SERPENTINE ELECTRODE FOR MEMORY DEVICES

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 . 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. The factual inquiries for establishing a background for determining obviousness under 35 U.S.C. 103 are summarized as follows: 1. Determining the scope and contents of the prior art. 2. Ascertaining the differences between the prior art and the claims at issue. 3. Resolving the level of ordinary skill in the pertinent art. 4. Considering objective evidence present in the application indicating obviousness or nonobviousness. Claim(s) 1,3-5,8,9,11,13-15,19,21 is/are rejected under 35 U.S.C. 103 as being unpatentable over Yang et al (PG Pub 2020/0388757 A1) and Liao et al (PG Pub 2021/0257546 A1). Regarding claim 1, Yang teaches a memory device comprising: a first electrically conductive structure (12, figs. 11-13); a metal cap (18D, paragraph [0037]) located on the first electrically conductive structure; a magnetic tunnel junction (MTJ)-containing pillar (28S and 345S, paragraphs [0056][0059]) located above the metal cap; a bottom electrode (24L/26S) having a serpentine pattern (fig. 13) located between the metal cap and the MTJ-containing pillar, wherein the bottom electrode has a bottommost surface that is in contact with the metal cap and a topmost surface in contact with the MTJ-containing pillar. Fig. 13 of Yang does not teach a top electrode located on the MTJ-containing pillar; and a second electrically conductive structure electrically connected to the top electrode. Yang teaches a top electrode forming on the memory device (paragraph [0057]). In the same field of endeavor, Liao teaches a top electrode (127TE, fig. 2C) located on the MTJ-containing pillar (120MTJ); and a second electrically conductive structure (1249VA) electrically connected to the top electrode, for the benefit of providing electrical signals to the MTJ (paragraph [0052]). Thus, it would have been obvious to the skilled in the art before the effective filing date of the invention to include a top electrode located on the MTJ-containing pillar; and a second electrically conductive structure electrically connected to the top electrode, for the benefit of providing electrical signals to the MTJ. Regarding claim 3, Yang teaches the memory device of Claim 1, wherein the MTJ-containing pillar comprises a bottom magnetic material containing layer, a tunnel barrier layer and an upper magnetic material containing layer (paragraph [0059]). Yang does not teach wherein the bottom magnetic material containing layer comprises a magnetic reference material, and the upper magnetic material containing layer comprises a magnetic free material. Liao teaches the bottom magnetic material containing layer comprises a magnetic reference material (pinned 121, figs. 1F and 2C, paragraph [0023]), and the upper magnetic material containing layer comprises a magnetic free material (125, paragraph [0023]), for the benefit of providing a MTJ memory (abstract). Thus, it would have been obvious to the skilled in the art before the effective filing date of the invention to make the bottom magnetic material to contain layer comprises a magnetic reference material, and the upper magnetic material to contain layer comprises a magnetic free material for the benefit of providing a MTJ memory. Regarding claim 4, Yang in view of Liao teaches the memory device of Claim 1, wherein the top electrode and the MTJ-containing pillar are laterally surrounded by an encapsulation liner (30, fig. 13 of Yang; 131, 133, and/or 135 in fig. 2C of Liao). Regarding claim 5, Yang teaches the memory device of Claim 1, further comprising a multi-layered ILD (30/20/16, paragraphs [0052][0023]) containing region located adjacent to, and embedding, the bottom electrode. Regarding claim 8, Yang teaches the memory device of Claim 1, wherein the bottom electrode having the serpentine pattern comprises multiple hills (fig. 13) and valleys (one formed by 24L and another formed by 26S, fig. 13), wherein each hill is in electrical contact with the MTJ-containing pillar, and each valley is in electrical contact with the metal cap (fig. 13). Regarding claim 9, Yang teaches the memory device of Claim 1, wherein the bottom electrode having the serpentine pattern comprises a single hill and a single valley (fig. 13: “comprises” is open-ended, which means other unrecited features can exist), wherein the single hill is in electrical contact with the MTJ-containing pillar, and the single valley is in electrical contact with the metal cap. Regarding claim 11, Yang in view of Liao (see claim 1) teaches a memory device comprising: a first electrically conductive structure; a metal cap located on the first electrically conductive structure; a magnetic tunnel junction (MTJ)-containing pillar located above the metal cap; a multilayered bottom electrode structure (24L and 26S, fig. 13 of Yang) having a serpentine pattern located between the metal cap and the MTJ-containing pillar, wherein multilayered bottom electrode structure has a bottommost bottom electrode in contact with the metal cap and a topmost bottom electrode in contact with the MTJ-containing pillar; a top electrode located on the MTJ-containing pillar; and a second electrically conductive structure electrically connected to the top electrode. Regarding claim 13, Yang in view of Liao (see claim 3) teaches the memory device of Claim 11, wherein the MTJ-containing pillar comprises a bottom magnetic material containing layer, a tunnel barrier layer and an upper magnetic material containing layer, wherein the bottom magnetic material containing layer comprises a magnetic reference material, and