Thin film transistor device

1. A thin film transistor device including first and second thin film transistors adjacent to each other in a predetermined direction, the thin film transistor device comprising:

a semiconductor layer;

a gate electrode including first and second gate electrode portions that are spaced from each other in the predetermined direction and form part of the first and second thin film transistors and a conductive portion that electrically connects the first and second gate electrode portions to each other;

a shared electrode positioned between the first and second gate electrode portions and forming part of the first and second thin film transistors; and

first and second electrodes positioned opposite to the shared electrode with respect to the respective first and second gate electrode portions and forming part of the first and second thin film transistors, wherein

the semiconductor layer includes:

a first semiconductor layer portion at least having a first channel region opposed to the first gate electrode portion and a pair of first contact regions formed with the first channel region therebetween in the predetermined direction and doped with an N-type impurity, one of the first contact regions electrically connected with the shared electrode, while the other electrically connected with the first electrode, the first semiconductor layer portion forming part of the first thin film transistor; and

a second semiconductor layer portion at least having a second channel region opposed to the second gate electrode portion and a pair of second contact regions formed with the second channel region therebetween in the predetermined direction and doped with a P-type impurity, one of the second contact regions electrically connected with the shared electrode, while the other electrically connected with the second electrode, the second semiconductor layer portion forming part of the second thin film transistor, wherein

the ones of the first and second contact regions are partially disposed alternately and adjacently in a direction intersecting with the predetermined direction.

2. The thin film transistor device according to claim 1 , wherein

the ones of the first and second contact regions include:

first and second strip-shaped joint portions coupled with the respective first and second channel regions; and

first and second protruding portions protruding from the respective first and second joint portions, wherein

the first and second protruding portions are disposed alternately in the intersecting direction.

3. The thin film transistor device according to claim 1 , wherein the N-type impurity is phosphorus.

4. The thin film transistor device according to claim 1 , wherein the P-type impurity is boron.

5. The thin film transistor device according to claim 1 , wherein the first and second thin film transistors form a CMOS circuit.