Memory Operation of Z²-FET Without Selector at High Temperature

Abstract

The electrical performance of Z 2 -FET and memory operations of matrix are demonstrated at high temperatures up to 125 °C. The sharp subthreshold slope is maintained and the reliable operation is ensured within the memory window of 229 mV even though the turn on voltage of '0'-and '1'-states are shifted to lower voltage. The '0'-state current remains low while the '1'-state current gradually increases as the temperature increases leading to higher current margin. At the elevated temperature, the potential barriers are slightly reduced but does not collapse, which leads to the successful memory operation. However, increasing the temperature over 125 °C, the potential barrier at the '0'-state is significantly reduced and causes the failure of memory operation with high '0'-state current. The matrix demonstrates reliable memory operations without using selector circuits even at 125 °C.

A Review of Sharp-Switching Band-Modulation Devices

“…Matrix operation: The operation of the Z 2 -FET cell in an array configuration was first studied through simulations [49] and later characterized experimentally in a two-by-two cell matrix, with and without, a pass selector transistor [50]. Single-cell and word-length operations were successfully demonstrated at low [51] and high temperature [52], with promising immunity to bitline or wordline disturbances and an easy-to-scale design. A prototype 1 Mbit memory chip, fabricated with FD-SOI technology, proved fully functional, with reliable performance.…”

Understanding of carriers’ kinetic energy in steep-slope P+N+P+N+ feedback field effect transistor

“…Especially, the device using a positive feedback mechanism, e.g. FBFET, Z 2 -FET, and Z 3 -FET [12][13][14][15], exhibits attractive properties such as a low subthreshold swing (i.e. ∼0 mV/decade at 300 K), improved on-state drive current at a higher temperature [16,17], superior degree of saturation of output current [18], a low leakage current (∼10 12 A µm −1 or below) at a lower threshold voltage (<0.3 V), and reasonable switching speed (not like NEM relay) [19].…”