Manufacturing method of contact hole in semiconductor process

The invention provides a method for manufacturing a contact hole in a semiconductor process. The method comprises the following steps of: S1, depositing an interlayer dielectric layer with a first thickness on the surface of a semiconductor structure; s2, forming a patterned interlayer dielectric layer on the interlayer dielectric layer by using a mask plate of the grid electrode, so that the thickness of the interlayer dielectric layer over the grid electrode is approximately the same as the thickness of the interlayer dielectric layer over the source region and the drain region of the device; s3, forming a source contact hole, a drain contact hole and a gate contact hole in the patterned interlayer dielectric layer, wherein the depth of the source contact hole and the depth of the drain contact hole are approximately the same as the depth of the gate contact hole; s4, filling a transition layer and a conductive metal layer in the contact hole; and S5, planarizing the surface of the interlayer dielectric lay