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The development of deposition processes for metal carbide thin films is rapidly advancing, driven by their potential for applications including catalysis, batteries, and semiconductor devices. Within this landscape, atomic layer deposition (ALD) offers exceptional conformality, uniformity, and thickness control on spatially complex structures. This paper presents a comprehensive study on the thermal ALD of MoCx with MoCl5 and 1,4‐bis(trimethylgermyl)‐1,4‐dihydropyrazine [(Me3Ge)2DHP] as precursors, focusing on the functional properties and characterization of the films. The depositions are conducted at 200–300 °C and very smooth films with RMS Rq ≈0.3–0.6 nm on Si, TiN, and HfO2 substrates are obtained. The process has a high growth rate of 1.5 Å cycle−1 and the films appear to be continuous already after 5 cycles. The films are conductive even at thicknesses below 5 nm, and films above 18 nm exhibit superconductivity up to 4.4 K. In lieu of suitable references, Raman modes for molybdenum carbides and nitrides are calculated and X‐ray diffraction and X‐ray photoelectron spectroscopy are used for phase analysis. [ABSTRACT FROM AUTHOR]

This study aimed to evaluate the surface characteristics of a nanocrystalline hydroxyapatite coating made through atomic layer deposition (ALD-HA) on titanium surfaces and to investigate its effect on blood coagulation and platelet adhesion. Grade 2 square titanium discs (0.7 cm, 1 mm thick) were used (n = 108). Half of the substrates (n = 54) were coated with ALD-HA, and the other half were used as the non-coated control. Surface free energy (SFE), contact angle (CA), surface roughness (Ra), and chemical composition were evaluated. Blood thrombogenic properties were assessed on ALD-HA and non-coated surfaces using the kinetic clotting time method. The platelets' adhesion and morphology were also evaluated. The ALD-HA-coated surfaces demonstrated significantly higher polar SFE (p < 0.001) and lower CA (p < 0.001) values compared to the non-coated surfaces. In addition, the surface roughness was significantly lower for the ALD-HA (p < 0.001) than for the non-coated surfaces. Platelets adhered to both surfaces; however, there was variability in platelet morphologies in different areas with higher platelet density on the ALD-HA surfaces. There was no significant difference in the overall absorbance values of the hemolyzed hemoglobin for both substrates, and the total clotting time was achieved at 60 min. It can be concluded that the ALD-HA coating of titanium can enhance surface wettability, increase surface free energy, and support blood coagulation and platelet adhesion. [ABSTRACT FROM AUTHOR]

The present study describes atomic layer deposition (ALD) processes and characterization of CoF2, NiF2, and HoF3 thin films. For CoF2 deposition CoCl2(TMEDA) (TMEDA = N,N,N′,N′-tetramethylethylenediamine) and NH4F were used as precursors. CoF2 deposition was studied at 180–275 °C, resulting in a growth per cycle (GPC) of 0.7 to 1.2 Å. All the films consist of tetragonal CoF2 according to XRD. The impurity contents were measured with ToF-ERDA and less than 1 at% of N and Cl were detected in the films, indicating effective reactions. In addition, the F/Co ratio is close to 2 as measured by the same method. The saturation of the GPC with respect to precursor pulses and purges was verified at 250 °C. The common feature of ALD metal fluoride films – remarkable roughness – is encountered also in this process. However, the films became smoother as the deposition temperature was increased. CoF2 deposition was also demonstrated on graphite substrates. NiF2 deposition was studied at 210–250 °C by using Ni(thd)2 and TaF5 or a new fluoride source NbF5 as the precursors. Tetragonal NiF2 was obtained, but the oxygen and hydrogen contents in the films were remarkable, up to ∼11 at%, as measured by ToF-ERDA. This was observed also when the films were in situ capped with YF3. NbF5 was shown to be a potential fluoride precursor by combining it with Ho(thd)3 to deposit HoF3 films. Orthorhombic HoF3 was obtained at deposition temperatures of 200–275 °C. The films deposited at 235–275 °C are pure, and the Nb contents in films deposited at 250 and 275 °C are only 0.21 and 0.15 at%. The main impurity in both films is oxygen, but the contents are only 1.5 and 1.6 at%. The saturation of the GPC with respect to precursor pulses was verified at 250 °C. The GPC is ∼1 Å. [ABSTRACT FROM AUTHOR]

Atomic layer deposition processes with inherent substrate selectivity are more straightforward for area-selective atomic layer deposition (AS-ALD) than approaches using surface passivation or activation with self-assembled monolayers (SAMs), small molecule inhibitors (SMIs) or seed layers. Here, ALD of ZnS using elemental zinc and sulfur as precursors is reported to have excellent inherent selectivity. At 400–500 °C for 250 cycles, substantial ZnS growth was observed on Ti and TiO2 surfaces while no growth was measured on native SiO2 and Al2O3 surfaces. On TiO2, the ZnS growth rate remains constant at 1.0 Å per cycle at temperatures of 400–500 °C. On Ti, in contrast, the initial growth rate increases significantly from 1.2 Å per cycle at 350 °C to 6.2 Å per cycle at 500 °C. The high growth rates on Ti are believed to be caused by CVD-like growth during the early ALD cycles, arising from the reservoir effect of the Ti layer for Zn atoms. After the first 100 cycles, the growth rate decreases from 3.5 to 1.0 Å per cycle, the same as the growth rate on TiO2. Selective adsorption of sulfur on TiO2 over Al2O3 and SiO2 is assumed to be the selectivity mechanism on TiO2. Self-aligned deposition of ZnS was successfully demonstrated on a micrometer-scale Ti/native SiO2 pattern and on a nanometer-scale TiO2/Al2O3 pattern at 450 °C for 250 cycles; ZnS films with a thickness of ∼80 nm were selectively deposited on Ti over native SiO2, and ZnS films with a thickness of ∼23 nm were selectively deposited on TiO2 over Al2O3. [ABSTRACT FROM AUTHOR]

This paper presents preparation of boron‐doped Al2O3 thin films by atomic layer deposition (ALD) using phenylboronic acid (PBA) and trimethylaluminum (TMA) as precursors. Deposition temperatures of 160–300 °C are studied, giving a maximum growth per cycle (GPC) of 0.77 Å at 200 °C. Field emission scanning electron microscopy (FESEM) and atomic force microscopy (AFM) are used to study the surface morphology and roughness of the films. Attenuated total reflectance Fourier transform infrared spectroscopy (ATR‐FTIR), Time‐of‐flight elastic recoil detection analysis (ToF‐ERDA), and X‐ray photoelectron spectroscopy (XPS) are used to study the composition of the films. An annealing process is carried out at 450 °C for 1 h to investigate its effect on the elemental composition and electrical properties of the boron‐doped Al2O3 thin films. The boron‐doped Al2O3 70 nm thick film deposited at 200 °C has a boron content of 3.7 at.% with low leakage current density (10−9 to 10−6 A cm−2) when the film thickness is 70 nm. The dielectric constant of this boron doped Al2O3 film is 5.18. [ABSTRACT FROM AUTHOR]