DETAILED ACTION
This action is responsive to the application No. 18/450,731 filed on August 16, 2023.
Notice of Pre-AIA or AIA Status
The present application, filed on or after March 16, 2013, is being examined under the first inventor to file provisions of the AIA .
Election/Restrictions
Applicant’s election with traverse of the Group I invention and Species 2 reading on Fig. 20 in the reply filed on 01/08/2026 is acknowledged. The Applicants indicated that claims 1-9 read on the elected species. However, claims 3 and 5 read on non-elected species of the claimed invention. For instance, claim 3 recites that: “the first portion and the second portion are made of a same material, and are specifically made of doped polysilicon”, a feature that is exclusive of Species 1 depicted in Fig. 16. Claim 5 recites limitations exclusive of Species 3 depicted in Fig. 24. Claims 3, 5, and 10-18 are withdrawn from further consideration pursuant to 37 CFR 1.142(b) as being drawn to nonelected invention/species, there being no allowable generic or linking claim. Accordingly, pending in this Office action are claims 1-18.
The traversal is on the grounds that the Office has failed to articulate facts sufficient to demonstrate that the asserted groups and species are distinct and lack the same or corresponding special technical feature.
This is found not persuasive because the inventions have acquired a separate status in the art in view of their different classification, for instance, the device claims classified in CPC class H10B 12/34 related to transistors being at least partially in a trench in the substrate, and the method claims, classified in CPC class H01L 21/00 related to exclusively concerning details of the manufacture or treatment of semiconductor or solid state devices or of parts thereof.
Further, according to the applicants, there are claims reciting limitations of species 1-3 that depend from generic claims, therefore, species 1-3 are mutually related and the search field for all species is similar. The argument about claims reading on species 1-3 depending from the same generic claims is not evidence that the species are not mutually exclusive. The examiner can require a restriction in applications where generic claims recite features that are common to a multiplicity of species. In the previous restriction on page 4, the examiner set forth that the application contained three species, each including mutually exclusive characteristics. For instance, layer 34 of Species 1 is a single continuous layer made of a single material, whereas layer 34 of Species 2 comprises two different layers made of different materials and layer 34 of Species 3 comprises three different layers made of different materials. These exclusive characteristics make the species patentably distinct from each other. That is, the unpatentability of one of the species would not necessarily imply the unpatentability of the other species. The applicants, on the other hand, have failed to advance reasons leading to the conclusion that the species claimed are considered clearly unpatentable over each other. Accordingly, the prior art applicable to one of the species would not likely be applicable to the other species as the species are likely to raise different prior art issues. Since each of the species belongs to a different subject of inventive effort, they will require different fields of search (e.g., employing different search queries) that would allow separately searching for each of their mutually exclusive characteristics, thus creating a serious burden on the examiner.
For all the above reasons, the requirement is still deemed proper and is, therefore, made FINAL.
Specification
The title of the invention is not descriptive. A new title is required that is clearly indicative of the invention to which the claims are directed.
Claim Rejections - 35 USC § 102
In the event the determination of the status of the application as subject to AIA 35 U.S.C. 102 and 103 (or as subject to pre-AIA 35 U.S.C. 102 and 103) is incorrect, any correction of the statutory basis (i.e., changing from AIA to pre-AIA ) for the rejection will not be considered a new ground of rejection if the prior art relied upon, and the rationale supporting the rejection, would be the same under either status.
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)(2) the claimed invention was described in a patent issued under section 151, or in an application for patent published or deemed published under section 122(b), in which the patent or application, as the case may be, names another inventor and was effectively filed before the effective filing date of the claimed invention.
Claims 1, 2, 7, and 9 are rejected under 35 U.S.C. 102(a)(2) as being anticipated by Lee (US 2023/0178439).
Regarding Claim 1, Lee (see, e.g., Fig. 7), teaches a semiconductor structure SDc, comprising a substrate SB and a word line (WL) structure G1d/G2 located in a WL trench T (see, e.g., pars. 0024, 0047), wherein the WL structure G1d/G2 comprises:
a work function stacking structure G1d located in the substrate SB, wherein an upper surface of the work function stacking structure G1d is lower than a top face of the WL trench T, the work function stacking structure G1d comprises a plurality of sequentially and alternately stacked first work function layers GL2a and second work function layers GL1a, and a work function of the first work function layer GL2a is greater than a work function of the second work function layer GL1a (WFMo (4.6 – 4.95 eV) > WFTa (4.25 – 4.5 eV) (see, e.g., par. 0048);
a WL conductive layer G2/GL1b located in the substrate SB, and located on an upper surface of the work function stacking structure G1d (see, e.g., pars. 0024, 0042); and
a gate oxide layer GD located between the work function stacking structure G1d and the substrate SB as well as between the WL conductive layer G2/GL1b and the substrate SB (see, e.g., par. 0024).
Regarding Claim 2, Lee teaches all aspects of claim 1. Lee (see, e.g., Fig. 7), teaches that the WL conductive layer G2/GL1b comprises a first portion GL1b and a second portion G2, the first portion GL1b is located under the second portion G2, the work function stacking structure G1d has a "U" shaped cross-section and the work function stacking structure G1d surrounds a sidewall and a bottom face of the first portion GL1b, and the second portion G2 covers a top face of the first portion GL1b and a top face of the work function stacking structure G1d.
