Method for forming overlay verniers for semiconductor devices

摘要

The present invention discloses a method for forming an overlay vernier that can prevents deformation of the mother vernier. The method comprises the steps of: forming a planarization film on a wafer where a predetermined basic substructure has been formed; etching the planarization film to expose a predetermined region of a scribe line of the wafer where the overlay vernier will be formed; depositing a first polysilicon layer on the planarization film and the exposed wafer region; polishing the first polysilicon layer until the surface of the planarization film is exposed; forming an interlayer insulating film on the planarization film and the remained first polysilicon layer; etching the interlayer insulating film to expose a region of the first polysilicon layer where the mother vernier of the overlay vernier will be formed; depositing a second polysilicon layer on the interlayer insulating film and the exposed first polysilicon layer; and patterning the second polysilicon layer to form the mother vernier.