties of REBCO tape (i.e., REBa2Cu3 O7-d, RE = Y, Sm and Gd) have been investigated by means of diffraction techniques using synchrotron radiation. Total local strain Ahkll, which consists of thermal strain AhklT and lattice strain Ahkl, was analyzed using a microscopic structure model, with two types of microtwin configuration along the tensile axis, i.e., with the [100] or [110] crystal axis oriented parallel to the longitudinal direction of the tape. Experimental results were: (a) slope dAh00l/dA is larger than dA0k0l/dA (where A is the external tensile strain), which is attributed to the elastic modulus Ea along the a-axis being smaller than Eb along the b-axis; (b) both dAh00l/dA and dA0k0l/dA are smaller than unity, but dA110l/dA is almost unity depending on the configuration of microtwin; (c) the thermal strain for different planes is different as Ah00T ≠ A0k0T due to the elastic behavior of the superconducting layer being modified because it is constrained by the substrate and the outer metallic layer; and (d) a large Poisson ratio is attributed to this constraint state. It is suggested that the microtwin structure is critical to understand and model this unusual stress/strain behavior.