1.5-V-Operation Ultralow Power Circuit of Poly-Si TFTs Fabricated Using the NAOS Method

We have fabricated thin-film transistors (TFTs) and liquid-crystal displays (LCDs) with monolithic drivers on glass substrates and achieved ultralow power consumption by operating with a low power-supply voltage at 3 V. The gate insulator of the TFTs has a stack structure with an ultrathin interfacial SiO2 layer formed by nitric acid oxidation of silicon and a 40-nm-thick SiO2 layer formed by plasma-enhanced chemical vapor deposition. Owing to the TFTs with the thin gate insulator, the driving circuits of the LCDs can be operated at a supply voltage of 1.5 V, which is much lower than that of conventional LCDs of 10-15 V.