Endurance Enhancement by Soft Forming Algorithm on AlOx/WOy Resistive Switching Memory Array

A new soft forming algorithm, proposed in this letter, is demonstrated to improve endurance of an AlO_x/WO_y bilayer resistive random access memory array by two orders of magnitude. Relative to the conventional strong forming algorithm, soft forming creates a thinner conductive filament (CF) by applying voltage pulses that have narrower widths and lower amplitude. The mechanism can be explained by a CF model. soft forming algorithm is beneficial to form a thinner CF, which contains more movable oxygen vacancies (Vo) than that is formed by strong forming method. The rupture of thinner CF requires less movable oxygen ions (O^2-). Consequently, exhaustion of movable Vo/O^2- slows down and the number of set/reset cycles is increased, which improves endurance of the array.