E Beam Registration Marks in Planar Metal Insulator Structures
Original Publication Date: 1978-Sep-01
Included in the Prior Art Database: 2005-Feb-21
The polyimide planar process (U. S. Patent 3,985,597) is a multilevel interconnection process which produces a planar structure at every level. A via stud is used in place of the standard etched via, so that even at this level, the planarity continues. Under these circumstances, there is no topology in the registration area for use with electron (E)-beam alignment tools.