Semiconductor metal-oxide thin-film transistors for display

Due to their process requirements being similar to the making of amorphous silicon thin-film transistors (TFTs) and their relatively higher field-effect mobility (μFE), metal-oxide (MO) TFTs are being deployed in the construction of active-matrix flat-panel displays (FPDs). In this chapter, the brief status and principle of active-matrix (AM) FPDs are introduced within comparing the MO TFTs with other silicon based competing technologies. In the ensuing section, the major issues of TFT architectures and channel material are addressed. Compared to the early state of developing MO TFTs, the major manufactories of MO TFTs in the display industry locate indium–gallium–zinc oxide (IGZO) as their core material. The latest practical IGZO TFTs reveal good characteristics in both AM liquid-crystal displays (LCD) and AM organic light-emitting diode (OLED) displays. Considering commonly n-type depletion mode and reliability issues of IGZO TFTs, specific circuits design for both pixels and scan drivers in AMLCD and AMOLED are introduced in the third section. Novel micro-LED displays emerging and new materials for wide-bandgap and p-type MO TFTs are anticipated to boost the growth of MO TFTs involving in the FPD industry.