Method of making a contact hole to a doped region

Abstract

Abstract A doped region (2) is made in a substrate (1) in such a way that it is bounded by insulating regions (5) at least at the surface of the substrate (1). An undoped silicon layer (6) is deposited over the entire surface. A doped region (61) is selectively produced in the silicon layer (6) and reliably overlaps the region for the contact hole (via) (10). Undoped parts of the silicon layer (6) are removed selectively with respect to the doped regions (61). An insulating layer (9) in which a contact hole (10) is opened selectively with respect to the doped region (61) of the silicon layer (6) by anisotropic etching is produced over the entire surface. The method is suitable for making space-saving bit-line contacts in DRAMs having p-channel MOSFETs in the cell array. <IMAGE>

Inventors

• 👤 Josef Dr. Winnerl
• 👤 Walter Dipl.-Phys. Neumüller

Bibliographic Details