Effect of Temperature on the Chip Soldering Process with AuGa0.03 Alloy Solder

Round 1

Reviewer 1 Report

1. There are a lot of VERY LONG sentences. For example (Lines 14-19), “With the welding temperature increasing gradually, the X-ray photos of the samples for the chip welding, the outcome of the diffraction of XRD for the joint, the photos reflecting the microstructure of joints under the SEM, and the EDS to the cross section of the chip soldering samples, it can be seen that the phase composition is not affected by the change of the welding temperature and all the joint structures are the Au+Si eutectic structure, while the Au-Si eutectic reaction occurred during the welding process.”. Due to this fact, the manuscript is very difficult to understand. They should be divided into several sentences through all text, and English should be improved in general. 2. Welding and soldering are not the same processes (as well as brazing). The standard terms should be used through the manuscript. The same problem with “Eutectic welding”, “holes”, and other used terms. See, for example, ANSI-AWS A3.0-2001 “Stantard Welding Terms and Definitions”; ISO 4063 “Welding and allied processes — Nomenclature of processes and reference numbers”, ISO 857-1 “Welding and allied processes — Vocabulary — Part 1: Metal welding processes”, ISO 857-2 “Welding and allied processes — Vocabulary — Part 1: Soldering and brazing processes and related terms”. 3. Spaces are missing in some places. For example, Line 40 “solder[15,16]is”, Line 42 “solder[17]is”, etc. 4. There is no information how material temperature was measured in the “Experimental” section. 5. Quality of Figure 1 and 2 is too low. It is not clear what are shown. 6. There is no agreement on the used tenses (present/past, simple/perfect). Therefore it is not clear what has happened during the experiment, and what is the result or discussion. Also, please divide the “Results&Discussion” section into two separate ones (“Results” and “Discussion”). 7. There are several description of the same “EDS”, “XRD” terms in different sections. 8. In accordance with the subject of the manuscript, a phase diagram should be given and conclusions drawn based on it.

Author Response

Dear reviewer,

   Thank you for your review. Here is my revision of the paper。

   1.There are a lot of VERY LONG sentences. For example (Lines 14-19), “With the welding temperature increasing gradually, the X-ray photos of the samples for the chip welding, the outcome of the diffraction of XRD for the joint, the photos reflecting the microstructure of joints under the SEM, and the EDS to the cross section of the chip soldering samples, it can be seen that the phase composition is not affected by the change of the welding temperature and all the joint structures are the Au+Si eutectic structure, while the Au-Si eutectic reaction occurred during the welding process.”. Due to this fact, the manuscript is very difficult to understand. They should be divided into several sentences through all text, and English should be improved in general.

      According to your Suggestions, we have revised many obscure English points in the text, and asked professional English professionals for guidance. If it is not clear, please feel free to give your comments. Thank you very much!

   2.Welding and soldering are not the same processes (as well as brazing). The standard terms should be used through the manuscript. The same problem with “Eutectic welding”, “holes”, and other used terms. See, for example, ANSI-AWS A3.0-2001 “Stantard Welding Terms and Definitions”; ISO 4063 “Welding and allied processes — Nomenclature of processes and reference numbers”, ISO 857-1 “Welding and allied processes — Vocabulary — Part 1: Metal welding processes”, ISO 857-2 “Welding and allied processes — Vocabulary — Part 1: Soldering and brazing processes and related terms”.

   According to the related standard, we chose the soldering instead of wedding.

Spaces are missing in some places. For example, Line 40 “solder[15,16]is”, Line 42 “solder[17]is”, etc.

     This problem has been modified in the article.

    4.There is no information how material temperature was measured in the “Experimental” section

    We added a picture of the experimental equipment shown in figure 1, and introduced how to measure the temperature in lines 73 to 78.The platinum-rhodium thermocouple with high stability was used to measure the temperature of the heating surface,and then the temperature was controlled by deep-cavity eutectic soldering table.

    5.Quality of Figure 1 and 2 is too low. It is not clear what are shown.

   Figure 1 and Figure 2 have been replaced with HD pictures, and the leader and scale have been awarded in the figure.

