Abstract: A thin film transistor includes a substrate, a semiconductor layer, a gate insulating layer, a gate, a source and a drain. The semiconductor layer is located above the substrate. The gate insulating layer is located above the semiconductor layer. The gate is located above the gate insulating layer and overlapping with the semiconductor layer. The gate includes a first portion, a second portion and a third portion. The first portion is extending along the surface of the gate insulating layer and directly in contact with the gate insulating layer. The second portion is separated from the gate insulating layer. Taking the surface of the gate insulating layer as a reference, the top surface of the second portion is higher than the top surface of the first portion. The third portion connects the first portion to the second portion. The source and the drain are electrically connected to the semiconductor layer.

Abstract: An indexing apparatus includes a casing, an indexing unit, a gripping unit, a dynamic unit and a driving unit. The indexing unit includes a connecting rod journalled in the casing and having a top portion extending out of the casing, an indexing disc sleeved rigidly on the connecting rod, and several circumferentially equidistant limiting devices provided along the periphery of the indexing disc. The gripping unit slides along the periphery of the indexing disc and can engage with one of the limiting devices so as to prevent the gripping unit from sliding relative to the indexing disc. The dynamic unit supplies power to the indexing unit. The driving unit transfers motion of the dynamic unit to the indexing unit so as to rotate the indexing disc. In a case where the gripping unit is engaged with one of the limiting devices, the movement of the dynamic unit disengages the gripping unit from the limiting device so as to rotate the indexing disc until the gripping unit engages with the next limiting device.