[Audio] The slides presented above are my educational background, research publications, instrument training, academics, and internship experiences. In the second year of my Ph.D. program, I have published two research papers and completed training on various instruments such as pulsed laser deposition, electron beam evaporator, and scanning probe microscope. I also taught physics to undergraduate students and participated in evaluating their bachelor's thesis presentations. In the third year, I plan to participate in a research internship and continue my research on bismuth ferrite. I will also receive training on piezo response force microscopy and cryogenic-free electrical transport option measurement. My research focuses on characterizing the structural properties of bismuth ferrite using x-ray diffraction and other techniques. I have found that the material exhibits a crystalline structure, which is consistent with previous studies. I am excited about the opportunities ahead and look forward to contributing to the field of materials science.. 

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Student Name: Saleh H. Fawaeer Academic Year: 2nd

Doctoral Thesis Title: Properties of Bismuth Ferrite Heterostructures

Supervisor: Doc. Ing. Vlasta Sedláková, Ph.D.
Co-Supervisor: Doc. Mgr. Dinara Sobola, Ph.D.

[Audio] Fabrication of Ti and TiO2 buffer layers on various substrates will enable the growth of high-quality Bismuth Ferrite (B-F-O--) films. This planned activity includes the fabrication of Yttrium ferrite (YFeO3, Y-F-O--) buffer layers on Ti/Si and TiO2/Si substrates, as well as on Al2O3 and MgO substrates. The subsequent characterization of these films using 10-ray photoelectron spectroscopy (X-P-S--), 10-ray diffraction (X-R-D--), Raman spectroscopy, vacuum-vacuum atomic spectroscopy (V-VASE), scanning electron microscopy (S-E-M--), atomic force microscopy (A-F-M--), magnetic force microscopy (M-F-M--), and vibrating sample magnetometry (V-S-M--) will provide valuable insights into their structural, chemical, optical, and magnetic properties. These findings will ultimately inform the optimization of B-F-O film deposition parameters for room-temperature memory applications.. 

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Planned Doctoral Research Activities:

 Fabrication of Ti and TiO2 buffer layers on:

 Fabrication of BFO films PLD on:

 Planned activities in 1st & 2nd  academic years include:

 Yttrium ferrite (YFeO3 ,YFO)/Ti/Si substrate

 YFO/TiO2/Si substrate

 Al2O3 & MgO substrates

 Planned activities in 3rd  & 4th  academic years include:

 Fabrication of thin BFO films by PLD on:

 Ti/Si substrate

 TiO2/Si substrate

 YFO/Al2O3 & YFO/MgO substrates

 Characterization films properties  using:

 Fabrication of thin BFO films PLD on:

 Characterization of films properties using:

  XPS, XRD, Raman, V-VASE, SEM, AFM, MFM, VSM.

  XPS, XRD, Raman, V-VASE, SEM, AFM, MFM, VSM.

  Si substrate by e-beam evaporator or magnetron sputtering.

Overview of Planned Doctoral Research Activities

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 Ph.D. Thesis Goal

Fúze obrys   Fabricate Thin Bismuth Ferrite (BiFeO3, BFO) Films: Create films on different substrates using pulsed laser deposition (PLD).  Property Characterization: Assess structural, chemical, optical, and magnetic properties.  Optimize for Devices: Fine-tune deposition parameters to improve BFO films for room-temperature memory applications.

[Audio] =====. SDE. Research Publications Instrument training Academics Internship. 

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Research Publications Instrument training Academics Internship

1. Introduction and Overview of BFO Properties

Crystal Structure:  BFO has a rhombohedral distorted perovskite structure (R3c space group), enabling spontaneous polarization.

 Multiferroic Ordering:  BFO bulk exhibits both ferroelectricity  (from Bi’s 6s lone pair electrons),  and antiferromagnetism  (from Fe’s 3d electrons).

 High Thermal Stability:  With high Curie (1103K) and Néel (643K) temperatures, BFO maintains multiferroic properties at room temperature.

Unique Properties of Thin BFO Films

 Enhanced Ferroelectric Polarization  

 Thin BFO films show stronger polarization than bulk BFO, driven by strain from substrate mismatch, which enhances atomic alignment and increases polarization.

 Increased polarization enhances memory devices and improves data storage speed.

 Weak Ferromagnetism  

 While bulk BFO has an AFM spin cycloid structure that cancels magnetism,  thin BFO films suppress this spin cycloid due to strain and thinness, resulting in weak FM.

 Weak FM is valuable for memory devices, combining magnetic and electric properties for improves data storage speed.

Fig. 1: Schematic representation of  spin Structures in BFO The left side shows BFO's cycloidal spin structure (ground state). Here, Fe spins form a spiral pattern, and their magnetic moments cancel out, resulting in no net magnetism.
 The right side shows collinear phase, where small distortions cause Fe spins to slightly tilt, or "cant," which creates weak FM.

[Audio] The objectives of this short thesis are to develop multiferroic thin B-F-O films, fabricate BFO/Ti/Si and BFO/TiO2/Si heterostructures, optimize B-F-O film crystallization quality, and comprehensively characterize the films' properties. The goal is to assess the magnetic behavior and determine the surface composition of the films, ultimately evaluating their potential for memory applications.. 

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2. Motivation and Objectives of Short Thesis

Objectives

 Develop Multiferroic Thin BFO Films

 Fabricate BFO/Ti/Si and BFO/TiO2/Si heterostructures:                (Use magnetron sputtering for Ti & TiO2 layers and PLD for BFO)

 Optimize BFO film crystallization quality by adjusting deposition parameters (temperature and oxygen pressure).

 Comprehensive Characterization

 Confirm crystal structure with XRD and Raman spectroscopy.

 Study surface morphology with SEM and AFM.

 Determine film thickness and analyze optical properties using ellipsometry.

 Assess Magnetic Behavior

 Measure magnetic properties to evaluate potential for memory applications using VSM and MFM.

 Determine surface composition with XPS.

1. Traditional Memory  

  Memory devices store data using binary states in regions called domains, where each domain represents either a 0 or a 1.

  States in traditional memory materials are switched by applying either a magnetic or electric field:  

  Magnetic Memory: Magnetic fields align magnetic particles within domains to represent 0 or 1.  

  Electric Memory: Electric fields adjust the charge or polarization in domains to represent 0 or 1.

 2. Next-Generation Memory 

 BFO has dual control because it combines both magnetic and electric properties, allowing state's switching via either field.

  Advantages:

  Switching with both fields increases data storage speed and efficiency.

  Electric fields use less energy, lowering power requirements for storage.

