High-performance Semitransparent a-InGaZnO4 Thin-film Transistors Using Thin Al Electrodes

We investigate the feasibility of a 10-nm-thick semitransparent layer of Al as gate electrodes, instead of a conducting oxide, for bottom-gate-type amorphous iridium gallium zinc oxide thin-film transistors (a-IGZO TFTs). Good adhesion with glass and plastic substrates is reported for 10-nm-thick Al-gate electrodes, with a sheet resistance of 32 Omega/square. The described semitransparent a-IGZO TFT also shows about a 70%-transmittance. A device operating at low voltage, a saturation mobility of 4.45 cm(2)/V s, a subthreshold swing of 1.06 V/decade, an off-current of about 10(-11) A, and an on-off ratio of 10(7) at an operating gate voltage of 5 V are reported.