DETAILED ACTION
Claims 6, 9-10 and 13 are pending before the Office for review.
In the response filed December 10, 2025:
Claim 6 was amended.
Claim 12 was canceled.
No new matter is present.
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 text of those sections of Title 35, U.S. Code not included in this action can be found in a prior Office action.
Claims 6 and 13 are rejected under 35 U.S.C. 103 as being unpatentable over SHEN et al (U.S. Patent Application Publication 2017/0103901).
With regards to claims 6 and 13, Shen discloses a plasma processing method of subjecting a substrate to deep etching by executing alternately and repeatedly an etching process of etching the substrate by using plasma and a protective film deposition process of depositing a protective film in a recess formed through the etching process by using plasma (Paragraphs [0024]-[0025], [0122]-[0125], [0138], [0147]), wherein in the protective film deposition process, a plasma processing gas being a mixed gas of C4F8 (Paragraph [0146]) and 2,3.3,3-tetrafluoropropene (Paragraphs [0125]-[0126]).
Shen does not explicitly disclose a flow rate ratio of 2,3.3,3- tetrafluoropropene in the mixed gas being 20% or more and 50% or less is used as gas supplied for generating plasma, and a protective film deposition step time which is a time required for one protective film deposition process is set to the shortest time without causing a side wall rupture.
However Shen discloses wherein the etching fluids and hydrogen polymer deposition fluids are introduced into the plasma chamber; wherein the flow rate ranges from approximately 0.1 sccm to approximately 1 slm; wherein the flow rate will vary from tool to tool wherein they are introduced separately into the chamber or a continuous flow of the hydrogen containing polymer deposition; wherein the flow rate of the etching fluid, fluid the hydrogen containing polymer deposition and inert gas may be adjusted to increase or decrease the number of radical species produced (Paragraphs [0139], [0144]). Shen in addition discloses wherein the hydrogen containing polymer fluid permit the etch rate to become more consistent notwithstanding the size of the aperture, the disclosed process may permit deep aperture silicon etching without the use of a stop layer (Paragraph [0135]) Generally, differences in concentration or temperature will not support the patentability of subject matter encompassed by the prior art unless there is evidence indicating such concentration or temperature is critical. "[W]here the general conditions of a claim are disclosed in the prior art, it is not inventive to discover the optimum or workable ranges by routine experimentation." In re Aller, 220 F.2d 454, 456, 105 USPQ 233, 235 (CCPA 1955) MPEP 2144.05(II)(A) Therefore it would have been prima facie obvious to one of ordinary skill in the art prior to the effective filing date of the invention to optimize the flow rate ratio of 2,3.3,3- tetrafluoropropene in the mixed gas to amounts including 20% or more and 50% or less as claimed in order to adjust the concentration of radical species produced to permit deep aperture silicon etching without the use of a stop layer (Paragraphs [0135], [0139], [0144]) as taught by the modified teachings of Shen.
Shen further discloses wherein the polymer deposition is flowed to form the polymer deposition layer wherein the formation of layer is formed to prevent any notching at the interface of the stop layer and Si layer (Paragraphs [0135]) wherein the introduction time of the deposition fluid is shorter than the interaction time of the etching fluid (Paragraph [0136]) wherein the polymer deposition is introduce for a duration such as 2 seconds and formation of a polymer deposition capable of forming polymers in deep etch apertures and easier to remove during the etching process (Paragraphs [0150]-0151]). Generally, differences in concentration or temperature will not support the patentability of subject matter encompassed by the prior art unless there is evidence indicating such concentration or temperature is critical. "[W]here the general conditions of a claim are disclosed in the prior art, it is not inventive to discover the optimum or workable ranges by routine experimentation." In re Aller, 220 F.2d 454, 456, 105 USPQ 233, 235 (CCPA 1955) MPEP 2144.05(II)(A) Therefore it would have been prima facie obvious to one of ordinary skill in the art prior to the effective filing date of the invention to optimize the protective film deposition step time to amounts including the shorts time without causing a side wall rupture because the reference of Shen teaches that such deposition times are enough to prevent any notching (Paragraph [0153]) and forming the polymer deep in the apertures while being easily removed (Paragraphs [0150]-[0151], MPEP 2144.05(II)(A)).
It would have been prima facie obvious to one of ordinary skill in the art prior to the effective filing date of the invention to modify the method of Shen to include the flow rate ratio of 2,3.3,3- tetrafluoropropene in the mixed gas and protective film deposition step time as rendered obvious by Shen because the reference of Shen teaches that wherein the hydrogen containing polymer fluid permit the etch rate to become more consistent notwithstanding the size of the aperture, the disclosed process may permit deep aperture silicon etching without the use of a stop layer (Paragraph [0135]) and one of ordinary skill in the art prior to the effective filing date of the invention would have had a reasonable expectation of predictably achieving the desired deposition and etching using the flow rate ratio and protective film deposition step time as rendered obvious by Shen. MPEP 2143D
Claims 9 and 10 are rejected under 35 U.S.C. 103 as being unpatentable over SHEN et al (U.S. Patent Application Publication 2017/0103901), as applied to claims 6, 13 above, and in further view of INOUE et al (U.S. Patent Application Publication 2013/0001197).
