DETAILED ACTION
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 .
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.
Election/Restrictions
Applicant's election with traverse of Group I, claims 1-7, in the reply filed on 12/2/25 is acknowledged. The traversal is on the ground(s) that “Applicant respectfully submits that no unreasonable search and examination burden exists because a search of the subject matter of Group I would yield relevant references, if any, equally applicable to Group II or III. Therefore, the search and examination burden are not an undue burden.” (see Remarks at page 5)
This is not found persuasive because a search for art disclosing “simultaneously filling a top portion of a first high aspect ratio (HAR) structure and a top portion a second HAR structure…wherein the first HAR structure has a critical dimension (CD) of between 150 nm and 250 nm, and the second HAR structure has a CD of between 250 nm and 400 nm” requires employing different search strategies or search queries from art disclosing “widening a critical dimension (CD) of the HAR opening” (e.g. Group II) and art disclosing “performing a hole patterning process… performing a first removal process, the first removal process comprising selectively removing the carbon-containing sacrificial layers from the contact holes…performing a cell formation process…” (e.g. Group III) such that a search and examination burden exists.
The requirement is still deemed proper and is therefore made FINAL.
Claims 8-20 are withdrawn from further consideration pursuant to 37 CFR 1.142(b), as being drawn to a nonelected invention, there being no allowable generic or linking claim. Applicant timely traversed the restriction (election) requirement in the reply filed on 12/2/25.
Relevant Art
The prior art made of record and not relied upon is considered pertinent to applicant's disclosure:
Yu, US 20180144977 A1 (e.g. See para. [0013], “The vertical vias may have a critical dimension between about 50 nm and about 500 nm.”)
Wang, US 20200258757 A1 (e.g. See para. [0045], “In some embodiments, the word line contact openings 136 can have a CD from 100 nm to 300 nm…”)
Chakravanti, US 20210143100 A1 (e.g. See para. [0071], “The CDs of the WL contacts 108e, 108f of FIG. 6B can be made substantially larger than the CD of the WL contact 608f of FIG. 6A, for a same size of the array 100 and 600. Merely as an example, given the same size of the memory arrays 100 and 600, the CD of the WL contact 608f can be about 250 nanometers (nm), whereas the CD of the WL contact 608e can be about 600 nm.”)
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) 1, 2, and 7 is/are rejected under 35 U.S.C. 103 as being unpatentable over Chang[1] et al., US Publication No. 2011/0220990 A1 in view of Wong et al., US Publication No. 2013/0277854 A1 and Chang[2] et al., US Publication No. US 2021/0391181 A1.
Chang[1] teaches:
1. A method of forming a semiconductor memory device, comprising (see fig. 1D, 11-13):
simultaneously filling a top portion of a first high aspect ratio (HAR) structure (1104 or 1106) and a top portion a second HAR structure (1102) with a silicon-containing sacrificial layer (1302) by a cycle of a deposition process and an etch process (e.g. See para. [0041] disclosing “…a trench fill technique referred to herein as dep-etch-dep (deposit-etch-deposit). In this technique, as shown in FIG. 36A…”)
wherein the first HAR structure (1104 or 1106) has a critical dimension (CD) (different from) the second HAR structure (1102)… See Chang[1] at para. [0001] – [0071], figs. 1-33.
Chang[1] is silent:
wherein the first HAR structure has a critical dimension (CD) of between 150 nm and 250 nm, and the second HAR structure has a CD of between 250 nm and 400 nm.
In an analogous art, Wong teaches:
“It will be appreciated by those skilled in the art that the depth and diameter of the TSV opening 136 can vary with the via type, the application, the design specifications and/or the current technology process node (e.g., 45 nm, 32 nm, etc.) for the integrated circuit system 100. By way of example, the depth of the TSV opening 136 can vary from about 20 microns to about 500 microns and the diameter can vary from about 200 nm to about 200 microns. Generally, the aspect ratio for the TSV opening 136 can vary from about 0.3:1 to greater than about 20:1.” See Wong at para. [0026].
