Thin film transistor and method of making the same

A thin film transistor comprising:

• an insulation substrate
• a first source electrode and a first drain electrode formed on the insulation substrate, a first active layer formed so that it is in contact with the first source electrode and the first drain electrode;
• a common gate electrode formed on a first insulation layer which is on the first source electrode, the first drain electrode and the first active layer;
• a second active layer formed on a second insulation layer which is on the common gate electrode,
• a second source electrode and a second drain electrode formed on the second active layer,
• the first source electrodes are contacted and the first drain electrodes are in contact with the second source and second drain electrodes respectively through an opening formed in the insulation layers which are formed on the upper portion and the lower portion of the common gate electrode.

A thin film transistor comprising:

• an insulation substrate
• a first source electrode and a first drain electrode formed on the insulation substrate, a first active layer formed so that it is in contact with the first source electrode and the first drain electrode;
• a common gate electrode formed on a first insulation layer which is on the first source electrode, the first drain electrode and the first active layer;
• a second active layer formed on a second insulation layer which is on the common gate electrode,
• a second source electrode and a second drain electrode formed on the second active layer,
• the second source and drain electrodes are directly in contact respectively with a selected portion of the first source and first drain electrodes.