DETAILED ACTION
The present application, filed on or after March 16, 2013, is being examined under the first inventor to file provisions of the AIA .
Applicant's response to the Office Final Action filed on 6/5/2026 is acknowledged.
In view of the appeal brief filed on 6/5/2026, PROSECUTION IS HEREBY REOPENED. New grounds of rejection are set forth below.
To avoid abandonment of the application, appellant must exercise one of the following two options:
(1) file a reply under 37 CFR 1.111 (if this Office action is non-final) or a reply under 37 CFR 1.113 (if this Office action is final); or,
(2) initiate a new appeal by filing a notice of appeal under 37 CFR 41.31 followed by an appeal brief under 37 CFR 41.37. The previously paid notice of appeal fee and appeal brief fee can be applied to the new appeal. If, however, the appeal fees set forth in 37 CFR 41.20 have been increased since they were previously paid, then appellant must pay the difference between the increased fees and the amount previously paid.
A Supervisory Patent Examiner (SPE) has approved of reopening prosecution by signing below:
/STEVEN B GAUTHIER/ Supervisory Patent Examiner, Art Unit 2813
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, 2, 4, 6, 7, 21, 23, 26, 27, 29, and 32 are rejected under 35 U.S.C. 102(a)(1) as being anticipated by Wang et al. (US 2021/0343639) (hereafter Wang).
Regarding claim 1, Wang (see upside down figure of Fig. 25) discloses a semiconductor device 100 (Fig. 25, paragraph 0030) comprising:
a first source/drain element (280 and 194 of 190S in Fig. 25, paragraph 0056) on a first side (side of 100 with 190S in Fig. 25) of the semiconductor device 100 (Fig. 25) and a second source/drain element (194 of 190D in Fig. 25, paragraph 0056) on an opposing side (side of 100 with 190D in Fig. 25) of the semiconductor device;
a backside contact (300 and 315 in Fig. 25) below and in direct contact with the first source/drain element (280 and 194 of 190S in Fig. 25), a critical dimension (horizontal length of top surface of 300 in Fig. 25) of a first end (top surface of 300 in Fig. 25) of the backside contact (300 and 315 in Fig. 25) is smaller than a critical dimension (horizontal length of bottom surface of 315 in Fig. 25) of an opposing end (bottom surface of 315 in Fig. 25) of the backside contact; and
a source/drain placeholder material (192 of 190D in Fig. 25, paragraph 0056) below and in direct contact with the second source/drain element (194 of 190D in Fig. 25), a critical dimension (horizontal length of bottom of 192 of 190D in Fig. 25) of a middle portion (longest portion of 192 of 190D between 170 in Fig. 25) of the source/drain placeholder material (192 of 190D in Fig. 25) is larger than a critical dimension of both a first end (top surface of 192 of 190D in Fig. 25) of the source/drain placeholder material and a second end (bottom surface of 192 of 190D Fig. 25) of the source/drain placeholder material.
Regarding claim 2, Wang further discloses the semiconductor device of claim 1, wherein the backside contact (300 and 315 in Fig. 25) extends from the first source/drain element (280 and 194 of 190S in Fig. 25) to a backside power distribution network 312 (Fig. 25, paragraph 0090) to define a backside contact height (vertical length of 312 in Fig. 25).
Regarding claim 4, Wang further discloses the semiconductor device of claim 1, wherein the source/drain placeholder material (192 of 190D in Fig. 25, paragraph 0057, wherein “the first SiGe layer 192”) comprises SiGe.
Regarding claim 6, Wang further discloses the semiconductor device of claim 1, wherein a frontside contact 240 (Fig. 25, paragraph 0068) including a first contact end on a first end of the second source/drain element (194 of 190D in Fig. 25) and an opposing second contact end in electrical communication with a backend of line (BEOL) interconnect 250 (Fig. 25, paragraph 0069).
Regarding claim 7, Wang further discloses the semiconductor device of claim 1, wherein a back side power rail (top 312 in Fig. 25, paragraph 0090) positioned between the backside contact (300 and 315 in Fig. 25) and a backside power distribution network (bottom 312 in Fig. 25, paragraph 0090).
