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 .
Priority
Acknowledgment is made of applicant's claim for foreign priority based on an application filed in China on 07/19/2023. It is noted, however, that applicant has not filed a certified copy of the CN202310890183.8 application as required by 37 CFR 1.55.
Specification
Applicant is reminded of the proper language and format for an abstract of the disclosure.
The abstract should be in narrative form and generally limited to a single paragraph on a separate sheet within the range of 50 to 150 words in length. The abstract should describe the disclosure sufficiently to assist readers in deciding whether there is a need for consulting the full patent text for details.
The language should be clear and concise and should not repeat information given in the title. It should avoid using phrases which can be implied, such as, “The disclosure concerns,” “The disclosure defined by this invention,” “The disclosure describes,” etc. In addition, the form and legal phraseology often used in patent claims, such as “means” and “said,” should be avoided.
The abstract of the disclosure is objected to because the abstract has implied language shown as underlined below.
For example, the abstract cites “The present disclosure provides a surface modification method for reducing…” and “…In a wafer thinning process applied in the present disclosure, the oxidation treatment for the silicon…” It is suggested to change the abstract to “A surface modification method for reducing…” and “…In a wafer thinning process, the oxidation treatment for the silicon…”
A corrected abstract of the disclosure is required and must be presented on a separate sheet, apart from any other text. See MPEP § 608.01(b).
The disclosure is objected to because of the following informalities: Paragraph 0026 reads: "the silicon surface of the wafer to be . Appropriate correction is required.
Claim Objections
Claim 5 objected to because of the following informalities: Claim 5 recites the limitation "...and a duration of the Appropriate correction is required.
Claim 6 is objected to because of the following informalities: Claim 6 recites the limitation "…wherein the cleaning solution in step II is SC1". Based on para. [0014] of the Brief Summary, it should read "…wherein the cleaning solution in step II is an ammonia hydroxide-hydrogen peroxide water mixture (SC1)". If an acronym is used, it must be clearly defined the first time it appears, preferably in its fully expanded form, and it must have clear antecedent basis in the specification. Appropriate correction is required.
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.
The following is a quotation of 35 U.S.C. 112 (pre-AIA ), second paragraph:
The specification shall conclude with one or more claims particularly pointing out and distinctly claiming the subject matter which the applicant regards as his invention.
Claim 5 is rejected under 35 U.S.C. 112(b) or 35 U.S.C. 112 (pre-AIA ), second paragraph, as being indefinite for failing to particularly point out and distinctly claim the subject matter which the inventor or a joint inventor (or for applications subject to pre-AIA 35 U.S.C. 112, the applicant), regards as the invention.
The term “at a ppm level” in claim 5 is a relative term which renders the claim indefinite. The term “at a ppm level” is not defined by the claim, the specification does not provide a standard for ascertaining the requisite degree, and one of ordinary skill in the art would not be reasonably apprised of the scope of the invention. The term "at a ppm level" renders the concentration of ozone used in the oxidization treatment indefinite because it lacks boundaries.
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.
Claim(s) 1-2, 4-8 are rejected under 35 U.S.C. 103 as being unpatentable over Wu et al. (US 10151048 B1; hereinafter “Wu”) in view of Wu et al. (CN 103426744 A; hereinafter “Wu ‘744”) (All the paragraphs cited here regarding Wu’744 refer to the attached English translation of CN 103426744 A).
Regarding claim 1, Wu teaches in figs. 1-4, a surface modification method for reducing wafer defects, at least comprising:
step I (e.g., S11 in fig. 1), providing a wafer (10), and performing a first time wet etching (91) on a silicon surface of the wafer (RS) (fig. 2; Col. 2, Lines 49-56, etching process 91 may include a wet etching process);
step II (e.g., S12 in fig. 1), performing an oxidization treatment (92) on the silicon surface of the wafer (RS) to reduce surface roughness (fig. 3; Col. 2, Lines 65-67);
step III (e.g., S13 in fig. 1), performing a second time wet etching (93) on the silicon surface of the wafer (RS) (fig. 4; Col. 3, Lines 25-29, since the cleaning step removes the oxide layer, it is being considered equivalent to a wet etching step that removes the oxide layer).
Wu does not expressly disclose cleaning the silicon surface with a cleaning solution which removes contamination from the oxidization treatment after the oxidization treatment.
In the same field of endeavor, Wu ‘744 teaches a cleaning process with a cleaning solution used to remove surface particles from the substrate, such as native oxides or other contaminants (para. 0057). 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 described in Wu such that a cleaning process with a cleaning solution is performed on the silicon surface after the oxidization treatment with a reasonable expectation of success. One would have been motivated to add the cleaning process with the cleaning solution as Wu ‘744 teaches to remove contamination, such as native oxides, from the silicon surface after the oxidization treatment (para. 0057).
Regarding claim 2, Wu, as modified by Wu ‘744, discloses the method of claim 1.
Wu does not expressly disclose wherein an etchant for the first time wet etching in step I is tetramethylammonium hydroxide.
In the same field of endeavor, Wu ‘744 teaches tetramethylammonium hydroxide (TMAH) as an alkali solution for silicon substrate texturing (etching) (para. 0060).
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 described in Wu such that tetramethylammonium hydroxide (TMAH) is used as an etchant for the first time wet etching in step I with a reasonable expectation of success. One would have been motivated to use tetramethylammonium hydroxide (TMAH), as Wu ‘744 teaches, as it is an aqueous composition effective for texturing (etching) of the substrate (silicon) surface (para. 0060).
