DETAILED ACTION
This office action is in response to Application No. 18/422,319, filed on 25 January 2024. Claims 1-20 are pending.
The present application, filed on or after March 16, 2013, is being examined under the first inventor to file provisions of the AIA .
Claim Rejections - 35 USC § 102
The following is a quotation of the appropriate paragraphs of 35 U.S.C. 102 that form the basis for the rejections under this section made in this Office action:
A person shall be entitled to a patent unless –
(a)(1) the claimed invention was patented, described in a printed publication, or in public use, on sale, or otherwise available to the public before the effective filing date of the claimed invention.
Claim(s) 1-6, 10-13, and 16-18 is/are rejected under 35 U.S.C. 102(a)(1) as being anticipated by Tetelbaum (US 2012/0284679).
Regarding claim 1, Tetelbaum discloses a method comprising: accessing physical design data for an integrated circuit (IC) layout, wherein the physical design data comprises a netlist comprising active metal shapes of a metal shapes infrastructure forming signal path nets connecting different parts of the IC layout (¶¶18, 19); performing timing-based design rule checking of the physical design data to identify net timing characteristics of the signal path nets and net timing properties of the active metal shapes of the metal shapes infrastructure (Fig. 4, critical signal wire 410; ¶¶12-14, 20, 21); and performing shape-based density design rule checking of the metal shapes infrastructure, based on the net timing characteristics and the net timing properties of the active metal shapes, to perform fill insertion of metal fill shapes to satisfy density requirements in the IC layout (¶¶21, 22).
Regarding claim 2, Tetelbaum discloses that the physical design data further comprises metal fill shapes of the metal shapes infrastructure, and wherein performing timing-based design rule checking of the physical design data further comprises performing timing-based design rule checking of the active metal shapes forming the signal path nets and the metal fill shapes of the metal shapes infrastructure to identify the net timing characteristics of the signal path nets and the net timing properties of the active metal shapes of the metal shapes infrastructure, and to identify metal fill shapes insertion to minimize timing delay to signal paths, and to increase timing delay to signal paths (¶¶27, 28, 32).
Regarding claim 3, Tetelbaum discloses that performing shape-based density design rule checking of the metal shapes infrastructure further comprises assigning net timing priorities of the active metal shapes forming the signal path nets into the metal shapes infrastructure based on the net timing characteristics of the signal path nets and the net timing properties of the active metal shapes (Fig. 4, critical signal wire 410; ¶¶12-14, 20, 32).
Regarding claim 4, Tetelbaum discloses that the physical design data further comprises metal fill shapes of the metal shapes infrastructure, and wherein performing shape-based density design rule checking of the metal shapes infrastructure includes performing shape-based density design rule checking of the active metal shapes forming the signal path nets and the metal fill shapes (¶22).
Regarding claim 5, Tetelbaum discloses that performing shape-based density design rule checking of the metal shapes infrastructure further comprises performing the fill insertion of metal fill shapes to achieve a predefined minimum density threshold to satisfy density requirements in the IC layout (¶22).
Regarding claim 6, Tetelbaum discloses that performing shape-based density design rule checking of the metal shapes infrastructure further comprises identifying critical signal path nets based on the net timing characteristics of the signal path nets, and performing shape-based density design rule checking of the critical signal path nets first (¶¶12, 14, 20, 21).
Regarding claim 10, Tetelbaum discloses that performing shape-based density design rule checking of the physical design data further comprises identifying a potential timing impact for each added metal fill shape to build a dynamic approximation of timing impact for the fill insertion of the metal fill shapes (¶¶27, 28).
Claims 11-13 are directed to systems comprising one or more processors and memory for performing the methods of claims 1, 3, and 6, and are rejected under the same reasoning. Tetelbaum discloses systems comprising one or more processors and memory for performing the claimed methods (¶5).
Claims 16-18 are directed to computer program products for performing the methods of claims 1, 3, and 6, and are rejected under the same reasoning. Tetelbaum discloses computer program products for performing the claimed methods (¶5).
Claim Rejections - 35 USC § 103
The following is a quotation of 35 U.S.C. 103 which forms the basis for all obviousness rejections set forth in this Office action:
A patent for a claimed invention may not be obtained, notwithstanding that the claimed invention is not identically disclosed as set forth in section 102, if the differences between the claimed invention and the prior art are such that the claimed invention as a whole would have been obvious before the effective filing date of the claimed invention to a person having ordinary skill in the art to which the claimed invention pertains. Patentability shall not be negated by the manner in which the invention was made.
Claim(s) 7, 14, and 19 is/are rejected under 35 U.S.C. 103 as being unpatentable over Tetelbaum in view of Oh (US 6,904,581).
