Thin Film Systems Research Articles

Expanding the applications of the wear-resistant titanium aluminum nitride thin-film to include temperature sensing

This study investigates an approach to temperature sensing by integrating Titanium Aluminum Nitride (TiAlN), originally engineered for wear and corrosion applications, as a temperature sensor within a multilayered thin film system. A nitride multilayer system was developed by physical vapor deposition (PVD) using a single four-target magnetron sputtering chamber; intermediate vacuum interruption steps were employed for masking procedures. The multilayer architecture design aimed to provide the sensor layer with mechanical protection and electrical shielding. Structural and electrical characterization of the TiAlN single layer revealed semiconductor behavior and stable electrical resistance up to 750 °C, with minimal signal stabilization requirements. Despite the higher Al content, the TiAlN temperature sensor exhibited a cubic crystal structure characterized by diffuse nanolayers, resulting from a two-fold rotational deposition and target configuration. A detailed examination of the multilayer system cross-section containing the TiAlN sensor was conducted using scanning transmission electron microscopy (STEM). The analysis revealed its columnar morphology with the presence of typical PVD growth defects, including voids and droplets. While the presence of these defects may impact the electrical characteristics of the sensor, the selected experimental conditions effectively maintained the structural integrity of the multilayer system despite the vacuum interruptions caused by masking procedures. Validation experiments confirmed the functionality of the multilayer system for temperature measurements up to 400 °C. The signal acquisition system addressed room temperature resistance variations and low sensitivity (thermistor coefficient ∼100 K), resulting in a measured error of approximately 6%. This study demonstrates promising results of TiAlN as a temperature sensor within a multilayered system, expanding its range of potential applications.

High‐Throughput Study of the Phase Constitution of the Thin Film System Mg–Mn–Al–O

The increasing importance of recycling makes the recovery of valuable elements from slags interesting. The concept of engineered artificial minerals aims at the formation of phase(s) with a high content of the to‐be‐recovered element(s) from slags of pyrometallurgical recycling processes. For this, understanding the phase constitution of the slag systems, such as the spinel‐forming subsystem Mg–Mn–Al–O from Li‐ion battery recycling, is of great importance. Herein, the phase constitution is investigated using a thin film materials library (ML) that covers the composition space (Mg14−69Mn11−38Al14−74)Ox. High‐throughput energy‐dispersive X‐ray spectroscopy and X‐ray diffraction confirm the formation of the spinel solid solution phase for a wide composition space. The Mn oxidation state is shown to be a mixture of Mn2+ and Mn3+ by analyzing Mn 2p3/2 spectra from X‐ray photoelectron spectroscopy. For one measurement area of the ML containing equal atomic amounts of Mg, Mn, and Al, transmission electron microscopy shows columnar spinel grains with Mg, Mn, and Al evenly distributed. Based on these results, it is suggested that the high likelihood of spinel formation in slags can be influenced by controlling the Mn oxidation state to allow the formation of desirable engineered artificial minerals for Li recovery.

Magneto-ionic modulation of the interlayer exchange interaction in synthetic antiferromagnets

The electric-field control of magnetism is a highly promising and potentially effective approach for realizing energy-efficient applications. Recent interest has focused on the magneto-ionic effect in synthetic antiferromagnets, driven by its potential to enable high-density data storage devices with ultra-low power consumption. However, the underlying mechanism responsible for the magneto-ionic effect on the interlayer exchange coupling remains elusive. In our work, we find that the modulation of the interlayer exchange coupling is highly sensitive to the thickness of the ferromagnetic layer. We have identified that the changes in the interlayer exchange coupling induced by the gate voltage can be associated with the magneto-ionic effects on the top ferromagnetic layer of the synthetic antiferromagnet. The direct contact between the high ion mobility oxide and the top ferromagnetic layer plays a crucial role in facilitating these effects, largely modifying the anisotropy of the layers. Our findings highlight the important role of magneto-ionic control over the properties of the top ferromagnetic layer in governing the observed modifications in the interlayer exchange coupling. This study provides crucial insight into the intricate interplay between stack structure and magneto-ionic effect on magnetic properties in synthetic antiferromagnetic thin film systems.

Interfacial Rivet to Fill Structural Defects: A Spacer Engineering Gift for 3D Solar Cells.

