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Corrigendum to “Wetting state and mechanical property alteration for the Fe3Si films using rapid thermal annealing under various temperatures” [Heliyon Volume 9, Issue 12, December 2023, Article e22511](S2405844023097190)(10.1016/j.heliyon.2023.e22511)
(2025-05-01)
Borwornpornmetee, Nattakorn
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Traiprom, Thawichai
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Kusaba, Takafumi
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Sittimart, Phongsaphak
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Naragino, Hiroshi
In the original published version of this article, reference [22] was added in error: P. Du et al. tuned the mechanical properties of SiOC films with RTA under nitrogen ambient at different temperatures of 400, 600, and 800 °C for 10 min [21]. The treated SiOC films showed a change in residual stress, turning from compressive to tensile after RTA, and an improvement in hardness and Young's modulus as the temperatures were raised [22]. [22] Z. Bazhan, F.E. Ghodsi, J. Mazloom, Effect of phase transition induced by annealing temperature on wettability, optical and photocatalytic properties of nanostructured iron oxide thin film, J. Mater. Sci. Mater. Electron. 29 (2018) 11489–11497, https://doi.org/10.1007/s10854-018-9244-4. The reference and citation have been removed and the references have been renumbered accordingly. The intext citations have been updated to reflect this change. The correct version can be found below: P. Du et al. tuned the mechanical properties of SiOC films with RTA under nitrogen ambient at different temperatures of 400, 600, and 800 °C for 10 min [21]. The treated SiOC films showed a change in residual stress, turning from compressive to tensile after RTA, and an improvement in hardness and Young's modulus as the temperatures were raised. The authors apologize for the errors. Both the HTML and PDF versions of the article have been updated to correct the errors.
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Investigation into the impedance, dielectric behavior, and conductivity within p-silicon/n-nanocrystalline iron disilicide heterojunctions and equivalent circuit model in relation to temperature
(2025-03-15)
Borwornpornmetee, Nattakorn
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Sittimart, Phongsaphak
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Traiprom, Thawichai
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Paosawatyanyong, Boonchoat
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Yoshitake, Tsuyoshi
The p-Si/n-nanocrystalline FeSi<inf>2</inf> heterojunctions constructed through facing-targets sputtering were characterized for impedance under various frequencies and temperatures of between 160−400 K. Imaginary and real impedance plots for all temperatures demonstrated single semicircular arc with negative temperature dependency. From the arc, a circuit model equivalent to electrode resistance serially connected to several loops, each consisting of a parallel circuit comprising a resistance//constant phase element (Q), corresponding to the crystallite, crystallite boundary, and interface. All resistances increased with decreasing temperatures, while the Q values decreased but behaved as ideal capacitors for all temperatures. The dielectric constants versus increasing temperature demonstrated a linear increase. At 300 K and 1 MHz, the dielectric constant was 24.5 with 0.1 loss tangent, denoting its possible usage for filtration and storage. The alternating-current conductivities disclosed that direct-current conductivities increased as the temperature increased. The exponents from Jonscher's fit were 1 or less around 180 K and the values beyond 1 at higher temperatures, indicating the shift from long transitional transport to localized hopping transport. The activation energy based on conductivities was higher than the one based on relaxation times, implying that excess charge led to more energy requirements for transportation.
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Modification of wetting and mechanical traits via rapid annealing under varying temperatures for β-FeSi2
(2025-02-01)
Borwornpornmetee, Nattakorn
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Traiprom, Thawichai
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Kusaba, Takafumi
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Sittimart, Phongsaphak
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Naragino, Hiroshi
The examination on β-FeSi<inf>2</inf> thin films prepared via facing-target sputtering onto Si(111), subjected to rapid thermal annealing under varying temperatures of 200–800 °C, revealed numerous changes in the film’s physical traits. The energy-dispersive X-ray spectroscope findings corroborate the anticipated atomic composition, displaying strong Si and small Fe peaks, including C and Al impurities. The Fe/Si proportions barely changed after rapid annealing. Under 200 °C and 400 °C, the X-ray diffractometer spectra indicated that orientation (202/220) and (404/440) of β-FeSi<inf>2</inf> were improved by rapid annealing, while surface morphology also revealed gradual enhancement in grain structure and roughness. Temperatures of over 600 °C induced recrystallization of the films, resulting in the reduced orientation peak’s intensities, grain compression, and coarsening. These changes caused the air gap to collapse, turning the film’s surface hydrophilic with contact angles of 86.15° at 600 °C and 63.00° at 800 °C. In contrast, the films retained hydrophobicity with contact angles of 93.40° at 200 °C and 91.20° at 400 °C compared to the as-prepared films of 96.75°. The hardness and Young’s modulus improved with rising temperature to 15.2 GPa and 225.8 GPa at maximum. This has ramifications for their prospective use in self-cleaning and hard-coating applications.
