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 .
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 1, 4-8, and 10-11 are rejected under 35 U.S.C. 103 as being unpatentable over Motoyama et al. (US 20190348278 A1) hereinafter “Motoyama” in view of Chang et al. (US 20220130979 A1) hereinafter “Chang,” Manabe (US 20130307082 A1) hereinafter “Manabe” Cheng et al. (US 20190172723 A1) hereinafter “Cheng,” and Yu et al. (US 5869384 A) hereinafter “Yu.”.
Regarding Claim 1, Figures 1A-1G of Motoyama teach: A method for manufacturing a semiconductor device (Figures 1A-1G), the method comprising: providing a substrate (101) covered with a silicon dioxide film (103); forming a silicon seed layer (Not pictured; Paragraph 0017) on the silicon dioxide film; depositing a silicon film (104) onto a recess (102a) provided in a surface of the substrate by supplying a silicon-containing gas to the substrate (Paragraph 0017), the recess having a bottom surface (102b) and sidewall surfaces (102s) extending upward from edges of the bottom surface, the sidewall surfaces including a lower portion (lower portion vertically of 102s) directly connected to the bottom surface of the recess and an upper portion (upper portion vertically of 102s) directly connected to the surface of the substrate; etching the substrate by supplying an etching gas (Figure 1C; Paragraph 0018) to the substrate to leave the silicon film on the bottom surface of the recess (Figure 1C) and completely removing the silicon film and the seed layer from an area including the upper portion of the sidewall surfaces and the top surface of the substrate (Figure 1C), thereby exposing the silicon dioxide film in the area (Figure 1C); and supplying dichlorosilane gas (Paragraph 0019) to the substrate, thereby selectively growing a silicon film (107) upwards from the amorphous silicon film remaining at the bottom surface of the recess
Motoyama does not explicitly teach: depositing an amorphous silicon film onto a recess
Figure 8 of Chang teaches: depositing an amorphous silicon film (Paragraph 0030; 60) onto a recess (55)
It would be obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to have the first silicon film be an amorphous silicon film because amorphous silicon films are used as a seed layer to aid in gap-filling trenches (Chang Paragraph 0030)
Motoyama does not teach: the silicon film deposited on the amorphous silicon film is a polysilicon film.
Figure 8 of Manabe teaches: a polysilicon fill layer (26) in trench (20)
It would be obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to have the silicon film deposited on the amorphous silicon film be a polysilicon film because polysilicon has good step coverage and gap fill characteristics than metals, making the polysilicon less prone to voids (Manabe Paragraph 0049).
Motoyama does not teach: the polysilicon film being crystallized during the selective growth
However, polysilicon has the inherent property of being a crystalline material, therefore it would have been obvious to one of ordinary skill in the art that the polysilicon film is crystallized during the selective growth.
Motoyama does not teach: annealing the substrate after the selective growth
Figure 3 of Cheng teaches: a post-process (260) of filling a feature (110; Figure 1) comprising an anneal (paragraph 0046)
It would be obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to anneal the substrate after the selective growth because Cheng teaches a post-process anneal can be used to modify the treated film to improve some parameter of the film (Cheng Paragraph 0046).
Motoyama does not teach: the polysilicon film maintains a crystalline state without shrinkage during the annealing
Table II of Yu teaches: measurements of shrinkage that occurs in polysilicon after an O2 anneal is 0.8%.
It would be obvious to one of ordinary skill in the art before the effective filing date of the claimed invention that the polycrystalline film will maintain a crystalline state without shrinkage during the annealing because Yu teaches polysilicon yielded comparatively little shrinkage upon thermal annealing within an oxygen containing atmosphere (Yu C11/L18-23).
Regarding Claim 4, Figures 1A-1G of Motoyama teach: the step of etching the silicon film (104) is performed by supplying the etching gas (Paragraph 0018) in a supply limited mode (Paragraph 0040; flow rates are controlled) so as not to completely etch the amorphous silicon film up to the bottom surface of the recess (Paragraph 0018).
Regarding Claim 5, Figures 1A-1G of Motoyama teach: the supply limited mode is performed by controlling a flow rate (Paragraph 0040)
Regarding Claim 6, Figures 1A-1G of Motoyama teach: the etching gas is chlorine (Paragraph 0018).
Regarding Claim 7, Figures 1A-1G of Motoyama teach: the step of depositing the silicon film (104) in the recess comprises supplying monosilane or disilane (Paragraph 0017; SiH4, Si2H6).
Regarding Claim 8, Figures 1A-1G of Motoyama teach: depositing the silicon film (104) in the recess (102a) such that a width of an opening formed by opposing sides of the silicon film is formed (Paragraph 0017) so as to hinder the etching gas from passing the opening in a range of not blocking the opening formed by the opposing sides of the silicon film (Paragraph 0018).
