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 1-3, 5-8 are rejected under 35 U.S.C. 103 as being unpatentable over Cheng et al (US Patent No. 9,899,441) in view of Tang et al (US Publication No. 2023/0253207) and Yang et al (US Publication No. 2022/0367620).
Regarding claim 1, Cheng discloses a method of forming a semiconductor device, comprising: providing a substrate Fig 4, 108 having a recess Fig 4; and growing an epitaxial feature in the recess (Column 9, lines 7-44), wherein the growing comprises:(a) growing a sub-layer of the epitaxial feature Fig 6, 118;(b) selectively etching the sub-layer of the epitaxial feature (Column 10, line 52-Column 12, line 2); and(c) repeating step (a) and step (b) alternately multiple times (Column 12, lines 35-53). Cheng discloses all the limitations but silent on the UV radiation. Whereas Tang discloses a method of forming a semiconductor device, comprising providing a substrate Fig 2, 12 having a recess Fig 2; and growing an epitaxial feature in the recess, wherein the growing comprises:(a) growing a sub-layer of the epitaxial feature Fig 3;(b) selectively etching the sub-layer of the epitaxial feature while providing a first UV radiation Fig 4 ¶0028, 0033-0039. Cheng and Tang are analogous art because they are directed to semiconductor devices having epi source and drain regions and one of ordinary skill in the art would have had a reasonable expectation of success to modify Cheng because they are from the same field of endeavor. Therefore, it would have been obvious to one having ordinary skill of the art before the effective filing date of the claimed invention to modify the process of Cheng and incorporate the teachings of Tang to improve manufacturing process and film uniformity ¶0002. Cheng and Tang discloses all the limitations but silent on the shape/arrangement of the epitaxial feature. Whereas Yang discloses a sublayer of the epitaxial feature is discontinuous Fig 2E ¶0024.
Cheng and Yang are analogous art because they are directed to semiconductor devices having epi regions and one of ordinary skill in the art would have had a reasonable expectation of success to modify Cheng because they are from the same field of endeavor. Therefore, it would have been obvious to one having ordinary skill of the art before the effective filing date of the claimed invention to modify the process of Cheng and incorporate the teachings of Yang to since such a modification would have involved a mere change in the shape of a component. A change in shape is generally recognized as being within the level of ordinary skill in the art. In reDailey, 357 F.2d 669, 149 USPQ 47 (CCPA 1966).
Regarding claim 2, Tang discloses wherein the first UV radiation is provided at a direction normal to a top surface of the substrate Fig 4.
Regarding claim 3, Cheng discloses wherein an upper portion of the sub-layer of the epitaxial feature is etched more than a lower portion of the sub- layer of the epitaxial feature in step (b) (Column 12, lines 35-53).
Regarding claim 5, Cheng in view of Tang discloses wherein the growing further comprises:(d) selectively growing the epitaxial feature in a z-direction while providing a second UV radiation after step (c) (Column 12, lines 35-53).
Regarding claim 6, Tang discloses wherein the second UV radiation is provided at a direction normal to a top surface of the substrate Fig 4.
Regarding claim 7, Cheng discloses wherein after step (d), a top width of the epitaxial feature is substantially equal to or greater than a bottom width of the epitaxial feature Fig 3A.
Regarding claim 8, Cheng discloses forming a liner layer between the substrate and the epitaxial feature Fig 3A.
Claim 4 is rejected under 35 U.S.C. 103 as being unpatentable over Cheng et al (US Patent No. 9,899,441) in view of Tang et al (US Publication No. 2023/0253207) and Yang et al (US Publication No. 2022/0367620) and in further view of Huang (US Publication No. 2019/0371898).
Regarding claim 4, Cheng discloses all the limitations but silent on the shape of the epitaxial structure. Whereas Huang discloses wherein after step (c), a top width of the epitaxial feature is less than a bottom width of the epitaxial feature Fig 14. Cheng and Huang are analogous art because they are directed to semiconductor devices having epi source and drain regions and one of ordinary skill in the art would have had a reasonable expectation of success to modify Cheng because they are from the same field of endeavor. Therefore, it would have been obvious to one having ordinary skill of the art before the effective filing date of the claimed invention to modify the shape of the source and drain of Cheng and incorporate the teachings of Huang since such a modification would have involved a mere change in the shape of a component. A change in shape is generally recognized as being within the level of ordinary skill in the art. In reDailey, 357 F.2d 669, 149 USPQ 47 (CCPA 1966).
Claims 19-20 are rejected under 35 U.S.C. 103 as being unpatentable over Xie et al (US Patent No. 11,211,452) in view of Tang et al (US Publication No. 2023/0253207) and Cheng et al (US Patent No. 9,899,441) and in further view of Yang et al (US Publication No. 2022/0367620).
