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 .
Information Disclosure Statement
The information disclosure statement (IDS) submitted on 3/1/2024 and 4/30/2025. The submission is in compliance with the provisions of 37 CFR 1.97. Accordingly, the information disclosure statement is being considered by the examiner.
Claim Rejections - 35 USC § 103
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.
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) 1-15 are rejected under 35 U.S.C. 103 as being unpatentable over Lin et al. US 2022/0216340 in view of Dewey et al. US 2023/0197569.
Re claim 1, Lin teaches a semiconductor device (200, fig20, [13]), comprising:
a stacked transistor structure having field effect transistors on at least two levels (204B and 204T, fig5 and 20, [16]), the at least two levels including a top side (204T, fig9 and 20, [16]) and bottom side (204B, fig7 and 20, [16]);
a bottom power rail (286, fig20, [38]) disposed on the bottom side on source/drain regions (228-1, fig20, [38]) of the field effect transistors; and
a top power rail (276, fig20, [37]) disposed on the top side on source/drain regions (248-1, fig20, [37]) of the field effect transistors.
Lin does not explicitly show a bottom power rail disposed on the bottom side between source/drain regions of the field effect transistors; and a top power rail disposed on the top side between source/drain regions of the field effect transistors.
Dewey teaches forming U shaped S/D contacts (236, fig2H, [50]) in S/D region.
It would have been obvious to one having ordinary skill in the art before the effective filing date of the claimed invention to combine the teaching of Lin and Dewey to form U shaped top and bottom power rail in region 228-1 and 248-1 of Lin with isolation layer 242 of Lin formed between the two power rails. The motivation to do so is to increase contact area between the power rail and the S/D region and create a more robust ohmic contact with lower contact resistance (Dewey, [9]).
Re claim 2, Lin modified above teaches the semiconductor device as recited in claim 1, wherein the bottom power rail and the top power rail are vertically disposed relative to one another (Lin, U shaped 276 formed in 248-1 and U shaped 286 in 228-1, fig20).
Re claim 3, Lin modified above teaches the semiconductor device as recited in claim 1, wherein the bottom power rail (Lin, U shaped 286 in 228-1, fig20) and the top power rail (Lin, U shaped 276 formed in 248-1, fig20) are separated by a power rail barrier (Lin, 242, fig10, 20, [25]).
Re claim 4, Lin modified above teaches the semiconductor device as recited in claim 1, wherein the bottom power rail connects to a bottom source/drain region (Lin, U shaped 286 in 228-1, fig20).
Re claim 5, Lin modified above teaches the semiconductor device as recited in claim 1, wherein the top power rail connects to a top source/drain region (Lin, U shaped 276 formed in 248-1, fig20).
Re claim 6, Lin modified above teaches the semiconductor device as recited in claim 1, wherein the bottom power rail (Lin, U shaped 286 in 228-1, fig20) and the top power rail (Lin, U shaped 276 formed in 248-1, fig20) together provide positive and negative supply voltages ("[A]pparatus claims cover what a device is, not what a device does." Hewlett-Packard Co. v. Bausch & Lomb Inc., 909 F.2d 1464, 1469, 15 USPQ2d 1525, 1528 (Fed. Cir. 1990). A claim containing a "recitation with respect to the manner in which a claimed apparatus is intended to be employed does not differentiate the claimed apparatus from a prior art apparatus" if the prior art apparatus teaches all the structural limitations of the claim. Ex parte Masham, 2 USPQ2d 1647 (Bd. Pat. App. & Inter. 1987). Lin in view of Dewey teaches the device with the same structure of the claimed device and manner of operating the device does not differentiate apparatus claim from the prior art.).
