Production of a trench capacitor for a semiconductor memory cell comprises forming a trench in a substrate using a hard mask, forming a capacitor dielectric, insulating collar and conducting filler in trench regions, and further processing

摘要

Production of a trench capacitor comprises forming a trench (5) in a substrate (1) using a hard mask (2, 3), forming a capacitor dielectric (30), an insulating collar (10) and an electrically conducting filler (20, 40) in the upper and lower trench regions, forming a liner on the hard mask and in the trench, implanting impurity ions into the trench using the hard mask, forming a liner mask to define a contact region and an insulating region of the trench contact, and completing the connecting region (KS) and the insulating region of the trench contact by removing and replacing a part of the filler and/or a part of the collar using the liner mask.