    6.There is no agreement on the used tenses (present/past, simple/perfect). Therefore it is not clear what has happened during the experiment, and what is the result or discussion. Also, please divide the “Results&Discussion” section into two separate ones (“Results” and “Discussion”).

     According to your opinion, the results and discussion section is divided into two separate sections.The past style is used in the experimental part, and the modern style is used in the discussion part.

    7. There are several description of the same “EDS”, “XRD” terms in different sections.

   Lines 60 and 70 explain EDS and XRD, and the rest are changed to abbreviations.

     8.In accordance with the subject of the manuscript, a phase diagram should be given and conclusions drawn based on it.

    According to your opinion, I have added a phase diagram as shown in figure 4 and analyzed the conclusion according to the phase diagram in lines 136 to 141.

     Thank you in advance for your kind cooperation and we look forward to hearing from you soon.

Author Response File: Author Response.docx

Reviewer 2 Report

The paper is interesting and fits the scope of the journal. However, it can be improved following these comments and suggestions.

English should be revised to improve clarity of the manuscript.

Examples of eutectic welding should be described in more detail in the introduction. See some examples such as: 10.1016/j.actamat.2015.12.021, 10.1007/s00170-018-1633-6 and 10.1016/j.pmatsci.2017.04.008.

Can the authors provide a photo of the welding setup with the material included?

Figure 1 needs a scale. Some arrows pointing to specific features in figure 1 should also be added.

Figure 2 needs bigger scale. Why c and e have so many points in the cross section? Is this an image error or something similar?

In figure 4 c is that a pore? If yes how was it formed? How to avoid it? Can the chips be used with such defects? This should be mentioned in the manuscript.

Where are the mechanical properties of the joints? This should be added. The fracture surfaces should also be presented and analysed to understand the impact of welding on the mechanical behaviour.

Author Response

Dear reviewer,

   Thank you for your review. Here is my revision of the paper.

1.English should be revised to improve clarity of the manuscript.

According to your Suggestions, we have revised many obscure English points in the text, and asked professional English professionals for guidance. If it is not clear, please feel free to give your comments. Thank you very much!

2.Examples of eutectic welding should be described in more detail in the introduction. See some examples such as: 10.1016/j.actamat.2015.12.021, 10.1007/s00170-018-1633-6 and 10.1016/j.pmatsci.2017.04.008.

According to your Suggestions,we also cite three articles describing eutectic welding examples, as shown in lines 41 to 43.

3.Can the authors provide a photo of the welding setup with the material included?

We added a picture of the experimental equipment shown in figure 1,Lines 73 to 78 give a brief description of its functions.

4.Figure 1 needs a scale. Some arrows pointing to specific features in figure 1 should also be added.

Figure 1 has been replaced with HD pictures, and the leader and scale have been awarded in the figure.

5.Figure 2 needs bigger scale. Why c and e have so many points in the cross section? Is this an image error or something similar?

Figure 2 has been replaced with HD pictures, and the leader and scale have been awarded in the figure. The points in the cross section is an image error,we have replaced the pictures with HD pictures.

6.In figure 4 c is that a pore? If yes how was it formed? How to avoid it? Can the chips be used with such defects? This should be mentioned in the manuscript.

Here is a pore, mainly due to the low welding temperature, which has not reached the process temperature. This kind of defect is not allowed in the process..A brief introduction is added to lines 175 to 178.

7.Where are the mechanical properties of the joints? This should be added. The fracture surfaces should also be presented and analysed to understand the impact of welding on the mechanical behaviou

According to your opinion, I have added Table 1 to explain the corresponding shear strength of the corresponding chip at different temperatures. analyzed the conclusion according to the Table 1 in lines 216 to 225.

    Thank you in advance for your kind cooperation and we look forward to hearing from you soon.

