DETAILED ACTION
This Office action responds to Applicant’s invention filed on 09/17/2024.
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 . In the event the determination of the status of the application as subject to AIA 35 is incorrect, any correction of the statutory basis (i.e., changing from AIA to pre-AIA ) for a 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.
Amendment Status
The present Office action is made with all previously suggested amendments being fully considered. Accordingly, pending in this Office action are claims 11-20.
Information Disclosure Statement (IDS)
Acknowledgement is made of Applicant’s Information Disclosure Statement (IDS) form PTO-1449. The IDS has been considered.
Drawings Objection
The drawings are objected to as failing to comply with 37 CFR 1.84(p)(4) because:
The indicated elements in the downward drawing (annotated fig. 3 from the instant application) are not designated.
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No new matter should be entered.
Corrected drawing sheets in compliance with 37 CFR 1.121(d) are required in reply to the Office action to avoid abandonment of the application. Any amended replacement drawing sheet should include all of the figures appearing on the immediate prior version of the sheet, even if only one figure is being amended. Each drawing sheet submitted after the filing date of an application must be labeled in the top margin as either “Replacement Sheet” or “New Sheet” pursuant to 37 CFR 1.121(d). If the changes are not accepted by the examiner, the applicant will be notified and informed of any required corrective action in the next Office action. The objection to the drawings will not be held in abeyance.
Specification Objection
The specification has been checked to the extend necessary to determine the presence of possible minor errors. However, the Applicant’s cooperation is requested in correcting any errors of which Applicant may become aware in the specification.
The specification does not contain the indications for the elements which are not designated in the annotated fig. 3 of the instant application.
Claim Rejections - 35 USC § 112
The following is a quotation of 35 U.S.C. 112(b):
(b) CONCLUSION. —The specification shall conclude with one or more claims particularly pointing out and distinctly claiming the subject matter which the inventor or a joint inventor regards as the invention.
Claims 11 and 18 are rejected under 35 U.S.C. 112(b) as being indefinite.
Claims 11 and 18 is indefinite for failing to particularly point out and distinctly claim the subject matter which the inventor or a joint regard as the invention.
Claims 11 and 18 recite the limitation "… applying a mask layer to the top side, the first side surface, the second side surface, the first trench bottom surface; and the second trench bottom surface; …”. The claim should be instead defined such as "… applying a mask layer to the top side, the first side surface, the second side surface, the first trench bottom surface, and the second trench bottom surface; …” (a comma after “and the second trench bottom surface”).
Claims 18 recites the limitation "… creation of a structured mask by removing the mask layer in certain regions of the mask layer”. The claim should be instead defined such as “… creation of a structured mask by removing the mask layer in certain regions of the mask layer”.
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.
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.
Claims 11, 13-15, and 18-20 are rejected under 35 U.S.C. 103 as obvious over Sung (US 2020/0135573) in view of Seok (US 2024/0120417) in further view of Ando (US 2017/0005090).
Regarding claim 11, Sung shows (see, e.g., Sung: figs. 1A-1D, and fig. 1A annotated) most aspects of the instant invention including a method for producing a power semiconductor component 200 (see, e.g., Sung: fig. 2, and par. [0007]) having a plurality of fins, the method comprising the following steps:
Creating a plurality of mesas 106 starting from a front side of a semiconductor substrate 102 into a drift layer of the semiconductor substrate 102 by etching (see, e.g., Sung: par. [0007])
wherein:
Each mesa 106 includes a top side that corresponds to a region of the front side of the semiconductor substrate102
Each mesa 1-6 is arranged between a first trench and a second trench
The first trench includes a first trench bottom surface and the second trench comprises a second trench bottom surface
Each mesa 106 includes a first side surface and a second side surface
The first side surface corresponds to a first trench side surface of the first trench and the second side surface corresponds to a second trench side surface of the second trench
Applying a mask layer 108/110 to the top side, the first side surface, the second side surface, the first trench bottom surface, and the second trench bottom surface
Creating a structured mask 110 by removing the mask layer 110 in certain regions of the mask layer 110, so that an exposed surface is created
The exposed surface includes the first side surface, the top side in certain regions and the first trench bottom surface
Creating fins by machining the exposed surface
Completing the power semiconductor component 200
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However, Sung fails (see, e.g., Sung: figs. 1A-1D) to show that each mesa 106 has a width greater than 500 nm. Sung also shows that the mesa has a width between 8 nm to 15 nm (see, e.g., Sung: par. [0021]). Seok, in a similar method to Sung, shows (see, e.g., Seok: figs. 6-7) that the mesa width is greater than 500nm (see, e.g., Seok: par. [0063]). Seok also shows that the mesa width is greater than 500nm in order to form fins for a vertical FinFET power transistor with high breakdown voltages while offering significant reductions in the specific on-resistance (see, e.g., Seok: par. [0002]).