  Enhancing BFO with Heterostructures

  Creating BFO as a thin film on Si substrate with buffer layer enhances control over its properties:

  Strain and thinness can improve BFO’s electric and magnetic behaviors, enabling faster, more energy-efficient memory devices.

  This can make BFO heterostructure a promising choice for future high-performance storage solutions.

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[Audio] The fabrication process involves immersing substrates in a piranha solution to remove organics and particulates, followed by dipping in a diluted hydrofluoric acid solution to remove the oxide layer. The substrates are then rinsed with deionized water and dried with nitrogen gas. In the vacuum chamber, the Ar gas is introduced to create a stable environment for sputtering, with a sputtering pressure set to 1.5 × 10⁻³ mbar. The Ø2” Ti and TiO₂ targets are used, and the sputtering mechanics involve applying voltage to the targets.. 

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3. Methods: I. Thin Ti and TiO2 Layers Fabrication

Substrates were immersed in a 3:1 piranha solution of sulfuric acid (H₂SO₄) and hydrogen peroxide (H₂O₂) for 10 minutes to remove organics and particulates.

 Then were dipped in a 50:1 diluted Hydrofluoric Acid (2% HF) aqueous solution for 2 minutes to remove oxide layer.

 Substrates were rinsed with flowing deionized water to avoid recontamination from  any floating residues on water, then dried with nitrogen gas.

1. Vacuum and Gas Setup:

 Vacuum chamber was first evacuated to 4.3 × 10⁻8 mbar to remove residual gases and contaminants.

 Ar gas was then introduced to create a stable environment for sputtering, with a sputtering pressure set to  1.5 × 10⁻3 mbar.

 2. Target and Substrate Preparation:

 Ø2” Ti and TiO₂ targets were used  (Lesker GmbH, Germany). 

 3. Sputtering Mechanics:

 DC-generator (100 W) was used for Ti target,  while RF-generator (70 W) was used for TiO₂ target to prevent charge buildup.

 Voltage was applied to target (cathode), while substrate (anode) was positively charged.

 Ar atoms were ionized and directed to target, bombarding it and causing target atoms to be ejected, or “sputtered,” off into the plasma.

 4. Thin Film Deposition:

 Sputtered Ti or TiO₂ atoms traveled across chamber to land, deposit onto Si substrate, growing a thin film.

 Deposition times for 100 nm thickness were determine and set based on deposition rates measured by a quartz crystal microbalance     (QCM, "THS–21"):

 Ti Layer: Deposition rate of 0.30 ± 0.01 Å/s, requiring 55 minutes to reach 100 nm. TiO₂ Layer: Deposition rate of 0.05 ± 0.02 Å/s, requiring 5 hours and 55 minutes to reach 100 nm.

 Targets were pre-cleaned by sputtering to remove surface contaminants.

 Target-to-substrate distance was set and kept at 30 mm.

Smooth thin layer of Ti and TiO₂ were deposited by magnetron sputtering, (BESTEC GmbH, Germany), in argon (Ar) atmosphere at room temperature.

Before deposition, 5x5x0.5 mm Si substrates were cleaned as follows

Fig. 3: Fume hoods and PVD laboratory –magnetron sputtering system at CEITEC, alongside a schematic of sputtering chamber setup.

DC Sputtering: suitable for conductive materials. Non-conductive materials can take on a charge over time, causing arcing or "poisoning" of the target, potentially stopping sputtering.

RF Sputtering: suitable for non-conductive materials. Alternating radio frequency prevents charge buildup on the target, avoiding arcing issues.

[Audio] The fabrication of thin B-F-O films through P-L-D involves preparing the substrate and target materials. The substrate is attached to a sample holder using silver-based paint, heated to 120 degrees celsius to remove solvents and prevent contamination, and then mounted onto a laser heater mount. The target material is ground with abrasive paper to remove previous deposition tracks and ensure consistent results, and then mounted onto a carousel target mount. The P-L-D chamber is evacuated to a pressure of 4.8 × 10⁻⁸ mbar, and the distance between the target and substrate is set to 55 millimeters. The laser is aligned at a 45 degrees angle with a spot size of approximately 1.07 millimeters², and the energy entering the chamber is adjusted to achieve the desired laser fluence. Oxygen gas is introduced, and the butterfly valve is adjusted to reach a target background pressure between 0.013–0.13 mbar for each deposition. The substrate is heated to a temperature range of 450–640 degrees celsius using an IR heating laser, with the temperature monitored by a pyrometer. The laser is fired at a 5 Hz repetition rate with 10400 pulses, and the sample is gradually cooled to room temperature in the process gas by turning off the heater. The chamber is then vented, and the sample is removed from the P-L-D system.. 

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3. Methods – II. Thin BFO Films Fabrication

Substrate and Target Preparation: 

 1. Substrate was glued to  sample holder using silver-based paint. Then heated in air-furnace at 120°C for 10 minutes to evaporate solvents and prevent contamination.

 2. Prepared sample holder was mounted onto laser heater mount.

 3. Ceramic target surface was grinded with abrasive paper to remove previous deposition tracks and ensure reproducible ablation. Then mounted on carrousel target mount.

 Loading and Initial Setup:

 4. Heater and target mounts were loaded into PLD chamber, which was then evacuated to 4.8 × 10⁻⁸ mbar.

 5. Target-to-substrate distance was set to 55 mm.

 Laser, Pre-ablation, and Heating Settings:

 6. Laser was aligned at a 45° incidence angle to target, with a spot size of ~1.07 mm².

 7. Laser fluence was calculated to ~2 J/cm² by setting energy entering PLD chamber to ~19.8–22 mJ, as measured by energy meter.

 8. O2 gas was introduced, and butterfly valve was then adjusted to achieve a target background pressure between 0.013–0.13 mbar for each deposition.

 10. Substrate was heated to temperature range of 450–640°C using an IR heating laser, with temperature monitored by a pyrometer.

 Laser Firing and Deposition:

 11. laser was set to a 5 Hz repetition rate with 10400 pulses. 

 Cooling and Sample Removal:

 12. After laser firing stopped, sample was gradually cooled to room temperature in process gas by switching off heater.  

 13. Chamber was then vented, and sample was taken out of PLD system.

 - Beam was then periodically fired through optical components and focused through laser entry window onto target at a 45° angle. 

 - Each pulse smacked target at 45°; expanding as a plasma plume and creating a common plane of target, which may deliver target configuration of heated substrate.

PLD system (TSST, Netherlands) was used to grow BFO thin films  on prepared Ti/Si and TiO₂/Si substrates. 

 248 nm krypton fluoride (KrF) laser beam was used to ablate material from  a Ø2” Bi1.15FeO3 ceramic target with 15% excess Bi (SurfaceNet GmbH, Germany). 