the upper magnetic material containing layer comprises a magnetic free material. Regarding claim 14, Yang in view of Liao (see claim 4) teaches the memory device of Claim 11, wherein the top electrode and the MTJ-containing pillar are laterally surrounded by an encapsulation liner. Regarding claim 15, Yang teaches (see claim 5) the memory device of Claim 11, further comprising a multi-layered ILD containing region located adjacent to, and embedding, the multilayered bottom electrode structure. Regarding claim 19, Yang teaches the memory device of Claim 11, wherein the bottommost bottom electrode comprises (fig. 13: “comprises” is open-ended, which means other unrecited features can exist) a single hill and a single valley, wherein the single valley of the bottommost bottom electrode is in electrical contact with the metal cap, and the topmost bottom electrode comprises a single hill and a single valley, wherein the single hill of the topmost bottom electrode is in electrical contact with the MTJ-containing pillar. Regarding claim 21, Yang teaches the memory device of Claim 11, wherein the multilayered bottom electrode structure comprise two bottom electrodes (24L and 26S, fig. 13) that are in intimate contact with each other. Regarding claim 22, Yang teaches the memory device of Claim 21, wherein the two bottom electrodes (Ta 24L, paragraph [0040]; 28 is of different material from 26, paragraph [0046]; 28 is Ta, paragraph [0046], which means 26 is not Ta) are composed of compositionally different conductive metal-containing materials. Claim(s) 2 and 12 is/are rejected under 35 U.S.C. 103 as being unpatentable over Yang et al (PG Pub 2020/0388757 A1) and Liao et al (PG Pub 2021/0257546 A1) as applied to claims 1 and 11 above, and further in view of Houssameddine et al (PG Pub 2022/0130441 A1). Regarding claims 2 and 12, the previous combination remains as applied in claims 1 and 11. Yang further teaches the memory device of Claims 1 and 11, wherein the MTJ-containing pillar comprises a bottom magnetic material containing layer, a tunnel barrier layer and an upper magnetic material containing layer (paragraph [0059]). Yang does not teach wherein the bottom magnetic material containing layer comprises a magnetic free material, and the upper magnetic material containing layer comprises a magnetic reference material. In the same field of endeavor, Houssameddine teaches the bottom magnetic material containing layer comprises a magnetic free material (66L, fig. 9A, paragraph [0071]), and the upper magnetic material containing layer comprises a magnetic reference material (70L, paragraph [0071]), for the benefit of providing a MTJ memory. Thus, it would have been obvious to the skilled in the art before the effective filing date of the invention to make the bottom magnetic material containing layer to comprise a magnetic free material, and the upper magnetic material containing layer to comprise a magnetic reference material, for the benefit of providing a MTJ memory. Claim(s) 10 and 20 is/are rejected under 35 U.S.C. 103 as being unpatentable over Yang et al (PG Pub 2020/0388757 A1) and Liao et al (PG Pub 2021/0257546 A1) as applied to claims 1 and 11 above, and further in view of van der Straten et al (PG Pub 2023/0189535 A1). Regarding claims 10 and 20, the previous combination remains as applied in claims 1 and 11. The previous combination does not teach a diffusion barrier liner located on a sidewall and a bottom surface of the second electrically conductive structure. In the same field of endeavor, van der Straten teaches a diffusion barrier liner (162, fig. 2D) located on a sidewall and a bottom surface of the second electrically conductive structure (165), for the known benefit of providing a conductive layer with reduced electrical resistance (copper 165) while preventing copper diffusion by using barrier 162. Thus, it would have been obvious to the skilled in the art before the effective filing date of the invention to include a diffusion barrier liner located on a sidewall and a bottom surface of the second electrically conductive structure for the known benefit of providing a conductive layer with reduced electrical resistance while preventing copper diffusion. Allowable Subject Matter Claims 6-7 and 16-18 are objected to as being dependent upon a rejected base claim, but would be allowable if rewritten in independent form including all of the limitations of the base claim and any intervening claims. The following is a statement of reasons for the indication of allowable subject matter: Prior art does not teach “a gap filling ILD layer located in each gap created by the serpentine pattern of the bottom electrode” (claims 6 and 16); “the MTJ-containing pillar has a sidewall that is vertically aligned with a sidewall of the top electrode, and the vertically aligned sidewalls of the MTJ-containing pillar and the top electrode extend beyond an outermost sidewall of the bottom electrode” (claims 7 and 17); “the bottommost bottom electrode comprises multiple…valleys,…and the topmost bottom electrode comprises multiple…valleys” (claim 18). Conclusion Any inquiry concerning this communication or earlier communications from the examiner should be directed to FEIFEI YEUNG LOPEZ whose telephone number is (571)270-1882. The examiner can normally be reached M-F: 8am to 4pm EST. 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For additional questions, contact the Electronic Business Center (EBC) at 866-217-9197 (toll-free). If you would like assistance from a USPTO Customer Service Representative, call 800-786-9199 (IN USA OR CANADA) or 571-272-1000. /FEIFEI YEUNG LOPEZ/Primary Examiner, Art Unit 2899