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 .
Claims 1-20 are pending
Claims 15-20 are withdrawn due to restriction
Claims 1, 6, 8, 15, 16 and 19 have been amended
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.
The factual inquiries for establishing a background for determining obviousness under 35 U.S.C. 103 are summarized as follows:
1. Determining the scope and contents of the prior art.
2. Ascertaining the differences between the prior art and the claims at issue.
3. Resolving the level of ordinary skill in the pertinent art.
4. Considering objective evidence present in the application indicating obviousness or nonobviousness.
This application currently names joint inventors. In considering patentability of the claims the examiner presumes that the subject matter of the various claims was commonly owned as of the effective filing date of the claimed invention(s) absent any evidence to the contrary. Applicant is advised of the obligation under 37 CFR 1.56 to point out the inventor and effective filing dates of each claim that was not commonly owned as of the effective filing date of the later invention in order for the examiner to consider the applicability of 35 U.S.C. 102(b)(2)(C) for any potential 35 U.S.C. 102(a)(2) prior art against the later invention.
Claim(s) 1 and 6-7 are rejected under 35 U.S.C. 103 as being unpatentable over Iwasaki et al. US 2022/0267909 (US’909) in view of Siefering et al. US 2002/0160606 (US’606).
Regarding claim 1, US’909 teaches a method of processing a substrate (a substrate processing method, abstract), comprising:
positioning a substrate within a processing chamber (a substrate is processed in processing unit 2, see fig. 2, para. 65-75);
flowing a process gas comprising hydrogen into the processing chamber (etching gas etches a metal oxide layer, the etching gas is a mixed gas of steam (H2O) and a reactive gas, such as ammonia, HCL or H2S para. 11, 85-90);
delivering energy to the process gas (overheated steam which is sufficiently heated, that is, heated at 100° C. or higher is preferably used as steam, para. 85, overheating the steam would require delivering energy to the process gas),
wherein delivering the energy to the process gas does not generate a plasma in the processing chamber (the process of US’909 does not involving plasma), and
wherein a substrate temperature is maintained at a temperature below approximately 300°C while the flowing the process gas and the delivering the energy (etching is performed when the substrate is at a temperature of 25° C. or higher and 100° C. or lower, para. 24); and
the flowing the process gas and the delivering energy removes a metal oxide from the surface of the substrate (a metal oxide is etched by the etching gas, para. 23-24 and 32-40).
US’909 does not teach the processing chamber comprises a microwave source and the energy is microwave energy.
US’606 teaches a method for removing a material from a surface of an in-process, microelectronic substrate is provided. The method comprises providing a material-removing composition in the form of a liquid and flash vaporizing the liquid, thereby forming a material-removing vapor (abstract). The Heating of the material-removing liquid may optionally be accomplished by flowing the liquid onto, across, through, or sufficiently close to a heated member, such as a hot plate or another hot surface, such that the temperature of the material-removing liquid is raised above its boiling temperature (at a given pressure, e.g., at atmospheric or non-atmospheric pressure). Rather than or in addition to using a heated member, the material-removing liquid could be "heat-flashed" by delivering microwave energy to the conduit or chamber (para. 25). The present invention provides better control of the content of the vapor to be delivered to the substrate (para. 11-18). Therefore, the method of US’606 can be combined with the method of US’909 because they are both related to providing overheated vapor/steam to a substrate to perform etching and US’606 establishes that flash vaporization of a liquid for processing a microelectronics substrate by providing microwave energy to a conduit or chamber is a known method to provide the overheated steam of US’909 by providing microwave energy to the conduits or processing unit of US’909 and can provide the benefit of better control of the content of the vapor to be delivered to the substrate.
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 method of US’909 to include the processing chamber that comprises a microwave source and the energy is microwave energy because US’606 teaches provide the overheated steam of US’909 by providing microwave energy to the conduits or processing unit of US’909 and can provide the benefit of better control of the content of the vapor to be delivered to the substrate and combining prior art elements according to known methods to yield predictable results is obvious, see MPEP 2141 III (A).
Regarding claims 6 and 7, the modified method of US’909 teaches the method of processing a semiconductor substrate of claim 1. US’909 further teaches wherein the microwave energy excites the process gas and removes contaminants from the surface of the substrate, with regard to claim 6 and wherein the contaminants include metal oxides, with regard to claim 7 (the process of US’909 forms a metal oxide layer which needs to be removed to perform atomic layer etching of a metal layer, as discussed above, see para. 2-29, therefore the heater gas of the modified method of US’909 remove the metal oxide contaminant).
