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 .
Election/Restrictions
Applicant’s election without traverse of claims 1-7,21-33 in the reply filed on 10/10/2025 is acknowledged.
Claim Rejections - 35 USC § 112
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 1 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. First applicant states an inner spacer is bended, then later in the claim applicant uses the limitations “inner spacer and bended inner spacers”. Are all the inner spacers bended? If not, how much of them are bended?
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.
Claim(s) 1-2,5,21-23 is/are rejected under 35 U.S.C. 102(a)(1) as being anticipated by Mochizuki et al (US Patent No. 9954058).
With respect to claim 1, Mochizuki et al discloses a semiconductor device (Fig.10) comprising: a semiconductor stack (14A-C) over a substrate (10), wherein the semiconductor stack includes semiconductor layers (Col3, Lines 60-67) separated from each other (Fig.10) and stacked up along a direction (y direction) substantially perpendicular to a top surface of the substrate (Fig.10);a gate structure (38) over a channel region (14) of the semiconductor stack and wrapping each of the semiconductor layers (Fig.10) ;an inner spacer (24P) between edge portions of the semiconductor layers (Fig.10) and being bended towards the gate structure (Fig.10); and a source/drain (S/D) feature (30) over a S/D region of the semiconductor stack (between the stacks) and contacting sidewalls of the semiconductor layers (fig.10), wherein the S/D feature includes facets (left side of 32 which looks like an acute angle) forming a first portion of an air gap (inside the acute angle region) between the inner spacer and the S/D feature (fig.10), and the bended inner spacer forms a second portion of the air gap (portion of the airgap inside the bended region) between the inner spacer and the S/D feature (Fig.10).
With respect to claim 2, Mochizuki et al discloses, wherein the first portion of the air gap has a cross-section view of an isosceles triangle-shape (Fig.10).
With respect to claim 5, Mochizuki et al discloses wherein, at an interface wherein the first portion of the air gap meets the second portion of the air gap (where the triangle portion hits the sidewall of the 24P,Fig.10), a heigh of the first portion of the air gap is greater than a height of the second portion of the air gap (Fig.10).
With respect to claim 21, Mochizuki et al discloses a semiconductor device (Fig.10) comprising: semiconductor layers (14a-C) stacked one over another (Fig.10) over a substrate (10); a gate structure wrapping around the semiconductor layers (38) ;an inner spacer between edge portions of the semiconductor layers and interfacing the gate structure (24P); and a source/drain (S/D) feature contacting sidewalls of the semiconductor layers (30),wherein the S/D feature includes facets (the acute angle), wherein the facets and the inner spacer form an air gap (32),wherein air gap includes a first portion extending into the S/D feature (the portion of 32 inside the triangle region,Fig.10) and a second portion extending into the inner spacer (portion of the 32 inside 24P).
With respect to claim 22, Mochizuki et al discloses wherein the inner spacer comprises a bended shape (Fig.10) around the second portion of the air gap (Fig.10).
With respect to claim 23, Mochizuki et al discloses wherein, along a direction perpendicular to a top surface of the substrate (y direction), a height of the first portion (between two end points of the acute angle) is greater than a height of the second portion (inside the inner sides of the 24P).
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) 3, 7,24-26 is/are rejected under 35 U.S.C. 103 as being unpatentable over Mochizuki et al (US Patent No. 9954058).
With respect to claim 3, Mochizuki et al discloses wherein the facets of the S/D feature forming the first portion of the air gap are grown along a direction <111> (Fig.10). "[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).
With respect to claim 7, Mochizuki et al does not explicitly disclose wherein a thickness of the inner spacer is about 1 nm to about 5 nm. "[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).
With respect to claim 24, Mochizuki et al discloses wherein the facets of the S/D feature are grown along a direction <111> (Fig.10, the facet’s structure looks exactly like applicant’s). Furthermore, "[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).
With respect to claim 25, Mochizuki et al does not explicitly disclose wherein a thickness of the inner spacer is about 1 nm to about 5 nm. "[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).
With respect to claim 26, Mochizuki et al discloses that dielectric constant of the layer 24 is higher than silicon oxide; however, wherein the inner spacer comprises silicon oxynitride, silicon carbonitride, silicon oxycarbide, silicon oxycarbonitride, or a combination thereof. On the other hand, it would have been obvious to one of ordinary skill in the art at the time of the filing of the invention to modify Mochizuki et al such that the inner spacer would have been made from silicon oxynitride, because it is relatively inexpensive and available and it has a high dielectric constantan.
