Preliminary study for deposition of Mg₂Si thin films with high-power impulse magnetron sputtering

Abstract

We report the preliminary results of the deposition of Mg₂Si thin films using high-power impulse magnetron sputtering (HiPIMS). HiPIMS operates using deposition equipment similar to DC magnetron sputtering but with repetitive electric current pulses to achieve higher current densities, generating ionized sputtered particles. The HiPIMS method was used to deposit Mg₂Si thin films on unheated silicon and sapphire substrates using a Mg₂Si sintered target, which were subjected to SEM-EDS characterization. The peak power density was evaluated to be 0.5 kW/cm² or less, which was considered to exceed the DC sputtering regime. The film thickness was evaluated to be approximately 200 nm after 30 min of deposition. The composition ratio of Mg to Si on the film was approximately 2:1, which was close to that of the target. A crack-free surface morphology was achieved by applying a substrate bias voltage of 200 V.