Engineering of Hf1−xAlxOy amorphous dielectrics for high-performance RRAM applications

We propose for the first time a systematic evaluation of the performance and underlying trade-off of the use of ternary Hf_1-xAl_xO_y oxides for RRAM application. We show that intermixing HfO₂ and Al₂O₃ deposition cycles in a standard ALD process not only prevents crystallization of active layer but also significantly improve intrinsic retention and disturb-immunity properties at the expense of a small increase of programming voltage. We attribute this beneficial effect to the reduced V_o diffusivity caused by stronger Al-O bonds as suggested by ab-initio simulations.