Microstructure Regulation and Optoelectronic Performance Optimization of Flexible CPI-Based ITO Thin Films Under Low-Temperature Heat Treatment Process
Round 1
Reviewer 1 Report
Comments and Suggestions for AuthorsThe authors conducted an interesting study on a relevant topic. The scope of the experimental work is impressive. However, while reading the article, a number of questions and suggestions for the authors arose, which are listed below.
1. The introduction to the article contains very few references to works on the topic of the research. Moreover, most of the cited literature is more than 5 years old. It is necessary to supplement the "Introduction" section with references to more recent works devoted to the study of various nanomaterials as flexible and transparent films for optoelectronic devices. In particular, it is necessary to consider examples of the use of carbon nanostructures for such applications. References to Nanomaterials 2023, 13(15), 2249; Surfaces and Interfaces Volume 24, June 2021, 101137; Nanomaterials. 2021. Vol. 11, no. 8. P. 1934 will make the introduction section more informative.
2. The authors should provide a more detailed discussion in the text of the physical reason for the small increase in resistance at a temperature of 150 degrees Celsius (line 150).
3. How was the optical band gap of the films reported on page 5 (lines 160-162) determined? Energy band diagrams should be provided to confirm the increase in the band gap from 3.75 eV to 3.92 eV.
4. The sentence "The relationship of the resistivity and transmittance of the ITO films 141" is shown in Figure 4 below: on page 5 (lines 141-142) should be supplemented with a reference to Figure 5, since Figure 4 only shows the dependence of O resistivity vs. deposition temperature.
5. The symbol "反而" on page 5 (line 149) should be clarified or corrected if necessary.
6. Figure 6 is of very poor quality and should be replaced.
Author Response
Comments 1.The introduction to the article contains very few references to works on the topic of the research. Moreover, most of the cited literature is more than 5 years old. It is necessary to supplement the "Introduction" section with references to more recent works devoted to the study of various nanomaterials as flexible and transparent films for optoelectronic devices. In particular, it is necessary to consider examples of the use of carbon nanostructures for such applications. References to Nanomaterials 2023, 13(15), 2249; Surfaces and Interfaces Volume 24, June 2021, 101137; Nanomaterials. 2021. Vol. 11, no. 8. P. 1934 will make the introduction section more informative.
Response 1.Thank you for pointing this out,Therefore, we have enhanced the background of the Introduction by adding key application-oriented references (see Lines 60~67).
Comments 2.The authors should provide a more detailed discussion in the text of the physical reason for the small increase in resistance at a temperature of 150 degrees Celsius (line 150).
Response 2. We thank the reviewer for this insightful comment. The text in Section 3.4.3.1（line 247~250） has been revised to provide a detailed discussion on the physical reason for the small resistance increase at 150 °C. We now explain that this is likely due to the onset of minor grain boundary scattering or the desorption of adsorbed oxygen, which can reduce the carrier concentration. The term 'Hall effect' has also been corrected in this section to accurately describe the measurement mechanism.
Comments 3. How was the optical band gap of the films reported on page 5 (lines 160-162) determined? Energy band diagrams should be provided to confirm the increase in the band gap from 3.75 eV to 3.92 eV.
Response 3. We have removed the statement
Comments 4.The sentence "The relationship of the resistivity and transmittance of the ITO films 141" is shown in Figure 4 below: on page 5 (lines 141-142) should be supplemented with a reference to Figure 5, since Figure 4 only shows the dependence of O resistivity vs. deposition temperature.
Response 4. We appreciate the reviewer for catching this inconsistency. The text has been thoroughly revised and reorganized for clarity. The sentence in question now correctly references Figure 5, and the discussion on the relationship between resistivity and transmittance has been consolidated in Sections 3.3 and 3.4.1 (Pages 8-9 lines236~259 ).
Comments 5.The symbol "反而" on page 5 (line 149) should be clarified or corrected if necessary.
Response 5: I have made the corrections as requested.
Comments 6. Figure 6 is of very poor quality and should be replaced.
