Bidirectional Two-Terminal Switching Device for Non-Volatile Random Access Memory

A two-terminal N + /P/N + Si junction device that can replace the conventional selective transistor was studied as a bilateral switching device for spin transfer torque magnetic random access memory (STT-MRAM), by three-dimensional device simulation. An N + /P/N + junction structure with $30\times 30$ nm 2 area provides sufficient bidirectional current flow to write data by a drain-induced barrier lowering (DIBL) under a reverse bias at the N + /P (or P/N + ) junction, and high current on/off ratio of $10^{6}$, which is acceptable for STT-MRAM. In this work, critical parameters such as P-length, P doping, and N + doping are investigated to elucidate the optimal parameter condition in view of write current and current on/off ratio.