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 (i.e., changing from AIA to pre-AIA ) 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 without traverse of Invention Group I in the reply filed on October 17, 2025 is acknowledged. Following Applicant’s amendment to the specification and claims, Claims 17-20 are cancelled, Claim 3, 10, and 11 have been amended, and Claims 21-24 have been added. Upon review, Examiner finds no new matter has been introduced by the amendment and the new claims fall within the scope of the elected Invention Group I. Therefore, an examination on the merits of Claims 1-16 and 21-24 follows.
Title
The title of the invention is not descriptive. A new title is required that is clearly indicative of the invention to which the claims are directed. The following title is suggested:
--Transistor Including Isolation Structures Under Source/Drain Regions Comprising A Liner Layer And A Filler Of A Plurality of Sublayers Which Reduces Leakage Current--
Claim Objections
Claim 24 is objected to because of the following informalities:
“The semiconductor device of claim 23, further comprising a third sublayer” should read --The semiconductor device of claim 23, wherein the dielectric layer further comprises: a third sublayer-- for consistency in claim limitation syntax and for clarity.
Appropriate correction is required.
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.
Claims 1-3, 11-13, 16, 21 and 22 are rejected under 35 U.S.C. 102(a)(1) as being anticipated by Huang et al. (U.S. Pub. 2021/0202742), hereinafter Huang.
Regarding Claim 1, Huang teaches a semiconductor device ((100c); Figs. 1A - 2D-2, and 5A-1 – 5B-2, Paragraph [0087]) comprising:
-a substrate ((102); Fig. 5B-2, Paragraph [0025]);
-a fin ((104B) later identified as below each transistor stack; Figs. 1E, 2A-2, 5B-1, and 5B-2, Paragraph [0028]) protruding above the substrate (102);
-a gate structure ((152) including (154), (156), and (158); Fig. 27B, Paragraph [0066]) over the fin (104B);
-source/drain regions ((142); Figs. 5B-1 and 5B-2, Paragraph [0055]) over the fin (104B) and on opposing sides of the gate structure (152);
-channel layers ((108’); Fig. 5B-1, Paragraph [0064]) over the fin (104B) and between the source/drain regions (142), wherein the gate structure (152) wraps around the channel layers (108’); and
-isolation structures ((136c); Figs. 5B-1 and 5B-2, Paragraph [0088]) under the source/drain regions (142), wherein the isolation structures (136c) separate the source/drain regions (142) from the fin ((104B), see Paragraph [0047]), wherein each of the isolation structures (136c) comprises a liner layer (136c-1) and a dielectric layer (comprising (136c-2) and (136c-1)) over the liner layer (136c-1), wherein the dielectric layer has a plurality of sublayers (see Fig. 5A-2 and Paragraph [0089]).
Regarding Claim 2, Huang teaches a semiconductor device ((100c); Figs. 1A - 2D-2, and 5A-1 – 5B-2, Paragraph [0087]) of Claim 1, wherein:
-the liner layer (136c-1) extends along an upper surface of the fin (seen in Fig. 5B-2) and along sidewalls of the fin (seen in Fig. 5B-1).
Regarding Claim 3, Huang teaches a semiconductor device ((100c); Figs. 1A - 2D-2, and 5A-1 – 5B-2, Paragraph [0087]) of Claim 2, wherein:
-the liner layer is a dielectric material (‘dielectric layer’ (136c-1), Paragraph [0089]) and has a U-shaped cross-section (As in both cross-sections of Figs. 5B-1 and 5B-2), and the dielectric layer ((136c-2) and (136c-3)) fills a space defined by the U-shaped cross-section (by the bounds of (136c-1)).
