Manufacturing methods of display panels and display panels

A manufacturing method of a display panel, comprising following steps:

• providing a substrate;
• forming a semiconductor layer on the substrate, wherein the step of forming the semiconductor layer on the substrate comprises:
• forming a semiconductor sub-layer on the substrate, forming a first sub-ohmic contact layer on the semiconductor sub-layer, and forming a second sub-ohmic contact layer on the first sub-ohmic contact layer;
• wherein a volume flow rate of phosphine for forming the first sub-ohmic contact layer is greater than or equal to 6590 sccm and less than or equal to 12590 sccm, and a volume flow rate of phosphine for forming the second sub-ohmic contact layer is greater than or equal to 21000 sccm and less than or equal to 27000 sccm;
• and wherein the first sub-ohmic contact layer and the second sub-ohmic contact layer form an ohmic contact layer with a thickness greater than or equal to 40 Å and less than or equal to 100 Å;
• forming a source/drain metal layer on the semiconductor layer;
• etching the source/drain metal layer to form a source and a drain, and
• etching the semiconductor layer to remove a part of the ohmic contact layer disposed between the source and the drain, wherein a volume flow rate of chlorine in an etching gas for etching the semiconductor layer is less than 400 sccm.