It would have been obvious at the time of filing the invention to one of ordinary skill in the art to include the mesa width greater of 500 nm of Seok in the method of Sung, in order to form fins for a vertical FinFET power transistor with high breakdown voltages while offering significant reductions in the specific on-resistance.
Furthermore, it is noted that the specification fails to provide teachings about the criticality of having different mesa width, and differences in widths will not support the patentability of subject matter encompassed by the prior art unless there is evidence indicating such differences are critical. “Where the general conditions of a claim are disclosed in the prior art, it is not inventive to discover the workable ranges by routine experimentation”. In re Aller, 220 F.2d 454,456,105 USPQ 233, 235 (CCPA 1955).
Accordingly, since the applicant has not established the criticality (see next paragraph below) of the mesa width, and Sung and Seok have identified such mesa widths as result-effective variables subject to optimization, it would have been obvious to one of ordinary skill in the art to have these widths to be different in the method of Sung in view of Seok.
CRITICALITY
The specification contains no disclosure of either the critical nature of the claimed width differences or any unexpected results arising therefrom. Where patentability is said to be based upon particular chosen dimensions or upon another variable recited in a claim, the applicant must show that the chosen dimensions are critical. In re Woodruff, 919 F.2d 1575, 1578, 16 USPQ2d 1934, 1936 (Fed. Cir. 1990).
Sung in view of Seok fails (see, e.g., Sung: figs. 1A-1D, and see, e.g., Seok: figs. 6-7) to show the method step of removing the structured mask 110. Ando, in a similar method to Sung in view of Seok, shows (see, e.g., Ando: figs. 21-24) the method step of removing the structured mask (see, e.g., Ando: trimmed fin hard mask, and element 2002). Ando also shows (see, e.g., Ando: figs. 21-24) that by using the method step of removing the structured mask, the fins are prepared for further use in the method of forming complete FinFET devices (see, e.g., Ando: par. [0077]).
It would have been obvious at the time of filing the invention to one of ordinary skill in the art to include the method step of removing the structured mask of Ando in the method of Sung in view of Seok, for further use of the fins in the method of forming complete FinFET devices.
Regarding claim 13, Sung in view of Seok in view of Ando shows (see, e.g., Sung: figs. 1A-1D) that the mask layer 108/110 includes SiN (see, e.g., Sung: par. [0016]) and [0017]).
Regarding claim 14, Sung in view of Seok in view of Ando shows (see, e.g., Ando: figs. 21-24) that the fins are created using thermal oxidation (see, e.g., Ando: par. [0055]).
Regarding claim 15, Sung in view of Seok in view of Ando shows (see, e.g., Seok: figs. 6-7) that the semiconductor substrate includes GaN (see, e.g., Seok: claim 1, and par. [0058]).
Regarding claim 18, Sung shows (see, e.g., Sung: figs. 1A-1D, and fig. 1A annotated) most aspects of the instant invention including a power semiconductor component 200 (see, e.g., Sung: fig. 2, and par. [0007]) having a plurality of fins produced by:
Creation a plurality of mesas 106 starting from a front side of a semiconductor substrate 102 into a drift layer of the semiconductor substrate 102 by etching (see, e.g., Sung: par. [0007])
wherein:
Each mesa 106 includes a top side that corresponds to a region of the front side of the semiconductor substrate102
Each mesa 1-6 is arranged between a first trench and a second trench
The first trench includes a first trench bottom surface and the second trench comprises a second trench bottom surface
Each mesa 106 includes a first side surface and a second side surface
The first side surface corresponds to a first trench side surface of the first trench and the second side surface corresponds to a second trench side surface of the second trench
Application of a mask layer 108/110 to the top side, the first side surface, the second side surface, the first trench bottom surface, and the second trench bottom surface
Creation of a structured mask 110 by removing the mask layer 110 in certain regions of the mask layer 110, so that an exposed surface is created
The exposed surface includes the first side surface, the top side in certain regions and the first trench bottom surface
Creation of fins by machining the exposed surface
Completion of the power semiconductor component 200
However, Sung fails (see, e.g., Sung: figs. 1A-1D) to show that each mesa 106 has a width greater than 500 nm. Sung also shows that the mesa has a width between 8 nm to 15 nm (see, e.g., Sung: par. [0021]). Seok, in a similar method to Sung, shows (see, e.g., Seok: figs. 6-7) that the mesa width is greater than 500nm (see, e.g., Seok: par. [0063]). Seok also shows that the mesa width is greater than 500nm in order to form fins for a vertical FinFET power transistor with high breakdown voltages while offering significant reductions in the specific on-resistance (see, e.g., Seok: par. [0002]).