Regarding Claim 11, Huang teaches a semiconductor device ((100c); Figs. 1A - 2D-2, and 5A-1 – 5B-2, Paragraph [0087]) comprising:
-a substrate ((102); Fig. 5B-2, Paragraph [0025]);
-a fin ((104B) later identified as below each transistor stack; Figs. 1E, 2A-2, 5B-1, and 5B-2, Paragraph [0028]) protruding above the substrate (102);
-channel layers ((108’); Fig. 5B-1, Paragraph [0064]) over the fin (104B);
-a gate structure ((152) including (154), (156), and (158); Fig. 27B, Paragraph [0066]) over the fin (104B) and around the channel layers (108’);
-source/drain regions ((142); Figs. 5B-1 and 5B-2, Paragraph [0055]) over the fin (104B) and on opposing sides of the gate structure (152), wherein the source/drain regions (142), are at opposing ends of the channel layers (108’); and
-isolation structures ((136c); Figs. 5B-1 and 5B-2, Paragraph [0088]) between the source/drain regions (142), and the fin (104B), wherein the isolation structures (136c) comprise a dielectric layer (comprising (136c-2) and (136c-1)) and a dielectric liner layer (136c-1) around the dielectric layer (As in both cross-sections of Figs. 5B-1 and 5B-2), wherein the dielectric layer has a multi-layered structure (see Fig. 5A-2 and Paragraph [0089]).
Regarding Claim 12, Huang teaches a semiconductor device ((100c); Figs. 1A - 2D-2, and 5A-1 – 5B-2, Paragraph [0087]) of Claim 11, wherein:
-a first dielectric constant of the dielectric liner layer (e.g. dielectric constant of zirconium oxide) is different from a second dielectric constant of the dielectric layer (e.g. dielectric constant of silicon nitride) (See Paragraph [0090]).
Regarding Claim 13, Huang teaches a semiconductor device ((100c); Figs. 1A - 2D-2, and 5A-1 – 5B-2, Paragraph [0087]) of Claim 11, further comprising:
-inner spacers ((134); Fig. 5B-1, Paragraph [0046]) between adjacent channel layers (108’) and between a lowermost channel layer (bottom (108’)) and the fin (104B), wherein an upper surface of the isolation structures (top, flat surface of (136c), Fig. 5B-1) distal from the substrate (102) is between a first surface of a first inner spacer (top surface of a bottom (134), e.g. a bottom-right (134) of a stack) facing away from the substrate (102) and a second surface of the first inner spacer (bottom surface of bottom-right (134)) facing the substrate (102), wherein the first inner spacer (bottom-right (134)) is between the lowermost channel layer (bottom (108’)) and the fin (104B).
Regarding Claim 16, Huang teaches a semiconductor device ((100c); Figs. 1A - 2D-2, and 5A-1 – 5B-2, Paragraph [0087]) of Claim 11, wherein:
-the channel layers (108) are nanosheets or nanowires (Paragraph [0120]).
Regarding Claim 21, Huang teaches a semiconductor device ((100c); Figs. 1A - 2D-2, and 5A-1 – 5B-2, Paragraph [0087]) comprising:
-a substrate ((102); Fig. 5B-2, Paragraph [0025]);
-a fin ((104B) later identified as below each transistor stack; Figs. 1E, 2A-2, 5B-1, and 5B-2, Paragraph [0028]) protruding above the substrate (102);
-source/drain regions ((142); Figs. 5B-1 and 5B-2, Paragraph [0055]) over the fin (104B)
-channel layers ((108’); Fig. 5B-1, Paragraph [0064]) over the fin (104B) and between the source/drain regions (142);
-a gate structure ((152) including (154), (156), and (158); Fig. 27B, Paragraph [0066]) over the fin (104B) and around the channel layers (108’), wherein the source/drain regions (142) are on on opposing sides of the gate structure (152); and
-isolation structures ((136c); Figs. 5B-1 and 5B-2, Paragraph [0088]) under the source/drain regions (142) and interposed between the source/drain regions (142) and the fin (104B), wherein the isolation structures (136c) comprise a dielectric layer (comprising (136c-2) and (136c-1)) and a dielectric liner layer (136c-1) around the dielectric layer (As in both cross-sections of Figs. 5B-1 and 5B-2), wherein the dielectric layer has a multi-layered structure (see Fig. 5A-2 and Paragraph [0089]).