 This process generated a plume of volatile material that condensed, deposited onto heated substrate.

PLD system includes several key components:   - Vacuum system with a main chamber that houses possessors of substrate and target, along with gas inlet valves.   - KrF excimer laser, equipped with a series of lenses and mirrors to focus beam onto target surface.   - Heater behind substrate possessor that uses a focused IR beam to illuminate sample holder, along with pyrometer.

Fig. 4: UHV-Cluster room–PLD system at CEITEC, alongside a schematic of its setup.

9. Pre-ablation was performed to clean target by closing substrate shutter and applying 1300 laser pulses at 3 Hz before each film growth series.

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 248 nm KrF laser Ti/Si orTiO2/Si Substrates Bi1.15FeO3 Target Plasma Plume  Heater 45° mirror reflects 99% of beam 45° mirror reflects 98% of beam, directing it through entry window to smack target at a 45° angle Plano-convex lens with a 452.3 mm focal length focuses beam onto target at a desired spot size
 Attenuator controls pulse energy Entry window causes an 8% energy loss

[Audio] The crystalline structure of several sets of B-F-O samples was confirmed using a Rigaku SmartLab 3 kilowatt diffractometer. The comparison of B-F-O film results with the reference pattern of the B-F-O target showed optimal conditions for the deposition of B-F-O thin films, resulting in a rhombohedral single-phase structure. Outside these optimal conditions, no crystalline structure was obtained, even with post-annealing. Within the optimal range, a small amount of Bi₂O₃ was detected due to excess Bi in the target. However, no secondary perovskite phases were observed. The detection of the reference B-F-O phase confirms the successful deposition of B-F-O thin films, validating their composition and contributing to their properties such as ferroelectricity and weak ferromagnetism.. 

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4. Characterizations and Key Results– I. XRD Structural Findings

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Crystalline  or no crystalline structure of several sets of BFO samples was confirmed using a Rigaku SmartLab 3kW diffractometer (Rigaku, Japan) with Cu Kα radiation at 40 kV and 30 mA.

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Fig. 7: Reference XRD pattern of our rhombohedral R3C Bi1.15FeO3 target with indexed reflections (hkl) compared to standard reference files from the Joint Committee on Powder Diffraction Standards (JCPDS).

Fig. 5:XRD system at CEITEC, alongside tow sets of BFO samples.

Diffraction patterns were recorded from 18° to 60° in 2θ−ω coupled scan mode with a parallel beam (PB) configuration, using a step size of 0.02° and a dwell time of 2s per step.

Fig. 6: XRD patterns of BFO films deposited on (a) Ti/Si and (b) TiO₂/Si substrates at 640°C and pressures of 0.013, 0.052, and 0.13 mbar. Peaks marked with (*) indicate Bi₂O₃ formation due to excess Bi in our Bi1.15FeO3  target.

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Comparisons of BFO film results with reference pattern of BFO target showed:

 Optimal Conditions: BFO thin films exhibited a rhombohedral single-phase structure when deposited at PO2 of 0.013-0.13 mbar and TS of 520-640°C.  

 Outside Conditions: No crystalline structure was obtained outside these conditions, even with post-annealing.

 Within Optimal Range: - Small amount of Bi₂O₃ was present due to excess Bi in target. 

                                          - No secondary perovskite phases (e.g., Bi₂Fe₄O₉, Bi₂₅FeO₃₉) were observed.

 Detection of reference BFO phase (intended BFO phase is present) confirms successful deposition of BFO thin films, validating their composition and contributing to properties like ferroelectricity and weak ferromagnetism.

XRD profiles of BFO films show differences between films deposited on Ti/Si and TiO₂/Si substrates:

 Effect of Substrates      (Ti vs. TiO₂ Layers): 

 BFO films on TiO₂/Si show sharper, well-defined peaks, indicating better crystallinity compared to films on Ti/Si. This suggests that TiO₂ provides a more matching template for crystallization.

 Impact of PO2                   (Low vs. High)

 Higher PO2  result in sharper peaks with higher intensities, indicating well-ordered crystalline structures with fewer defects due to improved oxygen incorporation during film growth.

 Effect of TS                (Low vs. High)

 Higher Temperatures result in more intense and sharper peaks, indicating improved crystallinity due to increased atomic mobility during film growth.

[Audio] The S-E-M and A-F-M images display the morphology and topography of various B-F-O samples grown on diverse substrates. The outcomes demonstrate that the selection of substrate substantially influences the development of B-F-O films. On Ti/Si, uniform, dense, larger, rounded grains with higher roughness and random orientation are acquired, whereas on TiO₂/Si, large, more columnar grains with high roughness and more oriented growth pattern are produced. The influence of PO₂ and TS on the growth of B-F-O films is also examined, revealing that higher PO₂ and TS result in better crystalline growth and larger grains. These discoveries offer valuable insights into the optimization of B-F-O film growth procedures.. 

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4. Characterizations and Key Results– II. SEM Morphology and AFM Topography Analysis

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Fig. 7: AFM and SEM images of BFO/Ti/Si thin films deposited at 520°C and 0.052 mbar.

Fig. 8: AFM and SEM images of BFO/TiO2/Si thin films deposited at 520°C and 0.052 mbar.

Morphology and topography of various BFO samples were analyzed using SEM-Verios 460L microscope (Thermo Fisher, Czech) and SPM-Bruker Dimension microscope (Icon®, USA).

SEM imaging was performed using SE mode at a 5 kV voltage with a beam current of 50 pA.

 20 μm²_AFM imaging was performed using a Si tip coated by CoCr, with a spring constant of 3 N/m, a frequency of 75 kHz, and a length of 225 µm.

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Growth of BFO and Underlying Layer:

 BFO on Ti/Si: Results in uniform, dense, larger, rounded grains with higher roughness and random orientation.

 BFO on TiO₂/Si: Produces large, more columnar grains with high roughness and more oriented growth pattern.

 Key Takeaways:

 Effect of Substrates (Ti vs. TiO₂ Layers)

 Ti Layer: Being metallic and conductive, it promotes large grain growth. It offers good adhesion and dense packing but lacks strong crystal orientation.

 TiO₂ Layer: As an insulating layer, it encourages columnar, more crystalline growth (due to potential lattice matching with BFO), resulting in large, well-oriented grains.

 Impact of PO₂ and TS:

 Higher PO₂ and TS: Lead to better crystalline growth, and larger grains

      - BFO films exhibit larger, columnar grains with higher roughness at higher PO₂ and TS, contrasting with smaller grains formed at lower conditions.