Regarding claim 21, Wang (see upside down figure of Fig. 25) discloses a semiconductor structure comprising:
a first source drain (280 and 194 of 190S in Fig. 25, paragraph 0056) adjacent to a second source drain (194 of 190D in Fig. 25, paragraph 0056);
a backside contact (300 and 315 in Fig. 25) directly beneath a first source drain (280 and 194 of 190S in Fig. 25), wherein a width (horizontal length of top surface of 300 in Fig. 25) measured at a top surface (top surface of 300 in Fig. 25) of the backside contact (300 and 315 in Fig. 25) is less than a width (horizontal length of bottom surface of 315 in Fig. 25) measured at a bottom surface (bottom surface of 315 in Fig. 25) of the backside contact (300 and 315 in Fig. 25); and
a placeholder (192 of 190D in Fig. 25, paragraph 0056) directly beneath a second source drain (194 of 190D in Fig. 25), wherein a width (horizontal length of bottom of 192 of 190D in Fig. 25) measured at a middle (longest portion of 192 of 190D between 170 in Fig. 25) of the placeholder (192 of 190D in Fig. 25) is greater than both a width measured at a top surface (top surface of 192 of 190D in Fig. 25) of the placeholder and a width measured at a bottom surface (bottom surface of 192 of 190D Fig. 25) of the placeholder (192 of 190D in Fig. 25).
Regarding claim 23, Wang further discloses the semiconductor structure of claim 21, wherein the width measured at the bottom surface of the backside contact (300 and 315 in Fig. 25) is greater than a width of the first source drain (280 and 194 of 190S in Fig. 25), and wherein the width measured at the middle (longest portion of 192 of 190D between 170 in Fig. 25) of the placeholder (192 of 190D in Fig. 25) is greater than a width of the second source drain (194 of 190D in Fig. 25).
Regarding claim 26, Wang further discloses the semiconductor structure of claim 21, wherein the placeholder (192 of 190D in Fig. 25, paragraph 0057, wherein “the first SiGe layer 192”) is made of SiGe.
Regarding claim 27, Wang (see upside down figure of Fig. 25) discloses a semiconductor structure comprising:
a first source drain (280 and 194 of 190S in Fig. 25, paragraph 0056) adjacent to a second source drain (194 of 190D in Fig. 25, paragraph 0056);
a backside contact (300 and 315 in Fig. 25) directly beneath a first source drain (280 and 194 of 190S in Fig. 25) wherein sidewalls of the backside contact (300 and 315 in Fig. 25) are positively tapered (see sidewall of 300 contacting 280 in Fig. 25); and
a placeholder (192 of 190D in Fig. 25, paragraph 0056) directly beneath a second source drain (194 of 190D in Fig. 25), wherein sidewalls of the placeholder (192 of 190D in Fig. 25) are both positively tapered and negatively tapered (see sidewalls of 192 of 190D contacting 194 of 190D in Fig. 25).
Regarding claim 29, Wang further discloses the semiconductor structure of claim 27, wherein a first width of the placeholder (192 of 190D in Fig. 25) is substantially equal (see bottom portion of 192 of 190D and top portion of 194 of 190D in Fig. 25) to a width of the second source drain (194 of 190D in Fig. 25), and wherein a second width of the placeholder (192 of 190D in Fig. 25) is greater (see Fig. 25) than the width of the second source drain (194 of 190D in Fig. 25).
Regarding claim 32, Wang further discloses the semiconductor structure of claim 27, wherein the placeholder (192 of 190D in Fig. 25, paragraph 0057, wherein “the first SiGe layer 192”) is made of SiGe.
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 of this title, 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 3, 22, 24, and 30 are rejected under 35 U.S.C. 103 as being unpatentable over Wang as applied to claims 2, 21, and 27 above, and further in view of Lin et al. (US 2021/0376094) (hereafter Lin).
Regarding claim 3, Wang discloses the semiconductor device of claim 2, however Wang does not disclose a height of the backside contact is larger than a height of the source/drain placeholder material.
Lin discloses a height of the backside contact 130 (Fig. 34B, paragraph 0049) is larger than a height of the source/drain placeholder material (region between 95 and 129 in Fig. 34B; and see Fig. 13C and paragraph 0046, wherein 93 is formed in 86).
