High speed (1ns) and low voltage (1.5V) demonstration of 8Kb SOT-MRAM array

Abstract

We demonstrated an 8Kb SOT-MRAM array which achieves the highest field-free switching speed (1ns) never reported. The low transistor switching voltage (V <inf xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">SW</inf> ) 1.5V at switching current density (J <inf xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">SW</inf> ) 68MA/cm <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sup> is attributed to the unique tungsten-based cSOT channel material (SCM) which provides high spin-Hall angle (~0.6) and low resistivity (160μΩ-cm) with 400℃ thermal budget. The 8Kb SOT-MRAM array also showed good read window and array yield thanks to the promising MTJ etching process. Excellent performances such as high retention ( >>10 years at RT) and high endurance 7e12 cycles are demonstrated as well.