DETAILED ACTION
Continued Examination Under 37 CFR 1.114
A request for continued examination under 37 CFR 1.114, including the fee set forth in 37 CFR 1.17(e), was filed in this application after final rejection. Since this application is eligible for continued examination under 37 CFR 1.114, and the fee set forth in 37 CFR 1.17(e) has been timely paid, the finality of the previous Office action has been withdrawn pursuant to 37 CFR 1.114. Applicant's submission filed on 4/20/2026 has been entered.
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.
(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.
Claim(s) 1, 4, 6-7, 9, 19, and 21-23 is/are rejected under 35 U.S.C. 102(a)(2) as being anticipated by Ravikirthi et al. (US 9881929; herein “Ravikirthi”).
Regarding claim 1, Ravikirthi discloses in Figs. 23A-B and related text a microelectronic device, comprising:
a stack structure comprising a vertically alternating sequence of insulative structures (132/232, see col. 8 para. 2) and conductive structures (146/246, see col. 25 para. 4) arranged in tiers, the tiers arranged in decks;
at least one live pillar (55, see col. 23, para. 2) extending through the decks of the stack structure to a source/drain region (61/9/10, see col. 6 para. 1, col. 7 para. 4, col. 27 para. 2) below the stack structure, the at least one live pillar comprising a channel material (see col. 21 para. 7);
at least one source/drain contact pillar (e.g. 76, see col. 27 para. 3) extending through the decks of the stack structure; and
in a transition area (region of support pillars 155) horizontally (in at least one direction shown in Fig. 23A) between the at least one live pillar (55) and the at least one source/drain contact pillar (76), at least one dummy pillar (e.g. 155, see col. 23 para. 2) extending through at least one of the decks of the stack structure, the at least one dummy pillar vertically separated from the source/drain region by a nonpatterned area of at least one of the tiers of a lower deck of the decks (see Fig. 23B), the at least one dummy pillar spaced from the at least one source/drain contact pillar.
Regarding claim 4, Ravikirthi further discloses wherein the at least one live pillar and the at least one dummy pillar both comprise the channel material (60/602, see col. 21 para. 3) and at least one cell material (52/54/56, see col. 18 para. 2).
Regarding claim 6, Ravikirthi further discloses wherein, in the at least one dummy pillar, the channel material (60/602) extends through the at least one cell material (52/54/56) (see Fig. 16B).
Regarding claim 7, Ravikirthi further discloses in the at least one dummy pillar, the channel material extends (60/602) to an elevation below a lowest elevation of the at least one cell material (e.g. in the instance where the cell material is 54/56).
Regarding claim 9, Ravikirthi further discloses wherein the at least one dummy pillar extends partially into a lowermost deck of the decks (e.g. in the interpretation where the lowermost “deck” includes the bottom 232).
Regarding claim 19, Ravikirthi discloses in Figs. 18A-B and related text a microelectronic device, comprising:
a stack structure comprising insulative structures (132/232, see col. 8 para. 2) vertically interleaved with conductive structures (146/246, see col. 25 para. 4) and arranged in tiers;
blocks of live pillar arrays (arrays of 55, see col. 23, para. 2) comprising live pillars (55) extending through the stack structure to a source/drain region (61/9/10, see col. 6 para. 1, col. 7 para. 4, col. 27 para. 2) below the stack structure;
at least one source/drain contact pillar (e.g. 76, see [0125] and [0125]) horizontally spaced from the blocks of the live pillar arrays, the at least one source/drain contact pillar (e.g. 76, see col. 27 para. 3) extending through the stack structure to at least one conductive landing structure (61) proximate the source/drain region; and
at least one dummy pillar (e.g. 155, see col. 23 para. 2) in at least one transition area horizontally between (in at least one direction shown in Fig. 23A) the at least one source/drain contact pillar and the blocks of the live pillar arrays, the at least one dummy pillar spaced from the at least one source/drain contact pillar and having a lower end vertically above the at least one conductive landing structure (see Fig. 18B);
the lower end of the at least one dummy pillar being directly vertically above a nonpatterned area of at least some of the tiers of the stack structure (see Fig. 23B).
Regarding claim 21, Ravikirthi further comprises
the at least one dummy pillar (155) comprises multiple dummy pillars;
the at least one source/drain contact pillar (76) is horizontally surrounded by the multiple dummy pillars (see Fig. 23A); and
each of the multiple dummy pillars is spaced from the at least one source/drain contact pillar by at least a minimum separation distance (see Fig. 23A).