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Temperature dependency of impedance, dielectric, and conductivity properties for Si-p/beta-FeSi2-n heterostructures created through facing target sputtering
(2024-08-15)
Borwornpornmetee, Nattakorn
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Sittimart, Phongsaphak
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Traiprom, Thawichai
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Paosawatyanyong, Boonchoat
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Yoshitake, Tsuyoshi
To connect thermal dependency with Si-p/beta-FeSi<inf>2</inf>-n heterostructure efficiency, this work explored the impedance characteristics accompanied by dielectric and conductivity properties under different temperatures of 160–400 K. The Nyquist impedance plots for the heterostructures showed a semicircular arc that shrank as the temperature increased. These can be equivalently interpreted as a loop of single resistance paralleled to single constant phase element representing the heterostucture which also paralleled to inductive elements representing the inductive effect, serially connected to electrode resistance. The dielectric properties implied a shift in behavior for the relaxation process since donor-acceptor deionization occurred when the temperatures reached 320 K or higher due to shorter relaxation time and higher thermal dissipation. The conductivity properties indicate that the transport mechanism at 180 K or lower involves a prolonged transitional movement before transitioning into localized hopping at higher temperatures, corresponding to faster carrier movement. The relaxation and activation energy of the heterostructure reveal drastic transition of the energy from a low temperature of 160–240 K to a higher temperature of 320–400 K, where the electrical mechanism of the heterostructures become highly dependent on the temperature likely due to the high carrier density based on unevenly high activation energy.
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Physical feature exploration of nanocrystalline FeSi2 surface with argon plasma etching under varying power
(2023-12-01)
Borwornpornmetee, Nattakorn
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Sittimart, Phongsaphak
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Phatthanakun, Rungrueang
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Nakajima, Hideki
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Paosawatyanyong, Boonchoat
Nanocrystalline (NC) FeSi<inf>2</inf> films were created on Si(111) wafers via direct-current sputtering with facing targets at an ambient temperature, then the films were etched by Ar plasma generated through microwave source at different powers of 50, 100, and 150 W. The surface morphology of the as-coated NC FeSi<inf>2</inf> films showed numerous small uniform crystallites and root-mean-square roughness of 4.65 Å. The surface for each etched NC FeSi<inf>2</inf> film showed appearance of holes and slight increase in the roughness as the power increased. X-ray photoelectron spectra showed that the etching decreased the content of hydrophobic carbon and increased the presence of polar oxide group on the NC FeSi<inf>2</inf> films as the power increased. These changes should be the factor behind the shift from hydrophobic state to hydrophilic state. The contact angle of the unetched NC FeSi<inf>2</inf> film surface was 100.55°, which is hydrophobic. The NC FeSi<inf>2</inf> film's surface reached a minimum contact angle of 35.65°, which belong to hydrophilic state, when the etching power was increased to 150 W. The mechanical properties of NC FeSi<inf>2</inf> films rarely affect by Ar plasma. The change in surface state to nearly superhydrophilic after plasma etching indicate possibility to develop NC FeSi<inf>2</inf> into a self-cleaning surface coating material.