With regards to claims 9 and 10, the modified teachings of Shen renders obvious wherein the etching process and the protective film deposition process, the plasma is generated in a chamber (Paragraph [0143]).
The modified teachings of Shen are silent as to after the deep etching the substrate is completed, a cleaning process step of subjecting the chamber to a cleaning process is executed and wherein in the cleaning process step, the cleaning process is executed in the chamber by turning gas containing O2 into plasma and emission intensity of CO in the chamber is measured, and when a point at which an absolute value of a rate of change of the emission intensity of CO reaches 1 % or less is defined as an end point X, and when an elapsed time from start of execution of the cleaning process step to the end point X is defined as TO, a cleaning time T in the cleaning process step is determined by the following formula (1) T=1.5T0...(1).
Inoue discloses performing plasma processing process on a substrate wherein the plasma process comprises using a depositional gas and subsequent to processing the substrate; with either a substrate or no substrate in the chamber performing a cleaning process in the chamber wherein the plasma cleaning removes film deposited on the inner wall of the processing chamber; wherein an O2 gas is used in the plasma cleaning (Paragraphs [[0004], [0020]-[p0021], [0026][0046], [0051]-[0055]) which renders obvious a cleaning process step of subjecting the chamber to a cleaning process is executed and wherein in the cleaning process step, the cleaning process is executed in the chamber by turning gas containing O2 into plasma. Inoue further discloses if the processing time of the plasma cleaning is too short the deposit on the inner wall of the processing chamber cannot be removed and if too long specific parts in the processing chamber are changed in quality; wherein the processing time of the plasma cleaning need to be optimized by monitoring a transition of emission of light at a wavelength of a carbon component using a light emission detection unit during the plasma cleaning; wherein the time period required for the light emission intensity of the a carbon component to become less than 25% of a maximum value of the light emission intensities; a time period is in the range of the calculated time period to 1.5 time thereof is taken as an optimum value of the processing time of the plasma cleaning (Paragraph [0054]-[0055]). On of ordinary skill in the art would understand the cleaned carbon deposit to include CO with a cleaning gas of O2. As such Shen as modified by Inoue renders obvious to after the deep etching the substrate is completed, a cleaning process step of subjecting the chamber to a cleaning process is executed and wherein in the cleaning process step, the cleaning process is executed in the chamber by turning gas containing O2 into plasma and emission intensity of CO in the chamber is measured, and when a point at which an absolute value of a rate of change of the emission intensity of CO reaches 1 % or less is defined as an end point X, and when an elapsed time from start of execution of the cleaning process step to the end point X is defined as TO, a cleaning time T in the cleaning process step is determined by the following formula (1) T=1.5T0...(1).
It would have been prima facie obvious to one of ordinary skill in the art prior to the effective filing date of the invention to modify the method of Shen to include cleaning and emission intensity as rendered obvious by Inoue because the reference of Inoue teaches that such plasma cleaning sufficiently removes unwanted deposition without the generating of additional particles which may contaminate the wafer to be processes (Paragraphs [0004], [0054]-[0055]) and one of ordinary skill in the art prior to the effective filing date of the invention would have had a reasonable expectation of predictably achieving the desired substrate processing using the cleaning as rendered obvious by Inoue. MPEP 2143D
Response to Arguments
Applicant's arguments filed December 10, 2025 have been fully considered but they are not persuasive.
Applicant argues on pages 4-10 of Applicant’s response that the cited prior art fails to teach or render obvious the limitations of claim 6.
In particular, Applicant argues that Shen does not teach controlling the protective film deposition step of claim 6 as amended, in connection with sidewall rupture. Applicant argues that while Shen does discuss the time for the depositing step, see paragraph [0160], this discussion of time is merely identifying the time for deposition; it does not lead to the control specified in claim 6, as amended. It is the Applicant’s position that while the specification was conducted under specific etching step time and specific protective film disposition step time, the use of these conditions does not taint the objective evidence of unobviousness associated with the comparative testing.
Applicant further argues that the flow rate ratio of the mixed gas results in a combination of improvements not suggested by the prior art. It Applicant’s position that there is a showing commensurate in scope with the range of a flow rate ratio being 20 or more and 50% or less based on the trend demonstrated by Applicant’s claimed invention. It is the Examiner’s Any further assertion that claim 6 is obvious in this regard would be the impermissible use of hindsight and such a rejection could not be sustained on appeal. This is found unpersuasive.