Regarding Claim 22, Huang teaches a semiconductor device ((100c); Figs. 1A - 2D-2, and 5A-1 – 5B-2, Paragraph [0087]) of Claim 21, further comprising:
-inner spacers ((134); Fig. 5B-1, Paragraph [0046]), wherein the inner spacers are interposed vertically between adjacent channel layers (108’) and between the fin (104B) and a lowermost channel layer (bottom (108’)), wherein the inner spacers are interposed laterally between the gate structure (152) and the source/drain regions (142), wherein the inner spacers comprise a first inner spacer (bottom (134), e.g. a bottom-right (134) of a stack) closest to the substrate (102), wherein an upper surface of the isolation structures (top, flat surface of (136c), Fig. 5B-1) distal from the substrate (102) is between an upper surface of the first inner spacer (top surface of bottom-right (134) and a lower surface of the first inner spacer (bottom surface of bottom-right (134)).
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 4 is rejected under 35 U.S.C. 103 as being unpatentable over Huang in view of Pan et al. (U.S. 2022/0320088), hereinafter Pan.
Regarding Claim 4, Huang teaches a semiconductor device ((100c); Figs. 1A - 2D-2, and 5A-1 – 5B-2, Paragraph [0087]) of Claim 3, wherein:
-the liner layer has a first dielectric constant (of (136c-1)), and the dielectric layer has a second dielectric constant (of, e.g. (136c-2) made of e.g. silicon oxide).
Huang does not teach:
-the second dielectric constant is higher than the first dielectric constant.
Pan teaches a semiconductor device ((200); Fig. 26, Paragraph [0015]) containing channel layers ((220’); Fig. 27B, Paragraph [0050]) surrounded by a gate structure ((370); Fig. 27B, Paragraph [0053]) above a fin ((206’); Fig. 27B, Paragraph [0016]) with an isolation structure ((280); Fig. 27B, Paragraph [0031]) comprising a liner layer ((262) ; Fig. 27B, paragraph [0026]) and a dielectric layer ((264) made of silicon dioxide; Fig. 27B, Paragraph [0026]), wherein:
-the second dielectric constant higher than the first dielectric constant (‘(262) include a dielectric material having a dielectric constant that is less than a dielectric constant of silicon dioxide’, Paragraph [0026])
It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to incorporate the teachings of Pan into the device of Huang such that it has a second dielectric constant higher than the first dielectric constant. This would be due to the fact that doing so reduces the chances of void formation, thereby improving device performance (Pan, Paragraph [0065]).
Claims 5-10, 14, 15, 23 and 24 are rejected under 35 U.S.C. 103 as being unpatentable over Huang in view of Jung et al. (U.S. 2024/0088150), hereinafter Jung.
Regarding Claim 5, Huang teaches a semiconductor device ((100c); Figs. 1A - 2D-2, and 5A-1 – 5B-2, Paragraph [0087]) of Claim 2, wherein:
The dielectric layer ((136c-2) and (136c-3)) comprises
-a first sublayer comprising silicon nitride (‘silicon nitride’ (136c-2), Paragraph [0090]), wherein the first sublayer has a first atomic ratio between nitrogen and silicon (Necessarily as a consequence of (136c-2) being silicon nitride); and
- a second sublayer over the first sublayer, wherein the second sublayer comprises silicon nitride (‘silicon nitride’ (136c-3), Paragraph [0090]) and has a second atomic ratio between nitrogen and silicon (Necessarily as a consequence of (136c-3) being silicon nitride)
Huang does not explicitly state:
-the second atomic ratio is different from the first atomic ratio.
