Patent ID: 7189603

Claim:
A manufacture method for a thin film transistor substrate, comprising the steps of: (a) forming a semiconductor layer on a substrate, said semiconductor layer having a threshold voltage suitable for an n-channel transistor; (b) patterning said semiconductor layer into island areas by using a first mask to define an area of a pixel driving n-channel transistor with LDD regions, an area of a CMOS n-channel transistor and an area of a CMOS p-channel transistor; (c) forming a gate insulating film and a first gate electrode layer to cover said semiconductor layer patterned to form the island areas; (d) patterning said first gate electrode layer by using a second mask to form a first gate electrode layer having an opening in the CMOS p-channel transistor area; (e) by using said first gate electrode layer as a mask, implanting n-type impurity ions into the CMOS p-channel transistor area in the opening to set a threshold voltage suitable for the CMOS p-channel transistor; (f) after said step (e), forming a second gate electrode layer covering said first gate electrode layer; (g) etching said second gate electrode layer by using a third mask to form second gate electrodes having a gate electrode shape; (h) by using said second gate electrodes and said first gate electrode layer as a mask, implanting high concentration p-type impurity ions into the CMOS p-channel transistor area to form high impurity concentration source/drain regions; (i) by using said second gate electrodes as a mask, etching said first gate electrode layer to form gate electrodes of the n-channel transistors; (j) by using a fourth mask covering the CMOS p-channel transistor area and the LDD regions in the area of the n-channel transistor with the LDD regions, implanting high concentration n-type impurity ions to form high impurity concentration source/drain regions of the n-channel transistors; and (k) implanting low concentration n-type impurity ions to form the LDD regions in the area of the n-channel transistor with the LDD regions.