DETAILED ACTION
This Office action is in response to the Amendment filed on 11 February 2026. Claims 1-20 are pending in the application.
This application is a divisional of application Serial No. 17/150,044, filed on 15 January 2021, still pending.
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 § 112
In light of Applicant’s Amendment, the previous rejection of claims 13 and 18 under 35 U.S.C. 112(b) has been withdrawn.
The following is a quotation of the first paragraph of 35 U.S.C. 112(a):
(a) IN GENERAL.—The specification shall contain a written description of the invention, and of the manner and process of making and using it, in such full, clear, concise, and exact terms as to enable any person skilled in the art to which it pertains, or with which it is most nearly connected, to make and use the same, and shall set forth the best mode contemplated by the inventor or joint inventor of carrying out the invention.
The following is a quotation of the first paragraph of pre-AIA 35 U.S.C. 112:
The specification shall contain a written description of the invention, and of the manner and process of making and using it, in such full, clear, concise, and exact terms as to enable any person skilled in the art to which it pertains, or with which it is most nearly connected, to make and use the same, and shall set forth the best mode contemplated by the inventor of carrying out his invention.
Claim 18 is rejected under 35 U.S.C. 112(a) or 35 U.S.C. 112 (pre-AIA ), first paragraph, as failing to comply with the written description requirement. The claim(s) contains subject matter which was not described in the specification in such a way as to reasonably convey to one skilled in the relevant art that the inventor or a joint inventor, or for applications subject to pre-AIA 35 U.S.C. 112, the inventor(s), at the time the application was filed, had possession of the claimed invention.
Dependent claim 18, which depends from independent claim 16, requires the device of claim 16 to further comprise a second dielectric layer over the first dielectric layer, wherein the second dielectric layer comprises the second dielectric material. Whereas in Fig. 25B of the instant application, a second dielectric layer 134 is shown over a first dielectric layer 122, Applicant’s specification does not disclose a device comprising the first dielectric layer, a second dielectric material extending over the first air gap from the first dielectric layer to the contact structure, and a second dielectric layer over the first dielectric layer, as required in claim 18.
The following is a quotation of 35 U.S.C. 112(b):
(b) CONCLUSION.—The specification shall conclude with one or more claims particularly pointing out and distinctly claiming the subject matter which the inventor or a joint inventor regards as the invention.
The following is a quotation of 35 U.S.C. 112 (pre-AIA ), second paragraph:
The specification shall conclude with one or more claims particularly pointing out and distinctly claiming the subject matter which the applicant regards as his invention.
Claim 18 is rejected under 35 U.S.C. 112(b) or 35 U.S.C. 112 (pre-AIA ), second paragraph, as being indefinite for failing to particularly point out and distinctly claim the subject matter which the inventor or a joint inventor (or for applications subject to pre-AIA 35 U.S.C. 112, the applicant), regards as the invention.
Dependent claim 18, which depends from independent claim 16, requires the device of claim 16 to further comprise a second dielectric layer over the first dielectric layer, wherein the second dielectric layer comprises the second dielectric material. Independent claim 16 requires a second dielectric material extending over the first air gap from the first dielectric layer to the contact structure. It is unclear if the second dielectric layer of claim 18 is in addition to the second dielectric material required in independent claim 16, since claim 18 recites “further comprising” or if the second dielectric layer is the same as the second dielectric material required in independent claim 16. If the latter, it is unclear how the device of claim 16 “further comprises” a second dielectric layer.
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.
Claims 1-3, 5, and 10 are rejected under 35 U.S.C. 102(a)(1) as being clearly anticipated by Lee et al., US 2019/0043959, cited by Applicant on the Information Disclosure Statement submitted on 24 June 2025.
