Purification and densification of Ir by hydrometallurgical combined with powder metallurgical process

This work shows a detailed investigation on the purification and densification of iridium (Ir) targets, which are critical for various electronic components, particularly as electrode materials in solid state disks (SSDs). The objective was to enhance the purity and density of Ir targets by minimizing the presence of alkali, transition, and radioactive metals that degrade the quality of metal-oxide-semiconductor interfaces. The methodology involved a combined hydrometallurgical and powder metallurgical process, where the microstructure of Ir particles was analyzed at different temperatures, revealing significant insights into atom migration and particle growth. Results indicated that at elevated temperatures, surface diffusion of Ir atoms occurred, leading to a reduction in nanopore size and the overall particle density increased as gaps between particles were eliminated. The microstructural analysis correlated with BET surface area measurements, showcasing a substantial decrease in surface area to 0.2541 m²/g as particle size increased. The findings contribute to the understanding of the thermal decomposition mechanism of Ir precursor particles and the subsequent physicochemical transformations, which can significantly impact the performance of Ir-based electronic devices.