The combination of 2D and 3D perovskites to passivate surfaces or interfaces with a high concentration of defects shows great promise for improving the efficiency of perovskite solar cells (PSCs). Constructing high-quality perovskite film systems by precisely modulating 2D perovskites with good morphologies and growth sites on 3D perovskite films remains a formidable challenge due to the complexity of spacer-engineered surface reactions. In this study, phase-pure 2D (HA)2(MA)n-1PbnI3n+1 perovskites with a controlled number of layers (n) are separated on a large scale and exploited as interface rivets to optimize 3D perovskite films, resulting in tunable film structural defects and grain boundaries. The optimized PSCs system benefits from a reduction in non-radiative recombination, resulting in improved optical performance, higher mobility, and lower trap density. The corresponding device achieves a champion power conversion efficiency (PCE) of more than 25%, especially for voltage (VOC) and fill factor (FF). The quality and uniformity of the perovskite films are further confirmed using large-area devices with an active area of 14 cm2, which exhibits a PCE of more than 21.24%. The high-quality thin-film system based on the 2D perovskites presented herein provides a new perspective for improving the efficiency and stability of PSCs.

Unraveling the effect of 600 keV carbon ion irradiation on the structural and magnetic properties of ZnO thin film

600 keV 12C+ carbon ions have been irradiated upon 800 nm thin ZnO film. The thin ZnO films have been grown by pulsed laser deposition technique upon SiO2/Si substrate. The glancing incidence X-ray diffraction study exhibits the hexagonal wurtzite crystal structure of ZnO, having space group P63mc. Systematic X-ray diffraction analysis of both unirradiated and irradiated samples, reveals that the strain decreases in the sample post irradiation. Room temperature magnetization studies have been performed using SQUID-VSM. As the 600 keV carbon ion fluence is varied, an onset of ferromagnetic ordering in the ZnO thin film is observed. The maximum average magnetic moment induced by each carbon ion is found to be about 6.71 μB. X-ray photoelectron spectroscopy has been utilized to analyze the oxidation state of the C/O/Zn, which also rules out the presence of any transition metal elements in carbon ions irradiated ZnO thin film samples. The chemical and structural analysis of the samples have been examined by Raman spectroscopy. It reveals a red shift in A1 (LO) mode, which confirms the presence of tensile strain in the sample post irradiation. These experimental results, clearly indicate that oxygen vacancies and strain in the film trigger the onset of ferromagnetism in the ZnO thin film system.

Magnetic sputtering preparation of hybrid AlN/SiCN thin films with ultrahigh piezoresistivity

Pressure sensors for high temperatures are extensively applied in a variety of industries processes including aerospace, energy conversion, petrochemicals, automotive and oil wells, real-time pressure detection during equipment operation is a critical concern. Silicon is widely used for piezoresistive sensing with good sensitivity, however, harsh environments with temperatures above 150 °C will lead to plastic deformation as well as current leakage. In this work, AlN/SiCN hybrid thin films systems with ultra-high piezoresistive performance are proposed and enabled by coupling with piezoelectric effect. The gauge factors of the AlN/SiCN sensing elements are from 3260 to 21428 upon different stresses, which are significantly greater than those of other piezoresistive ceramics. The piezoresistive performance of SiCN upon compressive stress is significantly enhanced by incorporation piezoelectric effect of AlN. Moreover, the interfacial strengths of the AlN/SiCN thin films are larger than those of single-layer SiCN, demonstrating that incorporation of AlN layers also improves interfacial strength of SiCN films. This work provides a crucial basis for designing novel piezoresistive sensors.

Porous vanadium dioxide thin film-based Fabry−Perot cavity system for radiative cooling regulating thermochromic windows: experimental and simulation studies

Abstract Radiative cooling in smart windows using VO2 – a dynamic thermal management material, is of potential interest for enhancing energy savings in buildings due to its both solar and emittance tuneability in response to changing temperatures. However, studies related to the effects of VO2 thin film microstructure in a multilayer system on emissivity regulation are currently lacking. The present study addresses the thermochromic and emissivity performance of VO2/ZnSe/ITO/Glass Fabry−Perot (F–P) cavity thin film system, by manipulating the porosity in VO2 thin film. The device is fabricated by commercially feasible physical vapor deposition methods such as sputtering and thermal evaporation, most suitable for mass production. The optimized sample with porous VO2 delivers an enhanced long-wave infrared (LWIR) emissivity contrast of Δɛ LWIR ≥ 0.4 preserving a high visible transparency T lum(avg) of ∼41 % compared to dense VO2. Then finite difference time domain (FDTD) simulation is performed to further understand the effects of varying VO2 porosity and ZnSe thickness on the F–P cavity properties. The reduced low-temperature ɛ LWIR (0.1–0.2) gives this film better energy saving in regions where warming demand is dominant as simulated by EnergyPlus.

