The Influence of Layer Thickness and Deposition Conditions on Structural State of NbN/Cu Multilayer Coatings

Автор(ы) O.V. Sobol′1 , A.A. Andreev2 , A.A. Meylekhov1 , А.А. Postelnyk1 , V.A. Stolbovoy2 , I.M. Ryshchenko1, Yu.Ye. Sagaidashnikov1, Zh.V. Kraievska1
Принадлежность

1National Technical University «Kharkiv Polytechnic Institute», 2, Kyrpychov Str., Kharkiv, 61002, Ukraine,

2National Science Center Kharkov Institute of Physics and Technology, 1, Akademicheskaya Str., Kharkiv, 61108, Ukraine

Е-mail
Выпуск Том 11, Год 2019, Номер 1
Даты Получено 26 декабря 2018; в отредактированной форме 07 февраля 2019; опубликовано online 25 февраля 2019
Ссылка O.V. Sobol′, A.A. Andreev, A.A. Meylekhov, et al., J. Nano- Electron. Phys. 11 No 1, 01003 (2019)
DOI https://doi.org/10.21272/jnep.11(1).01003
PACS Number(s) 64.75.St, 81.07.Bc, 62.25.-g, 61.05.cp, 61.82.Rx
Ключевые слова Vacuum arc, NbN/Cu, Period (2) , Bias potential (2) , Phase composition (3) , Structure (102) , Solid solution (6) .
Аннотация

The influence of the main physical and technological factors of structural engineering (layer thickness, nitrogen atmosphere pressure and bias potential) on the structural-phase state of the NbN/Cu coatings was studied. It was established that with an increase in the thickness of niobium nitride layers from 8 to 40 nm (in the NbN/Cu multilayer composition), the phase composition changes from the metastable d-NbN (cubic crystal lattice, NaCl structural type) to the equilibrium ε-NbN phase with a hexagonal crystal lattice. At low pressure PN = 7·10 – 4 Torr in thin layers (about 8 nm thick), regardless of the Ub, the d-NbN phase is formed. The reason for the stabilization of this phase can be the uniformity of the metallic fcc crystal lattice of the δ-NbN phase with the Cu crystal lattice. As the pressure increases from РN = 7·10 – 4 Torr to 3·10 – 3 Torr, a more equilibrium ε-NbN phase with a hexagonal crystal lattice is formed. An increase in the bias potential during deposition from – 50 V to – 200 V mainly affects the change in the preferred orientation of crystallite growth. In thin layers of the d-NbN phase (about 8 nm), a crystallite texture with the [100] axis is formed. In layers with a thickness of 40-120 nm, crystallites of the e-NbN phase are predominantly formed with a hexagonal (004) plane parallel to the growth plane. At the greatest layer thickness (more than 250 nm), the e-NbN phase crystallites are predominantly formed with a (110) hexagonal lattice plane parallel to the growth plane. The results obtained show great potential for structural engineering in niobium nitride when it is used as a constituent layer of the NbN/Cu multilayer periodic system.

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