Growth of epitaxial iron nitride ultrathin film on zinc-blende gallium nitride

Abstract

The authors report the growth of iron nitride on zinc-blende gallium nitride using molecular beam epitaxy. First, zinc-blende GaN is grown on a magnesium oxide substrate having ͑001͒ orientation; second, an ultrathin layer of FeN is grown on top of the GaN layer. In situ reflection high-energy electron diffraction is used to monitor the surface during growth, and a well-defined epitaxial relationship is observed. Cross-sectional transmission electron microscopy is used to reveal the epitaxial continuity at the gallium nitride-iron nitride interface. Surface morphology of the iron nitride, similar to yet different from that of the GaN substrate, can be described as plateau valley. The FeN chemical stoichiometry is probed using both bulk and surface sensitive methods, and the magnetic properties of the sample are revealed.

In-situ growth of iron mononitride thin films studied using x-ray absorption spectroscopy and nuclear resonant scattering

“…This peak can be assigned to FeN(111) and the LP comes out to be 4.45Å. Generally, the LP of FeN films has been found anywhere between 4.3 to 4.55Å and when FeN films are deposited at low T s (< 400 K), LP ≈ 4.5Å [32,34,75] and at high T s , LP reduces to about 4.3Å [47,75]. Therefore, from our XRD measurements, we can confirm the formation of mononitride FeN phase.…”

“…FeN compounds were extensively studied by Schaff et al [23][24][25][26] in late 1990s. Subsequently, FeN thin films were synthesized using ion beam sputtering [27], dc/rf magnetron sputtering [28][29][30][31][32][33][34][35][36][37][38], pulsed laser deposition (PLD) [39][40][41][42], high power impulse magnetron sputtering [43], nitrogen plasma assisted molecular beam epitaxy (MBE) [44][45][46][47][48] and very recently under HPHT [12,16,[49][50][51]. From applications points of view, the mononitride FeN is also very interesting as its oxidation resistance makes it a effective catalyst in chemical reactions [52,53], it can be used as a precursor to yield magnetic phases in a controlled way [38,44,54,55] and also in biomedical applications [17].…”

“…Jouanny et al [32] prepared FeN thin films having LP ≈ 4.5Å using sputtering at 373 K and from their zero-field-cooled and field-cooled (1 T) magnetization measurements they could not find the presence of any magnetic order. J. Pak et al [47] studied the growth behavior of epitaxial FeN thin films deposited using N plasma assisted MBE and from their in-situ reflection high energy electron diffraction (RHEED) measurements they found that the LP of ultrathin FeN films was about 4.52Å. Up to about 53 monolayers (ML), the LP of FeN films remained at this value but for a 140 ML thick (≈ 60 nm) FeN film, the LP reduced to 4.32Å.…”

X-ray absorption spectroscopy study of cobalt mononitride thin films

“…From recent experimental works, it can be observed that FeN crystalizes in the ZB-type structure only (under ambient pressure and temperature) and the existence of the RS-type FeN has been questioned in several recent works [34][35][36]. Though theoretical works predict both ZBand RS-type structures for FeN and CoN, but under ambient temperature and pressure, the ZB-type structure is preferred [21].…”

Study of Structural &amp; Magnetic Properties of CoN Thin Films

“…Among the late TMMN, FeN is the most studied compound yet its structural and magnetic ground state is still debated [25,26]. From recent experimental works, it can be observed that FeN crystalizes in the ZB-type structure only (under ambient pressure and temperature) and the existence of the RS-type FeN has been questioned in several works [27][28][29]. Though theoretical works predict both ZB and RS-type structures for FeN and CoN but under ambient temperature and pressure, the ZB-type structure is preferred [21].…”