Thin film transistor and fabricating method thereof

A fabricating method of a thin film transistor, comprising:

• sequentially forming a channel material layer, an ohmic contact material layer, and a patterned photoresist layer on a substrate;
• patterning the channel material layer and the ohmic contact material layer by using the patterned photoresist layer as a mask, so as to form a channel layer and an ohmic contact layer between the channel layer and the patterned photoresist layer;
• forming a dielectric layer on the patterned photoresist layer, on a sidewall of the channel layer, and on a sidewall of the ohmic contact layer;
• removing the patterned photoresist layer and a portion of the dielectric layer that is in contact with the patterned photoresist layer, so as to expose the ohmic contact layer;
• forming a source and a drain on a portion of the dielectric layer and on a portion of the ohmic contact layer, and removing a portion of the ohmic contact layer that is not covered by the source or the drain;
• forming a gate insulating layer on the substrate, so as to cover the source, the drain, the dielectric layer, and the channel layer;
• and
• forming a gate on the gate insulating layer, wherein the gate is located above the channel layer.

A thin film transistor disposed on a substrate, the thin film transistor comprising:

• a channel layer having an upper surface and a sidewall;
• an ohmic contact layer disposed on a portion of the upper surface of the channel layer;
• a dielectric layer disposed on the sidewall of the channel layer, wherein the dielectric layer and ohmic contact are not overlapped;
• a source and a drain disposed on the ohmic contact layer and on a portion of the dielectric layer, and a portion of the dielectric layer is not covered by the source or the drain;
• a gate disposed above or below the channel layer;
• and
• a gate insulating layer disposed between the gate and the channel layer.