Claim(s) 2 is rejected under 35 U.S.C. 103 as being unpatentable over US’909 in view of US’606 as applied to claim 1 above, and further in view of Blackwell et al. US 2020/0395223 (US’223).
Regarding claim 2, the modified method of US’909 teaches the method of processing a semiconductor substrate of claim 1.
The modified method of US’909 does not teach performing a deposition process on the substrate to form one or more metal layers over the substrate after delivering the microwave energy to the process gas.
US’223 teaches selective etching and controlled atomic layer etching of transition metal oxide films for device fabrication. The device fabrication includes performing atomic layer etching of a metal oxide followed by depositing a conductive metal via (para. 42-74, see. Fig. 4-7). Therefore, the atomic layer etching process of US’909 can be combined with the device manufacturing of US’223 in a predictable method of combining well known semiconductor manufacturing techniques to achieve predictable results.
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 modified method of US’909 to include performing a deposition process on the substrate to form one or more metal layers over the substrate after delivering the microwave energy to the process gas because US’223 teaches it is well known to perform metal deposition after metal oxide atomic layer etching when manufacturing semiconductor devices and combining prior art elements according to known methods to yield predictable results is obvious, see MPEP 2141 III (A).
Claim(s) 3-5 are rejected under 35 U.S.C. 103 as being unpatentable over US’909 in view of US’606 as applied to claim 1 above, and further in view of Blackwell et al. US 2020/0395223 (US’223) and Cen et al. US 2020/0303250 (US’250).
Regarding claims 3-5, the modified method of US’909 teaches the method of processing a semiconductor substrate of claim 1.
The modified method of US’909 does not teaches before positioning the substrate within the processing chamber, exposing the substrate to a carbon removing pretreatment process, with regard to claim 3, wherein the carbon removing pretreatment process includes delivering hydrogen radicals to the substrate using a remote plasma source, with regard to claim 4 and wherein exposing the substrate to the carbon removing pretreatment process occurs in a first chamber that does not comprise the microwave source, with regard to claim 5.
US’223 teaches that atomic layer etching is performed after filling a trench with a metal as discussed above, with regard to claim 2, and US’250 teaches performing a pre-clean process to remove contaminants, such as metal oxide, fluoride, carbon, polymer, or other post etch process residue at the bottom of the trench before filling the trench with a metal (para. 17-24). The preclean process includes generating hydrogen radicals in a remote plasma. Therefore, it is well known in the semiconductor process art to perform the combination of process steps recited in claims 3-5.
would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to modify the modified method of US’909 to include before positioning the substrate within the processing chamber, exposing the substrate to a carbon removing pretreatment process, with regard to claim 3, wherein the carbon removing pretreatment process includes delivering hydrogen radicals to the substrate using a remote plasma source, with regard to claim 4 and wherein exposing the substrate to the carbon removing pretreatment process occurs in a first chamber that does not comprise the microwave source, with regard to claim 5 because US’223 and US’250 teaches they are well known in the semiconductor process art and combining prior art elements according to known methods to yield predictable results is obvious, see MPEP 2141 III (A).
Claim(s) 8 and 13-14 are rejected under 35 U.S.C. 103 as being unpatentable over Iwasaki et al. US 2022/0267909 (US’909) in view of Siefering et al. US 2002/0160606 (US’606).
Regarding claim 8, US’909 teaches a method of processing a semiconductor structure formed in a substrate (a substrate processing method, abstract), comprising:
exposing a feature formed within a substrate to a preclean process, wherein the preclean process comprises: positioning a substrate within a processing chamber (a substrate is processed in processing unit 2 to remove layers a metal, see fig. 2, para. 2-8 and 65-75);
flowing a process gas comprising hydrogen into the processing chamber (etching gas etches a metal oxide layer, the etching gas is a mixed gas of steam (H2O) and a reactive gas, such as ammonia, HCL or H2S para. 11, 85-90);
delivering energy, from an energy source, to the process gas (overheated steam which is sufficiently heated, that is, heated at 100° C or higher is preferably used as steam, para. 85, overheating the steam would require delivering energy to the process gas),
wherein delivering the energy to the process gas does not generate a plasma in the processing chamber (the process of US’909 does not involving plasma), and
and maintaining the substrate at a temperature below 300°C (etching is performed when the substrate is at a temperature of 25° C. or higher and 100° C. or lower, para. 24).
US’909 does not teach the processing chamber comprises a microwave source and the energy is microwave energy.