Jung teaches a semiconductor device ((100); Fig. 2A, Paragraph [0019]) containing channel layers ((NSS); Fig. 2A, Paragraph [0026]) surrounded by a gate structure ((160); Fig. 2A, Paragraph [0031]) above a fin (upper region (FA); Fig. 2A, Paragraph [0022]) with an isolation structure ((190); Fig. 2A, Paragraph [0045]) comprising a liner layer ((192); Fig. 2A, Paragraph [0045]) and a dielectric layer (comprising (194), (196), and (198); Fig. 2A, Paragraph [0045]), wherein:
the dielectric layer ((194), (196), and (198)) comprises:
-a first sublayer comprising silicon nitride ((196) being nitrogen-rich silicon nitride; Paragraph [0052]), wherein the first sublayer has a first atomic ratio between nitrogen and silicon (Wherein the ratio is taken as nitrogen atoms to silicon atoms, therefore for (196) it’s greater than 4/3, corresponding to a higher amount of nitrogen or lower amount of silicon than stoichiometric); and
-a second sublayer (198) over the first sublayer (196), wherein the second sublayer comprises silicon nitride ((198) being stochiometric silicon nitride (Si3N4)); Paragraph [0052]), and has a second atomic ratio between nitrogen and silicon (Wherein the ratio is taken as nitrogen atoms to silicon atoms, therefore for (198) it’s 4/3), wherein
-the second atomic ratio is different (less than) from the first atomic ratio.
It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to incorporate the teachings of Jung into the device of Huang such that the second atomic ratio is different from the first atomic ratio. Futhermore, the incorporation would be done such that the second atomic ratio is lower than the first atomic ratio (Jung, (198) has less nitrogen/more silicon than (196), thus the atomic ratio of nitrogen to silicon is less, Paragraph [0052]). This would be due to the fact that doing so would increase device performance and reliability (Jung, Paragraph [0063]).
Regarding Claim 6, Huang as modified by Jung teaches a semiconductor device ((100c); Figs. 1A - 2D-2, and 5A-1 – 5B-2, Paragraph [0087]) of Claim 5, wherein:
- the second atomic ratio (Jung, of (198)) is lower than the first atomic ratio (Jung, of (196)) (As explained in the incorporation of Jung into Huang in Claim 5 above, see Jung Paragraph [0052])
Regarding Claim 7, Huang teaches a semiconductor device ((100c); Figs. 1A - 2D-2, and 5A-1 – 5B-2, Paragraph [0087]) of Claim 2, wherein:
-each sublayer of the plurality of sublayers comprises silicon nitride (‘silicon nitride’ as material for both (136c-2) and (136c-3), Paragraph [0090])
Huang does not explicitly state:
- each sublayer of the plurality of sublayers comprises silicon nitride and has a different respective atomic ratio between nitrogen and silicon, wherein there is a gradient in the atomic ratios of the plurality of sublayers.
Jung teaches a semiconductor device ((100); Fig. 2A, Paragraph [0019]) containing channel layers ((NSS); Fig. 2A, Paragraph [0026]) surrounded by a gate structure ((160); Fig. 2A, Paragraph [0031]) above a fin (upper region (FA); Fig. 2A, Paragraph [0022]) with an isolation structure ((190); Fig. 2A, Paragraph [0045]) comprising a liner layer ((192); Fig. 2A, Paragraph [0045]) and a dielectric layer comprising a plurality of sublayers (e.g. (194) and (196); Fig. 2A, Paragraph [0045]), wherein:
- each sublayer of the plurality of sublayers comprises silicon nitride and has a different respective atomic ratio between nitrogen and silicon ((194) being stochiometric silicon nitride (Si3N4), a ratio of 4/3. And (196) being nitrogen-rich silicon nitride, a ratio greater than 4/3, corresponding to a higher amount of nitrogen or lower amount of silicon than stoichiometric; Paragraph [0052]), wherein there is a gradient in the atomic ratios of the plurality of sublayers. (Examiner understands “gradient” here as simply a change in value)
It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to incorporate the teachings of Jung into the device of Huang such that each sublayer of the plurality of sublayers comprises silicon nitride and has a different respective atomic ratio between nitrogen and silicon, wherein there is a gradient in the atomic ratios of the plurality of sublayers. Futhermore, the incorporation would be done such that the atomic ratios of the plurality of sublayers increase along a first direction (Jung, Z-direction of Fig. 2A) from a sublayer closest to the substrate (Jung, (194)) to a sublayer furthest from the substrate (Jung, (196)). (Jung, (196) has more nitrogen/less silicon than (194), thus the atomic ratio of increases, Paragraph [0052]). This would be due to the fact that doing so would increase device performance and reliability (Jung, Paragraph [0063]).
