| Summary: | The memory characteristics of a flash memory device using c-axis aligned crystal indium gallium zinc oxide (CAAC-IGZO) thin film as a channel material were demonstrated. The CAAC-IGZO thin films can replace the current poly-silicon channel, which has reduced mobility because of grain-induced degradation. The CAAC-IGZO thin films were achieved using a tantalum catalyst layer with annealing. A thin film transistor (TFT) with SiO<sub>2</sub>/Si<sub>3</sub>N<sub>4</sub>/Al<sub>2</sub>O<sub>3</sub> and CAAC-IGZO thin films, where Al<sub>2</sub>O<sub>3</sub> was used for the tunneling layer, was evaluated for a flash memory application and compared with a device using an amorphous IGZO (<i>a</i>-IGZO) channel. A source and drain using indium-tin oxide and aluminum were also evaluated for TFT flash memory devices with crystallized and amorphous channel materials. Compared with the <i>a</i>-IGZO device, higher on-current (I<sub>on</sub>), improved field effect carrier mobility (μ<sub>FE</sub>), a lower body trap (N<sub>ss</sub>), a wider memory window (ΔV<sub>th</sub>), and better retention and endurance characteristics were attained using the CAAC-IGZO device.
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