US’606 teaches a method for removing a material from a surface of an in-process, microelectronic substrate is provided. The method comprises providing a material-removing composition in the form of a liquid and flash vaporizing the liquid, thereby forming a material-removing vapor (abstract). The Heating of the material-removing liquid may optionally be accomplished by flowing the liquid onto, across, through, or sufficiently close to a heated member, such as a hot plate or another hot surface, such that the temperature of the material-removing liquid is raised above its boiling temperature (at a given pressure, e.g., at atmospheric or non-atmospheric pressure). Rather than or in addition to using a heated member, the material-removing liquid could be "heat-flashed" by delivering microwave energy to the conduit or chamber (para. 25). The present invention provides better control of the content of the vapor to be delivered to the substrate (para. 11-18). Therefore, the method of US’606 can be combined with the method of US’909 because they are both related to providing overheated vapor/steam to a substrate to perform etching and US’606 establishes that flash vaporization of a liquid for processing a microelectronics substrate by providing microwave energy to a conduit or chamber is a known method to provide the overheated steam of US’909 by providing microwave energy to the conduits or processing unit of US’909 and can provide the benefit of better control of the content of the vapor to be delivered to the substrate.
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 method of US’909 to include the processing chamber that comprises a microwave source and the energy is microwave energy because US’606 teaches provide the overheated steam of US’909 by providing microwave energy to the conduits or processing unit of US’909 and can provide the benefit of better control of the content of the vapor to be delivered to the substrate and combining prior art elements according to known methods to yield predictable results is obvious, see MPEP 2141 III (A).
Regarding claims 13 and 14, the modified method of US’909 teaches the method of processing a semiconductor substrate of claim 8. US’909 further teaches wherein the microwave energy excites the process gas and removes contaminants from a surface of the feature, with regard to claim 13 and wherein the contaminants include metal oxides, with regard to claim 14 (the process of US’909 forms a metal oxide layer which needs to be removed to perform atomic layer etching of a metal layer, as discussed above, see para. 2-29, therefore the heater gas of the modified method of US’909 remove the metal oxide contaminant).
Claim(s) 9 is rejected under 35 U.S.C. 103 as being unpatentable over US’909 in view of US’606 as applied to claim 8 above, and further in view of Blackwell et al. US 2020/0395223 (US’223).
Regarding claim 9, the modified method of US’909 teaches the method of processing a semiconductor substrate of claim 8.
The modified method of US’909 does not teach performing a deposition process on the feature to form one or more metal layers after exposing the feature to the preclean process.
US’223 teaches selective etching and controlled atomic layer etching of transition metal oxide films for device fabrication. The device fabrication includes performing atomic layer etching of a metal oxide followed by depositing a conductive metal via (para. 42-74, see. Fig. 4-7). Therefore, the atomic layer etching process of US’909 can be combined with the device manufacturing of US’223 in a predictable method of combining well known semiconductor manufacturing techniques to achieve predictable results.
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 modified method of US’909 to include performing a deposition process on the feature to form one or more metal layers after exposing the feature to the preclean process because US’223 teaches it is well known to perform metal deposition after metal oxide atomic layer etching when manufacturing semiconductor devices and combining prior art elements according to known methods to yield predictable results is obvious, see MPEP 2141 III (A).
Claim(s) 10-12 are rejected under 35 U.S.C. 103 as being unpatentable over US’909 in view of US’606 as applied to claim 8 above, and further in view of Blackwell et al. US 2020/0395223 (US’223) and Cen et al. US 2020/0303250 (US’250).
Regarding claims 10-12, the modified method of US’909 teaches the method of processing a semiconductor substrate of claim 8.
The modified method of US’909 does not teaches before exposing the feature to the preclean process, exposing the feature to a carbon removing pretreatment process, with regard to claim 10, wherein the carbon removing pretreatment process includes delivering hydrogen radicals to the substrate using a remote plasma source, with regard to claim 11 and wherein exposing the substrate to the carbon removing pretreatment process occurs in a first chamber that does not comprise the microwave source, with regard to claim 12.
US’223 teaches that atomic layer etching is performed after filling a trench with a metal as discussed above, with regard to claim 9, and US’250 teaches performing a pre-clean process to remove contaminants, such as metal oxide, fluoride, carbon, polymer, or other post etch process residue at the bottom of the trench before filling the trench with a metal (para. 17-24). The preclean process includes generating hydrogen radicals in a remote plasma. Therefore, it is well known in the semiconductor process art to perform the combination of process steps recited in claims 10-12.
would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to modify the modified method of US’909 to include before exposing the feature to the preclean process, exposing the feature to a carbon removing pretreatment process, with regard to claim 10, wherein the carbon removing pretreatment process includes delivering hydrogen radicals to the substrate using a remote plasma source, with regard to claim 11 and wherein exposing the substrate to the carbon removing pretreatment process occurs in a first chamber that does not comprise the microwave source, with regard to claim 12 because US’223 and US’250 teaches they are well known in the semiconductor process art and combining prior art elements according to known methods to yield predictable results is obvious, see MPEP 2141 III (A).