Re claim 7, Lin modified above teaches the semiconductor device as recited in claim 1, wherein the bottom power rail (Lin, U shaped 286 in 228-1, fig20) and the top power rail (Lin, U shaped 276 formed in 248-1, fig20) provide positive supply voltages ("[A]pparatus claims cover what a device is, not what a device does." Hewlett-Packard Co. v. Bausch & Lomb Inc., 909 F.2d 1464, 1469, 15 USPQ2d 1525, 1528 (Fed. Cir. 1990). A claim containing a "recitation with respect to the manner in which a claimed apparatus is intended to be employed does not differentiate the claimed apparatus from a prior art apparatus" if the prior art apparatus teaches all the structural limitations of the claim. Ex parte Masham, 2 USPQ2d 1647 (Bd. Pat. App. & Inter. 1987). Lin in view of Dewey teaches the device with the same structure of the claimed device and manner of operating the device does not differentiate apparatus claim from the prior art.).
Re claim 8, Lin modified above teaches the semiconductor device as recited in claim 1, wherein the bottom power rail (Lin, U shaped 286 in 228-1, fig20) and the top power rail (Lin, U shaped 276 formed in 248-1, fig20) provide negative supply voltages ("[A]pparatus claims cover what a device is, not what a device does." Hewlett-Packard Co. v. Bausch & Lomb Inc., 909 F.2d 1464, 1469, 15 USPQ2d 1525, 1528 (Fed. Cir. 1990). A claim containing a "recitation with respect to the manner in which a claimed apparatus is intended to be employed does not differentiate the claimed apparatus from a prior art apparatus" if the prior art apparatus teaches all the structural limitations of the claim. Ex parte Masham, 2 USPQ2d 1647 (Bd. Pat. App. & Inter. 1987). Lin in view of Dewey teaches the device with the same structure of the claimed device and manner of operating the device does not differentiate apparatus claim from the prior art.).
Re claim 9, Lin teaches a semiconductor device (200, fig20, [13]), comprising:
a stacked transistor structure having field effect transistors on at least two levels (204B and 204T, fig5 and 20, [16]), the at least two levels including a top side (204T, fig9 and 20, [16]) and bottom side (204B, fig7 and 20, [16]); and
a stacked power rail (276,286, fig20, [37, 38]) disposed between the field effect transistors on the at least two levels,
Lin does not explicitly show the stacked power rail having: a bottom power rail electrically isolated from surrounding structures by a first dielectric spacer; and a top power rail electrically isolated from surrounding structures by a second dielectric spacer.
Dewey teaches bottom power rail (246, fig2L, [56]) electrically isolated from surrounding structures by a first dielectric spacer (242, fig2L, [56]); and a top power rail (236, fig2H, [49]) electrically isolated from surrounding structures by a second dielectric spacer (234, fig2H, [49]).
It would have been obvious to one having ordinary skill in the art before the effective filing date of the claimed invention to combine the teaching of Lin and Dewey to form U shaped top and bottom power rail with dielectric spacers in region 228-1 and 248-1 of Lin and isolation layer 242 of Lin formed between the two power rails. The motivation to do so is to increase contact area between the power rail and the S/D region and create a more robust ohmic contact with lower contact resistance (Dewey, [9]).
Re claim 10, Lin modified above teaches the semiconductor device as recited in claim 9, wherein the bottom power rail (Lin, U shaped 286 in 228-1, fig20) and the top power rail (Lin, U shaped 276 formed in 248-1, fig20) are separated by a power rail barrier (Lin, 242, fig10, 20, [25]).
Re claim 11, Lin modified above teaches the semiconductor device as recited in claim 9, wherein the bottom power rail connects to a bottom source/drain region (Lin, U shaped 286 in 228-1, fig20).
Re claim 12, Lin modified above teaches the semiconductor device as recited in claim 9, wherein the top power rail connects to a top source/drain region (Lin, U shaped 276 formed in 248-1, fig20).