Tool-integrated thin-film sensor systems for measurement of cutting forces and temperatures during machining

Effective in-process control mechanisms are vital for the future development of production processes and ask for reliable monitoring of process variables. For this, new tool-integrated sensor systems for measuring cutting forces and temperature for machining of hardened steel are proposed. Thin-film technology is used to apply a thermoresistive temperature sensor in the chip-workpiece contact area for the first time on industrial cutting inserts with chip breaker geometry. Complementary piezoresistive thin-film sensors based on diamond-like carbon (DLC) and manganin layers were developed and deposited on a washer. It was placed beneath the indexable insert to measure the cutting forces. Turning experiments were conducted to study sensor life and accuracy. All sensors showed an adequate lifetime for laboratory purposes. Temperature compensation methods were investigated for force measurement and results compared to forces recorded by a dynamometric platform. While temperature compensation for the DLC-based sensor needs further optimization, results of the manganin-based sensor compared well with the expected cutting forces. The manganin thin-film sensor exhibited rapid responsiveness and great reproducibility, underscoring its prospective utility for real-time monitoring of cutting forces in machining operations.

A Comparison of 90° Bending for Foldable Electronics

In order to assess the longevity of foldable electronics, folding or bending tests on model systems need to be performed. However, not all bending tests are created equal in that different configurations lead to different amounts of mechanical damage and thus different electrical responses. Two 90° bending instruments were compared using two model metallic thin film systems on polyimide to establish if the two seemingly similar bending tests yield the same results. The two film systems, namely 300 nm Mo and 130 nm Al on 50 nm Mo, were magnetron-sputtered on polyimide substrates and tested in the custom-built FLEX-E-TEST and the commercially available YUASA test that is capable of in situ resistance measurements. For statistics, 10–12 samples were tested of each film system on each folding device using the same applied bending strain and number of cycles. Samples were intermittently characterized with confocal laser scanning microscopy and electrical resistance to correlate the amount of mechanical damage (crack density) with the electrical normalized resistance ratio of the damaged area. The results show that even with the same bending radius, a similar but not identical amount of mechanical damage forms for both bending devices. Additionally, the resistance as a function of cycles also differs after 10,000 cycles. A closer examination of the damage, especially in the Al/Mo film system, indicates that the speed of the bending, and if the samples experience spring back, can alter the received mechanical damage. The in situ resistance data of the YUASA test were further examined and a suggestion of standardizing how folding or bending test results are reported is provided.

ZnO-Au Hybrid Metamaterial Thin Films with Tunable Optical Properties

ZnO-Au nanocomposite thin films have been previously reported as hybrid metamaterials with unique optical properties such as plasmonic resonance properties and hyperbolic behaviors. In this study, Au composition in the ZnO-Au nanocomposites has been effectively tuned by target composition variation and thus resulted in microstructure and optical property tuning. Specifically, all the ZnO-Au nanocomposite thin films grown through the pulsed laser deposition (PLD) method show obvious vertically aligned nanocomposite (VAN) structure with the Au nanopillars embedded in the ZnO matrix. Moreover, the average diameter of Au nanopillars increases as Au concentration increases, which also leads to the redshifts in the surface plasmon resonance (SPR) wavelength and changes in the hyperbolic behaviors of the films. As a whole, this work discusses how strain-driven tuning of optical properties and microstructure resulted through a novel Au concentration variation approach which has not been previously attempted in the ZnO-Au thin film system. These highly ordered films present great promise in the areas of sensing, waveguides, and nanophotonics to name a few.

Periodicity staircase in a centrosymmetric Fe/Gd magnetic thin film system

The presence of multiple competing periodicities may result in a system to go through states with modulated periodicities, an example of which is the self-similar staircase-like structure called the Devil’s Staircase. Herein we report on a novel staircase structure of domain periodicity in an amorphous and centrosymmetric Fe/Gd magnetic thin film system wherein the reciprocal space wavevector Q due to the ordered stripe domains does not evolve continuously, rather exhibits a staircase structure. Resonant X-ray scattering experiments show jumps in the periodicity of the stripe domains as a function of an external magnetic field. When resolved in components, the length-scale step change along Qx was found to be an integral multiple of a minimum step height of 7 nm, which resembles closely to the exchange length of the system. Modeling the magnetic texture in the Fe/Gd system as an achiral spin arrangement, we have been able to reproduce the steps in the magnetization using a Landau-Lifshitz spin dynamics calculation. Our results indicate that anisotropy and not the dipolar interaction is the dominant cause for the staircase pattern, thereby revealing the effect of achiral magnetism.