Regarding claim 22, Ravikirthi further discloses wherein the live pillars and the at least one dummy pillar each comprise:
a channel material (602, see col. 21 para. 3); and
at least one cell material (52/54/56, see col. 18 para. 2) around the channel material in at least upper elevations of the stack structure.
Regarding claim 23, Ravikirthi further discloses the live pillars (55) and the at least one dummy pillar (155) each further comprise an insulative material (62, see col. 22 para 3) horizontally surrounded by the channel material in at least the upper elevations of the stack structure.
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.
This application currently names joint inventors. In considering patentability of the claims the examiner presumes that the subject matter of the various claims was commonly owned as of the effective filing date of the claimed invention(s) absent any evidence to the contrary. Applicant is advised of the obligation under 37 CFR 1.56 to point out the inventor and effective filing dates of each claim that was not commonly owned as of the effective filing date of the later invention in order for the examiner to consider the applicability of 35 U.S.C. 102(b)(2)(C) for any potential 35 U.S.C. 102(a)(2) prior art against the later invention.
Claim(s) 2 is/are rejected under 35 U.S.C. 103 as being unpatentable over Ravikirthi.
Regarding claim 2, Ravikirthi does not explicitly disclose wherein the at least one source/drain contact pillar defines a bow providing a maximum horizontal extension of the at least one source/drain contact pillar.
It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to modify the device of Ravikirthi by having the shape of the source/drain contact pillar including a bow because it would have been an obvious matter of design choice to modify the shape, since such a modification would have involved a mere change in the shape of a component. A change in shape is generally recognized as being within the level of ordinary skill in the art. In re Dailey, 357 F.2d 669, 149 USPQ 47 (CCPA 1966). See MPEP 2144.04
Claim(s) 3 is/are rejected under 35 U.S.C. 103 as being unpatentable over Ravikirthi as applied to claim 2 above, and in view of Tomimatsu (US 2019/0088672; herein “Tomimatsu”).
Regarding claim 3, Ravikirthi does not explicitly disclose the at least one dummy pillar is spaced from the at least one source/drain contact pillar by at least a minimum horizontal distance of at least twenty-five nanometers, the minimum horizontal distance defined at a vertical elevation of the bow.
In the same field of endeavor, Tomimatsu teaches a microelectronic device the at least one dummy pillar is spaced from the at least one source/drain contact pillar by at least a minimum horizontal distance of at least twenty-five nanometers (see [0093]).
It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to modify the invention of Ravikirthi by having a microelectronic device the at least one dummy pillar is spaced from the at least one source/drain contact pillar by at least a minimum horizontal distance of at least twenty-five nanometers in order to provide proper mechanical support.
Note that the range disclosed by Tomimatsu overlaps the claimed range. In the case where the claimed ranges “overlap or lie inside ranges disclosed by the prior art,” a prima facie case of obviousness exists (In re Wertheim, 541 F.2d 257, 191 USPQ 90 (CCPA 1976)). Additionally, one of ordinary skill in the art before the effective filing date of the claimed invention would have recognized the spacing to be a result effective variable affecting the mechanical support which the dummy pillar provides. Thus, it would have been obvious to modify the device of Ravikirthi to have the distance within the claimed range in order to provide desired mechanical support and electrical layout, and since optimum or workable ranges of such variables are discoverable through routine experimentation. see MPEP 2144.05 II.B and 2143. Furthermore, it has also been held that the applicant must show that a particular range is critical, generally by showing that the claimed range achieves unexpected results relative to the prior art range. In re Woodruff, 919 F.2d 1575, 1578, 16 USPQ2d 1934, 1936, (Fed. Cir. 1990). Note that the law is replete with cases in which when the mere difference between the claimed invention and the prior art is some dimensional limitation or other variable within the claims, patentability cannot be found. The instant disclosure does not set forth evidence ascribing unexpected results due to the claimed dimensions. See Gardner v. TEC Systems, Inc., 725 F.2d 1338 (Fed. Cir. 1984), which held that the dimensional limitations failed to point out a feature which performed and operated any differently from the prior art. Note the limitation “the minimum horizontal distance defined at a vertical elevation of the bow” is taught by the combination of the shape as applied to claim 2 above, and the distance taught by Tomimatsu.
