Systematic View of CAAC‐IGZO and Other Crystalline IGZO Thin Films

This chapter presents crystalline indium-gallium-zinc oxide (IGZO) thin films that can be formed at lower temperatures and are developed for practical applications and mass production. It focuses on a c-axis-aligned crystalline IGZO (CAAC-IGZO) thin film, which can be formed on an amorphous SiOx film at low temperatures. The chapter deals with the fabrication processes, analysis of the crystal structure and crystal morphology, and the deposition mechanism. It mainly discusses the crystallinity of IGZO thin films deposited by the sputtering method. As an alternative deposition method, PLD is widely used in material research. The chapter explains several features of CAAC-IGZO and some topics including other crystal morphologies. It talks about the various crystal morphologies that IGZO exhibit, for example nanocrystalline, CAAC, polycrystalline, and single-crystal structures. The polycrystalline and single-crystal structures can be distinguished precisely in terms of translational symmetry and the presence or absence of clear grain boundaries.