This chapter elaborates on the general thought process behind Society 5.0 and lists the relevant nomenclature. As per the Japanese government literature, Society 5.0 should be one that, "through the high degree of merging between cyberspace and physical space, will be able to balance economic advancement with the resolution of social problems by providing goods and services that granularly address manifold latent needs regardless of locale, age, sex, or language." The vision

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A three-dimensional (3-D) vertical chain-cell-type phase-change memory (VCCPCM) for next-generation large-capacity storage was developed. The VCCPCM features formation of memory holes in multi-layered stacked gates by using a single mask and a memory array without a selection transistor. As a result of this configuration, the number of process steps for fabricating the VCCPCM is reduced. The excellent scalability of the VCCPCM's new phase-change material makes it possible to reduce the cell size beyond the scaling limit of flash memory. In addition, a poly-silicon selection diode makes it possible to reduce the cell factor to 4F 2 . Consequently, relative cost of the VCCPCM compared to 3-D flash memory is reduced to 0.2. IntroductionThe most important requirement for the storage-memory market is reduction of bit cost, and that requirement has been met by reducing the cell size of flash memory. However, high-voltage operation of flash memory makes it difficult to further reduce cell size. It has recently been reported that the bit-cost reduction can be continued by utilizing 3-D flash memory [1]. 3-D flash memory needs fewer process steps compared to simple stacking of flash memory, but reducing cell size is difficult for two reasons. Firstly, a 20-nm-thick ONO layer in the memory hole is needed and, secondly, a vertical poly-silicon selection MOS transistor needs a cell factor of 6F 2 [1]. In this work, a vertical chain-cell-type phase-change memory (VCCPCM), which can overcome these problems concerning 3-D flash in view of bit cost, is proposed. The key technologies of this VCCPCM are (1) a vertical chain cell for reducing the number of process steps, (2) a scalable new phase-change material for reducing cell size, and (3) a poly-Si XY-selection diode for reducing cell factor to 4F 2 . A poly-Si diode [2] and a lateral chain-cell-type PCM [3] were previously developed. Relative bit cost of both 3-D flash memory and VCCPCM is shown in Fig. 1. By virtue of technologies (1) to (3), the relative bit cost of the VCCPCM compared to 3-D flash memory is reduced to 0.2. Table 1 compares characteristics of 3-D flash memory and VCCPCM. In the present study, set, reset, and reading operations of the VCCPCM were confirmed. Moreover, off-current variation of the poly-Si diode was suppressed by short-time annealing.2. Device structure and operation method The structure of the VCCPCM is shown in Fig. 2. The poly-Si selection diode and VCCPCM are connected serially and positioned at the cross points between the bit and word lines. The structure and equivalent circuit of a VCCPCM are shown in Fig. 3. The gate oxide, channel poly-silicon, and the phase-change material are formed on the side of the holes in the stacked gates. Each memory cell consists of a poly-silicon transistor and a phase-change layer connected in parallel. The memory cells are connected serially in the vertical direction. In the set/reset operations, an off-voltage is applied to the gate at the selected cell, and a positive on-voltage is applied to the unselect...

We investigated the differences between two well-known optimization principles for understanding movement planning: the minimum variance (MV) model of Harris and Wolpert (1998) and the minimum torque change (MTC) model of Uno, Kawato, and Suzuki (1989). Both models accurately describe the properties of human reaching movements in ordinary situations (e.g., nearly straight paths and bell-shaped velocity profiles). However, we found that the two models can make very different predictions when external forces are applied or when the movement duration is increased. We considered a second-order linear system for the motor plant that has been used previously to simulate eye movements and single-joint arm movements and were able to derive analytical solutions based on the MV and MTC assumptions. With the linear plant, the MTC model predicts that the movement velocity profile should always be symmetrical, independent of the external forces and movement duration. In contrast, the MV model strongly depends on the movement duration and the system's degree of stability; the latter in turn depends on the total forces. The MV model thus predicts a skewed velocity profile under many circumstances. For example, it predicts that the peak location should be skewed toward the end of the movement when the movement duration is increased in the absence of any elastic force. It also predicts that with appropriate viscous and elastic forces applied to increase system stability, the velocity profile should be skewed toward the beginning of the movement. The velocity profiles predicted by the MV model can even show oscillations when the plant becomes highly oscillatory. Our analytical and simulation results suggest specific experiments for testing the validity of the two models.

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The superlattice film with the periodical thin film layers of Sb2Te3/GeTe used as a phase change memory was studied for deposition in the crystal phase. We successfully fabricated the superlattice structure with the sputtering temperature of 200 °C. Moreover, the pillar structure with the size of 70 nm was dry-etched using a HBr/Ar gas mixture.

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