Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Low temperature (Ts/Tm < 0.1) epitaxial growth of HfN/MgO(001) via
  reactive HiPIMS with metal-ion synchronized substrate bias   Low-temperature epitaxial growth of refractory transition-metal nitride thin
films by means of physical vapor deposition has been a recurring theme in
advanced thin-film technology for several years. In the present study,
150-nm-thick epitaxial HfN layers are grown on MgO(001) by reactive
high-impulse magnetron sputtering (HiPIMS) with no external substrate heating.
Maximum film growth temperatures Ts due to plasma heating range from 70-150
{\deg}C, corresponding to Ts/Tm = 0.10-0.12 (in which Tm is the HfN melting
point in K). During HiPIMS, gas and sputtered-metal ion fluxes incident at the
growing film surface are separated in time due to strong gas rarefaction and
the transition to a metal-ion dominated plasma. In the present experiments, a
negative bias of 100 V is applied to the substrate, either continuously during
the entire deposition or synchronized with the metal-rich portion of the ion
flux. Two different sputtering-gas mixtures, Ar/N2 and Kr/N2, are employed in
order to probe effects associated with the noble-gas mass and ionization
potential. The combination of x-ray diffraction, high-resolution
reciprocal-lattice maps, and high-resolution cross-sectional transmission
electron microscopy analyses establish that all HfN films have a cube-on-cube
orientational relationship with the substrate, i.e., [001]HfN||[001]MgO and
(100)HfN||(100)MgO. Layers grown with continuous substrate bias, in either
Ar/N2 or Kr/N2, exhibit a relatively high mosaicity and a high concentration of
trapped inert gas. In distinct contrast, layers grown in Kr/N2 with the
substrate bias synchronized to the metal-ion-rich portion of HiPIMS pulses,
have much lower mosaicity, no measurable inert-gas incorporation, and a
hardness of 25.7 GPa, in good agreement with results for epitaxial HfN(001)
layers grown at Ts = 650 C (Ts/Tm = 0.26).

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The categories of this paper are: hep-lat
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The categories of this paper are: acc-phys
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The categories of this paper are: hep-ph
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The categories of this paper are: nucl-th
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The categories of this paper are: patt-sol
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The categories of this paper are: cmp-lg
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The categories of this paper are: q-alg
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The categories of this paper are: quant-ph
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The categories of this paper are: alg-geom
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The categories of this paper are: physics
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The categories of this paper are: eess
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The categories of this paper are: econ
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The categories of this paper are: plasm-ph
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The categories of this paper are: cs
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The categories of this paper are: astro-ph
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The categories of this paper are: solv-int