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 Wang to form a height of the backside contact is larger than a height of the source/drain placeholder material by modifying the heights of 300 and 292 of 190D (Wang, Fig. 25), as taught by Lin, since the backside contact 130 (Lin, Fig. 34B, paragraph 0049) provides electrically connection between the source/drain element 92 (Lin, Fig. 34B, paragraph 0012) and the backside interconnect structure 136 (Lin, Fig. 34B, paragraph 0071).
Regarding claim 22, Wang discloses the semiconductor structure of claim 21, however Wang does not disclose the width measured at the top surface of the backside contact is substantially equal to a width of the first source drain, and wherein the width measured at a top surface of the placeholder is substantially equal to a width of the second source drain.
Lin discloses the width (horizontal length of 130 in Fig. 34B) measured at the top surface of the backside contact 130 (Fig. 34B, paragraph 0049) is substantially equal to a width (horizontal length of 92 between 81 in Fig. 34B) of the first source drain 92 (Fig. 34B, paragraph 0013), and wherein the width (horizontal length of region between 95 and 129 in Fig. 34B) measured at a top surface of the placeholder (region between 95 and 129 in Fig. 34B; and see Fig. 13C and paragraph 0046, wherein 93 is formed in 86) is substantially equal to a width (horizontal length of 95 between 81 in Fig. 34B) of the second source drain 95 (Fig. 34B, paragraph 0013).
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 Wang to form the width measured at the top surface of the backside contact is substantially equal to a width of the first source drain, and wherein the width measured at a top surface of the placeholder is substantially equal to a width of the second source drain by modifying the widths of the backside contact (Wang, 300 and 315 in Fig. 25), the first source drain (Wang, 280 and 194 of 190S in Fig. 25), the placeholder (Wang, 192 of 190D in Fig. 25), and the second source drain (Wang, 194 of 190D in Fig. 25), as taught by Lin, since the backside contact 130 (Lin, Fig. 34B, paragraph 0049) electrically connects between the source/drain element 92 (Lin, Fig. 34B, paragraph 0012) and the backside interconnect structure 136 (Lin, Fig. 34B, paragraph 0071).
Regarding claim 24, Wang discloses the semiconductor structure of claim 21, however Wang does not disclose a height of the backside contact is larger than a height of the placeholder.
Lin discloses a height of the backside contact 130 (Fig. 34B, paragraph 0049) is larger than a height of the placeholder (region between 95 and 129 in Fig. 34B; and see Fig. 13C and paragraph 0046, wherein 93 is formed in 86).
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 Wang to form a height of the backside contact is larger than a height of the placeholder by modifying the heights of 300 and 292 of 190D of Wang, as taught by Lin, since the backside contact 130 (Lin, Fig. 34B, paragraph 0049) provides electrically connection between the source/drain element 92 (Lin, Fig. 34B, paragraph 0012) and the backside interconnect structure 136 (Lin, Fig. 34B, paragraph 0071).
Regarding claim 30, Wang discloses the semiconductor structure of claim 27, however Wang does not disclose a height of the backside contact is larger than a height of the placeholder.
Lin discloses a height of the backside contact 130 (Fig. 34B, paragraph 0049) is larger than a height of the placeholder (region between 95 and 129 in Fig. 34B; and see Fig. 13C and paragraph 0046, wherein 93 is formed in 86).
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 Wang to form a height of the backside contact being larger than a height of the placeholder by modifying the heights of 300 and 292 of 190D (Wang, Fig. 25), as taught by Lin, since the backside contact 130 (Lin, Fig. 34B, paragraph 0049) provides electrically connection between the source/drain element 92 (Lin, Fig. 34B, paragraph 0012) and the backside interconnect structure 136 (Lin, Fig. 34B, paragraph 0071).
Claims 5, 25, and 31 are rejected under 35 U.S.C. 103 as being unpatentable over Wang as applied to claims 1, 21, and 27 above, and further in view of Yin et al. (US 2022/0157969) (hereafter Yin).
Regarding claim 5, Wang discloses the semiconductor device of claim 1, however Wang does not disclose the source/drain placeholder material has a diamond shape.
Yin discloses the source/drain placeholder material 238 (Fig. 20, paragraph 0029) has a diamond shape (“diamond-like shape” in paragraph 0029).