Regarding Claim 8, Huang as modified by Jung teaches a semiconductor device ((100c); Figs. 1A - 2D-2, and 5A-1 – 5B-2, Paragraph [0087]) of Claim 7, wherein:
- the atomic ratios of the plurality of sublayers increase along a first direction (Jung, Z-direction of Fig. 2A) from a sublayer closest to the substrate (Jung, (194)) to a sublayer furthest from the substrate (Jung, (196)). (As explained in the incorporation of Jung into Huang in Claim 7 above, see Jung Paragraph [0052])
Regarding Claim 9, Huang teaches a semiconductor device ((100c); Figs. 1A - 2D-2, and 5A-1 – 5B-2, Paragraph [0087]) of Claim 2, wherein:
The dielectric layer ((136c-2) and (136c-3)) comprises
-a first type of sublayer (136c-2) and a second type of sublayer (136c-3), wherein the first type of sublayer comprises silicon nitride (Paragraph [0090]) and has a first atomic ratio between nitrogen and silicon (Necessarily as a consequence of (136c-2) being silicon nitride), and the second type of sublayer comprises silicon nitride (Paragraph [0090]) and has a second atomic ratio between nitrogen and silicon (Necessarily as a consequence of (136c-) being silicon nitride).
Huang does not teach:
-the dielectric layer comprises a first type of sublayers and a second type of sublayers interleaved with the first type of sublayers, wherein each of the first type of sublayers comprises silicon nitride and has a first atomic ratio between nitrogen and silicon, and each of the second type of sublayers comprises silicon nitride and has a second atomic ratio between nitrogen and silicon, wherein the first atomic ratio is different from the second atomic ratio.
Jung teaches a semiconductor device ((100); Fig. 2A, Paragraph [0019]) containing channel layers ((NSS); Fig. 2A, Paragraph [0026]) surrounded by a gate structure ((160); Fig. 2A, Paragraph [0031]) above a fin (upper region (FA); Fig. 2A, Paragraph [0022]) with an isolation structure ((190); Fig. 2A, Paragraph [0045]) comprising a dielectric layer (comprising (192), (194), (196), and (198); Fig. 2A, Paragraph [0045]), wherein:
the dielectric layer ((192), (194), (196), and (198)) comprises:
a first type of sublayers ((192) and (196)) and a second type of sublayers ((194) and (198)) interleaved with the first type of sublayers, wherein each of the first type of sublayers comprises silicon nitride ((192) and (196) comprise nitrogen-rich silicon nitride, Paragraph [0049]) and has a first atomic ratio between nitrogen and silicon (Wherein the ratio is taken as nitrogen atoms to silicon atoms, therefore for (192) and (196) it’s greater than 4/3, corresponding to a higher amount of nitrogen or lower amount of silicon than stoichiometric, Paragraph [0051]), and each of the second type of sublayers comprises silicon nitride ((194) and (198) comprise stochiometric silicon nitride, Paragraph [0052]) and has a second atomic ratio between nitrogen and silicon (Wherein the ratio is taken as nitrogen atoms to silicon atoms, therefore for (194) and (198) it’s 4/3), wherein the first atomic ratio is different (greater) from the second atomic ratio.
It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to incorporate the teachings of Jung into the device of Huang such that the dielectric layer comprises a first type of sublayers and a second type of sublayers interleaved with the first type of sublayers, wherein each of the first type of sublayers comprises silicon nitride and has a first atomic ratio between nitrogen and silicon, and each of the second type of sublayers comprises silicon nitride and has a second atomic ratio between nitrogen and silicon, wherein the first atomic ratio is different from the second atomic ratio. This would be due to the fact that doing so would increase device performance and reliability (Jung, Paragraph [0063]).
