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  • The growth of self-intercalated Nb1+ x Se2 by molecular beam epitaxy: The effect of processing conditions on the structure and electrical resistivity
Title: The growth of self-intercalated Nb1+ x Se2 by molecular beam epitaxy: The effect of processing conditions on the structure and electrical resistivity
We report on the synthesis of self-intercalated Nb1+xSe2 thin films by molecular beam epitaxy. Nb1+xSe2 is a metal-rich phase of NbSe2 where additional Nb atoms populate the van der Waals gap. The grown thin films are studied as a function of the Se to Nb beam equivalence pressure ratio (BEPR). X-ray photoelectron spectroscopy and x-ray diffraction indicate that BEPRs of 5:1 and greater result in the growth of the Nb1+xSe2 phase and that the amount of intercalation is inversely proportional to the Se to Nb BEPR. Electrical resistivity measurements also show an inverse relationship between BEPR and resistivity in the grown Nb1+xSe2 thin films. A second Nb-Se compound with a stoichiometry of ∼1:1 was synthesized using a Se to Nb BEPR of 2:1; in contrast to the Nb1+xSe2 thin films, this compound did not show evidence of a layered structure.  more » « less
Award ID(s):
1939012
PAR ID:
10489527
Author(s) / Creator(s):
; ; ; ; ; ; ;
Publisher / Repository:
JVSTA
Date Published:
Journal Name:
Journal of Vacuum Science & Technology A
Volume:
41
Issue:
4
ISSN:
0734-2101
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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