Abstract

The dynamic response of hydrogenated amorphous silicon (a-Si:H) thin-film transistor (TFT) and amorphous In-Ga-Zn-O (a-IGZO) TFT are compared. We study the storage capacitor $(C_{\rm st})$ charging characteristics by applying gate and data voltage waveforms corresponding to ultra-high definition (UHD) active-matrix liquid crystal displays (AM-LCDs). We show that the charging behavior of the a-Si:H TFT is insufficient for UHD AM-LCDs and that the a-IGZO TFT is capable of supporting at least 8 K $\times$ 4 K display resolution at 480 Hz. The impact of $C_{\rm st}$ and gate voltage falling edge $(t_{\rm FE})$ on feedthrough voltage $(\Delta V_{\rm P})$ is investigated. Because of higher mobility of the a-IGZO TFT, it is possible to reduce $\Delta V_{\rm P}$ by mitigating channel charge redistribution with non-abrupt $t_{\rm FE}$ . The a-IGZO TFT shows no drawbacks in terms of $\Delta V_{\rm P}$ when compared to the a-Si:H TFT. In addition, a larger $C_{\rm st}$ can be used in combination with the a-IGZO TFT to reduce $\Delta V_{\rm P}$ with minimal impact on its charging behavior. Gate overdrive operation is also evaluated for the a-IGZO TFT, which may improve charging characteristics with no adverse effects on $\Delta V_{\rm P}$ . Our results show that the a-IGZO TFT is a suitable technology for UHD high-frame rate AM-LCDs.

© 2015 IEEE

PDF Article

References

You do not have subscription access to this journal. Citation lists with outbound citation links are available to subscribers only. You may subscribe either as an OSA member, or as an authorized user of your institution.

Contact your librarian or system administrator
or
Login to access OSA Member Subscription

Cited By

You do not have subscription access to this journal. Cited by links are available to subscribers only. You may subscribe either as an OSA member, or as an authorized user of your institution.

Contact your librarian or system administrator
or
Login to access OSA Member Subscription