Re claim 13, Lin modified above teaches the semiconductor device as recited in claim 9, wherein the bottom power rail (Lin, U shaped 286 in 228-1, fig20) and the top power rail (Lin, U shaped 276 formed in 248-1, fig20) together provide positive and negative supply voltages ("[A]pparatus claims cover what a device is, not what a device does." Hewlett-Packard Co. v. Bausch & Lomb Inc., 909 F.2d 1464, 1469, 15 USPQ2d 1525, 1528 (Fed. Cir. 1990). A claim containing a "recitation with respect to the manner in which a claimed apparatus is intended to be employed does not differentiate the claimed apparatus from a prior art apparatus" if the prior art apparatus teaches all the structural limitations of the claim. Ex parte Masham, 2 USPQ2d 1647 (Bd. Pat. App. & Inter. 1987). Lin in view of Dewey teaches the device with the same structure of the claimed device and manner of operating the device does not differentiate apparatus claim from the prior art.).
Re claim 14, Lin modified above teaches the semiconductor device as recited in claim 9, wherein the bottom power rail (Lin, U shaped 286 in 228-1, fig20) and the top power rail (Lin, U shaped 276 formed in 248-1, fig20) provide positive supply voltages ("[A]pparatus claims cover what a device is, not what a device does." Hewlett-Packard Co. v. Bausch & Lomb Inc., 909 F.2d 1464, 1469, 15 USPQ2d 1525, 1528 (Fed. Cir. 1990). A claim containing a "recitation with respect to the manner in which a claimed apparatus is intended to be employed does not differentiate the claimed apparatus from a prior art apparatus" if the prior art apparatus teaches all the structural limitations of the claim. Ex parte Masham, 2 USPQ2d 1647 (Bd. Pat. App. & Inter. 1987). Lin in view of Dewey teaches the device with the same structure of the claimed device and manner of operating the device does not differentiate apparatus claim from the prior art.).
Re claim 15, Lin modified above teaches the semiconductor device as recited in claim 9, wherein the bottom power rail (Lin, U shaped 286 in 228-1, fig20) and the top power rail (Lin, U shaped 276 formed in 248-1, fig20) provide negative supply voltages ("[A]pparatus claims cover what a device is, not what a device does." Hewlett-Packard Co. v. Bausch & Lomb Inc., 909 F.2d 1464, 1469, 15 USPQ2d 1525, 1528 (Fed. Cir. 1990). A claim containing a "recitation with respect to the manner in which a claimed apparatus is intended to be employed does not differentiate the claimed apparatus from a prior art apparatus" if the prior art apparatus teaches all the structural limitations of the claim. Ex parte Masham, 2 USPQ2d 1647 (Bd. Pat. App. & Inter. 1987). Lin in view of Dewey teaches the device with the same structure of the claimed device and manner of operating the device does not differentiate apparatus claim from the prior art.).
Claim(s) 16-20 are rejected under 35 U.S.C. 103 as being unpatentable over Lin et al. US 2022/0216340 in view of Dewey et al. US 2023/0197569 and Peng et al. US 2022/0123023.
Re claim 16, Lin teaches a semiconductor device (200, fig20, [13]), comprising:
a stacked transistor structure having field effect transistors on at least two levels (204B and 204T, fig5 and 20, [16]), the at least two levels including a top side (204T, fig9 and 20, [16]) and bottom side (204B, fig7 and 20, [16]); and
a stacked power rail (276, 286, fig20, [37, 38]) disposed between the field effect transistors on the at least two levels,
a power rail barrier (242, fig10, 20, [25]) electrically separating the top power rail (276, fig20, [37, 38]) from the bottom power rail (286, fig20, [37, 38]).
Lin does not explicitly show the stacked power rail having: a bottom power rail electrically isolated from the field effect transistors and gates by a first dielectric spacer, the bottom power rail being connected to a backside power rail; a top power rail electrically isolated from the field effect transistors and gates by a second dielectric spacer, the top power rail being connected to a frontside component; and a power rail barrier connecting the first dielectric spacer and the second dielectric spacer and electrically separating the top power rail from the bottom power rail.
