In this paper, we have compared amorphous InGaZnO (a-IGZO) thin-film transistor (TFT) with the nano-crystalline embedded-IGZO (Nc-embedded-IGZO) TFT fabricated by solid-phase crystallization (SPC) technique. The field effect mobility (μFE) of Nc-embedded-IGZO TFT was 2.37 cm2/Vs and the subthreshold slope (S-factor) was 0.83 V/decade, which showed lower performance than those of a-IGZO TFT (μFE of a-IGZO was 9.67 cm2/Vs and S-factor was 0.19 V/decade). This results originated from generation of oxygen vacancies in oxide semiconductor and interface between gate insulator and semiconductor due to high temperature annealing process. However, the threshold voltage shift (△V(TH)) of Nc-embedded-IGZO TFT was 0.5 V, which showed 1 V less shift than that of a-IGZO TFT under constant current stress during 10(5) s. This was because there were additionally less increase of interface trap charges in Nc-embedded-IGZO TFT than a-IGZO TFT.