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[Audio] Slide 18: A research internship is planned for the upcoming years of the doctoral program. Slide 17: Lists of courses and academic activities in which I have participated. Slide 16: List of Instruments I have trained on. Slide 7: Description of research publications.. 

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4. Characterizations and Key Results– III. XPS Chemical Composition Analysis

- Spectral acquisition was conducted at approximately 2 × 10⁻⁹ mbar.

 - All XPS data were collected at a fixed tilt angle of 0°, giving a photoelectron takeoff angle of 90°, defined as the angle between the photoelectron's path to the spectrometer and the sample surface.

 - XPS survey spectra were recorded over a binding energy range of 0 to 1200 eV with an analyzer pass energy of 80 eV and a step size of 1 eV. High-resolution scans used a pass energy of 20 eV and a step size of 0.1 eV.

 -Data Analysis: Binding energy reference was calibrated using C 1s peak from adventitious carbon (AdC). Binding energies for all survey spectra, including core levels such as O 1s, Fe 2p, and Bi 4f, were aligned to hydrocarbon (C–C/C–H) peak in AdC at 284.80 eV.

Top layer of BFO samples was analyzed using XPS (AXIS Supra, Kratos Analytical Ltd., UK) to a depth of a few nanometers, using a focused monochromatic AlKα radiation source.

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Fig. 10: XPS wide spectra of BFO films deposited on (a) Ti/Si and (b) TiO₂/Si substrates at 640°C and a pressure of 0.013, 0.052, and 0.13 mbar mbar.

1. Constituent Elements (Bi, Fe, O):  

 Detection of Bi, Fe, O confirms successful deposition of BFO thin films, validating their expected composition and intended BiFeO3 phase.

 2. Carbon Presence:  

 C 1s peak in survey spectra indicates surface-adsorbed carbon, commonly from exposure to ambient air or sample preparation residues.  

 This surface carbon does not chemically impact physical properties of BFO films.

Impact of PO₂ on Film Composition:  

 Higher PO₂ conditions resulted in more stoichiometric films, and reduced oxygen vacancies.  

 Increased Bi and Fe content under high PO₂ suggests better preservation of BiFeO₃ phase.  

 In comparison, BFO/Ti/Si films show relatively lower Fe and Bi content than BFO/TiO₂/Si, indicating less stoichiometric growth.

at% of elements in BFO/Ti/Si deposited 640 °C


 PO2 %Fe %Bi %O 0.13 mbar 13.51 16.30 46.54 0.052 mbar 11.75 15.95 43.78 0.013 mbar 10.05 13.85 41.28

at% of elements in BFO/TiO2/Si deposited at 640 °C


 PO2 %Fe %Bi %O 0.13 mbar 14.92 18.11 46.50 0.052 mbar 12.98 16.47 43.70 0.013 mbar 10.95 14.94 41.95

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[Audio] The instrument training I received includes using the 10-ray Photoelectron Spectroscopy Kratos Analytical, which enables us to analyze the chemical composition of our samples. This technique is particularly useful for understanding the surface properties of materials, such as the presence of impurities or defects. By examining the 10-P-S spectra, we can determine the elemental composition of our samples and gain insights into their structural and electronic properties.. 

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Fig. 11: XPS high-resolution spectra for Bi 4f, Fe 2p, O 1s, and C 1s in BFO films deposited at 640°C and 0.13 mbar on (a) Ti/Si and (b) TiO₂/Si substrates.

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XPS analysis confirms that films consist of pure BiFeO₃ phase, with no detectable secondary BFO phases.  Deconvoluted spectra reveal: 

 - Bi 4f Spectrum: Shows two sharp peaks due to spin-orbit splitting are observed at 163.7 eV (Bi 4f₅/₂) and 158.3 eV  (Bi 4f₇/₂), align with trivalent state (Bi³⁺).

 - Fe 2p Spectrum: Presents two broad peaks at 710.6 eV (Fe 2p₃/₂) and 724.7 eV (Fe 2p₁/₂), corresponding to Fe³⁺ state in BFO, along with a satellite peak at ~719 eV, confirming Fe³⁺ as dominant oxidation state.

 - O 1s Spectrum: Split into two peaks, with one at 529.3 eV indicating lattice oxygen and another at 531.3 eV representing oxygen vacancies from surface defects.

 - C 1s Spectrum: Displays three peaks at 285.05 eV (hydrocarbon C–C/C–H), 286.57 eV (alcohol/ether C–OH/C–O–C), and 288.93 eV (ester carbonate O–C=O).

[Audio] The analysis of film thickness and optical constants using a NIR-UV spectroscopic ellipsometer reveals that the B-F-O film thickness is approximately 35 nanometers, with a roughness layer of around 7 nanometers. The study also highlights the impact of the underlying layer, with TiO2 supporting more uniform and smoother films compared to Ti. This is attributed to TiO2's stability as an oxide layer, promoting uniform film growth, better crystallinity, and fewer defects. In contrast, the Ti layer is less stable and prone to oxidation, leading to greater surface variability and interfacial reactions.. 

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4. Characterizations and Key Results– IV. SE Optical Properties

Film thickness and optical constants were analyzed using a NIR-UV spectroscopic ellipsometer (V-VASE, J. A. Woollam Co., USA).

To extract optical response of BFO films from ellipsometry data:

 Five-layer optical model was employed, consisting of ambient air, roughness, BFO film, buffer layer, and substrate. Surface roughness layer was modeled on a medium approximation mixed by 50% BFO and 50% voids.

 Absorption-free range below 3 eV was first utilized to estimate film thicknesses using a Cauchy relation. 

 Optical response of BFO films was simulated using a sum of four Gauss oscillators to extract film optical constants.

Fig. 12: SE at CEITEC, along with a schematic representation of optical model used.

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Fig. 13: Measured and fitted ellipsometry spectra (Ψ and Δ) for (a) BFO/TiO₂/Si and (b) BFO/Ti/Si films deposited at 0.013 mbar and 640°C.

1. Fit Quality  

  Both BFO/TiO₂/Si and BFO/Ti/Si systems show good model fits with experimental data, reflected in root mean square error (RMSE) values below 10, indicating that ellipsometry model well-captures films' optical properties.  

  For Constant Pulses, fitting process yielded BFO film thicknesses of 35 ± 7 nm and a roughness layer of 7 ± 3 nm, this aligns with AFM results.

 2. Impact of Underlying Layer (TiO₂ vs. Ti)  

  Ellipsometry plots highlight how substrate impacts BFO film growth, with TiO₂ supporting more uniform and smoother films compared to Ti:   

  BFO/TiO₂/Si: Smoother curve fit and consistent Ψ and Δ  variations suggest a more uniform BFO layer on TiO₂. This is attributed to TiO₂'s nature as stable oxide layer, promoting uniform film growth, better crystallinity, and fewer defects.  

