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The capability of Z2-FET (Zero Impact Ionization and Zero Subthreshold Slope FET) to operate as a sharp logic switch is demonstrated in advanced FD-SOI (Fully Depleted SOI) technology. The operation mechanism is band-modulation which enables remarkable DC performance in terms of ON/OFF current ratio and sharp switch (~1 mV/decade). Z2-FETs have successfully been used for ESD protection and capacitorless DRAM memory, but the presence of an inherent hysteresis has handicapped so far logic applications. However, this letter shows that fast pulses on the gate result in hysteresis-free switching: the device turns ON and OFF at same gate bias. The sharpness of the switch depends on device parameters, bias and speed of operation. Systematic experiments compare the performance of Z2-FETs with dual or single ground-planes. [ABSTRACT FROM AUTHOR]

The Z2-FET operation as capacitorless DRAM is analyzed using advanced 2-D TCAD simulations for IoT applications. The simulated architecture is built based on actual 28-nm fully depleted silicon-on-insulator devices. It is found that the triggering mechanism is dominated by the front-gate bias and the carrier's diffusion length. As in other FB-DRAMs, the memory window is defined by the ON voltage shift with the stored body charge. However, the Z2-FET's memory state is not exclusively defined by the inner charge but also by the reading conditions. [ABSTRACT FROM AUTHOR]