Regarding Claim 10, Huang teaches a semiconductor device ((100c); Figs. 1A - 2D-2, and 5A-1 – 5B-2, Paragraph [0087]) of Claim 2, wherein:
The dielectric layer ((136c-2) and (136c-3)) comprises
-a first sublayer (136c-2) on the liner layer (136c-1), wherein the first sublayer comprises silicon nitride (‘silicon nitride’ (136c-2), Paragraph [0090]), and has a first atomic ratio between nitrogen and silicon (Necessarily as a consequence of (136c-2) being silicon nitride); and
- a second sublayer over the first sublayer, wherein the second sublayer comprises silicon nitride (‘silicon nitride’ (136c-3), Paragraph [0090]) and has a second atomic ratio between nitrogen and silicon (Necessarily as a consequence of (136c-3) being silicon nitride).
Huang does not teach:
- a third sublayer over the second sublayer, wherein the third sublayer comprises silicon nitride and has a third atomic ratio between nitrogen and silicon, wherein the second atomic ratio is higher than the first atomic ratio and the third atomic ratio.
Jung teaches a semiconductor device ((100); Fig. 2A, Paragraph [0019]) containing channel layers ((NSS); Fig. 2A, Paragraph [0026]) surrounded by a gate structure ((160); Fig. 2A, Paragraph [0031]) above a fin (upper region (FA); Fig. 2A, Paragraph [0022]) with an isolation structure ((190); Fig. 2A, Paragraph [0045]) comprising a liner layer ((192); Fig. 2A, Paragraph [0045]) and a dielectric layer (comprising (194), (196), and (198); Fig. 2A, Paragraph [0045]), wherein:
the dielectric layer ((194), (196), and (198)) comprises:
-a first sublayer (194) on the liner layer (192), wherein the first sublayer comprises silicon nitride ((194) being stochiometric silicon nitride (Si3N4)); Paragraph [0052]), wherein the first sublayer has a first atomic ratio between nitrogen and silicon (Wherein the ratio is taken as nitrogen atoms to silicon atoms, therefore for (194) it’s 4/3);
-a second sublayer (196) over the first sublayer (194), wherein the second sublayer comprises silicon nitride ((196) being nitrogen-rich silicon nitride; Paragraph [0052]), and has a second atomic ratio between nitrogen and silicon (Wherein the ratio is taken as nitrogen atoms to silicon atoms, therefore for (196) it’s greater than 4/3, corresponding to a higher amount of nitrogen or lower amount of silicon than stoichiometric); and
-a third sublayer (198) over the second sublayer (196), wherein the third sublayer comprises silicon nitride ((198) being stochiometric silicon nitride (Si3N4)); Paragraph [0052]), and has a third atomic ratio between nitrogen and silicon (Wherein the ratio is taken as nitrogen atoms to silicon atoms, therefore for (198) it’s 4/3), wherein
- the second atomic ratio is higher (of nitrogen-rich (196)) than the first atomic ratio (of (194)) and the third atomic ratio (of (198)).
It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to incorporate the teachings of Jung into the device of Huang such that a third sublayer over the second sublayer, wherein the third sublayer comprises silicon nitride and has a third atomic ratio between nitrogen and silicon, wherein the second atomic ratio is higher than the first atomic ratio and the third atomic ratio. This would be due to the fact that doing so would increase device performance and reliability (Jung, Paragraph [0063]).
Regarding Claim 14, Huang teaches a semiconductor device ((100c); Figs. 1A - 2D-2, and 5A-1 – 5B-2, Paragraph [0087]) of Claim 11, wherein:
The dielectric layer ((136c-2) and (136c-3)) comprises
-a first sublayer (136c-2) and a second sublayer (136c-3), wherein the first sublayer and the second sublayer comprise silicon nitride (‘silicon nitride’, Paragraph [0090]) and have atomic ratios between nitrogen and silicon (Necessarily as a consequence of (136c-2) and (136c-3) being silicon nitride)
Huang does not explicitly state:
-the atomic ratios are different.