  BFO/Ti/Si: Greater variability Ψ and Δ  curves indicates surface variability and interfacial reactions for Ti layer. This is attributed to metallic Ti may be less stable and prone to oxidation during deposition, causing more defects and a rough surface.

Ellipsometry spectra (Ψ and Δ) were measured for Ti (TiO2)/Si substrate, and BFO film at a 75° incidence angle across a photon energy range of 0.6 to 6.5 eV.

[Audio] Answer: The slides describe my academic activities and research experiences as a second-year Ph.D. student. According to Slide 18, a research internship is planned for the upcoming years of the doctoral program. On Slide 17, I listed the courses and academic activities I have participated in, including teaching physics to undergraduate students and participating in evaluating their bachelor's thesis presentations. Slide 16 shows the list of instruments I have trained on, including pulsed laser deposition, electron beam evaporator, and scanning probe microscope. Finally, Slide 7 provides a description of my research publications and instrument training, including characterizations and key results from my research.. 

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Fig. 14: (a) refractive index (n) and extinction coefficient (k) of BFO/TiO₂/Si and BFO/Ti/Si films deposited at 0.013 mbar and 640°C. Plots of  (b) (α∙E)² versus E, (c) (α∙E)1/² versus E. where α is absorption coefficient (α = 4πkE/1240) and E is photon energy.

1. Refractive Index (n)  

 For both BFO/Ti/Si and BFO/TiO₂/Si, n decreases with increasing photon energy, a typical behavior for BFO materials, where higher-energy photons interact less strongly.  

  n for BFO/TiO₂/Si is higher than that of BFO/Ti/Si across measured photon energy range, likely due to interfacial effects.

 2. Extinction Coefficient (k)  

  k, which relates to absorption properties, increases with higher photon energy, indicating stronger absorption at shorter wavelengths.  

  BFO/TiO₂/Si shows a slightly different absorption profile compared to BFO/Ti/Si, with higher values above 3eV range, likely due to interfacial effects.

Summary of Combined Effects for Constant # of Pulses

  Low PO₂ and TS: Films were thicker and rougher with higher defect density. This resulted in increased n (due to higher defects) and increased k (due to greater absorption from defects). Thus, Eg narrowed.

 High PO₂ and TS: Films were thinner and smoother with better crystalline quality. This resulted in decreased n (due to fewer defects) and decreased k (due to reduced absorption). Thus, Eg widens.

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[Audio] Magnetic properties and domain structures of various B-F-O samples were analyzed using a 5-S-M system and an MFM-Bruker Dimension microscope. The analysis revealed that BFO/TiO₂/Si film exhibits lower coercivity and higher remanence compared to BFO/Ti/Si film, indicating easier domain switching and better retention of magnetic alignment. This is attributed to the more aligned grains and domains in the former film. In contrast, the latter film shows higher coercivity and lower remanence, suggesting greater hindrance to domain switching and poor retention of magnetic alignment due to randomly oriented grains and irregular domains.. 

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4. Characterizations and Key Results– V. MFM & VSM Magnetic Properties

Magnetic properties and domain structures of various BFO samples were analyzed using a VSM system (Quantum Design VersaLab, USA) and an MFM-Bruker Dimension microscope (Icon®, USA).

MFM phase images of magnetic domain structure for BFO samples were captured in electrical and magnetic lift mode at room temperature using a silicon tip coated with magnetic CoCr (75 kHz). 

 - Film-only magnetization (emu/cm³) was calculated from recorded magnetic moment (emu) of films at 50, 300 K, using external magnetic field sweep from -2 T to +2 T. - Data was corrected by subtracting substrate contribution and normalizing by film volume.  - Loops exhibited partial saturation magnetization (Mₛ) of approximately ~6×10⁻⁵ emu/cm³.

Fig. 16: MFM images for (a) BFO/Ti/Si and (b) BFO/TiO₂/Si films deposited at 0.052 mbar and 580°C.

- BFO/Ti/Si Film: Shows large, irregular magnetic domains align with randomly oriented grains seen in AFM and SEM images. This structure may lead to high coercivity and hinder domain switching under external magnetic field (H).

 - BFO/TiO₂/Si Film: Shows elongated, more aligned magnetic domains, influenced by columnar grain structure and consistent alignment observed in AFM and SEM images. This may result in low coercivity and facilitate domain switching under external H.

 MFM images reveal regions with varying contrast, indicating well-defined magnetic domains that contribute to weak ferromagnetism.

- Both films exhibit temperature-dependent magnetic behavior, with a clear change in magnetization at 50K compared to 300K, indicating that temperature affects alignment and magnetic domains switching.

 - Correcting for paramagnetic contributions in BFO/Ti/Si films reveals a weak ferromagnetic character.

 - Correcting for diamagnetic contributions in BFO/TiO₂/Si films shows an enhanced, though still weak, ferromagnetic response compared to BFO/Ti/Si.

At 50K, BFO/TiO₂/Si film show: - Lower HC (100 Oe): Indicates easier domain switching.  - Higher Mr (~3.5×10⁻⁵ emu/cm³): Allows for better retention of magnetic alignment when external H is removed.  -These properties are corresponded to more aligned grains and domains  

 At 50K, BFO/Ti/Si film show: - Higher HC (200 Oe): Indicates greater hinder to domain switching.   - Lower Mr (~1.5×10⁻⁵ emu/cm³): Shows low ability to retain magnetic alignment  when external H is removed.  - These properties are linked to randomly oriented grains and irregular domains.

Impact of PO₂ and Tₛ on Magnetic Properties

 Higher PO₂ and Tₛ conditions led to:

 Improved Crystallinity and Orientation: Resulted in more aligned magnetic, narrower and more symmetric hysteresis loops, increased net magnetization and magnetic saturation values, lower coercivity, and higher remanence,.

  Reduced Defects: Fewer oxygen vacancies and defects enhanced magnetic contrast, producing larger, more continuous magnetic domains.

Fig. 17: Magnetization (emu/cm³) vs. magnetic field (kOe) for (a) BFO/Ti/Si and (b) BFO/TiO₂/Si films deposited at 0.052 mbar and 580°C.

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[Audio] The characterization of BFO/Ti/Si and BFO/TiO₂/Si films showed distinct variations in their structural and magnetic properties. Smaller, randomly oriented grains in BFO/Ti/Si films led to higher coercivity and lower remanent magnetization, whereas larger, columnar grains with better alignment in BFO/TiO₂/Si films resulted in lower coercivity and higher remanent magnetization. This disparity in grain structure and alignment has substantial implications for the suitability of these films for data storage applications.. 