Dewey teaches a bottom power rail (246, fig2L, [56]) electrically isolated from the field effect transistors and gates by a first dielectric spacer (242 and part of 212 along 246, fig2L, [44, 56]); a top power rail (236, fig2H, [49]) electrically isolated from the field effect transistors and gates by a second dielectric spacer (234 and part of 212 along 236, fig2H, [44, 49]); and a power rail barrier (232, fig2G, [48]) connecting the first dielectric spacer (242 and top part of 212, fig2L, [44, 56]) and the second dielectric spacer (234 and bottom part of 212, fig2H, [44, 49]).
It would have been obvious to one having ordinary skill in the art before the effective filing date of the claimed invention to combine the teaching of Lin and Dewey to form U shaped top and bottom power rail with dielectric spacers in region 228-1 and 248-1 of Lin with isolation layer 242 of Lin formed between the two power rails. The motivation to do so is to increase contact area between the power rail and the S/D region and create a more robust ohmic contact with lower contact resistance (Dewey, [9]).
Peng teaches the bottom power rail (556 connected with S/D 113/114, fig5D, [45, 86]) being connected to a backside power rail (132, fig5D, [56]); the top power rail (556 connected with S/D 123/124, fig5D, [49, 86]) being connected to a frontside component (142, fig5D, [57).
It would have been obvious to one having ordinary skill in the art before the effective filing date of the claimed invention to combine the teaching of Lin in view of Dewey and Peng to connect the U shaped top and bottom power rail with frontside power rail 142 VDD and backside power rail 132 VSS. The motivation to do so is to effectively decrease the resistance and power consumption of the device by forming power rails with adequate line width while decreasing the distance of the conduction path (Peng, [41]).
Re claim 17, Lin modified above teaches the semiconductor device as recited in claim 16, wherein the bottom power rail connects to a bottom source/drain region (Lin, U shaped 286 in 228-1, fig20).
Re claim 18, Lin modified above teaches the semiconductor device as recited in claim 16, wherein the top power rail connects to a top source/drain region (Lin, U shaped 276 formed in 248-1, fig20).
Re claim 19, Lin modified above teaches the semiconductor device as recited in claim 16, wherein the bottom power rail (Lin, U shaped 286 in 228-1, fig20) and the top power rail (Lin, U shaped 276 formed in 248-1, fig20) together provide positive and negative supply voltages ("[A]pparatus claims cover what a device is, not what a device does." Hewlett-Packard Co. v. Bausch & Lomb Inc., 909 F.2d 1464, 1469, 15 USPQ2d 1525, 1528 (Fed. Cir. 1990). A claim containing a "recitation with respect to the manner in which a claimed apparatus is intended to be employed does not differentiate the claimed apparatus from a prior art apparatus" if the prior art apparatus teaches all the structural limitations of the claim. Ex parte Masham, 2 USPQ2d 1647 (Bd. Pat. App. & Inter. 1987). Lin in view of Dewey and Peng teaches the device with the same structure of the claimed device and manner of operating the device does not differentiate apparatus claim from the prior art.).
Re claim 20, Lin modified above teaches the semiconductor device as recited in claim 16, wherein the bottom power rail (Lin, U shaped 286 in 228-1, fig20) and the top power rail (Lin, U shaped 276 formed in 248-1, fig20) provide a same supply voltage ("[A]pparatus claims cover what a device is, not what a device does." Hewlett-Packard Co. v. Bausch & Lomb Inc., 909 F.2d 1464, 1469, 15 USPQ2d 1525, 1528 (Fed. Cir. 1990). A claim containing a "recitation with respect to the manner in which a claimed apparatus is intended to be employed does not differentiate the claimed apparatus from a prior art apparatus" if the prior art apparatus teaches all the structural limitations of the claim. Ex parte Masham, 2 USPQ2d 1647 (Bd. Pat. App. & Inter. 1987). Lin in view of Dewey and Peng teaches the device with the same structure of the claimed device and manner of operating the device does not differentiate apparatus claim from the prior art.).
Conclusion
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/XIAOMING LIU/Examiner, Art Unit 2812
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