Jung teaches a semiconductor device ((100); Fig. 2A, Paragraph [0019]) containing channel layers ((NSS); Fig. 2A, Paragraph [0026]) surrounded by a gate structure ((160); Fig. 2A, Paragraph [0031]) above a fin (upper region (FA); Fig. 2A, Paragraph [0022]) with an isolation structure ((190); Fig. 2A, Paragraph [0045]) comprising a liner layer ((192); Fig. 2A, Paragraph [0045]) and a dielectric layer (comprising (194), (196), and (198); Fig. 2A, Paragraph [0045]), wherein:
the dielectric layer ((194), (196), and (198)) comprises:
-a first sublayer ((196) being nitrogen-rich silicon nitride; Paragraph [0052]) and a second sublayer ((198) being stochiometric silicon nitride (Si3N4)); Paragraph [0052]), wherein the first sublayer and the second sublayer comprise silicon nitride and have different atomic ratio between nitrogen and silicon ((196) has a ratio greater than (198))
It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to incorporate the teachings of Jung into the device of Huang such that the atomic ratios are different. This would be due to the fact that doing so would increase device performance and reliability (Jung, Paragraph [0063]).
Regarding Claim 15, Huang teaches a semiconductor device ((100c); Figs. 1A - 2D-2, and 5A-1 – 5B-2, Paragraph [0087]) of Claim 11, wherein:
The dielectric layer ((136c-2) and (136c-3)) comprises
-a first sublayer (136c-2) and a second sublayer (136c-3), wherein the first sublayer comprises silicon nitride (Paragraph [0090]) and has a first atomic ratio between nitrogen and silicon (Necessarily as a consequence of (136c-2) being silicon nitride), and the second sublayer comprises silicon nitride (Paragraph [0090]) and has a second atomic ratio between nitrogen and silicon (Necessarily as a consequence of (136c-) being silicon nitride).
Huang does not teach:
- wherein the dielectric layer comprises a first set of sublayers and a second set of sublayers interleaved with the first set of sublayers, wherein the first set of sublayers and the second set of sublayers comprise silicon nitride, wherein the first set of sublayers have a first atomic ratio between nitrogen and silicon, and the second set of sublayers have a second atomic ratio between nitrogen and silicon that is different from the first atomic ratio
Jung teaches a semiconductor device ((100); Fig. 2A, Paragraph [0019]) containing channel layers ((NSS); Fig. 2A, Paragraph [0026]) surrounded by a gate structure ((160); Fig. 2A, Paragraph [0031]) above a fin (upper region (FA); Fig. 2A, Paragraph [0022]) with an isolation structure ((190); Fig. 2A, Paragraph [0045]) comprising a dielectric layer (comprising (192), (194), (196), and (198); Fig. 2A, Paragraph [0045]), wherein:
the dielectric layer ((192), (194), (196), and (198)) comprises:
a first set of sublayers ((192) and (196)) and a second set of sublayers ((194) and (198)) interleaved with the set of sublayers, wherein the first set of sublayers ((192) and (196) comprise nitrogen-rich silicon nitride, Paragraph [0049]) and the second set of sublayers ((194) and (198) comprise stochiometric silicon nitride, Paragraph [0052]) comprise silicon nitride, wherein the first set of sublayers have a first atomic ratio between nitrogen and silicon (Wherein the ratio is taken as nitrogen atoms to silicon atoms, therefore for (192) and (196) it’s greater than 4/3, corresponding to a higher amount of nitrogen or lower amount of silicon than stoichiometric, Paragraph [0051]), and the second set of sublayers have a second atomic ratio between nitrogen and silicon (Wherein the ratio is taken as nitrogen atoms to silicon atoms, therefore for (194) and (198) it’s 4/3) that is different (lesser) from the first atomic ratio.