In an analogous art, Chang[2] teaches:
“Features to be patterned using patterned layer 122 may have a desired critical dimension, or width, for patterned layer 122. As an example, the width may be about 70 nm to about 250 nm…These values are provided for example purposes only, as the features to be patterned using patterned layer 122 may have any suitable critical dimension. The width may be the critical dimension achievable for a photoresist film by the lithography system after developing. See Chang[2] at para. [0033]
Wong and Chang[2] disclose ranges that overlap 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); In re Woodruff, 919 F.2d 1575, 16 USPQ2d 1934 (Fed. Cir. 1990). “[A] prior art reference that discloses a range encompassing a somewhat narrower claimed range is sufficient to establish a prima facie case of obviousness." In re Peterson, 315 F.3d 1325, 1330, 65 USPQ2d 1379, 1382-83 (Fed. Cir. 2003). See MPEP § 2144.05, Obviousness of Ranges
Referring to MPEP § 2144.05, “…the applicant must show that the particular range is critical, generally by showing that the claimed range achieves unexpected results over the prior art range.” (See also MPEP § 716.02 for a discussion of criticality and unexpected results.)
Based on the teachings of Wong and Chang[2], it would have been obvious to one of ordinary skill in the art to form Chang[1]’s “first HAR structure to have a critical dimension (CD) of between 150 nm and 250 nm, and the second HAR structure to have a CD of between 250 nm and 400 nm” because (i) The depth and diameter of the HAR can vary depending on the application, design specification and/or process node; and (ii) A critical dimension of a 250 nm width is achievable by lithography.
Chang[1] further teaches:
2. The method of claim 1, wherein the deposition process comprises a high-density plasma chemical vapor deposition (HDP-CVD) process (e.g. See CVD at para. [0041] and it would have been obvious to one of ordinary skill in the art to apply a high density plasma in the CVD process because Chang[1] teaches high density is used in figs. 14-15, para. [0044].)
7. The method of claim 1, further comprising: removing the silicon-containing sacrificial layer (1302) selectively to a silicon oxide (SiO2)-containing liner layer (1202, e.g. thermal oxide in fig. 12) formed on inner sidewalls of the first HAR structure, figs. 13-14.
It would have been obvious to a person of ordinary skill in the art before the effective filling date of the claimed invention to modify the teachings of Chang[1] with the teachings of Wong because the dimension of a HAR trench can vary depending on the application, design specification and/or process node. See Wong at para. [0026].
It would have been obvious to a person of ordinary skill in the art before the effective filling date of the claimed invention to modify the teachings of Chang[1] with the teachings of Chang[2] because a width of 250 nm may be the critical dimension achievable for a photoresist film by the lithography system after developing. See Chang[2] at para. [0033]
Claim(s) 3 and 6 is/are rejected under 35 U.S.C. 103 as being unpatentable over Chang[1] in view of Wong and Chang[2], as applied to claim 1 above, in further view of Cui, US Patent No. 9,853,038 B1.
Regarding claim 3:
Chang[1], Wong and Chang[2] teach all the limitations of claim 1 above, but do not expressly teach:
wherein the silicon-containing sacrificial layer comprises amorphous silicon.
In an analogous art, Cui teaches:
3. The method of claim 1, (see fig. 6) wherein the silicon-containing sacrificial layer (22L) comprises amorphous silicon, col 11, ln 20–45.
Regarding claim 6:
Cui teaches the sacrificial layer (22L) may be amorphous silicon, diamond-like carbon, germanium, etc. at col 11, ln 20–45.
One of ordinary skill in the art forming the sacrificial layer to comprise the material diamond-like carbon would arrive at the claimed limitation:
6. The method of claim 1, further comprising: selectively removing a carbon-containing sacrificial layer (22L) filled in a memory hole (49’), figs. 12-13.