It is the Examiner’s position that the cited prior art renders obvious Applicant’s claimed invention including “a plasma processing gas being a mixed gas of C4F8 and 2,3,3,3-tetrafluoropropene and having a flow rate ratio of 2,3,3,3- tetrafluoropropene in the mixed gas being 20% or more and 50% or less is used as gas supplied for generating plasma, and a protective film deposition step time which is a time required for one protective film deposition process is set to the shortest time without causing a side wall rupture.”
It is the Examiner’s position that Shen discloses wherein the polymer deposition is flowed to form the polymer deposition layer wherein the formation of layer is formed to prevent any notching at the interface of the stop layer and Si layer (Paragraphs [0135]) wherein the introduction time of the deposition fluid is shorter than the interaction time of the etching fluid (Paragraph [0136]) wherein the polymer deposition is introduce for a duration such as 2 seconds and formation of a polymer deposition capable of forming polymers in deep etch apertures and easier to remove during the etching process (Paragraphs [0150]-0151]). The Examiner has interpreted the disclosure of Shen’s “notches” as rendering obvious Applicant’s “side wall ruptures.’ As such Shen’s disclosure of forming the polymer deposition layer to an extent to prevent any notching (Paragraph [0135]) wherein the depositing and etching are done for a duration of time to etch the desired aspect ratio while preventing the notching and removing the polymer deposition layer when necessary (Paragraphs [0135]-[0137], [0150]-[0152]) renders obvious Applicant’s claimed limitation.
With regards to Applicant flow rat ratio, the Examiner maintains that Applicant’s showing of unexpected result is not commensurate in scope with the claim. Whether the unexpected results are the result of unexpectedly improved results or a property not taught by the prior art, the "objective evidence of nonobviousness must be commensurate in scope with the claims which the evidence is offered to support." In other words, the showing of unexpected results must be reviewed to see if the results occur over the entire claimed range. In re Clemens, 622 F.2d 1029, 1036, 206 USPQ 289, 296 (CCPA 1980) MPEP 716.02(d) It is the Examiner’s position that Applicant’s specification does not show the criticality of the currently claimed range with regards to Applicant’s processing conditions. To establish unexpected results over a claimed range, applicants should compare a sufficient number of tests both inside and outside the claimed range to show the criticality of the claimed range. In re Hill, 284 F.2d 955, 128 USPQ 197 (CCPA 1960) MPEP 716.02(d)(II) Applicant has not demonstrated a sufficient number of test outside the claimed range to show the criticality of the range.
Applicant’s specification indicates that when the deposition of the protective film is too long the thickness of the protective film deposited on the bottom of the trench is increased and not sufficiently removes… when it is too short the result is sidewall rupture (Applicant’s Published Specification Paragraph [0072]). Shen discloses that the hydrogen containing polymer is deposited to prevent any notching at the interface of the stop layer and Si layer (Paragraph [0135]) for a duration such as 2 seconds as a polymer formation step (Paragraph [0150]), wherein the deposited polymer is easier to remove (Paragraphs [0150]-[0151]). In response to applicant's argument that the examiner's conclusion of obviousness is based upon improper hindsight reasoning, it must be recognized that any judgment on obviousness is in a sense necessarily a reconstruction based upon hindsight reasoning. But so long as it takes into account only knowledge which was within the level of ordinary skill at the time the claimed invention was made, and does not include knowledge gleaned only from the applicant's disclosure, such a reconstruction is proper. See In re McLaughlin, 443 F.2d 1392, 170 USPQ 209 (CCPA 1971). Therefore it is the Examiner’s position that one of ordinary skill would like to optimize the processing conditions of Shen in light of Shen’s teaching. As such Applicant’s arguments are found unpersuasive. As to the remaining dependent claims they remain rejected as no separate arguments have been provided.
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.
Any inquiry concerning this communication or earlier communications from the examiner should be directed to STEPHANIE P. DUCLAIR whose telephone number is (571)270-5502. The examiner can normally be reached 9-6:30 M-F.
Examiner interviews are available via telephone, in-person, and video conferencing using a USPTO supplied web-based collaboration tool. To schedule an interview, applicant is encouraged to use the USPTO Automated Interview Request (AIR) at http://www.uspto.gov/interviewpractice.
If attempts to reach the examiner by telephone are unsuccessful, the examiner’s supervisor, Joshua Allen can be reached at 571-270-3176. The fax phone number for the organization where this application or proceeding is assigned is 571-273-8300.
Information regarding the status of published or unpublished applications may be obtained from Patent Center. Unpublished application information in Patent Center is available to registered users. To file and manage patent submissions in Patent Center, visit: https://patentcenter.uspto.gov. Visit https://www.uspto.gov/patents/apply/patent-center for more information about Patent Center and https://www.uspto.gov/patents/docx for information about filing in DOCX format. For additional questions, contact the Electronic Business Center (EBC) at 866-217-9197 (toll-free). If you would like assistance from a USPTO Customer Service Representative, call 800-786-9199 (IN USA OR CANADA) or 571-272-1000.
/STEPHANIE P DUCLAIR/Primary Examiner, Art Unit 1713