It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to incorporate the teachings of Jung into the device of Huang such that the dielectric layer comprises a first set of sublayers and a second set of sublayers interleaved with the first set of sublayers, wherein the first set of sublayers and the second set of sublayers comprise silicon nitride, wherein the first set of sublayers have a first atomic ratio between nitrogen and silicon, and the second set of sublayers have a second atomic ratio between nitrogen and silicon that is different from the first atomic ratio. This would be due to the fact that doing so would increase device performance and reliability (Jung, Paragraph [0063]).
Regarding Claim 23, Huang teaches a semiconductor device ((100c); Figs. 1A - 2D-2, and 5A-1 – 5B-2, Paragraph [0087]) of Claim 2, wherein:
The dielectric layer ((136c-2) and (136c-3)) comprises
-a first sublayer of silicon nitride (‘silicon nitride’ (136c-2), Paragraph [0090]) over the dielectric liner layer (136c-1), wherein the first sublayer of silicon nitride has a first atomic ratio between nitrogen and silicon (Necessarily as a consequence of (136c-2) being silicon nitride); and
- a second sublayer of silicon nitride (‘silicon nitride’ (136c-3), Paragraph [0090]) over the first sublayer, wherein the second sublayer of silicon nitride has a second atomic ratio between nitrogen and silicon (Necessarily as a consequence of (136c-3) being silicon nitride).
Huang does not explicitly state:
-the second atomic ratio is higher than the first atomic ratio.
Jung teaches a semiconductor device ((100); Fig. 2A, Paragraph [0019]) containing channel layers ((NSS); Fig. 2A, Paragraph [0026]) surrounded by a gate structure ((160); Fig. 2A, Paragraph [0031]) above a fin (upper region (FA); Fig. 2A, Paragraph [0022]) with an isolation structure ((190); Fig. 2A, Paragraph [0045]) comprising a liner layer ((192); Fig. 2A, Paragraph [0045]) and a dielectric layer (comprising (194), (196), and (198); Fig. 2A, Paragraph [0045]), wherein:
the dielectric layer ((194), (196), and (198)) comprises:
-a first sublayer of silicon nitride ((194) being stochiometric silicon nitride (Si3N4)); Paragraph [0052]) over the dielectric liner layer (192), wherein the first sublayer of silicon nitride has a first atomic ratio between nitrogen and silicon (Wherein the ratio is taken as nitrogen atoms to silicon atoms, therefore for (194) it’s 4/3); and
-a second sublayer of silicon nitride ((196) being nitrogen-rich silicon nitride; Paragraph [0052]) over the first sublayer of silicon nitride (194), wherein the second sublayer of silicon nitride has a second atomic ratio between nitrogen and silicon (Wherein the ratio is taken as nitrogen atoms to silicon atoms, therefore for (196) it’s greater than 4/3, corresponding to a higher amount of nitrogen or lower amount of silicon than stoichiometric), wherein the second atomic ratio is higher (of nitrogen-rich (196)) than the first atomic ratio (194).
It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to incorporate the teachings of Jung into the device of Huang such that the second atomic ratio is higher than the first atomic ratio. This would be due to the fact that doing so would increase device performance and reliability (Jung, Paragraph [0063]).
Regarding Claim 24, Huang as modified by Jung teaches a semiconductor device ((100c); Figs. 1A - 2D-2, and 5A-1 – 5B-2, Paragraph [0087]) of Claim 23, wherein:
The dielectric layer (Jung, (194), (196), and (198)) further comprises:
-a third sublayer of silicon nitride ((198) being stochiometric silicon nitride (Si3N4)); Fig. 2A, Paragraph [0052]) over the second sublayer of silicon nitride (196), wherein the third sublayer of silicon nitride has a third atomic ratio between nitrogen and silicon (Wherein the ratio is taken as nitrogen atoms to silicon atoms, therefore for (198) it’s 4/3), wherein the third atomic ratio is lower (of stochiometric (198)) than the second atomic ratio (of nitrogen-rich (196)).
Conclusion
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/D.M./ Examiner, Art Unit 2812
/DAVIENNE N MONBLEAU/ Supervisory Patent Examiner, Art Unit 2812