Claim(s) 20 and 24 is/are rejected under 35 U.S.C. 103 as being unpatentable over Ravikirthi as applied to claims 19 and 22 above, and in view of Lee et al. (US 11,232,839; herein “Lee”).
Regarding claim 20, Ravikirthi does not explicitly disclose wherein the at least one source/drain contact pillar comprises multiple source/drain contact pillars; and further comprising at least one additional dummy pillar horizontally between neighboring source/drain contact pillars of the multiple source/drain contact pillars.
In the same field of endeavor, Lee teaches in Figs. 2-4 and related text a microelectronic device wherein the at least one source/drain contact pillar (464, see col. 10 line 15) comprises multiple source/drain contact pillars; and further comprising at least one additional dummy pillar (222, see col. 6 line 62) horizontally between neighboring source/drain contact pillars of the multiple source/drain contact pillars.
It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to modify the device of Ravikirthi by having the at least one source/drain contact pillar comprises multiple source/drain contact pillars and at least one additional dummy pillar horizontally between neighboring source/drain contact pillars of the multiple source/drain contact pillars, as taught by Lee, in order to improve function and capacity of the device by having additional memory cells. Further, it would have been obvious to one having ordinary skill in the art at the time the invention was made to repeat the structure of Ravikirthi, since it has been held that mere duplication of the essential working parts of a device involves only routine skill in the art. St. Regis Paper Co. v. Bemis Co., 193 USPQ 8. It has also been held that mere duplication of parts has no patentable significance unless a new and unexpected result is produced. In re Harza, 274 F.2d 669, 124 USPQ 378 (CCPA 1960). See also MPEP 2144.04
Regarding claim 24, Ravikirthi does not explicitly disclose wherein the channel material of the at least one dummy pillar is in physical contact with conductive material of at least one of the conductive structures.
In the same field of endeavor, Lee teaches in Figs. 2-4 and related text a microelectronic device the channel material of the at least one dummy pillar (338 of 222, see col. 8 lines 53-54 and col. 6 line 61) is in physical contact with conductive material of at least one of the conductive structures (460, see col. 9 line 58).
It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to modify the device of Ravikirthi by having the channel material of the at least one dummy pillar is in physical contact with conductive material of at least one of the conductive structures, as taught by Lee, in order to allow for electrical connection between decks of a memory device.
Claim(s) 25 is/are rejected under 35 U.S.C. 103 as being unpatentable over Ravikirthi in view of Hopkins et al. (US 2020/0119038; herein “Hopkins”).
Regarding claim 25, Ravikirthi substantially discloses the invention as applied to claim 1 above, but does not explicitly disclose
at least one processor in operable communication with the three-dimensional memory device; and
at least one peripheral device in operable communication with the at least one processor.
In the same field of endeavor, Hopkins teaches a microelectronic device comprising
at least one processor in operable communication with the three-dimensional memory device; and
at least one peripheral device in operable communication with the at least one processor (see [0111]).
It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to modify the device of Ravikirthi by having at least one processor in operable communication with the three-dimensional memory device and at least one peripheral device in operable communication with the at least one processor, as taught by Hopkins, in order to achieve a fully functional memory device capable of being controlled.
Response to Arguments
Applicant's arguments filed 3/23/2026 have been fully considered but are moot in view of the new grounds of rejection presented above.
Conclusion
Any inquiry concerning this communication or earlier communications from the examiner should be directed to Lauren R Bell whose telephone number is (571)272-7199. The examiner can normally be reached M-F 8am-5pm.
Examiner interviews are available via telephone, in-person, and video conferencing using a USPTO supplied web-based collaboration tool. To schedule an interview, applicant is encouraged to use the USPTO Automated Interview Request (AIR) at http://www.uspto.gov/interviewpractice.
If attempts to reach the examiner by telephone are unsuccessful, the examiner’s supervisor, William Kraig can be reached at (571) 272-8660. The fax phone number for the organization where this application or proceeding is assigned is 571-273-8300.
Information regarding the status of published or unpublished applications may be obtained from Patent Center. Unpublished application information in Patent Center is available to registered users. To file and manage patent submissions in Patent Center, visit: https://patentcenter.uspto.gov. Visit https://www.uspto.gov/patents/apply/patent-center for more information about Patent Center and https://www.uspto.gov/patents/docx for information about filing in DOCX format. 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.
/LAUREN R BELL/Primary Examiner, Art Unit 2896
Prosecution Insights