Response 6: Thank you for pointing this out. Figure 6 has been replaced with a new, high-quality version with improved resolution and clarity（figure 10 line 344）.
Author Response File: 
Author Response.pdf
Reviewer 2 Report
Comments and Suggestions for AuthorsI agree publishing the manuscript entitled “Microstructure Regulation and Optoelectronic Performance Optimization of Flexible CPI-Based ITO Thin Films under Low-Temperature Heat Treatment Process” after making some changes:
- There are many editing errors (e.g. row 149,202-204, 307…)
- There should be a rearrangement of the results in the manuscript, namely Structure, Morphology, Optical properties, Electrical propertiesetc.
- Table 1 should be moved to the preparation point and the paragraph rearranged.
- For XRD analysis, figures 7a and 8 should be merged in one figure, and then figure 7b should become a separate figure: Figure 8 (Variation of peak intensity ratio for each crystal plane of ITO)
- Figure caption 9 must contain the explanation of each figure: (a) 150°C, as-deposited (b) 190°C, as-deposited (c) 230°C, as-deposited, (d) 150°C, annealing (e) 190°C, annealing (f) 230°C. Also add a scale-bar in each image to understand the scale. All AFM images must have equal dimensions in X-Y, otherwise they are distorted.
- SEM results are missing from the manuscript but the authors mention analysis. SEM should be added to the paper
- Related to the Transmission results, how was calculated the optical band gap (Eg); If obtained from the transmission, should add the corresponding equation.
- Please mention how was determined the film thickness of the ITO (method, etc).
- Hall-effect-measurement: the electrical constants (carrier concentration, mobility) mentioned in the manuscript, depending on the temperatures, should be added in the form of tables along with the film thickness and energy
- Bending Resistance Study - to add a table with the results for ΔR/R₀, with a temperature (e.g. 20000 cycles).
The work needs to be restructured so that it can be easily followed
Comments on the Quality of English LanguageThe English could be improved to more clearly express the research.
Author Response
Comment 1:There are many editing errors (e.g. row 149,202-204, 307…)
Response 1:Thank you for pointing this out. We have carefully proofread the entire manuscript and corrected all editing errors, including those in the mentioned rows. The language has been polished for better clarity and accuracy throughout the text.
Comment 2:There should be a rearrangement of the results in the manuscript, namely Structure, Morphology, Optical properties, Electrical properties etc.
Response 2:We agree with this suggestion. The "Results and Discussion" section has been reorganized accordingly:
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3.1. Structural Properties
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3.2. Surface Morphology
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3.3. Optical Properties
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3.4. Electrical Properties
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3.5. Bending Resistance
This restructuring improves the logical flow and readability of the manuscript.
Comment 3:Table 1 should be moved to the preparation point and the paragraph rearranged.
Response 3:Thank you for this suggestion. We have moved Table 1 to Section 2.1 ("CPI Substrate and ITO Film Preparation") and integrated it with the relevant text describing the deposition parameters (Page 4 line 103).
Comment 4:For XRD analysis, figures 7a and 8 should be merged in one figure, and then figure 7b should become a separate figure: Figure 8 (Variation of peak intensity ratio for each crystal plane of ITO)
Response 4：Thank you for this suggestion. We have merged the original Figures 7a and 8 into a new Figure 4a（line 130）, which presents the XRD patterns of ITO films deposited at different substrate temperatures both before and after annealing. Regarding Figure 7b (now Figure 4b), we have retained it in its original position following Figure 4a because it provides direct analysis and interpretation of the peak intensity trends shown in Figure 4a. Keeping these figures adjacent maintains the logical flow of discussion, where the data presentation is immediately followed by its corresponding analysis, which we believe enhances reader comprehension of the crystallographic evolution. This arrangement allows for clearer interpretation of how deposition temperature affects crystal plane preferences in ITO films.
