In this letter, we explore the influence of the CuxTe1-x layer composition (0.2 < x < 0.8) on the resistive switching of CuxTe1-x/Al2O3/Si cells. While x > 0.7 leads to large reset power, similar to pure-Cu electrodes, x < 0.3 results in volatile forming properties. The intermediate range 0.5< x < 0.7 shows optimum memory properties, featuring improved control of filament programming using <5 mu A as well as state stability at 85 degrees C. The composition-dependent programming control and filament stability are closely associated with the phases in the CuxTe1-x layer and are explained as related to the chemical affinity between Cu and Te. (C) 2011 American Institute of Physics. [doi: 10.1063/1.3621835]