It would have been obvious at the time of filing the invention to one of ordinary skill in the art to include the mesa width greater of 500 nm of Seok in the method of Sung, in order to form fins for a vertical FinFET power transistor with high breakdown voltages while offering significant reductions in the specific on-resistance.
Furthermore, it is noted that the specification fails to provide teachings about the criticality of having different mesa width, and differences in widths will not support the patentability of subject matter encompassed by the prior art unless there is evidence indicating such differences are critical. “Where the general conditions of a claim are disclosed in the prior art, it is not inventive to discover the workable ranges by routine experimentation”. In re Aller, 220 F.2d 454,456,105 USPQ 233, 235 (CCPA 1955).
Accordingly, since the applicant has not established the criticality (see paragraph 13) of the mesa width, and Sung and Seok have identified such mesa widths as result-effective variables subject to optimization, it would have been obvious to one of ordinary skill in the art to have these widths to be different in the method of Sung in view of Seok.
Sung in view of Seok fails (see, e.g., Sung: figs. 1A-1D, and see, e.g., Seok: figs. 6-7) to show the method step of removing the structured mask 110. Ando, in a similar method to Sung in view of Seok, shows (see, e.g., Ando: figs. 21-24) the method step of removing the structured mask (see, e.g., Ando: trimmed fin hard mask, and element 2002). Ando also shows (see, e.g., Ando: figs. 21-24) that by using the method step of removing the structured mask, the fins are prepared for further use in the method of forming complete FinFET devices (see, e.g., Ando: par. [0077]).
It would have been obvious at the time of filing the invention to one of ordinary skill in the art to include the method step of removing the structured mask of Ando in the method of Sung in view of Seok, for further use of the fins in the method of forming complete FinFET devices.
Regarding claim 19, Sung in view of Seok in view of Ando shows (see, e.g., Seok: figs. 6-7) that the power semiconductor component is a FinFet (see, e.g., Seok: claim 1).
Regarding claim 20, Sung in view of Seok in view of Ando shows (see, e.g., Seok: figs. 6-7) that the power semiconductor component is a FinFet (see, e.g., Seok: claim 1)
(e.g., because a FinFET (Fin Field-Effect Transistor) is a multi-gate MOSFET in which the gate surrounds the channel on multiple sides — typically two, three, or four — forming a 3D fin-shaped structure).
Claim 12 is rejected under 35 U.S.C. 103 as obvious over Sung in view of Seok in view of Ando in further view of Huang (US 2023/0230876).
Regarding claim 12, Sung in view of Seok in view of Ando shows (see, e.g., Sung: figs. 1A-1D, see, e.g., Seok: figs. 6-7, and see, e.g., Ando: figs. 21-24) most aspects of the instant invention including a semiconductor substrate 102.
However, Sung in view of Seok in view of Ando fails (see, e.g., Sung: figs. 1A-1D, see, e.g., Seok: figs. 6-7, and see, e.g., Ando: figs. 21-24) to show that the semiconductor substrate includes SiC. Sung in view of Seok in view of Ando also shows (see, e.g., Sung: figs. 1A-1D) that the semiconductor substrate is from silicon (see, e.g., Sung: par. [0016]).
Huang, in a similar method to Sung in view of Seok in view of Ando, also teaches (see, e.g., Huang: fig. 2) that the semiconductor substrate 20 includes SiC (see, e.g., Huang: par. [0010]).
