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Title: Surface oxidation of hydrophobic ZnSe for enhanced growth of atomic layer deposited aluminum oxide
The growth of atomic layer deposited (ALD) Al 2 O 3 on planar ZnSe substrates is studied using in situ spectroscopic ellipsometry. An untreated ZnSe surface requires an incubation period of 27 cycles of ALD Al 2 O 3 before film growth is observed. Pretreating the surface with an ultraviolet generated ozone lowers the incubation to 17 cycles, whereas a plasma-enhanced ALD Al 2 O 3 process can further lower the incubation period to 13 cycles. The use of ozone or plasma-activated oxygen species on ZnSe is found to create ZnO and SeO 2 , which are responsible for converting ZnSe from a hydrophobic to a hydrophilic surface. The interfacial layer between Al 2 O 3 and ZnSe is mapped using high-resolution transmission electron microscopy and scanning transmission electron microscopy/energy dispersive spectroscopy. SeO 2 is volatile and leaves a zinc-rich interface, which is 4.3 nm thick for the ultraviolet generated ozone pretreated sample and 2.5 nm for the plasma-enhanced ALD process.  more » « less
Award ID(s):
1908167
PAR ID:
10391986
Author(s) / Creator(s):
; ; ; ; ; ; ;
Date Published:
Journal Name:
Journal of Vacuum Science & Technology A
Volume:
40
Issue:
5
ISSN:
0734-2101
Page Range / eLocation ID:
052402
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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