With respect to claim 1, Lee et al. disclose a device, shown in Fig. 4, comprising:
a fin FA (see paragraphs [0023]-[0028]) extending from a semiconductor substrate 110, see Figs. 2 and 4;
a gate stack 122 (see paragraphs [0029]-[0032]) over the fin FA, see Fig. 4;
a spacer 124 on a sidewall of the gate stack 122, see Fig. 4;
a source/drain region 114 in the fin FA adjacent the spacer 124, see Fig. 4;
an inter-layer dielectric layer (ILD) 126 extending over the gate stack 122, the spacer 124, and the source/drain region 114 (see paragraph [0033]), see Figs. 1 and 4;
a contact plug 140 extending through the ILD 126 and contacting the source/drain region 114 (see paragraphs [0039], [0040], and [0062]), see Fig. 4;
a dielectric layer 132A comprising a first portion on a top surface of the ILD 126 (the first portion disposed above LV1, shown in Fig. 4) and a second portion extending between the ILD 126 and the contact plug 140 (the second portion disposed below LV1), shown in Fig. 4), as shown in Fig. 4,
wherein a top surface of the second portion (the second portion below LV1) is closer to the substrate 110 than the top surface of the ILD 126 (see annotated Fig. 4 below),
wherein a bottom surface of the dielectric layer 132A that is closest to the semiconductor substrate 110 (as shown below in annotated Fig. 4) is farther from the semiconductor substrate 110 than a top surface of the gate stack 122; and
an air gap 134A (see paragraph [0059]: “The second spacer layer 134A may include the air space defined by a lower side wall of the gate structure 120 and a lower side wall of the first contact structure 140.”).
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With respect to claim 2, the device of Lee et al. further comprises a conductive material 182 extending on the ILD 126, the second portion (see annotated Fig. 2 above), and the contact plug 140, see Fig. 2.
With respect to claim 3, in the device of Lee et al., the conductive material 182 is separated from the air gap 134 by the second portion, since the second portion is formed on the sidewalls of the air gap 134, as shown in Fig. 2.
With respect to claim 5, in the device of Lee et al., the dielectric layer 132 comprises silicon nitride, see paragraph [0035]..
With respect to claim 10, in the device of Lee et al., a bottom surface of the second portion is farther from the substrate 110 than a bottom surface of the ILD 126, as shown in annotated Fig. 4 below.
Claims 11, 14, 16, 17, 19, and 20 are rejected under 35 U.S.C. 102(a)(1) as being clearly anticipated by Cheng et al., US 2019/0334011, cited by Applicant on the Information Disclosure Statement submitted on 24 June 2025.
With respect to claim 11, Cheng et al. disclose a device, shown in Fig. 9, comprising:
a gate structure 102B over a semiconductor fin 101 (see paragraphs [0028]), see Fig. 1;
an epitaxial source/drain region 103A/103B in the semiconductor fin 101 (see paragraph [0029]), wherein the epitaxial source/drain region 103A/103B comprises a semiconductor material, see paragraphs [0031] and [0057], see Fig. 1;
a first spacer layer 1022 over a sidewall of the gate structure 102B (see paragraph [0030]), see Fig. 1;
a source/drain contact 701 on a top surface of the epitaxial source/drain region 103A/103B (see paragraph [0043]), see Fig. 7;
a second spacer layer 150 over a sidewall of the source/drain contact 701 (see paragraphs [0038]-[0039], see Figs. 5-7; and
a first dielectric layer 190 on a sidewall of the second spacer layer 150,
wherein the first dielectric layer 190 extends over an air gap 200, wherein the air gap exposes a bottom surface of the first dielectric layer 190, a sidewall surface of the first spacer layer 1022, a sidewall surface of the second spacer layer 150, and a top surface of the semiconductor material of the epitaxial source/drain region 103A/103B, as shown in Fig. 9. A top surface of the semiconductor material of the epitaxial source/drain region 103A/103B is diffusion barrier 150, as shown in Fig. 5. The air gap 200 exposes diffusion barrier 150, as shown in Fig. 9. Hence, the air gap 200 exposes a top surface of the semiconductor material of the epitaxial source/drain region 103A/103B, as required in independent claim 11.
With respect to claim 14, in the device of Cheng et al., the first dielectric layer 190 is higher than the first spacer layer 1022, as shown in Fig. 9.
With respect to claim 16, Cheng et al. disclose a device, shown in Fig. 9, comprising:
a contact structure 701 on an epitaxial source/drain region 103A/103B (see paragraphs [0028] and [0043]), see Figs. 6-7;
a first air gap 200 (air gap disposed on the right side of contact structure 701) over the epitaxial source/drain region 103A/103B and adjacent the contact structure 701, as shown in Fig. 9,
wherein the contact structure 701 extends along a first side of the first air gap 200;
a first spacer 1022 extending along a second side of the first air gap 200;
first dielectric layer 190 above the first spacer 1022, wherein the first dielectric layer 190 extends along the second side of the first air gap 200 (air gap disposed on the right side of contact structure 701), wherein the first dielectric layer is a first dielectric material, see paragraph [0045]; and
a second dielectric material 1021 (see Figs. 1 and 9) extending over the first air gap 200 from the first dielectric layer 190 to the contact structure 701, as shown in Fig. 9, wherein the second dielectric material (SiN, see paragraph [0030]: “The dielectric material lid 1021 can include or be formed of silicon nitride (SiN).”)is different from the first dielectric material (SiO2, see paragraph [0045]).
