Fully Planar Impact Ionization (I2)-RAM Cell With High-Performance and Nondestructive Readout

This work presents a fully planar, nondestructive readout, and high-performance impact ionization random access memory (I
²
-RAM) cell having static random access memory (SRAM) characteristics. The proposed memory cell consists of a bipolar I
²
MOSFET (BIMOS) whose source region is shared with the drain region of a control gate (CG)-nMOS. The proposed I
²
-RAM offers excellent static characteristics, including write “1” (W1) time of ~0.5 ns, superior nondestructive readout time of ~0.4 ns, and sense margin (SM) of ~242 μA/μm at room temperature (300 K). The proposed I
²
-RAM cell also shows a static retention time (RT) >3600 s at a lower supply voltage of V
_DS
= 1.1 V for 300 K and 358 K temperatures. It additionally has a high read current ratio of ~ 2×10
⁹
and ~ 4×10
⁷
at temperatures 300 and 358 K, respectively. The proposed I
²
-RAM cell is promising candidate for embedded-RAM and high-performance applications.