Therefore, it would have been obvious at the time of the invention to one of ordinary skill in the art to use either the SiC semiconductor substrate of Huang or the silicon semiconductor substrate of Sung in view of Seok in view of Ando because these were recognized in the semiconductor art for their use as semiconductor substrates in methods of manufacturing semiconductor devices, as taught by Huang and by Sung in view of Seok in view of Ando, and selecting between known equivalents would be within the level of ordinary skill in the art. KSR International Co. v. Teleflex Inc., 550 U.S.--,82 USPQ2d 1385 (2007).
Claim 16 is rejected under 35 U.S.C. 103 as obvious over Sung in view of Seok in view of Ando in further view of Pena (US 9799534).
Regarding claim 16, Sung in view of Seok in view of Ando shows (see, e.g., Sung: figs. 1A-1D, see, e.g., Seok: figs. 6-7, and see, e.g., Ando: figs. 21-24) most aspects of the instant invention including a mask layer 108/110.
However, Sung in view of Seok in view of Ando fails (see, e.g., Sung: figs. 1A-1D, see, e.g., Seok: figs. 6-7, and see, e.g., Ando: figs. 21-24) to show that the mask layer includes Ti or TiO2. Sung in view of Seok in view of Ando also shows (see, e.g., Sung: figs. 1A-1D) that the mask layer is from silicon nitride (see, e.g., Sung: par. [0016]).
Pena, in a similar method to Sung in view of Seok in view of Ando, also teaches (see, e.g., Pena: figs. 1C-1D) that the mask layer 130 includes Ti or TiO2 (see, e.g., Pena: col.3/II.52-67 - col.4/II.1-4).
Therefore, it would have been obvious at the time of the invention to one of ordinary skill in the art to use either the TiO2 mask layer of Pena or the silicon nitride mask layer of Sung in view of Seok in view of Ando because these were recognized in the semiconductor art for their use as mask layers in methods of manufacturing semiconductor devices, as taught by Pena and by Sung in view of Seok in view of Ando, and selecting between known equivalents would be within the level of ordinary skill in the art. KSR International Co. v. Teleflex Inc., 550 U.S.--,82 USPQ2d 1385 (2007).
Claim 17 is rejected under 35 U.S.C. 103 as obvious over Sung in view of Seok in view of Ando in further view of Lo (US 2024/0337947).
Regarding claim 17, Sung in view of Seok in view of Ando shows (see, e.g., Sung: figs. 1A-1D, see, e.g., Seok: figs. 6-7, and see, e.g., Ando: figs. 21-24) most aspects of the instant invention including a method step of etching the fins 106.
However, Sung in view of Seok in view of Ando fails (see, e.g., Sung: figs. 1A-1D, see, e.g., Seok: figs. 6-7, and see, e.g., Ando: figs. 21-24) to show that the method of etching the fin 106 uses TMAH. Sung in view of Seok in view of Ando is silent (see, e.g., Sung: figs. 1A-1D) about the etchant.
Lo, in a similar method to Sung in view of Seok in view of Ando, also teaches (see, e.g., Lo: figs. 11-12) that the fins 104 are created using TMAH (see, e.g., Lo: par. [0072]).
Therefore, it would have been obvious at the time of the invention to one of ordinary skill in the art to use either the TMAH etchant to make the fins of Lo or the etchant of Sung in view of Seok in view of Ando because these were recognized in the semiconductor art for their use as etchants for making fins in methods of manufacturing semiconductor devices, as taught by Lo and by Sung in view of Seok in view of Ando, and selecting between known equivalents would be within the level of ordinary skill in the art. KSR International Co. v. Teleflex Inc., 550 U.S.--,82 USPQ2d 1385 (2007).
Conclusion
Any inquiry concerning this communication or earlier communications from the examiner should be directed to TIBERIU DAN ONUTA whose telephone number is (571) 270-0074 and between the hours of 9:00 AM to 5:00 PM (Eastern Standard Time) Monday through Friday or by e-mail via Tiberiu.Onuta@uspto.gov. If attempts to reach the examiner by telephone or email are unsuccessful, the examiner's supervisor, Wael Fahmy, can be reached on (571) 272-1705.
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/TIBERIU DAN ONUTA/Examiner, Art Unit 2814
/WAEL M FAHMY/Supervisory Patent Examiner, Art Unit 2814
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