Low Threshold Voltage and High Drive Current Poly-Silicon Thin Film Transistors Using Aluminum Metal Gate and HfLaO Dielectric

We have integrated a Metal gate into Low temperature Poly-Silicon(LTPS) thin-film transistors (TFTs) with highκ gate dielectric. We used Aluminum for metal gate, and we used HfLaO for high-κ gate dielectric on LTPS. We got high drive current, low threshold voltage and low sub-threshold slop to improve the performance of device obviously. It also achieved high on/off ratio and high gate breakdown electric field. The excellent performances mentioned above are related closely to gate dielectric. We used HfLaO for high-κ dielectric and it can product high density gate capacitor and less EOT. This kind of device is different from other common devices because it is not necessary to apply passive treatment or specific process of crystallization. We only used furnace to crystallize.