FFS Array Substrate Opening Drain Contact Hole

The patent merges the drain contact hole formation with the pixel electrode opening formation process. The pixel electrode is directly formed to expose the drain electrode through the same opening in the insulating layer, eliminating the need for a separate drain contact hole. This integration allows the electrical connection function and the light transmission function to share the same structural space, thereby resolving the contradiction between achieving reliable electrical connection and maintaining sufficient opening region.

The patent extracts and eliminates the black matrix component from the structure. By directly forming the pixel electrode to expose the drain electrode without creating a separate drain contact hole, the condition that would require black matrix coverage is removed entirely. This extraction of the problematic structural element prevents liquid crystal disclination while simultaneously preserving the opening region and transmittance, as no black matrix is needed to cover a non-existent separate contact hole.

The patent maintains the photosensitive photo acryl layer and assigns it multiple functions: it serves as the insulating layer, as the layer to be opened for pixel electrode formation, and as a parasitic capacitance reduction layer. By making this single layer multi-functional, the patent avoids the need to add additional layers or complex fabrication steps, thereby maintaining fabrication simplicity while simultaneously reducing parasitic capacitance through the preserved photo acryl layer.