Timing Criticality-Aware Design Optimization Using BEOL Air Gap Technology on Consecutive Metal Layers

Round 1

Reviewer 1 Report

In this report an analytical method for estimating the performance gain by applying an AG and a physical design methodology for maximizing the performance with minimum cost is reported.

This manuscript is an interesting paper, clearly written and addressing a top subject.

Author Response

Dear Editor and Reviewers,

 

We greatly appreciate your efforts and valuable comments on our manuscript. All comments by the reviewer have been addressed, with corresponding changes made directly to the manuscript where appropriate.

Sincerely,

 

Author Response File: Author Response.pdf

Reviewer 2 Report

Dear authors and editor,

I have carefully read and examined the manuscript entitled “Timing Criticality-Aware Design Optimization using BEOL Air Gap Technology on Consecutive Metal Layers” authored by Seongmin Ryu et al.

The manuscript details the design methodology for using airgaps with minimal cost and maximum efficiency gain. Furthermore an analytical approach to estimate the performance gain is presented together with an optimal set of metal-layer combinations. In a following part an AG-aware physical design methodology for maximizing the performance with minimum cost is developed. Finally, different process challenges and the yield are discussed.

It is my opinion that the overall quality of the paper is very high. Both the text and graphical presentation is clear and well designed. Furthermore, the paper is very well structured and the results are presented in a well-organized manner.

The only real comment I have, is that sometimes the text is somewhat inaccessible for outsiders. For example, in the abstract a few sentences that do not contain jargon and give the proper context would be of interest to many readers. Furthermore, some context to why this performance gain of a few percent is so appealing would be advisable to inform the novice reader.

I have a few minor purely esthetic comments about the figures:

Fig. 6(d): if possible add some numbers to the axis.

Fig. 8(c): if possible re-layout the figure to show numbers on the axis (0, 0.5, 1)

Fig. 9(c): the numbers on the axis are somewhat small. Is it possible to improve the clarity? Maybe larger font/less numbers?

Fig. 10(b): please add values to the x-axis.

Fig. 12(b): is it possible to enlarge this figure or make it sharper? And maybe indicate size/components?

It would improve the readability if all plots had the same layout and font size for the axis labels and values.

Kind regards,

The reviewer

Author Response

Dear Editor and Reviewers,

 

We greatly appreciate your efforts and valuable comments on our manuscript. All comments by the reviewer have been addressed, with corresponding changes made directly to the manuscript where appropriate.

 

<For Reviewer 2>

 

Comment 1: The only real comment I have, is that sometimes the text is somewhat inaccessible for outsiders. For example, in the abstract a few sentences that do not contain jargon and give the proper context would be of interest to many readers. Furthermore, some context to why this performance gain of a few percent is so appealing would be advisable to inform the novice reader.

 

Response: According to the reviewer’s opinion, we removed ambiguous part in the second sentence in the abstract as follows,

However, the “blind” use of AG based on traditional design methodologies does not provide sufficient performance gain and presents multiple challenges during manufacturing.

And, we added a sentence to the abstract to show the implications of the performance improvement from our work as follows,

The performance gain achieved represents about half of the 10-15% performance improvement under the same power by a process node shrink.

 

Comment 2: I have a few minor purely esthetic comments about the figures:

Fig. 6(d): if possible add some numbers to the axis.

Fig. 8(c): if possible re-layout the figure to show numbers on the axis (0, 0.5, 1)

Fig. 9(c): the numbers on the axis are somewhat small. Is it possible to improve the clarity? Maybe larger font/less numbers?

Fig. 10(b): please add values to the x-axis.

Fig. 12(b): is it possible to enlarge this figure or make it sharper? And maybe indicate size/components?

 

Response: We modified the figure as follows,

Fig. 6(d): We added values to the x and y-axis.

Fig. 8(c): We added values to the x and y-axis.

Fig. 9(c): We enlarged the font size and reduced the numbers on the axis for clarity.

Fig. 10(b): We added values to the x-axis.

Fig. 12(b): We enlarged the figure.

 

 

Sincerely,

Author Response File: Author Response.pdf