Regarding Claim 10, Figures 1A-1G of Motoyama teach: the silicon film (107) on the silicon film (104) is performed until the silicon film fills the recess (Figure 1G)
Regarding Claim 11, Figures 1A-2 of Motoyama teach: A substrate processing apparatus (1; Figure 2), comprising: a processing chamber (34); a substrate holding member (38) disposed in the processing chamber and configured to hold (Paragraph 0031) a substrate (101) having a recess (102a) in a surface of the substrate, the substrate being covered with a silicon dioxide film (103); a seed layer forming part (Paragraph 0031) configured to form a silicon seed layer (Not pictured; Paragraph 0017) on the silicon dioxide film; a silicon-containing gas supply part (Paragraph 0040) configured to supply a silicon-containing gas (Paragraph 0017) and to deposit a silicon film (104) onto the recess, the recess having a bottom surface (102b) and sidewall surfaces (102s) extending upward from edges of the bottom surface, the sidewall surfaces including a lower portion (lower portion vertically of 102s) directly connected to the bottom surface of the recess and an upper portion (upper portion vertically of 102s) directly connected to the surface of the substrate; an etching gas supply part (Paragraph 0040) configured to supply an etching gas (Paragraph 0018) to the substrate to leave the silicon film on the bottom surface of the recess (Figure 1C), and to completely remove the silicon film and the seed layer underlying the silicon film from an area including the upper portion of the sidewall surfaces and the top surface of the substrate (Figure 1C), thereby exposing the silicon dioxide film in the area; a dichlorosilane supply part (Paragraph 0040) configured to supply dichlorosilane gas (Paragraph 0019) to the substrate, thereby selectively growing a silicon film (107) upwards from the silicon film remaining at the bottom surface of the recess; and a heating part (42) configured to anneal the substrate
Motoyama does not explicitly teach: depositing an amorphous silicon film onto a recess
Figure 8 of Chang teaches: depositing an amorphous silicon film (Paragraph 0030; 60) onto a recess (55)
It would be obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to have the first silicon film be an amorphous silicon film because amorphous silicon films are used as a seed layer to aid in gap-filling trenches (Chang Paragraph 0030)
Motoyama does not teach: the silicon film deposited on the amorphous silicon film is a polysilicon film.
Figure 8 of Manabe teaches: a polysilicon fill layer (26) in trench (20)
It would be obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to have the silicon film deposited on the amorphous silicon film be a polysilicon film because polysilicon has good step coverage and gap fill characteristics than metals, making the polysilicon less prone to voids (Manabe Paragraph 0049).
Motoyama does not teach: the polysilicon film being crystallized during the selective growth
However, polysilicon has the inherent property of being a crystalline material, therefore it would have been obvious to one of ordinary skill in the art that the polysilicon film is crystallized during the selective growth.
Motoyama does not teach: annealing the substrate after the selective growth
Figure 3 of Cheng teaches: a post-process (260) of filling a feature (110; Figure 1) comprising an anneal (paragraph 0046)
It would be obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to anneal the substrate after the selective growth because Cheng teaches a post-process anneal can be used to modify the treated film to improve some parameter of the film (Cheng Paragraph 0046).
Motoyama does not teach: the polysilicon film maintains a crystalline state without shrinkage during the annealing
Table II of Yu teaches: measurements of shrinkage that occurs in polysilicon after an O2 anneal is 0.8%.
It would be obvious to one of ordinary skill in the art before the effective filing date of the claimed invention that the polycrystalline film will maintain a crystalline state without shrinkage during the annealing because Yu teaches polysilicon yielded comparatively little shrinkage upon thermal annealing within an oxygen containing atmosphere (Yu C11/L18-23).
Response to Arguments
Applicant's arguments filed 01/26/2026 have been fully considered but they are not persuasive.
Regarding Claim 1, and similarly Claim 11, the Applicant argues that the combination of Motoyama, Chang, Manabe, Cheng, and Yu do not teach depositing an amorphous silicon film onto a recess and selectively growing a polysilicon film upward from the amorphous silicon film remaining at the bottom surface of the recess. The Examiner respectfully disagrees and asserts that the combination of Motoyama, Chang, Manabe, Cheng, and Yu does teach depositing an amorphous silicon film onto a recess and selectively growing a polysilicon film upward from the amorphous silicon film remaining at the bottom surface of the recess. In the 35 U.S.C. 103 rejection of Claim 1 above, Figures 1A-1G of Motoyama teach a method of depositing a silicon film (104) onto a recess (102a) and selectively growing a silicon film (107) from the silicon film (104) remaining at the bottom surface of the recess after an etch. While Motoyama does not teach depositing an amorphous film into the recess, Figure 8 of Chang teaches it would be obvious to one of ordinary skill in the art to use an amorphous silicon film (60) because amorphous silicon films used as seed layers to beneficially aid in gap-filling trenches (Chang Paragraph 0030). Also, while Motoyama does not teach that the silicon film selectively grown from the amorphous silicon film remaining at the bottom surface of the recess is polysilicon, Figure 8 of Manabe teaches that it would be obvious to one of ordinary skill in the art that a polysilicon film is selectively grown because polysilicon beneficially has good step coverage and gap fill characteristics (Manabe Paragraph 0049). Hence, the combination of the method of Motoyama, with the amorphous silicon of Chang and the polysilicon of Manabe, would yield a structure such that an amorphous silicon film is deposited onto a recess and a polysilicon film is selectively grown upward from the amorphous silicon film remaining at the bottom surface of the recess. Therefore, the Examiner does not find the Applicant’s arguments to be persuasive, and will continue to rely upon the combination of Motoyama, Chang, Manabe, Cheng, and Yu to teach the claim limitations of Claim 1.
Conclusion
THIS ACTION IS MADE FINAL. 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.
Any inquiry concerning this communication or earlier communications from the examiner should be directed to Halee Cramer whose telephone number is (571)270-1641. The examiner can normally be reached Monday - Friday 7:30am - 4:30pm.
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/HALEE CRAMER/Examiner, Art Unit 2891
/MATTHEW C LANDAU/Supervisory Patent Examiner, Art Unit 2891
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