Regarding claim 19, Xie discloses a method of forming a semiconductor device, comprising: forming semiconductor strips on a substrate Fig 1; forming a dummy gate stack across the semiconductor strips Fig 2; removing portions of the semiconductor strips at opposite sides of the dummy gate stack to form recesses exposing the substrate forming an epitaxial feature in each of the recesses Fig 3-4, wherein the forming comprises:(a) growing a sub-layer of the epitaxial layer in each of the recesses Fig 7-8. Xie discloses all the limitations but silent on the deposition process with UV radiation. Whereas Tang discloses a method of forming a semiconductor device, comprising providing a substrate Fig 2, 12 having a recess Fig 2; and growing an epitaxial feature in the recess, wherein the growing comprises:(a) growing a sub-layer of the epitaxial feature Fig 3;(b) selectively etching the sub-layer of the epitaxial feature while providing a first UV radiation Fig 4 ¶0028, 0033-0039. Xie and Tang are analogous art because they are directed to semiconductor devices having epi source and drain regions and one of ordinary skill in the art would have had a reasonable expectation of success to modify Xie because they are from the same field of endeavor. Therefore it would have been obvious to one having ordinary skill of the art before the effective filing date of the claimed invention to modify the process of Xie and incorporate the teachings of Tang as an alternative process to improve manufacturing process and film uniformity ¶0002. Xie and Tang are silent on the frequency. Whereas Cheng discloses a method of forming a semiconductor device, comprising: providing a substrate Fig 4, 108 having a recess Fig 4; and growing an epitaxial feature in the recess (Column 9, lines 7-44), wherein the growing comprises:(a) growing a sub-layer of the epitaxial feature Fig 6, 118;(b) selectively etching/removing the sub-layer of the epitaxial feature (Column 10, line 52-Column 12, line 2); and(c) repeating step (a) and step (b) alternately multiple times until each of the recesses is filled with the sub-layers (Column 12, lines 35-53). Xie and Cheng are analogous art because they are directed to semiconductor devices having epi source and drain regions and one of ordinary skill in the art would have had a reasonable expectation of success to modify Xie because they are from the same field of endeavor. Therefore it would have been obvious to one having ordinary skill of the art before the effective filing date of the claimed invention to modify the process of Xie and incorporate the teachings of Cheng to improve manufacturing process. Xie, Cheng and Tang discloses all the limitations but silent on the shape/arrangement of the epitaxial feature. Whereas Yang discloses a sublayer of the epitaxial feature is discontinuous Fig 2E ¶0024. Xie, Cheng and Yang are analogous art because they are directed to semiconductor devices having epi regions and one of ordinary skill in the art would have had a reasonable expectation of success to modify Cheng because they are from the same field of endeavor. Therefore, it would have been obvious to one having ordinary skill of the art before the effective filing date of the claimed invention to modify the process of Cheng and incorporate the teachings of Yang to since such a modification would have involved a mere change in the shape of a component. A change in shape is generally recognized as being within the level of ordinary skill in the art. In reDailey, 357 F.2d 669, 149 USPQ 47 (CCPA 1966).
Regarding claim 20, Cheng in view of Tang discloses wherein the growing further comprises:(d) selectively growing the epitaxial feature in a z-direction while providing a second UV radiation after step (c) (Column 12, lines 35-53).
Allowable Subject Matter
Claims 9-18 are allowed over the prior art of record.
The following is a statement of reasons for the indication of allowable subject matter: After further search and consideration of Applicant’s response, it is determined that the prior art of record neither anticipates nor renders obvious the claimed subject matter of the instant application as a whole either taken alone or in combination, in particular, prior art of record does not teach or suggest “removing portions of the semiconductor strips at opposite sides of each of the first dummy gate stack and the second dummy gate stack to form recesses exposing the substrate, wherein each of the semiconductor strips at least comprises a first channel layer and a second channel layer stacked alternately; and forming an epitaxial feature from each of the recesses by performing a cyclic deposition and etching process with UV illumination, wherein the cyclic deposition and etching process comprises:(a) growing a sub-layer of the epitaxial feature in each of the recesses; and (b) selectively etching the sub-layer of the epitaxial feature while providing a first UV radiation, wherein the sub-layer interfacing the first and second channel layers is exposed to the first UV radiation”, as recited in independent claim 9.
Claims 10-18 are also allowed as being directly or indirectly dependent of the allowed independent base claims.
Response to Arguments
Applicant’s arguments with respect to claims 1-20 have been considered but are moot because the new ground of rejection does not rely on any reference applied in the prior rejection of record for any teaching or matter specifically challenged in the argument.
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 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.
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/CHRISTINE A ENAD/Primary Examiner, Art Unit 2811
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