Reliability Analysis and Comparison of Implication and Reprogrammable Logic Gates in Magnetic Tunnel Junction Logic Circuits

Non-volatile logic is a promising solution to overcome the leakage power issue which has become an important obstacle to scaling of CMOS technology. Magnetic tunnel junction (MTJ)-based logic has a great potential, because of the non-volatility, unlimited endurance, CMOS compatibility, and fast switching speed of the MTJ devices. Recently, by direct communication between spin-transfer-torque-operated MTJs, several realizations of intrinsic logic-in-memory circuits have been demonstrated for which the MTJ devices are used simultaneously as memory and computing elements. Here, we present a reliability analysis of the MTJ-based logic operations and show that the reliability is an essential prerequisite of these MTJ-based logic circuits. It is demonstrated that for given MTJ device characteristics, the implication logic architecture, a new kind of logic based on material implication, significantly improves the reliability of the MTJ-based logic as compared to the reprogrammable logic architecture which is based on the conventional Boolean logic operations AND, OR, etc. Implementing the implication gates in spin-transfer torque magnetic random access memory arrays provides pure electrical read/write and logic operations and also allows fan-out to multiple outputs.