Regarding claims 7, 14, and 19, Tetelbaum discloses that performing shape-based density design rule checking of the critical signal path nets first further comprises assigning 3-dimensional track spacings based on timing slack thresholds of the critical signal path nets, and performing the fill insertion of metal fill shapes based on the timing slack thresholds of respective critical signal path nets to achieve a predefined minimum density threshold to satisfy density requirements in the IC layout (¶¶13, 21, 22, 27, 28). If Tetelbaum is found to be unclear regarding 3D spacings, Oh discloses the same (Figs. 1 and 2 and related text). It would have been obvious to persons having ordinary skill in the art before the effective filing date of the application to combine the teachings of Tetelbaum and Oh, because doing so would have involved merely the routine combination of known elements according to known techniques, or the routine use of a known technique to improve similar devices in the same way, to produce merely the predictable results of avoiding fill insertion on other layers that would cause timing violations. KSR Int’l Co. v. Teleflex Inc., 82 U.S.P.Q.2d 1385, 1395-1396. Tetelbaum discloses excluding fill from any spacing around critical nets that would cause a timing violation. Persons having ordinary skill in the art reading Tetelbaum would recognize that this would be a 3D spacing, since fill on other layers could cause timing violations, and Oh provides explicit evidence of the 3D spacing. The teachings of Oh are directly applicable to Tetelbaum in the same way, so that Tetelbaum would similarly use 3D spacings around critical nets to avoid fill insertion on other layers that would cause timing violations.
Claim(s) 8, 15, and 20 is/are rejected under 35 U.S.C. 103 as being unpatentable over Tetelbaum in view of Noice (US 8,161,425).
Regarding claims 8, 15, and 20, Tetelbaum discloses that performing shape-based density design rule checking of the metal shapes infrastructure further comprises identifying non-critical signal path nets based on the net timing characteristics of the signal path nets (¶¶12, 14, 20), but does not appear to explicitly disclose performing shape-based density design rule checking of the non-critical signal path nets first. Noice discloses performing shape-based density design rule checking of the non-critical signal path nets first (col. 6, lines 32-41; col. 10, lines 11-16).
It would have been obvious to persons having ordinary skill in the art before the effective filing date of the application to combine the teachings of Tetelbaum in view of Noice, because doing so would have involved merely the routine combination of known elements according to known techniques, or the routine use of a known technique to improve similar devices in the same way, to produce merely the predictable results of minimizing the timing impact of metal fill required to meet density requirements. KSR Int’l Co. v. Teleflex Inc., 82 U.S.P.Q.2d 1385, 1395-1396. Tetelbaum discloses a metal fill insertion process based on timing criticality. Noice teaches that metal fill insertion should be performed around non-critical nets first to minimize timing impact. The teachings of Noice are directly applicable to Tetelbaum in the same way, so that Tetelbaum would similarly insert metal fill around non-critical nets first to minimize timing impact.
Claim(s) 9 is/are rejected under 35 U.S.C. 103 as being unpatentable over Tetelbaum in view of Noice and Surprise (US 10,943,051).
Regarding claim 9, Tetelbaum discloses that performing shape-based density design rule checking of the non-critical signal path nets first further comprises adding metal fill shapes based on the timing slack thresholds of respective non-critical signal nets to achieve a predefined minimum density threshold to satisfy density requirements in the IC layout (¶¶22, 28), but does not appear to explicitly disclose assigning 3-dimensional fill zones based on timing slack thresholds of the non-critical signal path nets, and adding metal fill shapes in the 3-dimensional fill zones. Noice discloses assigning 3-dimensional fill zones based on timing slack thresholds of the non-critical signal path nets, and adding metal fill shapes in the 3-dimensional fill zones based on the timing slack thresholds of respective non-critical signal path nets (Figs. 5, 6, and 7B: metal fill shapes in nearby layers; col. 5, lines 36-42; col. 9, lines 1-8). If Noice is found to be unclear regarding these limitations, Surprise also discloses the same (Figs. 1A-1C; col. 9, line 26 to col. 10, line 15).
It would have been obvious to persons having ordinary skill in the art before the effective filing date of the application to combine the teachings of Tetelbaum, Noice, and Surprise, because doing so would have involved merely the routine combination of known elements according to known techniques, or the routine use of a known technique to improve similar devices in the same way, to produce merely the predictable results of avoiding timing violations from metal fill. KSR Int’l Co. v. Teleflex Inc., 82 U.S.P.Q.2d 1385, 1395-1396. Tetelbaum discloses metal fill insertion based on timing slack. Noice teaches that timing impacts from fill are both intra- and inter-layer (i.e. 3D), and that fill candidates are inserted in order of timing cost, which is based on slack. Surprise provides more explicit teaching of both 3D fill and fill insertion that avoids slack impact beyond thresholds. The teachings of Noice and Surprise are directly applicable to Tetelbaum in the same way, so that Tetelbaum would similarly perform 3D fill insertion in consideration of slack, to avoid causing new timing violations from intra- or inter-layer fill.
Conclusion
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26 August 2026
/ARIC LIN/ Examiner, Art Unit 2851
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