Comment 5:Figure caption 9 must contain the explanation of each figure: (a) 150°C, as-deposited (b) 190°C, as-deposited (c) 230°C, as-deposited, (d) 150°C, annealing (e) 190°C, annealing (f) 230°C. Also add a scale-bar in each image to understand the scale. All AFM images must have equal dimensions in X-Y, otherwise they are distorted.
Response 5:We have updated the AFM figure（line 205）.
Comment 6:SEM results are missing from the manuscript but the authors mention analysis. SEM should be added to the paper.
Response 6: We have removed the statement.
Comment 7:
Related to the Transmission results, how was calculated the optical band gap (Eg); If obtained from the transmission, should add the corresponding equation.
Response 7:We have removed the statement.
Comment 8:Please mention how was determined the film thickness of the ITO (method, etc).
Response 8:We have specified the method for thickness measurement in Section 2.1 (Page 4, Line 99):
"The film thickness was precisely controlled at 30±2 nm, as confirmed by a surface profilometer (Dektak XT, Bruker)."
Comment 9:Hall-effect-measurement: the electrical constants (carrier concentration, mobility) mentioned in the manuscript, depending on the temperatures, should be added in the form of tables along with the film thickness and energy.
Response 9:We have consolidated the electrical parameters (carrier concentration, mobility, resistivity, thicknessinto a new Table 4 in Section 3.4.1 (Page 10 line 259).
Comment 10:Bending Resistance Study - to add a table with the results for ΔR/R₀, with a temperature (e.g. 20000 cycles).
Response 10:We have added a new Table 5 in Section 3.5 (Page 13 line 332), summarizing the ΔR/R₀ values at different bending cycles for various substrate temperatures.
We believe that all concerns raised by the reviewers have been adequately addressed in the revised manuscript. Thank you once again for the valuable feedback.
Sincerely,
The Authors
Author Response File: Author Response.pdf
Round 2
Reviewer 1 Report
Comments and Suggestions for AuthorsThe authors of the article thoughtfully responded to the comments made and carried out careful work to improve the quality of the manuscript. Fragments added to the text of the article help to better perceive the results obtained by the author. As minor comments, we can note errors in the formatting of two references. In the reference at number 14, the article Nanomaterials 2021, 11(8), 1934 has a title of other authors, namely Slepchenkov, M.M.; Barkov, P.V.; Glukhova, O.E. Hybrid Films Based on Bilayer Graphene and Single-Walled Carbon Nanotubes: Simulation of Atomic Structure and Study of Electrically Conductive Properties. The reference number 15 does not indicate the name of the journal. Should be Materials & Design. Otherwise, the manuscript is ready for publication.
Author Response
Comment 1:In the reference at number 14, the article Nanomaterials 2021, 11(8), 1934 has a title of other authors, namely Slepchenkov, M.M.; Barkov, P.V.; Glukhova, O.E. Hybrid Films Based on Bilayer Graphene and Single-Walled Carbon Nanotubes: Simulation of Atomic Structure and Study of Electrically Conductive Properties.”
Response:We sincerely apologize for the oversight. The reference has been corrected to accurately reflect the correct authors and title as follows（line 417~418）:
Slepchenkov, M.M.; Barkov, P.V.; Glukhova, O.E. Hybrid Films Based on Bilayer Graphene and Single-Walled Carbon Nanotubes: Simulation of Atomic Structure and Study of Electrically Conductive Properties[J]. Nanomaterials 2021, 11, 1934.
Comment 2:The reference number 15 does not indicate the name of the journal. Should be Materials & Design.”
Response:Thank you for pointing out this omission. We have now included the full journal name in Reference 15(line 419~420):
[15] Yi Shen, Zhaochang Feng, Hanyan Zhang. Study of indium tin oxide films deposited on colorless polyimide film by magnetron sputtering. Materials & Design 2020, Volume 193, 108809.
We have verified all other references and ensured their accuracy and consistency with the journal’s formatting guidelines.
Thank you once again for your valuable time and insightful suggestions, which have helped us further improve the manuscript. We hope that the revised version now meets the journal’s standards for publication.
Sincerely,
Han yan Zhang
Author Response File: Author Response.pdf