It would have been obvious to a person of ordinary skill in the art before the effective filling date of the claimed invention to modify the teachings of Chang[1] with the teachings of Cui because one of ordinary skill in the art would be motivated to look for alternative sacrificial layer materials and Cui teaches amorphous silicon or diamond-like carbon are known materials suitable as a sacrificial layer to fill a trench. Also see MPEP § 2144.07, Art Recognized Suitability for an Intended Purpose.
Claim(s) 1, 3, 5 and 6 is/are rejected under 35 U.S.C. 103 as being unpatentable over Cui, US Patent No. 9,853,038 B1 in view of Chang[1] et al., US Publication No. 2011/0220990 A1, Wong et al., US Publication No. 2013/0277854 A1, and Chang[2] et al., US Publication No. US 2021/0391181 A1.
Cui teaches:
1. A method of forming a semiconductor memory device, comprising (see figs. 1-25):
simultaneously filling a top portion of a first high aspect ratio (HAR) structure (19’) and a top portion a second HAR structure (49’) with a silicon-containing sacrificial layer (22L)… See Cui at col 11, ln 20–45.
Cui does not expressly teach:
by a cycle of a deposition process and an etch process,
In an analogous art, Chang[1] teaches:
(see fig. 1D, 11-13) simultaneously filling a top portion of a first high aspect ratio (HAR) structure (1104 or 1106) and a top portion a second HAR structure (1102) with a silicon-containing sacrificial layer (1302) by a cycle of a deposition process and an etch process (e.g. See para. [0041] disclosing “…a trench fill technique referred to herein as dep-etch-dep (deposit-etch-deposit). In this technique, as shown in FIG. 36A…”)
wherein the first HAR structure (1104 or 1106) has a critical dimension (CD) (different from) the second HAR structure (1102)… See Chang[1] at para. [0001] – [0071], figs. 1-33.
Cui does not expressly teach:
wherein the first HAR structure has a critical dimension (CD) of between 150 nm and 250 nm, and the second HAR structure has a CD of between 250 nm and 400 nm.
In an analogous art, Wong teaches:
“It will be appreciated by those skilled in the art that the depth and diameter of the TSV opening 136 can vary with the via type, the application, the design specifications and/or the current technology process node (e.g., 45 nm, 32 nm, etc.) for the integrated circuit system 100. By way of example, the depth of the TSV opening 136 can vary from about 20 microns to about 500 microns and the diameter can vary from about 200 nm to about 200 microns. Generally, the aspect ratio for the TSV opening 136 can vary from about 0.3:1 to greater than about 20:1.” See Wong at para. [0026].
In an analogous art, Chang[2] teaches:
“Features to be patterned using patterned layer 122 may have a desired critical dimension, or width, for patterned layer 122. As an example, the width may be about 70 nm to about 250 nm…These values are provided for example purposes only, as the features to be patterned using patterned layer 122 may have any suitable critical dimension. The width may be the critical dimension achievable for a photoresist film by the lithography system after developing. See Chang[2] at para. [0033]
Wong and Chang[2] disclose ranges that overlap 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); In re Woodruff, 919 F.2d 1575, 16 USPQ2d 1934 (Fed. Cir. 1990). “[A] prior art reference that discloses a range encompassing a somewhat narrower claimed range is sufficient to establish a prima facie case of obviousness." In re Peterson, 315 F.3d 1325, 1330, 65 USPQ2d 1379, 1382-83 (Fed. Cir. 2003). See MPEP § 2144.05, Obviousness of Ranges
Referring to MPEP § 2144.05, “…the applicant must show that the particular range is critical, generally by showing that the claimed range achieves unexpected results over the prior art range.” (See also MPEP § 716.02 for a discussion of criticality and unexpected results.)
Based on the teachings of Wong and Chang[2], it would have been obvious to one of ordinary skill in the art to form Chang[1]’s “first HAR structure to have a critical dimension (CD) of between 150 nm and 250 nm, and the second HAR structure to have a CD of between 250 nm and 400 nm” because (i) The depth and diameter of the HAR can vary depending on the application, design specification and/or process node; and (ii) A critical dimension of a 250 nm width is achievable by lithography.
