Showing papers by "Toshitsugu Sakamoto published in 2006"

Effect of Ion Diffusion on Switching Voltage of Solid-Electrolyte Nanometer Switch

Abstract: A solid electrolyte switch turns on or off when a metallic bridge is formed or dissolved respectively in the solid electrolyte (here we use Cu2-αS). For logic applications, the switching voltage (<0.3 V) should be larger than the operating voltage of the logic circuit (about 1 V). We reveal that the switching voltage is mainly affected by Cu+ ionic transport in Cu2-αS and that a solid electrolyte with an ion diffusion coefficient smaller than that of Cu2-αS by several tens of orders of magnitude makes it possible to increase the switching voltage to 1 V.

Switching element, programmable logic integrated circuit and memory element

Abstract: A switching element with a switching voltage set higher than conventional, which includes an ion conduction layer including tantalum oxide, a first electrode provided in contact with the ion conduction layer, and a second electrode provided in contact with the ion conduction layer and capable of supplying the ion conduction layer with metal ions.

Switching Property of Atomic Switch Controlled by Solid Electrochemical Reaction

Abstract: We measured the switching time of an atomic switch that is operated by controlling the formation and annihilation of an atomic bridge in a nanogap between two electrodes using solid electrochemical reaction. The switching time becomes exponentially shorter with increasing the switching bias voltage. This exponential relation indicates that the switching time is determined by the solid electrochemical reaction, which is supported by theoretical estimation using a simple model. These results suggest the possibility that the atomic switch can be operated as fast as semiconductor devices currently used.

Solid-electrolyte nanometer switch

Abstract: We have developed a solid-electrolyte nonvolatile switch (here we refer as NanoBridge) with a low ON resistance and its small size. When we use a NanoBridge to switch elements in a programmable logic device, the chip size (or die cost) can be reduced and performance (speed and power consumption) can be enhanced. Developing this application required solving a couple of problems. First, the switching voltage of the NanoBridge (∼ 0.3 V) needed to be larger than the operating voltage of the logic circuit (> 1 V). Second, the programming current (> 1 mA) needed to be suppressed to avoid large power consumption. We demonstrate how the Nanobridge enhances the switching voltage and reduces the programming current.

Characteristics and Modeling of Sub-10-nm Planar Bulk CMOS Devices Fabricated by Lateral Source/Drain Junction Control

Abstract: Sub-10-nm planar bulk CMOS devices were demonstrated by a lateral source/drain (S/D) junction control, which consists of the notched gate electrode, shallow S/D extensions, and steep halo in a reverse-order S/D formation. Furthermore, the transport properties were also evaluated by using those sub-10-nm planar bulk MOSFETs. The direct-tunneling currents between the S/D regions, with not only the gate length but also the "drain-induced tunneling modulation (DITM)" effects, are clearly observed for the sub-10-nm CMOS devices at low temperature. Moreover, a quantum mechanical simulation reveals that the tunneling currents increase with the increase in the temperatures and gate voltages, resulting in a certain amount of contribution to the subthreshold current even at 300 K. Therefore, it is strongly required that the supply voltage should be reduced to suppress the DITM effects for the sub-10-nm CMOS devices even under the room-temperature operations

Nonvolatile solid-electrolyte switch embedded into Cu interconnect

Abstract: A solid-electrolyte switch (ldquoNanoBridgerdquo) has been successfully embedded into a 0.13-mum-node dual-damascene Cu interconnect using a highly reliable bilayer solid-electrolyte (TaSiO/Ta2O5) and a thin oxidation barrier, resulting in an excellent ON/OFF ratio (> 109) at a low ON resistance of 50Omega. The newly developed bilayer solid-electrolyte has improved the thermal stability during the BEOL process as well as improved electrical breakdown. The CMOS compatible NanoBridge is a promising switch to achieve high-performance and low-cost programmable LSIs.

Solid electrolyte switching element, and fabrication method of the solid electrolyte element, and integrated circuit

Abstract: The switching element of the present invention is of a configuration that includes: a first electrode ( 14 ) and a second electrode ( 15 ) provided separated by a prescribed distance; a solid electrolyte layer ( 16 ) provided in contact with the first electrode ( 14 ) and the second electrode ( 15 ); a third electrode ( 18 ) that can supply metal ions and that is provided in contact with the solid electrolyte layer ( 16 ); and a metal diffusion prevention film ( 17 ) that covers points of the surface of the solid electrolyte layer ( 16 ) that are not in contact with the first electrode ( 14 ), the second electrode ( 15 ) or the third electrode ( 18 ). This configuration prevents the adverse effect of metal ions upon other elements.

Solid electrolytic switching element, method for manufacturing such solid electrolytic switching element and integrated circuit

Abstract: A switching element is provided with a first electrode (14) and a second electrode (15) arranged at a prescribed interval; a solid electrolytic layer (16) brought into contact with the first electrode (14) and the second electrode (15); a third electrode (18) which is brought into contact with the solid electrolytic layer (16) and can supply a metal ion; and a metal diffusion preventing film (17) for covering a portion on the surface of the solid electrolytic layer (16) not covering any of the first electrode (14), the second electrode (15) and the third electrode (18). Thus, metal ion is prevented from affecting other elements.