In situ characterization of stresses, deformation and fracture of thin films using transmission X-ray nanodiffraction microscopy.

The use of hard X-ray transmission nano- and microdiffraction to perform in situ stress and strain measurements during deformation has recently been demonstrated and used to investigate many thin film systems. Here a newly commissioned sample environment based on a commercially available nanoindenter is presented, which is available at the NanoMAX beamline at the MAX IV synchrotron. Using X-ray nanoprobes of around 60-70 nm at 14-16 keV and a scanning step size of 100 nm, we map the strains, stresses, plastic deformation and fracture during nanoindentation of industrial coatings with thicknesses in the range of several micrometres, relatively strong texture and large grains. The successful measurements of such challenging samples illustrate broad applicability. The sample environment is openly accessible for NanoMAX beamline users through the MAX IV sample environment pool, and its capability can be further extended for specific purposes through additional available modules.

Моделирование процессов формирования и исследование свойств нанопленок Co-Fe-Nb

The article presents the study of the formation and the analysis of the structure and properties of nanomaterials, which are cobalt-iron-niobium thin-film systems. A mathematical model is presented that allows to describe the combined behavior of atomic spins and coordinates. The generalized version of the model can use any type of the force interaction potential and take into account various contributions to the magnetic Hamiltonian depending on the specific problem being solved. When conducting computational experiments, the force potential of the modified embedded atom method (MEAM) was considered; to take into account magnetic interactions, a simplified magnetic Hamiltonian that includes the exchange interaction and the Zeeman interaction was used. The implementation of the mathematical model is presented in the LAMMPS software package, which was used to carry out numerical calculations. During the computational experiments, two separate problems were considered. In the first problem, the processes of deposition, interaction and ordering of a multilayer atomistic cobalt-iron-niobium system were analyzed. It has been shown that when niobium atoms are deposited onto a substrate, a relief nanofilm with irregularities up to a nanometer in height is formed. The contact between iron and niobium nanofilms is more blurred compared to the similar area of the contact between cobalt and iron nanofilms. In the second problem, the self-organization and reorientation of atomic spins in an iron nanofilm with a crystalline structure were analyzed. Calculations were carried out with and without an existing external magnetic field. The appearance of skyrmions (vortex flows) during the spin interaction of iron atoms was recorded. The simulation has shown that under the influence of an external magnetic field, an induced magnetic moment appears in the iron nanofilm, opposite to the induction vector of the external field.

Effect of low-temperature oxidation and heat treatment under vacuum on the Al-Be interdiffusion process.

The oxidation of the Be/Al and Al/Be bilayer thin film systems deposited by magnetron sputtering have been studied by photoelectron spectroscopy and transmission electron microscopy. Both systems are oxidized according to the Cabrera-Mott model in the air. A Be/BeO/Al/Al2O3 structure is formed, with aluminium represented as localized nanocrystals. The thickness of the beryllium in the Al/Be system and the formed beryllium oxide is not enough to prevent the diffusion of aluminium ions under the influence of the Mott potential, and as a result, the surface layer is a mixture of beryllium and aluminium oxides. The effect of oxidation processes on the intermixing of non-interacting metals in a bilayer nanostructure has been shown for the first time. Annealing of the Be/Al bilayer leads to beryllium diffusion to the surface and the reduction of aluminium oxide, which leads to the destruction of the bilayer structure. In the Al/Be system in the range up to 200 °C, additional beryllium oxide is formed with increasing temperature, and the rest of the metallic beryllium diffuses into the aluminium layer. Based on studies, we conclude that multilayer Al/Be nanostructures have potentially low thermal stability, which requires the use of barrier layer techniques to limit interdiffusion.