Cui further teaches:
3. The method of claim 1, (see fig. 6) wherein the silicon-containing sacrificial layer (22L) comprises amorphous silicon, col 11, ln 20–45.
Regarding claim 5:
Cui further teaches:
a bottom portion of the first HAR structure (19’) and a bottom portion of the second HAR structure (49’) are not filled (e.g. not completely filled) with the silicon-containing sacrificial layer (22L), fig. 6.
Cui is silent the silicon-containing sacrificial layer has a thickness of between 20 nm and 300 nm.
However, absent any disclosure by the Applicant that a thickness of between 20 nm and 300 nm is critical or provides for unexpected results, such a thickness can be considered within the skill level of one of ordinary skill in the art or by the guidance provided by Cui
See MPEP § 2144.05, Obviousness of Ranges:
“Generally, differences in concentration or temperature will not support the patentability of subject matter encompassed by the prior art unless there is evidence indicating such concentration or temperature is critical.” (Emphasis added.)
In re Hoeschele, 406 F.2d 1403, 160 USPQ 809 (CCPA 1969)…Claimed elastomeric polyurethanes which fell within the broad scope of the references were held to be unpatentable thereover because, among other reasons, there was no evidence of the criticality of the claimed ranges of molecular weight or molar proportions. (Emphasis added.)
[W]here the general conditions of a claim are disclosed in the prior art, it is not inventive to discover the optimum or workable ranges by routine experimentation. In re Aller, 220 F.2d 454, 456, 105 USPQ 233, 235 (CCPA 1955)
Cui does not expressly teach:
wherein the first HAR structure and the second HAR structure each have a depth of greater than 15 μm,
Wong teaches the depth of the TSV opening 136 can vary from about 20 microns to about 500 microns, which overlaps the claimed range. See Wong at para. [0026].
Cui further teaches:
6. The method of claim 1, further comprising: selectively removing a carbon-containing sacrificial layer (22L; Cui teaches the sacrificial layer may be diamond-like carbon, etc. at col 11, ln 20–45) filled in a memory hole (49’), figs. 12-13.
It would have been obvious to a person of ordinary skill in the art before the effective filling date of the claimed invention to modify the teachings of Cui with the teachings of Wong because the dimension of a HAR trench can vary depending on the application, design specification and/or process node. See Wong at para. [0026].
It would have been obvious to a person of ordinary skill in the art before the effective filling date of the claimed invention to modify the teachings of Chang[1] with the teachings of Chang[2] because a width of 250 nm may be the critical dimension achievable for a photoresist film by the lithography system after developing. See Chang[2] at para. [0033]
Claim(s) 4 is/are rejected under 35 U.S.C. 103 as being unpatentable over Cui, US Patent No. 9,853,038 B1 in view of Chang[1], Wong and Chang[2], as applied to claim 1 above, in further view of Lien et al., US Publication No. 2023/0016518 A1.
Regarding claim 4:
Cui, Chang[1], Wong and Chang[2] teach all the limitations of claim 1 above, and Cui further teaches:
wherein the first HAR structure (19; corresponding to 86 in fig. 25) is a contact hole in which a word line contact is to be formed, col 27, ln 1–11.
Cui does not expressly teach:
the second HAR structure is a contact hole in which a peripheral contact is to be formed.
In an analogous art, Lien teaches a memory device comprises a word line contact (86) and a peripheral contact (8P), fig. 15A. See Lien at para. [0169] – [0171].
It would have been obvious to a person of ordinary skill in the art before the effective filling date of the claimed invention to modify the teachings of Cui with the teachings of Lien because peripheral contacts can provide connection to switch devices that control a bias voltage to respective word lines. See Lien at para. [0229].
Conclusion
Any inquiry concerning this communication or earlier communications from the examiner should be directed to Michele Fan whose telephone number is 571-270-7401. The examiner can normally be reached on M-F from 7:30 am to 4 pm.
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/Michele Fan/
Primary Examiner, Art Unit 2818
12 February 2026