Claim(s) 4,6,27-33 is/are rejected under 35 U.S.C. 103 as being unpatentable over Mochizuki et al (US Patent No. 9954058), in view of Cheng et al (US Pub No. 20210210598).
With respect to claim 4, Mochizuki et al does not explicitly disclose wherein the second portion of the air gap has a cross-section view of a half-ellipse-shape, a triangle-shape with curved sides, or a rectangular-shape with round corners. On the other hand, Cheng et al discloses that element (136,Fig.16, particularly it’s shorter sides in the channel stack region), which corresponds to the second airgap region, has a cross section which looks like a half-ellipse-shape (Fig.16). It would have been obvious to one of ordinary skill in the art at the time of the filing of the invention to modify Mochizuki et al according to the teachings of the Cheng et al such that the second portion of the air gap has a cross-section view of a half-ellipse-shape as a design choice.
With respect to claim 6, Cheng et al discloses wherein the bended inner spacer has a cross-section view of a half-ring-shape (Fig.16).
Claim(s) 4,6,27-33 is/are rejected under 35 U.S.C. 103 as being unpatentable over Mochizuki et al (US Patent No. 9954058), in view of Song (US Pub No. 20200286992).
With respect to claim 27, Mochizuki et al does not explicitly disclose wherein the S/D feature partially extends into the substrate. On the other hand, Song et al discloses that the S/D feature (120,Fig.7) partially extends into the substrate (104,102). It would have been obvious to one of ordinary skill in the art at the time of the filing of the invention to modify Mochizuki et al such that the S/D feature partially extends into the substrate, in order to have a more mechanical stable S/D feature or as design choice.
With respect to claim 28, Mochizuki et al discloses :an active region (two stack and the space between them,Fig.10) disposed over a substrate (10), the active region comprising a vertical stack of channel layers (14a-c);a gate structure (38) wrapping around the channel layers (Fig.10) ;a bended inner spacer (24p) between edge portions of the channel layers (Fig.10) and interfacing the gate structure (Fig.10); and a source/drain (S/D) feature (30) contacting sidewalls of the channel layers (Fig.10),wherein the S/D feature includes facets (the acute angle on 30 sidewalls facing the gate structure,Fig.10), wherein the facets and the bended inner spacer form an air gap (32), wherein air gap includes a first portion extending into the S/D feature (inside triangle region) and a second portion extending into the bended inner spacer (inside 24P region), wherein, along a direction perpendicular to a top surface of the substrate (on the y direction), a first height of the first portion (the height of a line connecting the two end points of the acute angle,Fig.10) is greater than a second height of the second portion ( the vertical line connecting the two inner end points of the 24p,Fig.10). However, Mochizuki et al does not explicitly disclose and partially extending into the substrate. On the other hand, Song et al discloses that the S/D feature (120,Fig.7) partially extends into the substrate (104,102). It would have been obvious to one of ordinary skill in the art at the time of the filing of the invention to modify Mochizuki et al such that the S/D feature partially extends into the substrate, in order to have a more mechanical stable S/D feature or as design choice.
With respect to claim 29, the arts cited above do not explicitly disclose wherein the first height is between about 4 nm and about 20 nm, wherein the second height is between about 2 nm and about 18 nm. However, it would have been obvious to one of ordinary skill in the art at the time of the filing of the invention to modify the arts cited above such that the first height is between about 4 nm and about 20 nm, wherein the second height is between about 2 nm and about 18 nm, in order to minimize the size of the device therefore, decreasing the cost of the manufacturing. Furthermore, "[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).
With respect to claim 30, Mochizuki et al discloses, wherein the facets of the S/D feature are grown along a direction <111> (Fig.10). Furthermore, "[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).
With respect to claim 31, the arts cited above do not wherein a thickness of the bended inner spacer is about 1 nm to about 5 nm. Furthermore, "[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).
With respect to claim 32, wherein the channel layers comprise silicon (lines 41-51, Col4).
With respect to claim 33, Mochizuki et al discloses that dielectric constant of the layer 24 is higher than silicon oxide; however, wherein the inner spacer comprises silicon oxynitride, silicon carbonitride, silicon oxycarbide, silicon oxycarbonitride, or a combination thereof. On the other hand, it would have been obvious to one of ordinary skill in the art at the time of the filing of the invention to modify Mochizuki et al and Song et al such that the inner spacer would have been made from silicon oxynitride, because it is relatively inexpensive and available and it has a high dielectric constantan.
Conclusion
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/ALI NARAGHI/Examiner, Art Unit 2817