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4. Characterizations and Key Results– VI. Conclusions

BFO/Ti/Si and BFO/TiO₂/Si films were prepared under controlled conditions (0.013-0.13 mbar, 520-640°C) and characterized using AFM, SEM, XPS, SE, MFM, VSM techniques, showing different structural and magnetic properties.

 - BFO/Ti/Si Films:  

 These films exhibited smaller, randomly oriented grains, leading to higher coercivity and lower remanent magnetization. 

 This results in inconsistent magnetic alignment and domain switching, making these films less suitable for data storage.

 - BFO/TiO₂/Si Films:  

 These films showed larger, columnar grains with better alignment, resulting in lower coercivity and higher remanent magnetization. 

 This enables more efficient domain switching and stable magnetic states storing, making these films more suitable for data storage, offering faster and more energy-efficient read/write operations.

A diagram of a cell

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Fig. 18: Schematic representations of key differences between BFO/Ti/Si and BFO/TiO₂/Si films: - Left (BFO/Ti/Si Film): Displays smaller, randomly distributed grains with blue arrows indicating random magnetic orientations. This reflects weaker magnetism, higher coercivity, and less stable magnetic domains. - Right (BFO/TiO₂/Si Film): Shows larger, aligned grains with red arrows indicating better magnetic alignment. This reflects stronger magnetism, lower coercivity, and more stable magnetic domains.

[Audio] =====. SDE. 2nd year Research Publications Instrument training Academics Internship. 

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2nd year Research Publications Instrument training Academics Internship

Overview of Contributions as Author & Co-Author

"Nanometer-Thick Titanium Film as a Silicon Migration Barrier“, authored by Saleh H. Fawaeera*, Wala’ M. Al-Qaisia, Vlasta Sedlákováb, Marwan S. Mousac, Alexandr Knápekd, Martin Truneca , and Dinara Sobolaa,e. Published in Materials Today Communications, Volume 40, August 2024, DOI: 10.1016/j.mtcomm.2024.109326. "Comprehensive Characterization of Different Metallic Films on Highly Oriented Pyrolytic Graphite Substrate“, authored by Kipkurui Ronoha*, Saleh H. Fawaeera, Vladimír Holcmanb, Alexandr Knápekc, and Dinara Sobolaa, d, published in the journal: Vacuum, Volume 215, September 2023, with the DOI: 10.1016/j.vacuum.2023.112345. "Exploring the Piezoelectric Properties of Bismuth Ferrite Thin Films Using Piezoelectric Force Microscopy: A Case Study“, authored by Misiurev, Da,*.; Kaspar, P.a,*; Sobola, D.a,b , Papež, N.a, Saleh H. Fawaeerb , Holcman, V.a, published in the journal: Materials, Volume 16(8), 3203; 18 April 2023, with the DOI: 10.3390/ma16083203.

Summary of involvement in  research works as both an author and co-author across different studies and projects.

"Properties of Bismuth Ferrite Heterostructures", authored by Saleh H. Fawaeera *, Wala’ M. Al-Qaisia, Vlasta Sedlakovab, Marwan S. Mousac , Alexandr Knàpekd, Martin Truneca, Dinara Sobolaa, e.  "Optical Properties of Yttrium Ferrite Films Prepared by Plasma Laser Deposition", which has been submitted to the Coatings Journal. This manuscript was co-authored by Dinara Sobola, Saleh H. Fawaeer, Pavla Kočková, Richard Shubert, Rashid Dallaev and Tomaš Trčka,

[Audio] Instruments I have been trained on include pulsed laser deposition, electron beam evaporator, magnetron sputtering system, 10-ray photoelectron spectroscopy, scanning probe microscope, Raman spectroscopy, 10-ray powder diffractometer, high-resolution scanning electron microscope, and cryogenic-free vibrating sample magnetometer. Additionally, I am scheduled to receive training in piezo response force microscopy and cryogenic-free electrical transport option measurement system in the near future. These instruments will enable me to conduct advanced research and analysis in my field of study.. 

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Knihy na polici se souvislou výplní 
 Instrument Training 1. Pulsed Laser Deposition TSST (PLD) 2. Electron Beam Evaporator BESTEC  3. Magnetron Sputtering System BESTEC  4. X-ray Photoelectron Spectroscopy Kratos Analytical  5. Scanning Probe Microscope Bruker Dimension Icon (ICON-SPM) 6. Raman Spectroscopy (Witec Alpha 300R) 7. X-ray Powder Diffractometer Rigaku SmartLab 3kW  8. High-Resolution Scanning Electron Microscope FEI Verios 460L 9. NIR-UV Spectroscopic Ellipsometer J. A. Woollam V-VASE   10.Cryogenic-free Vibrating sample magnetometer (VSM)- Quantum Design, VersaLab

Summary of instruments I have been trained on and an outline of upcoming training sessions.

Overview of Instrument Training & Upcoming Training

Upcoming Training 1.Piezo Response Force Microscopy (PFM) 2.Cryogenic-Free Electrical Transport Option (ETO) Measurement System – Quantum Design, VersaLab

[Audio] In my first year of the Ph.D. program, I participated in various courses and academic activities, including academic English for Ph.D. students, Friday seminars at CEITEC BUT, principles of nanoscience and nanotechnologies, advanced topics in nanotechnology, magneto-optical spectroscopy techniques, and spectroscopic methods for non-destructive diagnostics. I also taught physics to undergraduate students at fekt during the summer semester of the 2022/2023 academic year and evaluated their bachelor's thesis presentations under the guidance of Dr Mgr. Dinara Sobolova, Ph.D. Moreover, I attended several seminars and conferences, such as the 1-M-A-P-S Flash 2024 Conference, Advances in Magnetic Resonance International Workshop, A-M-N Seminar Series, fit4nano Workshop, STUDENT EEICT Conference, 10-P-S seminar, production of electronic devices based on thin films seminar, A-L-D for depositing films on complex geometries seminar, and another A-M-N Seminar Series. This experience has enabled me to establish a solid foundation in my field and broaden my understanding in various areas.. 

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DS444               Academic English for PhD 1& 2 DS446                Friday CEITEC BUT seminar 1& 2 DS113A             Principles of Nanoscience and Nanotechnologies DS116A            Advanced topics in nanotechnology DS126A            Magneto-Optical Spectroscopy Techniques DPC-FY2          Spectroscopic Methods for Non-Destructive Diagnostics 1CJ &1CK        Czech Language and Conversation 2CJ & 2CK       Czech Language and Conversation

Knihy na polici se souvislou výplní 
 Teaching Taught physics to undergraduate students at FEKT during summer semester of the 2022/2023 academic year. Participated in evaluating undergraduate students' bachelor's thesis presentations, under guidance of Dr. Mgr. Dinara Sobola, Ph.D., on June 15, 2022.

