US 12,266,605 B2
Top via interconnects with line wiggling prevention
Tao Li, Slingerlands, NY (US); Ruilong Xie, Niskayuna, NY (US); Tsung-Sheng Kang, Ballston Lake, NY (US); and Chih-Chao Yang, Glenmont, NY (US)
Assigned to International Business Machines Corporation, Armonk, NY (US)
Filed by International Business Machines Corporation, Armonk, NY (US)
Filed on Sep. 28, 2021, as Appl. No. 17/487,693.
Prior Publication US 2023/0102662 A1, Mar. 30, 2023
Int. Cl. H01L 23/528 (2006.01); H01L 21/768 (2006.01); H01L 23/532 (2006.01)
CPC H01L 23/5283 (2013.01) [H01L 21/76834 (2013.01); H01L 21/76877 (2013.01); H01L 23/53266 (2013.01)] 20 Claims
OG exemplary drawing
 
1. A method comprising:
forming a metal line on a bottom liner, a sacrificial hardmask on a top surface of the metal line, wherein:
the bottom liner is of a different material than the metal line;
a bottom surface of the metal line is directly on a top surface of the bottom liner;
the metal line is tapered such that a width of the bottom surface of the metal line is greater than a width of a top surface of the metal line; and
the bottom liner contacts the metal line only on the bottom surface of the metal line;
selectively removing portions of the sacrificial hardmask that do not correspond a desired location of a top via; and
replacing the remaining sacrificial hardmask with the top via, wherein:
a bottom surface of the top via is directly on the top surface of the metal line; and
the top via is tapered such that a width of the bottom surface of the top via is greater than a width of a top surface of the top via.