Investigating the influence mechanism of aluminum doping amount on the density and grain size of AZO target through phase-field simulation

Abstract

This study proposes a three-phase model (primary, secondary, and pore phases) utilizing the phase-field method to simulate sintering densification in AZO targets. The impact of secondary phase content and dimensions on the densification of AZO targets was investigated. The findings indicated that the density of the AZO target exhibited an initial increase followed by a subsequent decline with the augmentation of the secondary phase content and size. Conversely, the grain size demonstrated a continuous reduction. The Brook kinetic equation yields activation energies for grain growth of 607.40 kJ/mol, 999.32 kJ/mol, and 1093.20 kJ/mol for 1 wt%, 2 wt%, and 3 wt% Al₂O₃, respectively. Furthermore, the viability of the model was corroborated through experimentation. Based on the simulation outcomes, AZO targets doped with 2 wt% Al₂O₃ achieved 99.78 % densification, an average grain size of 3.92 μm, and a resistivity of 1.38 mΩ·cm.