Influence of an MgTiTaON Inserted Layer on Magnetic Properties and Microstructure of FePtAgC Films
Round 1
Reviewer 1 Report
The current manuscript on the magnetic properties of FePtAgC films grown by magnetron sputtering technique with an interleaved MgTiTaON layer by Jai-Lin Tsai et al is an interesting study in the area of magnetic FePt thin film and their applications. I suggest the authors to address the following points in the manuscript to add to the quality of the paper to meet the journal standards.
1. I suggest the authors to add more introduction on the FePt thin film growth and magnetic properties giving an overview of a broad perspective of the subject with the significance and origin of the idea presented in the manuscript in the context of insertion of MgTiTaON layer for FePtAgC thin film growth. Adding a critical review of the current state of research with relevant citations is suggested.
2. The materials synthesis section looks way too precise to describe the work. I suggest the authors to add more information on the materials synthesis and characterization techniques in detail. Details of the sputtering instrument, targets, pre-treatments of the substrates etc., and TEM thin-film sample preparation and imaging techniques.
3. I suggest the authors to add discussion on the origin of magnetism & coercivity and the underlying physics with relevant citations. Add a Table listing all the samples, composition, targeted thickness, surface roughness, magnetization, coercivity etc.
4. Figure 7 showing HAADF-EDX elemental mapping is poor in quality. I suggest the authors to provide high-quality maps represented with visible bright colors. The colors represented in the legends and that used in the EDX mappings doesn´t match. For example in Fig. 7(b).
5. I suggest the authors to improve the language, grammar and spellings including those in the figure legends.
Author Response
Dear Editor,
Please see the attachment. Thanks
best,
Jai-Lin
Author Response File: 
Author Response.pdf
Reviewer 2 Report
Too many words in the text. The paper should have at least two tables showing material parameters, magnetic and crystallographic information.
I would encourage the authors to either show the multilayer configuration in detail or cite the relevant paper if its available to view there.
These authors have a serious problem in writing, all of the information is crammed together in big paragraphs. It is like preparing a curry using meat, fruits, vegetables, sugar, and chilli. Imagine the quality of the curry so prepared. Authors should break down long paragraphs into clear and short ones to assist readers and improve the quality of their paper. The author might need help from either their native speaker colleague or MDPI proof-reading services.
The introduction section does not state anything about what the authors are going to do in rest of the paper\ except one sentence “inserting14 nm FePt(Ag,C) to obtain taller FePt grains”. For the introduction style, see the paper on perpendicular magnetic anisotropy and microstructure studies in a similar field as:
2017 J. Phys. D: Appl. Phys. 50 355002; https://iopscience.iop.org/article/10.1088/1361-6463/aa7c5b/meta
Grammatical and error mistakes are located in many places. The author should carefully read the manuscript to avoid errors and typo. Replace by “Full width at half maximum (FWHM)” for full width half maximum.
The conclusion section does not include any significant summary of the research. Include quantitative conclusion of the work.
“A conclusion is like the final chord in a song. It makes the listener feel that the piece is complete and well done. The same is true for your audience. You want them to feel that you supported what you stated in your thesis. You then become a reliable author for them, and they are impressed by that and will be more likely to read your work in the future. They may also have learned something and maybe have had their opinion changed by what you have written or created!”- Random Sources.
Revise the conclusion section.
Author Response
Dear Editor,
Please see the attachment. Thank you.
best
Jai-Lin
Author Response File: Author Response.pdf
Reviewer 3 Report
Dear Editor,
The manuscript entitled "Influence of MgTiTaON Inserted Layer on Magnetic Properties and Microstructure of FePtAgC Films" by Tsai and co-workers, reports on the sputter deposition of FePt thin films having thickness greater than 10 nm; the main materials engineering advancement of this work concerns the use of MgTiTaON inserted ultra-thin films for maintaining the desired L10 crystal structure. The effect of Ag and C co-sputtering is also investigated, in view of the proposed MgTiTaON inserted FePt thin films. The crystallographic, morphological, and magnetostatic properties of the films are presented. The study is conducted according to scientific standards, the findings of the work are interesting and well-presented and the conclusions are supported by the data. This systematic investigation provides important information for the Materials Scientist that wishes to develop such L10 FePt films for energy-assisted magnetic recording applications. I recommend publishing the article after some minor revisions are taken into account.
The issues to be taken into account are the following:
1. English – throughout the manuscript – requires improvement.
2. In lines 68-69, the authors say: “…and the c-axis of FePt layer was almost oriented perpendicular to the film surface”. From where do the authors infer this conclusion? If from rocking curves, representative ones should be shown.
3. In figure 1(f) the authors should add a mark indicating the FePt (200) Bragg peak
4. In lines 77-78, the authors say: “…the FePt film with total thickness 14 nm (t=6) shows lower degradation”. How do they define “degradation”; this sentence needs to be more precise and clear.
5. In figures 2(a) and (b) the authors should add error bars, or mention the error of the measurements in the text.
6. In figure 2(a) the authors show a decrease of out-of-plane coercivity as thickness increases and the authors say (in lines 87-88) “…that the FePt ordering degree slightly decreases with the FePt total thickness”. However, from the cross-sectional TEM image in figure 6(a), it is apparent that some FePt columns are composed of more than one grain, since FePt grains of lower thickness grow on top. In the past, it has been reported that as film thickness decreases, occurs a reorientation of the magnetic anisotropy axis of FePt films towards the in-plane direction, due to the decrease of the chemical ordering parameter (“Magnetic anisotropy axis reorientation at ultrathin FePt films”, Andreas Kaidatzis, Vassilis Psycharis, Georgios Giannopoulos, José Miguel García-Martín, and Dimitrios Niarchos, Phys. Status Solidi RRL, 1–4 (2016), DOI 10.1002/pssr.201600386). The authors should comment the possibility of thus creating a hard/soft fct/fcc composite of lower coercivity.
7. The authors should check the scale bars in the TEM and AFM images shown; e.g. in figure 6, the average grain size is approximately between 6 nm and 10 nm, but in the cross-sectional TEM images the grain size seems considerably bigger.
8. In line 139 the figure referred to must be figure 5(b).
9. In lines 141-142 the authors say: “In Fig. 6(a), the FePt grains are connected but the capping is the worm-like structure”. This sentence is not clear; it should be more precise. Also, the authors should correct “dorm-like” to “worm-like”.
–
Sincerely yours,
Author Response
Dear Editor,
Please see the attachment. Thank you.
best
Jai Lin
Author Response File: Author Response.pdf
Round 2
Reviewer 1 Report
I thank the authors for addressing all the suggested improvements. The manuscript can now be accepted for publication.
Please carefully check all the spellings and grammar in the overall text.
Reviewer 2 Report
The paper has improved but grammatical mistakes are still present in the paper.
Abstract: "After high-temperature deposition at 470oC, the granular 12 FePt(Ag, C, MgTiTaON) film was illustrated perpendicular magnetization and the out-of-plane 13 coercivity (Hc) was increased with (Ag, C) segregants and the highest Hc is 18.3kOe when x= 40." The verb "was" is unnecessary.
Conclusion:
"who" is reserved for a person, and not for a "MgTiTaON interlayer". A careful and thorough proof-reading is a must. Replace "who" by "which" or similar words.