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Wetting state and mechanical property alteration for the Fe3Si films using rapid thermal annealing under various temperatures
(2023-12-01)
Borwornpornmetee, Nattakorn
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Traiprom, Thawichai
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Kusaba, Takafumi
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Sittimart, Phongsaphak
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Naragino, Hiroshi
The current research demonstrates the modification of the wetting behavior and mechanical features as well as structure and morphology of Fe<inf>3</inf>Si films created via facing target sputtering by the rapid thermal annealing (RTA) with the set RTA temperatures (T<inf>RTA</inf>) of 200, 400, 600, and 800 °C. Following the RTA process, the crystallinity of Fe<inf>3</inf>Si developed under 400 °C or below. At the 600 °C and 800 °C T<inf>RTA</inf>, new crystal orientations emerged for FeSi and then β-FeSi<inf>2</inf>, respectively. Together with composition results, the Fe<inf>3</inf>Si films were proven to change into FeSi and then FeSi<inf>2</inf> under a high T<inf>RTA</inf> regime. At temperatures of 600 °C and 800 °C, large crystallites, including the scraggly interface, were observed. The root-mean-square roughness roughened slightly according to the RTA process at T<inf>RTA</inf> of 600 °C or above. The hydrophobic properties of the Fe<inf>3</inf>Si film surfaces became hydrophilic after the RTA procedure at a T<inf>RTA</inf> value above 400 °C. The hardness value of the Fe<inf>3</inf>Si films evidently increased through RTA at 600 °C and 800 °C. Thus, above 400 °C, the RTA process significantly alters the physical features of as-created Fe<inf>3</inf>Si films.
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Impedance characteristics under different voltages of n-β-FeSi2/p-Si heterojunctions constructed via facing target sputtering
(2023-10-01)
Borwornpornmetee, Nattakorn
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Chaleawpong, Rawiwan
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Charoenyuenyao, Peerasil
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Nopparuchikun, Adison
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Paosawatyanyong, Boonchoat
Utilizing a substrate temperature of 600 °C, n-semiconducting iron disilicide (β-FeSi<inf>2</inf>)/p-silicon heterojunctions have been constructed with direct-current sputtering and a couple of facing FeSi<inf>2</inf> targets. The impedance examination was carried out under a voltage ranging from −1 V to 1 V. Each complex impedance arch unveiled only one arc with its center beneath the real axis. Elevated voltage facilitates a reduction in the semicircle size. Based on the simulated equivalent circuit model, the heterojunctions possessed high parallel resistance and a constant phase element (CPE) at the grain boundary, raising the V. The CPE for the grain, grain boundary, and junction implied behavior close to the ideal capacitor. The dielectric loss tangent results indicated that the heterojunctions exhibited leakage behavior. From the alternating-current conductivity plots, the plateau and dispersion areas were revealed at low and high frequencies, respectively. The direct-current conductivity was 9.49 × 10−3 S cm−1 at −1 V and elevated to 8.87 × 10−2 S cm−1 at 1 V, due to the augmented charge carriers. Jonscher's power law fitting exposed that the constructed heterojunction exhibited short-range hopping within the boundary of the neighborhood.
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Determining the Annealing Temperature Dependency of Wetting and Mechanical Features on Fe3Si Films
(2023-08-01)
Borwornpornmetee, Nattakorn
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Achirawongwat, Chawapon
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Traiprom, Thawichai
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Saekow, Bunpot
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Porntheeraphat, Supanit
The impact of thermal annealing under temperature alteration on the wetting and mechanical attributes of Fe<inf>3</inf>Si films built through facing target sputtering (FTS) is an essential topic for study in order to identify their characteristics under varying temperatures. Consequently, we introduced a thermal annealing process in a vacuum for two hours under varying temperatures of 300, 600, and 900 °C to our Fe<inf>3</inf>Si films created via FTS. The primary purpose of this current research is to examine the effect of the thermal annealing technique under temperature alteration on the wetting and mechanical traits of Fe<inf>3</inf>Si films. In this research, Fe<inf>3</inf>Si films were built onto the Si wafer by FTS and divided for use in thermal annealing under temperature alteration. The structural, morphological, wetting, and mechanical traits of the Fe<inf>3</inf>Si films under thermal annealing are provided in the present work. Based on our information, this work represents an original study on the change in wetting and mechanical traits of Fe<inf>3</inf>Si films through thermal annealing under temperature alteration.
