Sidewall Modification Process for Trench Silicon Power Devices

Round 1

Reviewer 1 Report (Previous Reviewer 3)

I have carefully read the revised version of the manuscript and the response to the reviewers' suggestions. The authors have substantially revised the manuscript and answered my comments in a satisfactory way. The manuscript may be accepted.

None

Author Response

Thanks for your suggestion. Extensive English editing work has been done to correct some errors of this paper.

Reviewer 2 Report (Previous Reviewer 2)

Review comments for

Manuscript ID: electronics-2408502-peer-review-v1   

Title: Sidewall modification process for trench silicon power device

Lei Jin, Zhuorui Tang, Long Chen, Guijiu Xie, Zhanglong Chen, Wei Wei, Jianghua Fan, Xiaoliang Gong, Ming Zhang

Submitted to: electronics

Comments:

The revised manuscript persists in serious problems. i) Neither the improved surface uniformity of the Silicon trench sidewall is clear; ii) nor the electrical performance improvement is clear; iii) nor electrical device structure is clear; iv) nor any photodetector device is clearly demonstrated. Moreover, the manuscript is poorly written and very confusing to the readers. The conclusion of the manuscript is not clearly supported by the experimental demonstrations and the manuscript itself has many inaccuracies and ambiguities.

The above issues are clearly mentioned in the original comment, however, these comments are not responded to in the “Response to Reviewer 2 Comments” file.

Hence, the manuscript remains ambiguous and unclear regarding the claimed conclusions and can not be recommended for publication and should be rejected.

Comments for author File: Comments.pdf

Author Response

Please see the attachment

Author Response File: Author Response.pdf

Reviewer 3 Report (New Reviewer)

The manuscript by Jin, et al. reports sidewall modification process for trench Si power device. With etching process tuning and an additional polymer removal step, the wafer-scale fabrication yield is significantly improved. The manuscript is written with appropriate background and motivation. I have several questions and comments, however, about various claims, characterizations, and methodologies in the manuscript that should be addressed. These are listed below in order of my perceived significance:

In Fig 3, the GI thickness shows a noticeable difference between the top and bottom of the trench. The authors attribute this phenomenon primarily to the rough sidewall profile. However, the explanation provided by the authors is not about the relation between GI thickness and the sidewall roughness. It is about the formation of the rough sidewall. From my perspective, the non-uniform GI thickness between top and bottom could be more dominated by the GI deposition condition instead of the etching process. This can be verified by Fig.6 and Fig. 8. With updated etching process, sidewall profile is much smoother in the trench, while the thickness difference between top and bottom remains. I suggest the authors reconsider the causality of the sentence “the major cause of varied thicknesses can be rough sidewall profile by trench etching process”.

In Method, the authors claim that a GI thickness of 600A is deposited. In Fig. 8, however, the GI thickness becomes 450A to 300A. Is this a different GI process compared to what was described in the Method? If yes, please explain the difference and why the process is changed.

There are typos when describing Fig. 7 and Fig. 8(b). Should be 100nA from the figure, not 100mA.

Figure S6 is never mentioned in the manuscript.

Language is acceptable.

Author Response

Please see the attachment

Author Response File: Author Response.pdf

Round 2

Reviewer 2 Report (Previous Reviewer 2)

Review comments for

Manuscript ID: electronics-2154502-peer-review-v2   

Title: Sidewall modification process for trench silicon power devices

Lei Jin, Zhuorui Tang, Long Chen, Guijiu Xie, Zhanglong Chen, Wei Wei, Jianghua Fan, Xiaoliang Gong, Ming Zhang

Submitted to: electronics

Comments:

The authors have modified the manuscript accordingly. The modifications improved the manuscript's quality and readability. I recommend the manuscript for publication.

Comments for author File: Comments.pdf

This manuscript is a resubmission of an earlier submission. The following is a list of the peer review reports and author responses from that submission.

Round 1

Reviewer 1 Report

This work “Sidewall modification process for trench silicon power device” proposes specific fabrication processes to improve profile uniformity and electrical performance of silicon power device and photodetector. The work investigates the effect of trench sidewall modification on the morphology, structure, and electrical properties. This study suggests elimination of trench current leakage issue in large-scale silicon-wafer fabrication.

 

Comments

I believe the technical content of their work is sufficient. The author’s approach in this manuscript is reasonable and well-supported with appropriate explanations. Therefore, I will recommend this manuscript for MDPI Electronics publications.

Comments for author File: Comments.pdf

Author Response

Thanks for your suggesion.

Reviewer 2 Report

Review comments for

Manuscript ID: electronics-2154502-peer-review-v1   

Title: Sidewall modification process for trench silicon power device

Lei Jin, Zhuorui Tang, Long Chen, Guijiu Xie, Zhanglong Chen, Wei Wei, Jianghua Fan, Xiaoliang Gong, Ming Zhang

Submitted to: electronics

Comments:

The submitted manuscript claimed to demonstrate improved surface uniformity of Silicon trench sidewall and consequently demonstrate improvement in the electrical performance of silicon power device and photodetector.

However, the manuscript has serious issues. i) Neither the improved surface uniformity of the Silicon trench sidewall is clear; ii) nor the electrical performance improvement is clear; iii) nor electrical device structure is clear; iv) nor any photodetector device is clearly demonstrated. Moreover, the manuscript is poorly written and very confusing to the readers. The conclusion of the manuscript is not clearly supported by the experimental demonstrations and the manuscript itself has many inaccuracies and ambiguities (listed below). Hence, the manuscript can not be recommended for publication and should be rejected.

1)      There should a space between numerical values and their units. For example, the authors wrote “600A”. It should be “600 A”. This error is present throughout the manuscript. This must be corrected throughout the manuscript.

2)      What is “725um”? This should be “725 µm”. What is “um”? This error is present throughout the manuscript. This must be corrected throughout the manuscript.

3)      Fig. 1: The text label “Hard Mask SiO₂” is not visible in two schematics from the right side. This should be corrected.

4)      Fig. 2a: The text labels and markers should be used on top of the SEM fig. It is confusing to the readers which part is what.

5)      Fig. 2b: What are the different parts of the trench such as “LeftTop”, “LeftRight”, “LeftMiddle”, “Bottom” etc.? These should be marked on top of an SEM image. It is very confusing and can not be understood currently.

6)      A clear device structure of the transistor (MOSFET) is missing in the manuscript. Where are the source, drain, and gate electrodes? Where is the channel? This should be clearly marked on top of an SEM or schematic diagram. Currently, this is unacceptable.

7)      Fig. 3: What is the current (Y-axis of the plot)? Is it gate-to-source current (I_GS) or drain-to-source current (I_DS)? This should be clearly written. It's very confusing now.

8)      Fig. 3: What is the voltage (X-axis of the plot)? Is it gate-to-source voltage (V_GS) or drain-to-source voltage (V_DS)? This should be clearly written. It's very confusing now.

9)      Fig. 4: What is Vth curve? From which reference authors took this terminology “Vth curve”. Either should clearly define this new terminology in their manuscript with proper descriptions or details or refer to the appropriate references from where they adopted this terminology. The proper terminology should be transfer characteristics (I_DS-V_GS curve) or Output characteristics (I_DS-V_DS curve) in which threshold voltage (V_th) should be marked. The current description is wrong.

10)  Page 1, line 17: The authors mentioned “In this study, trench sidewall modification processes are conducted  to  improve  profile  uniformity and electrical performance of silicon power device and photodetector”.  Where is the photodetector demonstrated in this manuscript?

Comments for author File: Comments.pdf

Reviewer 3 Report

Comments are attached. 

Comments for author File: Comments.pdf