Author Response File: Author Response.docx

Round 2

Reviewer 1 Report

A mix of past and present tenses, double spaces and no spaces, capital letters as well as articles and other grammar mistakes should be checked through the text. Lines 14-18 Too long sentences have not been divided, for example: “The X-ray imagesof chip soldering samples, the XRD diffraction analysis of the joints, the SEM images reflecting the microstructures of the joints, and the EDS of the cross-sections of the chip soldering samplesshow that with gradually increasing soldering temperature, the phase composition is not affected,and all the joint structures are the Au+Si eutectic structure;the Au-Si eutectic reaction occurs during the soldering process.” Line 31 and 139, and further What means the terms “Eutectic soldering” and “holes”? Please refer the standard or write correctly. Line 34-37 Why the authors have referred dissimilar welding if the manuscript is devoted to soldering? Why present simple tense has been used in the “ Experimental” section? Line 52 How the phrase “For the welded encapsulation” is connected with soldering? The “ Experimental” section. Please describe equipment and test conditions is details. Line 63-68 The description of the “a domestic deep-cavity eutectic soldering table” should move in the “ Experimental” section. Please check “igure 2” The “Results” and section is. Figure 2 Please describe the arrows. The promised state diagram and revised conclusions have not been found.

Author Response

Dear Reviewer，

    Thank you for your review, here are the changes I have made based on your review comments.

   1.A mix of past and present tenses, double spaces and no spaces, capital letters as well as articles and other grammar mistakes should be checked through the text.

    According to your review opinions, we have revised many defects in the manuscript as follows.The tense has been modified, for example, the experimental part has been changed to the past tense;The double Spaces are modified on lines 2, 34, 61, 66, 74, 84, 161, 174, 259, etc；Lines 217, 219，etc.have been modified without Spaces；Line 38 adds”because of”; Line 243 “to” is changed to” for”;  Line 45 “during” is changed to “over”； Line 177 “there in” is changed to “therein”; and so on.

  2.Lines 14-18 Too long sentences have not been divided, for example: “The X-ray imagesof chip soldering samples, the XRD diffraction analysis of the joints, the SEM images reflecting the microstructures of the joints, and the EDS of the cross-sections of the chip soldering samplesshow that with gradually increasing soldering temperature, the phase composition is not affected,and all the joint structures are the Au+Si eutectic structure; the Au-Si eutectic reaction occurs during the soldering process.”

  The long sentence you mentioned in the manuscript has been changed into two short sentences.

  3.Line 31 and 139, and further What means the terms “Eutectic soldering” and “holes”? Please refer the standard or write correctly.

  (1)Eutectic soldering, also called eutectic bonding, is where the combination of two or more metals allow direct transformation from solid to liquid state or vice versa at specific temperature without passing two-phase equilibrium. The eutectic temperature is much lower than the melting temperature of the materials that are involved in the bonding process.

   (2)In this paper, “hole ” is changed to”pore”.

  4.Line 34-37 Why the authors have referred dissimilar welding if the manuscript is devoted to soldering?

  This part focuses on the statement that adding different alloys improves the welding or soldering performance, which is suggested by another reviewer.

  5.Why present simple tense has been used in the “ Experimental” section?

     The experimental part has been changed to the past formula.

   6.Line 52 How the phrase “For the welded encapsulation” is connected with soldering?

   We deleted the phrase "For the welded encapsulation",and this sentence has been changed to”The customized deep cavity eutectic soldering station is utilized to encapsulate chips,…”.

  7.The “ Experimental” section. Please describe equipment and test conditions is details.

  Lines 63-68 have been moved to the experimental section.And the models of instrument used to collect data or pictures have been added in the experiment section,See lines 67 to 74.

    8.Line 63-68 The description of the “a domestic deep-cavity eutectic soldering table” should move in the “ Experimental” section.

  Lines 63-68 have been moved to the experimental section.

  9.Please check “Figure 2” The “Results” and section is. Figure 2 Please describe the arrows. The promised state diagram and revised conclusions have not been found. 

   According to your review opinions, we have added a section to explain what the arrows represent in Figure 2, and we have drawn conclusions from the five figures;see lines 90 to 98.

    Do not hesitate to contact us if you have any questions about the manuscript . We look forward to hearing from you soon.Thank you.                    

Author Response File: Author Response.docx

Reviewer 2 Report

Manuscript was greatly improved.

Author Response

Dear Reviewer,

    Thank you for your review.The first round has passed, so I have no reply.