Microstructural evolution and phase formation mechanisms in sintered SnO2/In2O3 ceramics

This study investigates ultra-high-density sintered indium tin oxide (ITO) target material and elucidates the mechanisms of SnO 2 solid solution formation and precipitation during sintering. Consequently, it reveals the phase-transition mechanism within the ITO target material. The results indicate that Sn atoms undergo dissolution into the In 2 O 3 phase, forming (In, Sn) 2 O 3 nanoparticles dispersed within a matrix of Sn-deficient In 2 O 3 grains. As Sn concentration increases, In 4 Sn 3 O[Formula: see text]-type precipitates gradually form. Notably, several of these In 4 Sn 3 O[Formula: see text]-type phases precipitate at grain boundaries. Furthermore, a minor fraction of In 4 Sn 3 O[Formula: see text]-type phases, exhibiting a coplanar orientation with the In 2 O 3 -type matrix phase, are distributed within the matrix grains. These conclusions disclose the microstructural mechanism of the ITO target material, providing a novel perspective for the optimization of ITO.