With respect to claim 17, as shown in Fig. 9 of Cheng et al., the first air gap 200 (air gap disposed on the right side of contact structure 701) is adjacent a first side of the contact structure 701 and further comprising a second air gap 200 (air gap disposed on the left side of contact structure 701) adjacent a second side of the contact structure 701, as shown in Fig. 9.
With respect to claim 19, in the device of Cheng et al., the contact structure 701 has a width near the bottom of the contact structure 701 that is smaller than a width near the top of the contact structure 701. Since the contact structure 701 has an inverse T-shaped cross-sections 702, as shown in Fig. 7, the portions of 702 under air gap spacer regions 703 have a width that is smaller than the width of the top cross section 701, as shown in annotated Fig. 9 below.
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With respect to claim 20, in the device of Cheng et al., the contact structure 701 comprises a spacer layer 150 on a sidewall of a conductive material 170, see Figs. 6 and 7 and paragraphs [0038]-[0043].
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.
Claims 6-9 are rejected under 35 U.S.C. 103 as being unpatentable over Lee et al., US 2019/0043959, as applied to claim 1 above.
With respect to claim 6, although Lee et al. disclose the top surface of the second portion is below the top surface of ILD 126, as shown in Fig. 2, Lee et al. lack anticipation of the top surface of the second portion is in the range between 0 nm and 15 nm below the top surface of the ILD 126. However, it has been well established that . "where 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) Hence, requiring in claim 6 that the top surface of the second portion is in the range between 0 nm and 15 nm below the top surface of the ILD 126 would have been obvious to the skilled artisan and clearly ascertainable through routine experimentation, since Lee et al. teach that general conditions of the claim, that is, that the top surface of the second portion is below the top surface of ILD 126, as shown in Fig. 2. The distance the top surface of the second portion is below the top surface of the ILD 126 does not patentably distinguish Applicant’s claimed device from the known device of Lee et al.
With respect to claims 7-9 as to the vertical thickness and width of the second portion (dependent claims 7 and 8, respectively), and the vertical thickness of the first portion (dependent claim 9), Lee et al. do not disclose these claimed vertical thicknesses and width. However, it is clear from Fig. 2 of Lee et al. that the second portion, shown above in annotated Fig. 2, has a vertical thickness and a width and that the first portion, also shown in annotated Fig. 2 above, has a vertical thickness. Although Lee et al. do not disclose the claimed range of vertical thicknesses and width, it has been well established that "where 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) Hence, the claimed vertical thickness and width of the second portion and the vertical thickness of the first portion would have been obvious to the skilled artisan and clearly ascertainable through routine experimentation, and, accordingly, do not patentably distinguish Applicant’s claimed device from the known device of Lee et al.
Claim 12 is rejected under 35 U.S.C. 103 as being unpatentable over Cheng et al., US 2019/0334011, as applied to claim 11 above, further in view of Tsai et al., US 2020/0126843, cited by Applicant on the Information Disclosure Statement (IDS) submitted on 24 June 2025.
Cheng et al. is applied as above. Cheng et al. lack anticipation only of a conductive material physically contacting top surfaces of the first dielectric layer, the second spacer layer, and the source/drain contact, as required by claim 12. In the same field of endeavor, Tsai et al. disclose a conductive material 180 physically contacting top surfaces of a capping dielectric layer 145, a second spacer layer 111, and a source/drain contact 158b, as shown in Fig. 2Q and 2R, since the conductive via structure 196 has a width greater than the source/drain contact 158b. It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention that if a conductive material is disposed in a via having a width greater than the width of the source/drain contact 130 in the known device of Cheng et al., the conductive material would physically contact top surfaces of the first dielectric layer 190, the second spacer layer 150, and the source/drain contact 701, thereby ensuring that the conductive material is electrically connected to the source/drain contact 701.
Claim 15 is rejected under 35 U.S.C. 103 as being unpatentable over Cheng et al., US 2019/0334011, as applied to claim 11 above, further in view of Cheng et al., US 9,716,158, cited by Applicant on the Information Disclosure Statement submitted on 01 August 2023, hereinafter Cheng et al. ‘158.
