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Title: Plasma nitridation for atomic layer etching of Ni
Nickel (Ni) and its alloys are important multifunctional materials for the fabrication of integrated circuits, as either the absorber for the extreme ultraviolet lithography masks and/or interconnect metals at the nanometer scale. However, these applications require that Ni to be patterned controllably, selectively, and anisotropically—requirements that can only be met with a plasma based atomic layer etch (ALE) process. In this work, a plasma-thermal ALE approach is developed to pattern Ni, utilizing a nitrogen plasma to form NixN at the surface, formic acid (FA) vapor to selectively remove the NixN layer, and a low-energy Ar+ sputter process to remove carbon residue left by the FA prior to the subsequent nitridation step. This three step ALE process was shown effective to etch Ni with a rate of 1.3 ± 0.17 nm/cycle while maintaining surface smoothness.  more » « less
Award ID(s):
1805112 2212981
PAR ID:
10538847
Author(s) / Creator(s):
; ; ;
Publisher / Repository:
Journal of Vacuum Science and Technology A
Date Published:
Journal Name:
Journal of Vacuum Science & Technology A
Volume:
42
Issue:
2
ISSN:
0734-2101
Page Range / eLocation ID:
022602
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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