Optoelectronic properties of coexisting InGaZnO4 structures

Indium gallium zinc oxides (IGZO) have been developed for thin-film transistor technologies. In this work, we analyze the fundamental properties of crystalline InGaZnO4, considering all possible Ga/Zn atomic distribution patterns. Using the hybrid Hartree-Fock density functional approach, the most stable configurations are identified. The simulations reveal that the considered configurations are indirect band-gap semiconductors with highly dispersive conduction bands (CB) and very flat valence bands (VB). Thereby, the electron effective masses are light, contrary to the heavy hole effective masses. This implies a good electron mobility and suppressed hole mobility, and consequently a low off-state current that minimizes the power consumption in future InGaZnO4-based transistors. Coexistence of different configurations is not an issue for InGaZnO4 since they all present very similar optoelectronic properties.

Automated summary

In this study, the fundamental properties of crystalline InGaZnO4 were analyzed, identifying the most stable Ga/Zn atomic distribution patterns and revealing its characteristics as an indirect band-gap semiconductor. The material exhibits good electron mobility and suppressed hole mobility, resulting in lower power consumption in future InGaZnO4-based transistors.