Response to Amendment
Applicants’ amendments overcome the claims objections for claims 1 and 8 and 112 rejection of claims 6-7. Therefore, the objections to claim 1 and 8 and 112 rejection of claims 6-7 are withdrawn.
Response to Arguments
Applicant's arguments filed 2-13-26 have been fully considered but they are not persuasive.
Applicants’ arguments that that one of ordinary skill in the art would not combine the references as asserted because modifying the method of Iwasaki with the teachings of Siefereng would change the principle of operation of Iwasaki rendering it inoperable for its intended purpose because the proposed modification would disrupt and eliminate the mechanism by which Iwasaki achieves the controlled low-temperature etching process, has been considered but is not deemed persuasive. US’909 requires a heated etching gas, not a “cooled, low-energy vapor” and expressly teaches that “overheated steam which is sufficiently heated, that is, heated at 100°C. or higher is preferably used as steam” (para. 85). The principle of operation in US’909 is not that the supplied vapor be low-energy; it is that the substrate be maintained at a temperature lower than the supplied etching vapor (para. 21-22, 42, 170), creating a temperature differential. It is the substrate temperature adjustment (25-100°C, para. 24, 172) that “lowers” the etching fluid temperature “in the vicinity of the principal substrate”, not the supply temperature itself. Substituting microwave heating for whatever conventional heating mechanism US’909 uses to produce the overheated steam does not alter this differential and does not change the principle of operation. The substrate continues to be held at a lower temperature than the incoming vapor, and the molecular kinetic energy still decreases as molecules approach the cooled substrate.
US’606 describes microwave energy as one of several interchangeable known techniques for heat-flashing a liquid listed alongside hot plate, heated gas injection, and infrared/radiative heaters (para. 25, 51). US’606 does not characterize microwave heating as inherently hotter, more energetic, or otherwise different than the vapor produced by a hot plate or other conventional heating methods. Applicant’s assertion that microwave vaporization yields a uniquely “superheated” vapor in not a teaching of US’606; it is attorney argument unsupported by the reference. US’606 in fact identifies improved vapor composition control as the benefit of its flash-vaporization approach (para. 11-18, 21), and says nothing about producing vapor incompatible with downstream low-temperature substrate processing.
Neither US’909 nor US’606 criticize, discredit, or otherwise discourage the proposed modification. US’909 does not state that its overheated steam must be generated by any particular heating mechanism, nor that microwave heating would be unsuitable. US’606 does not state that its microwave-heated vapor is unsuitable for low-temperature substrate etching, rather, US’606 is directed to microelectronic substrate processing and expressly contemplates flash vaporization for delivering etching vapor to a substrate (abstract, para. 11-18, 47). The references are in the same field of art, substrate etching, and are directed to the same general purpose of delivering controlled etching vapor to a microelectronics substrate.
The test for obviousness is not whether the features of a secondary reference may be bodily incorporated into the structure of the primary reference; nor is it that the claimed invention must be expressly suggested in any one or all of the references. Rather, the test is what the combined teachings of the references would have suggested to those of ordinary skill in the art. See In re Keller, 642 F.2d 413, 208 USPQ 871 (CCPA 1981). The purposed combination does not require importing US’606’s pressure-drop scheme, vacuum chamber, or any operational parameter that would alter US’909’s substrate temperature control. It requires only substituting microwave energy as the energy source for producing the overheated steam already required by US’909. A known technique used to achieve a predictable result.
Applicant does not provide citation in either US’909 or US’606 establishing that microwave-generated steam is incompatible with US’909’s process, that microwave heating produces vapor of a different chemistry or thermodynamic character than conventionally heated steam, or that the temperature differential of US’909 cannot be maintained when microwave heating is used. the bare assertion that microwave heating would “eliminate the thermal and chemical environment” of US’909 is therefore not supported in either US’909 or US’606 and amounts to attorneys’ speculation, arguments presented by applicant cannot take the place of factually supported objective evidence, see MPEP 2145.
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 ERIN FLANAGAN BERGNER whose telephone number is (571)270-1133. The examiner can normally be reached M-F 8:00-5:00.
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/ERIN F BERGNER/ Primary Examiner, Art Unit 1713
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