Effect of the nitrogen-argon gas mixtures on the superconductivity properties of reactively sputtered molybdenum nitride thin films

Haberkorn, N.; Bengió, S.; Suárez, S.; Pérez, Pablo Daniel; Sirena, M.; Guimpel, J.

doi:10.1016/j.matlet.2017.12.045

Cited by 26 publications

(22 citation statements)

References 25 publications

(24 reference statements)

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The composition MoN (1.00±0.05) was observed for pristine and annealed specimens. As-grown MoN thin films using a N 2 /(Ar+N 2 )= 0.5 mixture are mostly amorphous (a little reflection attributed to γ Mo 2 N is observed) [18]. The crystallization of δ-MoN after thermal annealing at temperatures above 600 °C was confirmed by XRD (see Fig.…”

Section: Resultsmentioning

confidence: 78%

“…Moreover, superconductivity has been observed for films with thicknesses of a few nanometers [14,15,17]. Recently, we have reported that the chemical concentration and T c for Mo-N thin films grown at room temperature by reactive sputtering can be modified by changing the Ar:N 2 ratio [18]. Films grown with N 2 /(Ar+N 2 ) < 0.4 mixtures are superconducting with nanocrystalline γ-Mo 2 N phase.…”

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Synthesis of nanocrystalline δ-MoN by thermal annealing of amorphous thin films grown on (100) Si by reactive sputtering at room temperature

et al. 2018

Self Cite

View full text Add to dashboard Cite

We report on the synthesis and characterization of nanocrystalline δ-MoN by crystallization of amorphous thin films grown on (100) Si by reactive sputtering at room temperature.Films with chemical composition MoN were grown using a deposition pressure of 5mTorr with a reactive mixture of Ar/(Ar+N 2 )=0.5. The as-grown films display mostly amorphous structure. Nanocrystalline δ-MoN phase is obtained after annealing at temperatures above 600 °C. The superconducting critical temperature T c depends on film thickness. Thick films (170 nm) annealed at 700 °C for 30 min display a T c = 11.2 K (close to the one reported for bulk specimens: 13 K), which is gradually suppressed to 7.2 K for 40 nm thick δ-MoN films. Our results provide a simple method to synthesize superconducting nitride thin films on silicon wafers with T c above the ones observed for conventional superconductors such as Nb.

show abstract

Section: Resultsmentioning

confidence: 78%

Section: Introductionmentioning

confidence: 99%

Synthesis of nanocrystalline δ-MoN by thermal annealing of amorphous thin films grown on (100) Si by reactive sputtering at room temperature

et al. 2018

Self Cite

View full text Add to dashboard Cite

show abstract

“…Figure phase [9]. The shift to lower angles of both reflections respect to tabulated values can be related to interstitial nitrogen [15]. The D value is ≈ 12 nm.…”

Section: Methodsmentioning

confidence: 73%

Superconductivity in nanocrystalline tungsten thin films growth by sputtering in a nitrogen-argon mixture

Hofer

Haberkorn

2019

Thin Solid Films

Self Cite

View full text Add to dashboard Cite

We report on the structural and superconducting properties of nanocrystalline tungsten thin films growth by sputtering at room temperature with an N 2 :Ar mixture (N 2 from 3% to 50%). The crystalline phases were identified by comparing as-grown and thermal annealed thin films. For N 2 /(Ar+N 2 ) mixtures between 3 and 10 %, the films display nanocrystalline β-W phase.Coexistence of β-W and W 2 N phases are observed for gas mixtures with N 2 between 20 % and 40%. A detailed study of the superconducting properties as function of the thickness was performed for W films growth with 8 % N 2 mixtures. For this concentration, the nitrogen atoms increase the disorder at the nanoscale reducing the grain size and avoiding the crystallization of α-W. The superconducting critical temperature (T c = 4.7 K) is thickness independent for films thicker than ~ 17 nm. Below this thickness, the T c value decreases systematically being 3.1 K for 4 nm thick films. Our study provides a simple method for the fabrication of nanocrystalline β-W thin films with potential applications in superconducting devices.

show abstract

“…This fact is in agreement with the presence of oxygen even for cleaned surfaces, as we mentioned above. It is important to note that the XPS spectra for the -Mo 2 N phase is weakly affected by small changes in chemical composition [28]. Since no crystalline structure changes are observed as a function of film thickness, no changes are expected in the XPS spectra.…”

Section: A Structural and Chemical Composition Analysis Of The Filmsmentioning

confidence: 99%

Thickness dependence of the superconducting properties of γ- Mo2N thin films on Si (001) grown by DC sputtering at room temperature

Haberkorn

Bengió

Troiani

et al. 2018

Materials Chemistry and Physics

Self Cite

View full text Add to dashboard Cite

We study the crystalline structure and superconducting properties of -Mo 2 N thin films grown by reactive DC sputtering on AlN buffered Si (001) substrates. The films were grown at room temperature. The microstructure of the films, which was studied by X-ray diffraction and transmission electron microscopy, shows a single-phase with nanometric grains textured along the (200) direction. The films exhibit highly uniform thickness in areas larger than 20 x 20 m 2. The superconducting critical temperature T c is suppressed from 6.6 K to ≈ 3.0 K when the thickness decreases from 40 nm to 5 nm. The residual-resistivity ratio is slightly smaller than 1 for all the films, which indicates very short electronic mean free path. The films are in the superconducting dirty limit with upper critical field H c2 (0) ≈ 12 T for films with thickness of 40 nm, and 9 T for films with thickness of 10 nm. In addition, from the critical current densities J c in the vortex-free state, we estimate a penetration depth (0) ≈ (800  50) nm and a thermodynamic critical field H c (0) = (500  80 Oe).

show abstract

Effect of the nitrogen-argon gas mixtures on the superconductivity properties of reactively sputtered molybdenum nitride thin films

Cited by 26 publications

References 25 publications

Synthesis of nanocrystalline δ-MoN by thermal annealing of amorphous thin films grown on (100) Si by reactive sputtering at room temperature

Synthesis of nanocrystalline δ-MoN by thermal annealing of amorphous thin films grown on (100) Si by reactive sputtering at room temperature

Superconductivity in nanocrystalline tungsten thin films growth by sputtering in a nitrogen-argon mixture

Thickness dependence of the superconducting properties of γ- Mo2N thin films on Si (001) grown by DC sputtering at room temperature

Contact Info

Product

Resources

About