HADS products typically use organic film materials to reduce parasitic capacitance for high PPI display. In this paper, the process optimization of the common electrode ITO and the data line short-circuit defect of the organic film product designed by the top ITO for the pixel electrode (Pixel Top) is improved. Firstly, the mechanism of DCS failure of HADS organic film products is analyzed by microscope and Focused Ion beam. A ‘one-step etch’ process variation improvement scheme which skips the PVX1 etch step and retains PVX1 until PVX2 etch is proposed. Aiming at the problem of PVX1 layer undercut of TFT gate via hole in the new process verification experiment, the PVX1 film quality is improved by adjusting the PECVD film formation parameters. The optimum film formation condition is selected to further adjust the dry etch process, and an excellent slope angle is obtained. On the TFT substrate which uses the optimized one-step etching process, the PVX1 slope angle of gate via hole is less than 40° and there is no significant step between the PVX1 and the GI layer, and there is no obvious step between the PVX1 and the GI layer. The mass production rate of the DCS caused by the absence of the organic film is reduced to zero. By optimizing the process, the product defect rate is reduced while the process steps are reduced and the production capacity is increased.