Figure 2.

Manipulation of TA-states of PC materials by utilizing electrical-excitation pulses for PCM applications. a) LO-HI pulse excitations for fast and power-efficient SET operations. The inset shows a typical waveform of stimulus and ACT pulses. b) Variation of the minimum current required for full crystallization of cells with different sizes. By applying an electrical pulse (50 ns) with varying voltages, the minimum current required for full crystallization was measured for as-quenched cells without being stimulated and for cells exposed to the stimulus pulse (0.3 V/1 μs) prior to the measurement. c) Parallel-writing scheme in PCM devices. To write a cell, the input i is applied to activate all the cells in the row via the WL, while S₀ or S₁ is applied to switch one of the cells in the row from the amorphous to the crystalline state via the BL. S₀ and S₁ are comprised of a stimulus pulse and an ACT pulse.