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 Wang to form the source/drain placeholder material has a diamond shape by modifying the shape of 192 of 190D (Wang, Fig. 25), as taught by Yin, since a person of ordinary skill has good reason to pursue the known options within his or her technical grasp, in the instant case choosing diamond shape from the shapes listed in Yin (e.g. a diamond-like shape, a rhombus-like shape, or a portion thereof); if this leads to the anticipated success, in the instant case providing a epitaxial layer, it is likely the product not of innovation but of ordinary skill. KSR Int'l Co. v. Teleflex Inc., 550 U.S. 398, 415-421, 82 USPQ2d 1385, 1395-97 (2007).
Regarding claim 25, Wang discloses the semiconductor structure of claim 21, however Wang does not disclose the placeholder has a diamond shape.
Yin discloses the source/drain placeholder material 238 (Fig. 20, paragraph 0029) has a diamond shape (“diamond-like shape” in paragraph 0029).
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 Wang to form the source/drain placeholder material has a diamond shape by modifying the shape of 192 of 190D (Wang, Fig. 25), as taught by Yin, since a person of ordinary skill has good reason to pursue the known options within his or her technical grasp, in the instant case choosing diamond shape from the shapes listed in Yin (e.g. a diamond-like shape, a rhombus-like shape, or a portion thereof); if this leads to the anticipated success, in the instant case providing a epitaxial layer, it is likely the product not of innovation but of ordinary skill. KSR Int'l Co. v. Teleflex Inc., 550 U.S. 398, 415-421, 82 USPQ2d 1385, 1395-97 (2007).
Regarding claim 31, Wang discloses the semiconductor structure of claim 27, however Wang does not disclose the placeholder has a diamond shape.
Yin discloses the placeholder material 238 (Fig. 20, paragraph 0029) has a diamond shape (“diamond-like shape” in paragraph 0029).
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 Wang to form the placeholder having a diamond shape by modifying the shape of 192 of 190D (Wang, Fig. 25), as taught by Yin, since a person of ordinary skill has good reason to pursue the known options within his or her technical grasp, in the instant case choosing diamond shape from the shapes listed in Yin (e.g. a diamond-like shape, a rhombus-like shape, or a portion thereof); if this leads to the anticipated success, in the instant case providing a epitaxial layer, it is likely the product not of innovation but of ordinary skill. KSR Int'l Co. v. Teleflex Inc., 550 U.S. 398, 415-421, 82 USPQ2d 1385, 1395-97 (2007).
Claim 28 is rejected under 35 U.S.C. 103 as being unpatentable over Wang as applied to claims 27 above, and further in view of Ju et al. (US 2021/0351303) (hereafter Ju).
Regarding claim 28, Wang discloses the semiconductor structure of claim 27, however Wang does not disclose a first width of the backside contact is substantially equal to a width of the first source drain, and wherein a second width of the backside contact is greater than the width of the first source drain.
Ju discloses a first width (horizontal length of top surface of 120 of 400a in Fig. 6C) of the backside contact (120 of 400a in Fig. 6C, paragraph 0027) is substantially equal to a width (horizontal length of top surface of 106 of 400a in Fig. 6C) of the first source drain (106 of 400a in Fig. 6C, paragraph 0025), and wherein a second width (horizontal length of bottom surface of 120 of 400a in Fig. 6C) of the backside contact (120 of 400a in Fig. 6C) is greater than the width (horizontal length of top surface of 106 of 400a in Fig. 6C) of the first source drain (106 of 400a in Fig. 6C).
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 Wang to form a first width of the backside contact is substantially equal to a width of the first source drain, and wherein a second width of the backside contact is greater than the width of the first source drain by modifying the widths of the backside contact (Wang, 300 and 315 in Fig. 25) and the first source drain (Wang, 280 and 194 of 190S in Fig. 25), as taught by Ju, since the first source/drain epitaxial structure 106 (Ju, Fig. 6C, paragraph 0027) can be connected to external circuits from the back side of the semiconductor transistor device 100 (Ju, Fig. 6C, paragraph 0027) through the back-side source/drain contact 120 (Ju, Fig. 6C, paragraph 0027).
Response to Arguments
1. Applicant's arguments filed 6/5/2026 have been fully considered.
2. Applicant's arguments with respect to claims 1- 7 and 21-32 have been considered but are moot in view of the new ground(s) of rejection.
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 extension fee 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 date of this final action.
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/L.B.K/Examiner, Art Unit 2813
/STEVEN B GAUTHIER/Supervisory Patent Examiner, Art Unit 2813
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