Two-Step Polishing Technique for Flat and Smooth Copper Substrates by Electrochemical and Chemical Etching

Round 1

Reviewer 1 Report

Comments and Suggestions for Authors

This paper proposed a two-step polishing chain that uses controllable electrochemical and chemical etching to correct the shape error of the workpiece. The research topic is interesting, however, there are many issues in the manuscript.

1. In the "Introduction" section, the authors are advised to clearly elaborate on the research gaps in the current application of the proposed technology.
2. The references cited in the manuscript have been published for too long. None of the relevant papers published in the past three years have been cited. This is a part that must be revised.
3. Line 181. What is the basis for the third assumption when building the model?
4. Please provide detailed information on the software (such as Comsol) and experimental setup of Jet-ECM and EGCP used in the manuscript, including version, model, and place of origin.
5. In section 2.2, there is a lack of introduction to the modeling details using Comsol software.
6. What role do the results of numerical analysis in section 2.2 provide for subsequent experiments?
7. What is the basis for determining the experimental parameter values in Tables 2 and 3?
8. What are the other process parameter conditions besides voltage variation in the experimental results of Figure 8? Both Figure 10 and Figure 12 have the same issue. Please refer to the experimental values shown in Table 2.
9. The so-called parameter optimization in section 4.1 is unreasonable, including the conclusion obtained at the end of this section. From the perspective of experimental design, this is a single factor experiment and cannot achieve optimization of process parameter combinations.
10. The conclusion can summarize the issues that still need further exploration in current research.

Author Response

Please see the attachment.

Author Response File: Author Response.pdf

Reviewer 2 Report

Comments and Suggestions for Authors

The work is interesting an innovative and it provides valuable information about the process. Nevertheless, the explanation of the process is not clear and the English of some sentences is incorrect.

1. The justification of the electrolyte used is not given. Acid electrolytes can corrode the equipment used and lacks sustainability.
2. The etching analysis of EGCP is not clear. It is said that the ions Fe2+ are oxidized to Fe3+ in the Working Electrode, which is the cathode, but oxidation cannot take place in the cathode but only in the anode. The cathode is the place for the reduction. In addition, the diffusion of the ions is proposed as the mechanism for the transfer of ions from the cathode to the anode, but the electrical attraction makes it impossible that the ions part from the cathode.

Comments on the Quality of English Language

1. The use of English is incorrect in some expressions, for example in page 4, line 127, the expression "leads to the formation of the viscous film relatively difficult" should be expressed like this "leads to the formation of the viscous film with relative difficulty". In page 13, line 376, the expression "However, MSF error generates, significantly" should be corrected, since the verb generate is transitive. It should be expressed like this "However, MSF error arises, significantly".
2. The meaning of "moving speeds" in page 11, line 327 is not clear. It is not stated whether the speed is variable or changes with the experiment.

Author Response

Please see the attachment.

Author Response File: Author Response.pdf

Round 2

Reviewer 1 Report

Comments and Suggestions for Authors

The authors made appropriate revisions based on the review comments.

Reviewer 2 Report

Comments and Suggestions for Authors

I verified that the incorrect expressions have been corrected and that ambiguous sentences have been clarified.

Comments on the Quality of English Language

1. The use of English is incorrect in some expressions, for example in page 4, line 127, the expression "leads to the formation of the viscous film relatively difficult" should be expressed like this "leads to the formation of the viscous film with relative difficulty". In page 13, line 376, the expression "However, MSF error generates, significantly" should be corrected, since the verb generate is transitive. It should be expressed like this "However, MSF error arises, significantly".
2. The meaning of "moving speeds" in page 11, line 327 is not clear. It is not stated whether the speed is variable or changes with the experiment.