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Solution culture experiments were conducted to investigate the effects of silicon (Si) on arsenate (As(V)) uptake by rice. The addition of Si to the pretreatment or uptake solution significantly decreased shoot and root As concentrations (P<0.001 and P<0.05). The presence of Si in the pretreatment or uptake solution also significantly decreased shoot P concentrations (P<0.001). The data demonstrated that both internal and external Si inhibited the uptake of As and P. Results of As uptake kinetics showed that the mechanism of the effect of Si on arsenate uptake is not caused by direct competition for active sites of transporters with As. The effect of Si on As uptake was not entirely mediated through the effect of Si on P uptake. Although the addition of Si to pretreatment solutions still significantly decreased shoot and root As concentrations, the extent of reduction became smaller when rice roots were coated with iron plaque.

In this paper, we study the effect of highly doped n^+/p^+ Si as the bottom electrode on unipolar RRAM with Ni-electrode/\HfOx structure. With heavily doped p^+-Si as the bottom electrode, RRAM devices illustrate the coexistence of the bipolar and the unipolar resistive switching. Meanwhile, by substituting heavily doped n^+-Si, the switching behavior changes to that of the self-rectifying unipolar device. The asymmetry and rectifying reproducible behavior in a n^+-\Si/HfOx/\Ni device resulted from the Schottky barrier of defect states in the \SiOx/\HfOx junction and n^+ Si substrate, but this behavior is not seen for the p^+-Si bottom electrode case. With rectifying characteristics and high forward current density observed in the \Ni/HfOx/\n^{+}\Si device, the sneak current path in the conventional crossbar architecture was significantly suppressed. We believe that the proposed structure is a promising candidate for future crossbar-type RRAM applications. [ABSTRACT FROM AUTHOR]

In this brief, high-\kappa HfZrO (via atomic layer deposition) fabricated by a novel multideposition multiroom-temperature annealing (MDMA) technique in ultraviolet-ozone (UVO) ambient is systematically investigated by both electrical and physical characterization and is integrated with a TiN metal gate in a gate-last process. Compared with the conventional rapid-thermal-annealed sample, it is found that the device annealed via MDMA in UVO demonstrates the following: 1) more than one order of leakage current reduction at 25 ^\circ\C and 125 ^\circ\C without an equivalent oxide thickness penalty; 2) less susceptibility to stress-induced degradation; and 3) improved time-dependent dielectric-breakdown lifetime. Grain boundary suppression and healing of oxygen vacancies are believed to be responsible for the improvement, as evidenced by scanning tunneling microscopy and X-ray photoelectron spectroscopy analysis. [ABSTRACT FROM AUTHOR]

Solution culture experiments were conducted to investigate the effects of silicon (Si) on arsenate (AsV) uptake by rice. The addition of Si to the pretreatment or uptake solution significantly decreased shoot and root As concentrations (P <0.001 and P <0.05). The presence of Si in the pretreatment or uptake solution also significantly decreased shoot P concentrations (P <0.001). The data demonstrated that both internal and external Si inhibited the uptake of As and P. Results of As uptake kinetics showed that the mechanism of the effect of Si on arsenate uptake is not caused by direct competition for active sites of transporters with As. The effect of Si on As uptake was not entirely mediated through the effect of Si on P uptake. Although the addition of Si to pretreatment solutions still significantly decreased shoot and root As concentrations, the extent of reduction became smaller when rice roots were coated with iron plaque. [Copyright &y& Elsevier]

In this letter, a bipolar resistive switching RAM based on \Ni/AlOy/\n^{+}\-\Si which exhibits high potential to realize transistor-free operation for cross-bar array is successfully demonstrated. The proposed device shows well-behaved bipolar memory performance with self-rectifying behavior in low-resistance state (> 700 at 0.2 V), a high on/off resistance ratio (> \10^3), a good retention characteristic (> \10^4\ \s at 100 ^\circ\C ), and a wide readout margin for cross-bar architecture (number of word line N > \2^5 for worst case condition). [ABSTRACT FROM AUTHOR]

In this letter, a resistive random access memory based on Ni electrode/ \HfOx dielectric/\n^+ Si substrate structure is demonstrated, which can be integrated with Si diode as selector for application in crossbar architecture. The unipolar device shows well-behaved memory performance, such as high on/off resistance ratio ( > \10^3), good retention characteristics ( > \10^5\ \s at \150\ ^\circ\C), satisfactory pulse switching endurance ( > \10^5\ \cycles), and a fast programming speed of about 50 ns. More importantly, it also exhibits almost 100% device yield on a 6-in wafer. [ABSTRACT FROM PUBLISHER]