THIN FILM TRANSISTOR HAVING HIGH ON/OFF CURRENT RATIO

摘要

Disclosed is a thin film transistor having a high on/off current ratio. The disclosed transistor comprises: a gate electrode on a substrate; a first channel above the gate electrode; source and drain electrodes connected to opposite ends of the first channel; and a second channel which is in contact with an upper side of the first channel to be opposite to the gate electrode on the first channel and has higher conductivity than that of the first channel. The second channel is separated from the source and drain electrodes. The gate electrode is formed between the source and drain electrodes to not be overlapped with the source and drain electrodes at the floor plan. According to the present invention, a high electric field is prevented from being formed between the gate electrode and the source and drain electrodes by an offset structure when the thin film transistor is turned off. Therefore, off current can be reduced.