Cheng et al. is applied as above. With respect to claim 15, Cheng et al. do not disclose that a second dielectric layer over the first spacer layer 1022, wherein the first dielectric layer physically contacts a sidewall of the second dielectric layer. In the same field of endeavor, Cheng et al. ‘158 disclose that multiple dielectric layers can be formed along sidewalls of a gate structure, see column 9, lines 34-39. Therefore, in light of the disclosure of Cheng et al. ‘158, it would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention that a second dielectric layer could have been formed over the first spacer layer 1022 in the known device of Cheng et al., which would result in the first dielectric layer physically contacting a sidewall of the second dielectric layer, thereby ensuring that the source/drain contact does not physically contact the gate structure 102B in the known device of Cheng et al..
Allowable Subject Matter
Claims 4 and 13 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:
With respect to claim 4, Kee et al. fails to teach or suggest the first portion is separated from the second portion by the conductive material, as required in dependent claim 4 and shown in Fig. 26B of the instant application.
With respect to claim 13, Cheng et al. fails to teach or suggest that a bottom surface of the conductive material is lower than a top surface of the second spacer layer, as shown in Fig. 27B of the instant application.
Response to Arguments
Applicant's arguments filed 11 February 2026 have been fully considered but they are not persuasive. With respect to amended independent claim 1, the embodiment of Lee shown in Fig. 4 (see annotated Fig. 4 above) clearly comprises a dielectric layer 132A comprising a first portion on a top surface of the ILD 126 (the first portion disposed above LV1, shown in Fig. 4) and a second portion extending between the ILD 126 and the contact plug 140 (the second portion disposed below LV1), shown in Fig. 4), wherein a bottom surface of the dielectric layer 132A that is closest to the semiconductor substrate 110 is farther from the semiconductor substrate 110 than a top surface of the gate stack 122. Therefore, amended claim 1 fails to patentably distinguish Applicant’s claimed device from the prior art device of Lee shown in Fig. 4.
Independent claim 11 has been amended to require the air gap expose a top surface of the semiconductor material of the epitaxial source/drain region. Cheng et al. clearly teach that semiconductor regions 103A/103B comprise a semiconductor material, see paragraph [0057]. As noted in the rejection of claim 11 above, “a top surface” of the semiconductor material of the epitaxial source/drain region 103A/103B is diffusion barrier 150, as shown in Fig. 5. The air gap 200 exposes diffusion barrier 150, as shown in Fig. 9. Hence, the air gap 200 exposes “a top surface” of the semiconductor material of the epitaxial source/drain region 103A/103B, as required in independent claim 11.
With respect to amended claim 16 has been amended to require “the first dielectric layer is a first dielectric material; and a second dielectric material extending over the first air gap from the first dielectric layer to the contact structure, wherein the second dielectric material is different from the first dielectric material. As shown in Fig. 9 of Cheng et al., the device of Cheng et al. comprises first dielectric layer 190 above the first spacer 1022, wherein the first dielectric layer 190 extends along the second side of the first air gap 200 (air gap disposed on the right side of contact structure 701), wherein the first dielectric layer is a first dielectric material, see paragraph [0045]; and
a second dielectric material 1021 (see Figs. 1 and 9) extending over the first air gap 200 from the first dielectric layer 190 to the contact structure 701, as shown in Fig. 9, wherein the second dielectric material (SiN) is different from the first dielectric material (SiO2). Therefore, amended independent claim 16 does not patentably distinguish Applicant’s claimed device from the prior art device of Cheng et al.
Conclusion
Applicant's amendment necessitated the new ground(s) of rejection presented in this Office action. Accordingly, THIS ACTION IS MADE FINAL. See MPEP § 706.07(a). Applicant is reminded of the extension of time policy as set forth in 37 CFR 1.136(a).
A shortened statutory period for reply to this final action is set to expire THREE MONTHS from the mailing date of this action. In the event a first reply is filed within TWO MONTHS of the mailing date of this final action and the advisory action is not mailed until after the end of the THREE-MONTH shortened statutory period, then the shortened statutory period will expire on the date the advisory action is mailed, and any nonprovisional extension fee (37 CFR 1.17(a)) pursuant to 37 CFR 1.136(a) will be calculated from the mailing date of the advisory action. In no event, however, will the statutory period for reply expire later than SIX MONTHS from the mailing date of this final action.
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MARY A. WILCZEWSKI
Primary Examiner
Art Unit 2898
/MARY A WILCZEWSKI/Primary Examiner, Art Unit 2898
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