Statistically distributed nano-scratch testing of AlFeMnNb, AlFeMnNi, and TiN/Si3N4 thin films on silicon

For studying the damage tolerance of thin films, a novel randomly distributed nano-scratch test method was introduced and demonstrated as a promising characterization method. It is capable of more closely simulating the damage progression in abrasion, where material removal can be influenced by the interaction between damage produced by previous scratches in close proximity. In addition to studying how localized failure events affect subsequent damage progression, it is possible to monitor the evolution of the film degradation cycle-by-cycle using the mean depth and friction over the scratch. Randomly distributed nano-scratch tests were performed on the high entropy alloy AlFeMnNb, AlFeMnNi, and nanocomposite (nc-) TiN/Si3N4 thin films on silicon. Brittle fracture and film removal with extensive chipping of the Si substrate were observed over the entire scratched region on AlFeMnNi and nc-TiN/Si3N4 in distributed scratch tests at applied loads that were only ∼0.2–0.3 of the load needed to produce the chipping in ramped load nano-scratch tests due to film and substrate fatigue. In contrast, the softer AlFeMnNb deformed predominantly by ductile ploughing with significantly improved damage tolerance and crack resistance in the distributed scratch tests. The new method can be used to evaluate the performance of thin films in applications where they can be exposed to abrasive/sliding wear. It can provide a more direct measure of abrasion resistance than assuming high resistance to abrasive wear from coating hardness. In the thin film systems studied, higher hardness was associated with greater fracture and delamination in the distributed scratch tests.

Multilayer ferromagnetic spintronic devices for neuromorphic computing applications.

Based on ferromagnetic thin film systems, spintronic devices show substantial prospects for energy-efficient memory, logic, and unconventional computing paradigms. This paper presents a multilayer ferromagnetic spintronic device's experimental and micromagnetic simulation-based realization for neuromorphic computing applications. The device exhibits a temperature-dependent magnetic field and current-controlled multilevel resistance state switching. To study the scalability of the multilayer spintronic devices for neuromorphic applications, we further simulated the scaled version of the multilayer system read using the magnetic tunnel junction (MTJ) configuration down to 64 nm width. We show the device applications in hardware neural networks using the multiple resistance states as the synaptic weights. A varying pulse amplitude scheme is also proposed to improve the device's weight linearity. The simulated device shows an energy dissipation of 1.23 fJ for a complete potentiation/depression. The neural network based on these devices was trained and tested on the MNIST dataset using a supervised learning algorithm. When integrated as a weight into a 3-layer, fully connected neural network, these devices achieve recognition accuracy above 90% on the MNIST dataset. Thus, the proposed device demonstrates significant potential for neuromorphic computing applications.

Magnetization dynamics and spin-glass-like origins of exchange-bias in Fe–B–Nb thin films

The phenomenon of exchange bias has been extensively studied within crystalline materials, encompassing a broad spectrum from nanoparticles to thin-film systems. Nonetheless, exchange bias in amorphous alloys has remained a relatively unexplored domain, primarily owing to their inherently uniform disordered atomic structure and lacking grain boundaries. In this study, we present a unique instance of exchange bias observed in Fe–B–Nb amorphous thin films, offering insights into its origins intertwined with the system's spin-glass-like behavior at lower temperatures. The quantification of exchange bias was accomplished through a meticulous analysis of magnetic reversal behaviors in the liquid-helium temperature range, employing a zero-field cooling approach from various initial remanent magnetization states (±MR). At reduced temperatures, the appearance of asymmetric hysteresis, a hallmark of negative exchange bias, undergoes a transformation into symmetric hysteresis loops at elevated temperatures, underscoring the intimate connection between exchange-bias and dynamic magnetic states. Further investigations into the magnetic thermal evolution under varying probe fields reveal the system's transition into a spin-glass-like state at low temperatures. We attribute the origin of this unconventional exchange bias to the intricate exchange interactions within the spin-glass-like regions that manifest at the interfaces among highly disordered Fe-nuclei. The formation of Fe-nuclei agglomerates at the sub-nanometer scale is attributed to the alloy's limited glass-forming ability and the nature of the thin-film fabrication process. We propose that this distinctive form of exchange bias represents a novel characteristic of amorphous thin films.

