Abstract: A technique capable of improving speed of a set operation, which controls writing rate in a semiconductor device including a memory cell using a phase-change material. The technique uses means for setting a set-pulse voltage to be applied to the phase-change material to have two steps: the first-step voltage sets a temperature of the phase-change memory to a temperature at which the fastest nucleation is obtained; and the second pulse sets the temperature to a temperature at which the fastest crystal growth is obtained, thereby obtaining solid-phase growth of the phase-change material without melting. Moreover, the technique uses means for controlling the two-step voltage applied to the phase-change memory by a two-step voltage applied to a word line capable of reducing the drain current variation.

Abstract: Program voltages of a non-volatile memory device are controlled variably according to a program/erase operation count. The non-volatile memory device includes a program voltage supply unit for applying a program voltage to a memory cell, a program/erase count storage unit for storing a total program/erase operation count of the non-volatile memory device, a program start voltage storage unit for storing levels of program start voltages to be differently supplied according to the program/erase operation count, and a program voltage controller for controlling the program start voltage according to the program/erase operation count.

Abstract: A multibit electro-mechanical memory device and a method of manufacturing the same include a substrate, a bit line on the substrate; a lower word line and a trap site isolated from the bit line, a pad electrode isolated from a sidewall of the trap site and the lower word line and connected to the bit line, a cantilever electrode suspended over a lower void in an upper part of the trap site, and connected to the pad electrode and curved by an electrical field induced by a charge applied to the lower word line, a contact part for concentrating a charge induced from the cantilever electrode thereon in response to the charge applied from the lower word line and the trap site, the contact part protruding from an end part of the cantilever electrode, and an upper word line formed with an upper void above the cantilever electrode.

Abstract: A memory device of SRAM type has a memory plan constituted by base memory cells organized in lines and in columns. Each cell of a column is connected between two bit lines which are precharged during a reading operation. Circuitry is provided for generating a precharge voltage of the bit lines which is less than a nominal supply voltage of the device.