Regarding Claim 7, Lee teaches all aspects of claim 1. Lee (see, e.g., Fig. 6), teaches that:
the WL trench T is formed in the substrate SB;
the gate oxide layer GD covers a sidewall and a bottom of the WL trench T;
the first work function layer GL2a is located on a surface of the gate oxide layer GD; and
the WL conductive layer G2/GL1b is located in the WL trench T, and an upper surface of the WL conductive layer G2/GL1b is lower than a top of the WL trench T.
Regarding Claim 9, Lee teaches all aspects of claim 7. Lee (see, e.g., Fig. 6), teaches, wherein the WL structure G1d/G2 further comprises an insulating isolation layer GC located on the upper surface of the WL conductive layer G2/GL1b and filling up the WL trench T (see, e.g., pars. 0024, 0033).
Claim Rejections - 35 USC § 103
In the event the determination of the status of the application as subject to AIA 35 U.S.C. 102 and 103 (or as subject to pre-AIA 35 U.S.C. 102 and 103) is incorrect, any correction of the statutory basis for the rejection will not be considered a new ground of rejection if the prior art relied upon, and the rationale supporting the rejection, would be the same under either status.
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 4 is rejected under 35 U.S.C. 103 as being unpatentable over Lee (US 2023/0178439) in view of Kim (US 2024/0064964).
Regarding Claim 4, Lee teaches all aspects of claim 2. Lee (see, e.g., Fig. 6), teaches that the first portion GL1b and the second portion G2 are made of different materials, the first portion comprises a tantalum layer, and the second portion G2 comprises a doped polysilicon layer (see, e.g., pars. 0032, 0042).
Lee discloses the claimed invention except for the use of tantalum instead of titanium nitride for the first portion. Kim (see, e.g., Fig. 4, par. 0054), on the other hand teaches that titanium nitride and tantalum are equivalent materials known in the art. Therefore, because these gate electrode materials were art-recognized equivalents at the time of the invention, one skilled in the art could have combined the elements as claimed by known methods with no change in their respective functions, one of ordinary skill in the art would have found it obvious to substitute titanium nitride for tantalum since the substitution would yield predictable results. See Supreme Court decision in KSR International Co. v. Teleflex Inc., 550 U.S. _, 82 YSPQ2d 1385 (2007).
Claim 6 is rejected under 35 U.S.C. 103 as being unpatentable over Lee (US 2023/0178439) in view of Jeonil Lee (US 2023/0178634).
Regarding Claim 6, Lee teaches all aspects of claim 1. Lee (see, e.g., Fig. 6), teaches that the first work function layer GL2a comprises a molybdenum layer, and the second work function layer GL1a comprises at least one of a titanium layer, a tantalum layer, or a tantalum nitride layer (see, e.g., par. 0042).
Lee is silent with respect to the claim limitation that the first work function layer GL2a comprises a titanium nitride layer.
Lee discloses the claimed invention except for the use of molybdenum instead of titanium nitride for the first portion. Jeonil Lee (see, e.g., Fig. 1, par. 0039), on the other hand teaches that titanium nitride and molybdenum are equivalent materials known in the art. Therefore, because these work function materials were art-recognized equivalents at the time of the invention, one skilled in the art could have combined the elements as claimed by known methods with no change in their respective functions, one of ordinary skill in the art would have found it obvious to substitute titanium nitride for molybdenum since the substitution would yield predictable results. See Supreme Court decision in KSR International Co. v. Teleflex Inc., 550 U.S. _, 82 YSPQ2d 1385 (2007).
Claim 8 is rejected under 35 U.S.C. 103 as being unpatentable over Lee (US 2023/0178439) in view of Mittal (US 6,099,939)
Regarding Claim 8, Lee teaches all aspects of claim 7. Lee is silent with respect to the claim limitation that the surface of the gate oxide layer in the WL trench is a rough surface.
Mittal, on the other hand, teaches enhancing the adhesion between a metal and a dielectric polymer comprising surface roughness (see, e.g., col. 4, ll. 47-51).
It would have been obvious to one of ordinary skill in the art at the time of filing to have in Lee’s device, the surface of the gate oxide layer in the WL trench being a rough surface, as taught by Mittal, to enhance the adhesion between a metal and a dielectric.
Conclusion
Any inquiry concerning this communication or earlier communications from the examiner should be directed to Nelson Garcés whose telephone number is (571)272-8249. The examiner can normally be reached on M-F 9:00 AM - 5:30 PM.
If attempts to reach the examiner by telephone are unsuccessful, the examiner’s supervisor, Wael Fahmy can be reached on (571)272-1705. The fax phone number for the organization where this application or proceeding is assigned is 571-273-8300. Information regarding the status of an application may be obtained from the Patent Application Information Retrieval (PAIR) system. Status information for published applications may be obtained from either Private PAIR or Public PAIR. Status information for unpublished applications is available through Private PAIR only. For more information about the PAIR system, see http://pair-direct.uspto.gov. Should you have questions on access to the Private PAIR system, contact the Electronic Business Center (EBC) at 866-217-9197 (toll-free). If you would like assistance from a USPTO Customer Service Representative or access to the automated information system, call 800-786-9199 (IN USA OR CANADA) or 571-272-1000.
/Nelson Garces/
Primary Examiner, Art Unit 2814