Structural and Electronic properties of Copper Doped amorphous Alumina*

To understand the atomic properties of Conducting Bridge Random Access Memory(CBRAM) devices based on Alumina with Copper as one of the active electrodes, we offer new models of amorphous Alumina with varying concentrations of Cu having general form (a-Al₂O₃)_1-nCu_n with n = 0, 0.10, 0.20 and 0.30. We study the structural properties of these models. It turns out that Cu atoms cluster because of its less proclivity to diffuse in the highly ionic host a-Al₂O₃. The clustering produces a narrow conducting path for electrical current. To elucidate the electric conduction path, we employ the Kubo-Greenwood formula in a novel space-projected form[1]. We show that the conduction-active component of the network is an interconnected Cu cluster.

[1] K. Prasai, KN. Subedi, K. Ferris, P. Biswas and DA. Drabold, physica status solidi(RRL) 12, 1800238(2018)