Knihy na polici se souvislou výplní 
 Seminars & Conferences IMAPS Flash 2024 Conference Advances in Magnetic Resonance International Workshop, 2024 AMN Seminar Series, 2024 FIT4NANO Workshop, 2024 STUDENT EEICT Conference, 2024 XPS seminar, 2023 Production of electronic devices based on thin films seminar, 2023 ALD for depositing films on complex geometries seminar, 2023 AMN Seminar Series, 2023

Overview of Coursework and Academic Activities

Summary of participation in various coursework and academic activities.

[Audio] In my doctoral program, a research internship is planned for the upcoming years, providing valuable hands-on experience and opportunities to apply theoretical knowledge in real-world settings.. 

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2nd year Research Publications Instrument training Teaching Internship

A research internship is planned for the upcoming years of the doctoral program.

Uživatelská síť se souvislou výplní

[Audio] This year, I will focus on documenting the results of my second-year research for publication, while also investigating the electrical transport, leakage behavior, and piezoelectric domains of BFO/Ti/Si and BFO/TiO₂/Si heterostructures using various characterization techniques. I will utilize optimal conditions from previous research to fabricate new heterostructures and characterize their properties.. 

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This year, I will continue planned research activities to meet set goals, including:

Documenting the results of 2nd year research for publication.

 Investigating electrical transport, leakage behavior, and piezoelectric domains of BFO/Ti/Si and BFO/TiO₂/Si heterostructures using PFM and ETO.

 Utilizing optimal conditions from previous research (2nd work) to fabricate BFO/YFO/Ti/Si and BFO/YFO/TiO₂/Si heterostructures. 

 Characterizing their structural, optical, chemical, electrical, and magnetic properties using XPS, XRD, Raman, AFM, MFM, PFM, VSM, SE, SEM and ETO techniques.

[Audio] As a researcher, I have had the opportunity to participate in various academic activities and courses throughout my academic journey. These include research publications, instrument training, teaching, and internship experiences. My research focuses on the development of novel materials and devices, and I have contributed to several publications in reputable scientific journals. I would like to express my gratitude to CEITEC BUT for providing the necessary resources and facilities for this research. I also acknowledge the financial support received from the CzechNanoLab project LM2023051 funded by meys CR. I would like to extend my appreciation to my supervisor, doc. Ing. Vlasta Sedláková, PH D , and co-supervisor, doc. Mgr. Dinara Sobola, Ph.D., for their guidance and support throughout my research.. 

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Saleh H. Fawaeer| CEITEC BUT
 tel: +420705921137
e-mail: 245196@vutbr.cz
 Office A1.18 Brno University of Technology
Central European Institute of Technology
Purkyňova 656/123, 612 00, Brno

Acknowledgments
 I am grateful to CEITEC BUT for providing the necessary resources and facilities for this research. “Financial support for measurements and sample fabrication at CEITEC Nano Research Infrastructure, through the CzechNanoLab project LM2023051 funded by MEYS CR, is gratefully acknowledged.” Special thanks to my supervisor, doc. Ing. Vlasta Sedláková, PH.D., co-supervisor, doc. Mgr. Dinara Sobola, Ph.D., for their guidance and support.

Doctoral research progress evaluation Academic year 

The slides presented above are my educational background, research publications, instrument training, academics, and internship experiences. In the second year of my Ph.D. program, I have published two research papers and completed training on various instruments such as pulsed laser deposition, electron beam evaporator, and scanning probe microscope. I also taught physics to undergraduate students and participated in evaluating their bachelor's thesis presentations. In the third year, I plan to participate in a research internship and continue my research on bismuth ferrite. I will also receive training on piezo response force microscopy and cryogenic-free electrical transport option measurement. My research focuses on characterizing the structural properties of bismuth ferrite using x-ray diffraction and other techniques. I have found that the material exhibits a crystalline structure, which is consistent with previous studies. I am excited about the opportunities ahead and look forward to contributing to the field of materials science.

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Fabrication of Ti and TiO2 buffer layers on various substrates will enable the growth of high-quality Bismuth Ferrite (B-F-O--) films. This planned activity includes the fabrication of Yttrium ferrite (YFeO3, Y-F-O--) buffer layers on Ti/Si and TiO2/Si substrates, as well as on Al2O3 and MgO substrates. The subsequent characterization of these films using 10-ray photoelectron spectroscopy (X-P-S--), 10-ray diffraction (X-R-D--), Raman spectroscopy, vacuum-vacuum atomic spectroscopy (V-VASE), scanning electron microscopy (S-E-M--), atomic force microscopy (A-F-M--), magnetic force microscopy (M-F-M--), and vibrating sample magnetometry (V-S-M--) will provide valuable insights into their structural, chemical, optical, and magnetic properties. These findings will ultimately inform the optimization of B-F-O film deposition parameters for room-temperature memory applications.

The objectives of this short thesis are to develop multiferroic thin B-F-O films, fabricate BFO/Ti/Si and BFO/TiO2/Si heterostructures, optimize B-F-O film crystallization quality, and comprehensively characterize the films' properties. The goal is to assess the magnetic behavior and determine the surface composition of the films, ultimately evaluating their potential for memory applications.

The fabrication process involves immersing substrates in a piranha solution to remove organics and particulates, followed by dipping in a diluted hydrofluoric acid solution to remove the oxide layer. The substrates are then rinsed with deionized water and dried with nitrogen gas. In the vacuum chamber, the Ar gas is introduced to create a stable environment for sputtering, with a sputtering pressure set to 1.5 × 10⁻³ mbar. The Ø2” Ti and TiO₂ targets are used, and the sputtering mechanics involve applying voltage to the targets.

The fabrication of thin B-F-O films through P-L-D involves preparing the substrate and target materials. The substrate is attached to a sample holder using silver-based paint, heated to 120 degrees celsius to remove solvents and prevent contamination, and then mounted onto a laser heater mount. The target material is ground with abrasive paper to remove previous deposition tracks and ensure consistent results, and then mounted onto a carousel target mount. The P-L-D chamber is evacuated to a pressure of 4.8 × 10⁻⁸ mbar, and the distance between the target and substrate is set to 55  millimeters. The laser is aligned at a 45 degrees angle with a spot size of approximately 1.07  millimeters², and the energy entering the chamber is adjusted to achieve the desired laser fluence. Oxygen gas is introduced, and the butterfly valve is adjusted to reach a target background pressure between 0.013–0.13 mbar for each deposition. The substrate is heated to a temperature range of 450–640 degrees celsius using an IR heating laser, with the temperature monitored by a pyrometer. The laser is fired at a 5 Hz repetition rate with 10400 pulses, and the sample is gradually cooled to room temperature in the process gas by turning off the heater. The chamber is then vented, and the sample is removed from the P-L-D system.

