Display device, display panel, array substrate and manufacturing method thereof

The invention provides a display device, a display panel, an array substrate and a manufacturing method thereof. The display device comprises a substrate and multiple thin film transistors arranged on the substrate. Each thin film transistor comprises a semiconductor layer, a grid electrode, a source electrode and a drain electrode, wherein the semiconductor layer is arranged on the surface of the substrate, the source electrode and the drain electrode are sequentially arranged on the surface of the semiconductor layer, an insulation layer is arranged between the source electrode and the semiconductor layer, and a planarization layer is arranged between the drain electrode and the source electrode. The source electrode is connected with the semiconductor layer through a first via hole penetrating through the insulation layer, and the drain electrode is connected with the semiconductor layer through second via holes penetrating through the planarization layer and the insulation layer. Due to the fact that the