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Investigation of morphological surface features, wetting behavior and mechanical traits under various substrate temperatures for beta iron disilicide prepared via facing-targets sputtering
(2022-08-01)
Charoenyuenyao, Peerasil
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Chaleawpong, Rawiwan
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Borwornpornmetee, Nattakorn
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Paosawatyanyong, Boonchoat
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Sittimart, Phongsaphak
Using facing-targets sputtering, semiconducting iron disilicide (β-FeSi<inf>2</inf>) film layers were sputtered and coated on Si wafers owning (111) orientation. Under experimental conditions, the heating temperatures of the substrate (T<inf>substrate</inf>) were varied at 525 °C, 550 °C, 600 °C and 660 °C. The acquired XRD patterns indicated a strong β(202/220) peak of around 29.1° for the β-FeSi<inf>2</inf> films prepared at a T<inf>substrate</inf> of at least 600 °C. The β-FeSi<inf>2</inf> film surface prepared at a T<inf>substrate</inf> of 525 °C comprised several crystallites, which were arranged to form a grain format at a higher T<inf>substrate</inf>. The root mean square roughness for the film surface prepared at a T<inf>substrate</inf> of 525 °C was 0.49 nm, where it increased to 0.98 nm, 2.39 nm, and 4.23 nm at T<inf>substrate</inf> of 550 °C, 600 °C, and 660 °C, respectively. The films prepared at a T<inf>substrate</inf> of 525 °C exhibited an average contact angle (θ<inf>CA</inf>) of 91.15°, and improved to 103.80° after employing a T<inf>substrate</inf> of 660 °C. These results hinted at the possibility of employing the β-FeSi<inf>2</inf> films prepared at all T<inf>substrate</inf> in the hydrophobic surface application. The estimated hardness and elastic modulus of the β-FeSi<inf>2</inf> films prepared at T<inf>substrate</inf> of 525 °C were 12.78 GPa and 190.98 GPa, respectively, which increased to 21.27 GPa and 248.67 GPa, respectively, for the films prepared at 660 °C. According to mechanical results, the β-FeSi<inf>2</inf> films prepared at 660 °C exhibited the potential to be developed for use in hard coating application.
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Reverse bias dependent impedance and dielectric properties of Al/n-NC FeSi2/p-Si/Pd heterostructures formed by facing-targets sputtering
(2022-08-01)
Borwornpornmetee, Nattakorn
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Chaleawpong, Rawiwan
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Charoenyuenyao, Peerasil
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Nopparuchikun, Adison
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Paosawatyanyong, Boonchoat
Al/n-NC FeSi<inf>2</inf>/p-Si/Pd heterostructures were formed by facing-targets sputtering. From the dark J-V results, the device showed rectifying action with leakage current. In this work, impedance spectroscopy was employed to study the electrochemical characteristics of the heterostructures, which were inspected within a frequency (f) range from 20 Hz to 2 MHz. The range of the biased voltage (V) was −1 V to 0 V. All plots of real and imaginary impedances possessed single semi-circular arcs for all bias V values. The relaxation time was 2.00 μs at −1 V, and it became faster at 0 V with 0.42 μs. The equivalent circuit for the heterostructures consisted of series resistance (R<inf>s</inf>) combined with three sets of shunt circuits of resistance (R<inf>p</inf>) and a constant phase element (CPE), representing grain, grain boundary, and junction, respectively. The simulated R<inf>s</inf> and R<inf>p</inf> values decreased, while all CPE values increased as the biased V increased. For the dielectric properties, the real permittivity (ε′) values of 86.70 at 0 V and 20.22 at −1 V were disclosed at 100 Hz; all ε′ values decreased as the f value was increased. The loss tangent revealed to be very high due to dielectric loss being much higher than ε′ values, indicating the device to be leaky. The alternating conductivities plotted against f started at a low level in low f zones and grew exponentially when f reached higher values for all V values. Direct current conductivity was observed at 1.66 × 10−4 S m−1 at 0 V, which reduced to 2.67 × 10−5 S m−1 at −1 V. The dimensionless exponent of the conductivity results was higher than 1, indicating the hopping movement within the local site.

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