The crystalline structure of several sets of B-F-O samples was confirmed using a Rigaku SmartLab 3 kilowatt diffractometer. The comparison of B-F-O film results with the reference pattern of the B-F-O target showed optimal conditions for the deposition of B-F-O thin films, resulting in a rhombohedral single-phase structure. Outside these optimal conditions, no crystalline structure was obtained, even with post-annealing. Within the optimal range, a small amount of Bi₂O₃ was detected due to excess Bi in the target. However, no secondary perovskite phases were observed. The detection of the reference B-F-O phase confirms the successful deposition of B-F-O thin films, validating their composition and contributing to their properties such as ferroelectricity and weak ferromagnetism.

The S-E-M and A-F-M images display the morphology and topography of various B-F-O samples grown on diverse substrates. The outcomes demonstrate that the selection of substrate substantially influences the development of B-F-O films. On Ti/Si, uniform, dense, larger, rounded grains with higher roughness and random orientation are acquired, whereas on TiO₂/Si, large, more columnar grains with high roughness and more oriented growth pattern are produced. The influence of PO₂ and TS on the growth of B-F-O films is also examined, revealing that higher PO₂ and TS result in better crystalline growth and larger grains. These discoveries offer valuable insights into the optimization of B-F-O film growth procedures.

Slide 18: A research internship is planned for the upcoming years of the doctoral program. Slide 17: Lists of courses and academic activities in which I have participated. Slide 16: List of Instruments I have trained on. Slide 7: Description of research publications.

The instrument training I received includes using the 10-ray Photoelectron Spectroscopy Kratos Analytical, which enables us to analyze the chemical composition of our samples. This technique is particularly useful for understanding the surface properties of materials, such as the presence of impurities or defects. By examining the 10-P-S spectra, we can determine the elemental composition of our samples and gain insights into their structural and electronic properties.

The analysis of film thickness and optical constants using a NIR-UV spectroscopic ellipsometer reveals that the B-F-O film thickness is approximately 35 nanometers, with a roughness layer of around 7 nanometers. The study also highlights the impact of the underlying layer, with TiO2 supporting more uniform and smoother films compared to Ti. This is attributed to TiO2's stability as an oxide layer, promoting uniform film growth, better crystallinity, and fewer defects. In contrast, the Ti layer is less stable and prone to oxidation, leading to greater surface variability and interfacial reactions.

Answer: The slides describe my academic activities and research experiences as a second-year Ph.D. student. According to Slide 18, a research internship is planned for the upcoming years of the doctoral program. On Slide 17, I listed the courses and academic activities I have participated in, including teaching physics to undergraduate students and participating in evaluating their bachelor's thesis presentations. Slide 16 shows the list of instruments I have trained on, including pulsed laser deposition, electron beam evaporator, and scanning probe microscope. Finally, Slide 7 provides a description of my research publications and instrument training, including characterizations and key results from my research.

Magnetic properties and domain structures of various B-F-O samples were analyzed using a 5-S-M system and an MFM-Bruker Dimension microscope. The analysis revealed that BFO/TiO₂/Si film exhibits lower coercivity and higher remanence compared to BFO/Ti/Si film, indicating easier domain switching and better retention of magnetic alignment. This is attributed to the more aligned grains and domains in the former film. In contrast, the latter film shows higher coercivity and lower remanence, suggesting greater hindrance to domain switching and poor retention of magnetic alignment due to randomly oriented grains and irregular domains.

The characterization of BFO/Ti/Si and BFO/TiO₂/Si films showed distinct variations in their structural and magnetic properties. Smaller, randomly oriented grains in BFO/Ti/Si films led to higher coercivity and lower remanent magnetization, whereas larger, columnar grains with better alignment in BFO/TiO₂/Si films resulted in lower coercivity and higher remanent magnetization. This disparity in grain structure and alignment has substantial implications for the suitability of these films for data storage applications.

Instruments I have been trained on include pulsed laser deposition, electron beam evaporator, magnetron sputtering system, 10-ray photoelectron spectroscopy, scanning probe microscope, Raman spectroscopy, 10-ray powder diffractometer, high-resolution scanning electron microscope, and cryogenic-free vibrating sample magnetometer. Additionally, I am scheduled to receive training in piezo response force microscopy and cryogenic-free electrical transport option measurement system in the near future. These instruments will enable me to conduct advanced research and analysis in my field of study.

In my first year of the Ph.D. program, I participated in various courses and academic activities, including academic English for Ph.D. students, Friday seminars at CEITEC BUT, principles of nanoscience and nanotechnologies, advanced topics in nanotechnology, magneto-optical spectroscopy techniques, and spectroscopic methods for non-destructive diagnostics. I also taught physics to undergraduate students at fekt during the summer semester of the 2022/2023 academic year and evaluated their bachelor's thesis presentations under the guidance of Dr  Mgr. Dinara Sobolova, Ph.D. Moreover, I attended several seminars and conferences, such as the 1-M-A-P-S Flash 2024 Conference, Advances in Magnetic Resonance International Workshop, A-M-N Seminar Series, fit4nano Workshop, STUDENT EEICT Conference, 10-P-S seminar, production of electronic devices based on thin films seminar, A-L-D for depositing films on complex geometries seminar, and another A-M-N Seminar Series. This experience has enabled me to establish a solid foundation in my field and broaden my understanding in various areas.

In my doctoral program, a research internship is planned for the upcoming years, providing valuable hands-on experience and opportunities to apply theoretical knowledge in real-world settings.

This year, I will focus on documenting the results of my second-year research for publication, while also investigating the electrical transport, leakage behavior, and piezoelectric domains of BFO/Ti/Si and BFO/TiO₂/Si heterostructures using various characterization techniques. I will utilize optimal conditions from previous research to fabricate new heterostructures and characterize their properties.

As a researcher, I have had the opportunity to participate in various academic activities and courses throughout my academic journey. These include research publications, instrument training, teaching, and internship experiences. My research focuses on the development of novel materials and devices, and I have contributed to several publications in reputable scientific journals. I would like to express my gratitude to CEITEC BUT for providing the necessary resources and facilities for this research. I also acknowledge the financial support received from the CzechNanoLab project LM2023051 funded by meys CR. I would like to extend my appreciation to my supervisor, doc. Ing. Vlasta Sedláková, PH D , and co-supervisor, doc. Mgr. Dinara Sobola, Ph.D., for their guidance and support throughout my research.