Accelerating the Development of New Silicon-Based Anode Materials

In this work we have demonstrated the feasibility of using thin film systems as a steppingstone to accelerate the development of commercially relevant silicon-based anode materials for Li-ion batteries. Understanding new materials in conventional particle-based electrode systems is often complex. Lithium and electrolyte interact not only with the active material particles, but also with the different supporting components of the electrode, leaving it difficult to directly assess the electrochemical contribution of the active material. This is further complicated by the electrochemical behavior of such electrodes also being strongly dependent on processing conditions, like casting and drying procedures. Additionally, it is often also a challenge to synthesize such materials in particle form with the required chemical composition and monodispersity in the first place. Therefore, it would be highly beneficial to study and screen new anode materials without having to assume and assess these different factors. That is of particular importance during the optimization stage of the chemical composition for the active material, for which a significant number of samples is typically needed. Thus, evaluating the material in a thin film system is a simple and reproducible method of determining a material’s potential as a future anode material.Such thin films of active materials can reliably be made with a large range of thicknesses, compositions, element combinations and coatings, using multiple flexible and reproducible thin film deposition techniques available. In the present work, we have investigated silicon-based materials made by PECVD and sputtering: pure silicon and sub-stoichiometric versions of silicon nitride, silicon carbide, and silicon phosphide (SiNx, SiCx, SiPx). For evaluation of the applicability of the thin film model system, in several cases we have also compared the results to particles of the same material with similar chemical composition synthesized via a free space CVD process [1].Preliminary evaluation shows good agreement between results for thin film systems compared to what is known for particles of the same material. SiNx particles show good agreement with thin film results where a high nitrogen content decreases the capacity, while increasing the stability due to the formation of a stabilizing matrix around the active silicon [2]. Differences in the differential capacity analysis of similar materials in particle and thin film forms demonstrates the greater complexity in interpreting the data from the more intricate particle-based systems. SiCx is known to react in a similar fashion as SiNx where its coulombic efficiency and capacity decreases with increasing carbon-content, while its stability has been seen to increase due to a similar stabilizing matrix [3]. Reference s : [1] H. F. Andersen et al., ECS Trans., vol. 62, no. 1, pp. 97–105, 2014.[2] A. Ulvestad et al., ACS Nano, vol. 15, no. 10, pp. 16777–16787, 2021.[3] X. D. Huang et al., RSC Adv., vol. 8, no. 10, pp. 5189–5196, 2018.

(Invited) Controlling Metal Exsolution on Oxides By External Drivers – Role of Elastic Strain and Ion Irradiation

Exsolution is an effective approach to fabricating oxide-supported metal nanoparticle catalysts via phase precipitation out of a host oxide. A fundamental understanding and control of the exsolution kinetics are needed to engineer exsolved nanoparticles to obtain higher catalytic activity toward clean energy and fuel conversion. Since oxygen release via oxygen vacancy formation in the host oxide is behind oxide reduction and metal exsolution, we hypothesize that the kinetics of metal exsolution should depend on the kinetics of oxygen release. In this work, we probe the surface exsolution kinetics both experimentally and theoretically using thin-film perovskite oxide model systems, show its relation to the oxygen evolution kinetics. We also tune defect formation and the resulting metal exsolution, by external drivers including elastic strain and ion irradiation. Using both of these external drivers, we couple to the formation of point defects and defect clusters, that serve as nucleation sites for nanoparticle exsolution. As a result, we can controllably tune size, density, composition and position of the exsolved metal nanoparticles.

Вплив аргонвмісного середовища відпалу на перебіг структурно-фазових перетворень в тонкоплівкових композиціях Ni/Ti

This study is focused on the effect of isothermal annealing in an argon atmosphere (200 Pa) in the temperature range of 200–600 °C on the evolution of diffusion-induced structural phase transformations in Ni/Ti layered thin films with different modulation period but similar total thickness of 60 nm. Changes in the structure and phase composition of nanoscale films have been examined using X-ray diffraction technique, and the chemical composition has been analyzed using secondary ion mass spectrometry. Annealing at 300 °C induces the development of diffusion interaction between the Ni and Ti layers, leading to the formation of intermetallic NixTiy phases of various stoichiometry at higher annealing temperatures. It is shown that an increased number of layers promotes a significant activation of diffusion processes between the components of the system, resulting in a change in its phase composition at lower annealing temperatures. Meanwhile, for all investigated samples, annealing at elevated temperatures (>500 °C) causes the agglomeration of Ti on the free surface with the probable formation of a protective oxide layer. It was established that the decisive influence on thermally induced phase formation is exerted by two competing factors: the use of an argon-containing annealing atmosphere contributes to the intensification of mass transfer processes between the materials of metal nanolayers compared to similar heat treatment in a vacuum, while the decrease of the modulation period of the thin-film system promotes the amorphization processes at the interface between metal layers with a corresponding inhibition of structural ordering processes. Keywords: nanoscale films, NiTi, diffusion, argon, isothermal annealing.