Regarding claim 4, Wu, as modified by Wu ‘744, discloses the method of claim 1.
Wu further discloses wherein the oxidization (92) on the silicon surface of the wafer (RS) to reduce the surface roughness is performed with ozone (O3) in step II (fig. 3; Col. 3, Lines 2-7).
Regarding claim 5, Wu, as modified by Wu ‘744, discloses the method of claim 1.
Wu does not expressly disclose wherein a concentration of O3 in step II is 1ppm-100ppm (as best understood); and a duration of the oxidation treatment is no more than 1 minute.
In the same field of endeavor, Wu ‘744 teaches a concentration of ozone (O3) of about 1ppm – 30ppm for the pre-cleaning oxidation process (para. 0057) and a duration for about 5 seconds to about 600 seconds (para. 0057). Note, Wu ‘744 discloses an ozone (O3) concentration in ppm (para. 57), as required by the claim; and a duration for between 5 and 600 seconds, which overlaps a narrower claimed range of less than 1 minute.
MPEP ¶2145.05-I states:
"[A] prior art reference that discloses a range encompassing a somewhat narrower claimed
range is sufficient to establish a prima facie case of obviousness." In re Peterson, 315 F.3d
1325, 1330, 65 USPQ2d 1379, 1382-83 (Fed. Cir. 2003). See also In re Harris, 409 F.3d 1339,
74 USPQ2d 1951 (Fed. Cir. 2005) (claimed alloy held obvious over prior art alloy that taught
ranges of weight percentages overlapping, and in most instances completely encompassing,
claimed ranges; furthermore, narrower ranges taught by reference overlapped all but one range
in claimed invention).
In the case where the claimed ranges "overlap or lie inside ranges disclosed by the prior art" a
prima facie case of obviousness exists. In re Wertheim, 541 F.2d 257, 191 USPQ 90 (CCPA
1976); In re Woodruff, 919 F.2d 1575, 16 USPQ2d 1934 (Fed. Cir. 1990) (The prior art taught carbon monoxide concentrations of "about 1-5%" while the claim was limited to "more than 5%."
The court held that "about 1-5%" allowed for concentrations slightly above 5% thus the ranges
overlapped.); In re Geisler, 116 F.3d 1465, 1469-71, 43 USPQ2d 1362, 1365-66 (Fed. Cir.
1997) (Claim reciting thickness of a protective layer as falling within a range of "50 to 100
Angstroms" considered prima facie obvious in view of prior art reference teaching that "for
suitable protection, the thickness of the protective layer should be not less than about 10 nm
[i.e., 100 Angstroms]." The court stated that "by stating that ‘suitable protection’ is provided if the
protective layer is ‘about’ 100 Angstroms thick, [the prior art reference] directly teaches the use of a thickness within [applicant’s] claimed range.").
Therefore, it 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 to employ the teachings of Wu ‘744 into the surface modification method of Wu to control the degree at which the wafer is exposed to ozone (O3) during the oxidation process and to effectively remove all etching defects generated by the initial recess formation etching process.
Regarding claim 6, Wu, as modified by Wu ‘744, discloses the method of claim 1.
Wu ‘744 further discloses wherein the cleaning solution in step II is SC1 (para. 0057).
Regarding claim 7, Wu, as modified by Wu ‘744, discloses the method of claim 6.
Wu does not expressly disclose wherein a duration for the cleaning the silicon surface in step II is no more than 1 minute.
In the same field of endeavor, Wu ‘744 teaches cleaning solution can be on the substrate for about 5 seconds to about 600 seconds, which encompasses a narrower claimed range of less than 1 minute.
MPEP ¶2145.05-I states:
"[A] prior art reference that discloses a range encompassing a somewhat narrower claimed
range is sufficient to establish a prima facie case of obviousness." In re Peterson, 315 F.3d 1325, 1330, 65 USPQ2d 1379, 1382-83 (Fed. Cir. 2003). See also In re Harris, 409 F.3d 1339,
74 USPQ2d 1951 (Fed. Cir. 2005) (claimed alloy held obvious over prior art alloy that taught
ranges of weight percentages overlapping, and in most instances completely encompassing,
claimed ranges; furthermore, narrower ranges taught by reference overlapped all but one range
in claimed invention).
In the case where the claimed ranges "overlap or lie inside ranges disclosed by the prior art" a
prima facie case of obviousness exists. In re Wertheim, 541 F.2d 257, 191 USPQ 90 (CCPA
1976); In re Woodruff, 919 F.2d 1575, 16 USPQ2d 1934 (Fed. Cir. 1990) (The prior art taught
carbon monoxide concentrations of "about 1-5%" while the claim was limited to "more than 5%."
The court held that "about 1-5%" allowed for concentrations slightly above 5% thus the ranges
overlapped.); In re Geisler, 116 F.3d 1465, 1469-71, 43 USPQ2d 1362, 1365-66 (Fed. Cir.
1997) (Claim reciting thickness of a protective layer as falling within a range of "50 to 100
Angstroms" considered prima facie obvious in view of prior art reference teaching that "for
suitable protection, the thickness of the protective layer should be not less than about 10 nm
[i.e., 100 Angstroms]." The court stated that "by stating that ‘suitable protection’ is provided if the
protective layer is ‘about’ 100 Angstroms thick, [the prior art reference] directly teaches the use
of a thickness within [applicant’s] claimed range.").
Therefore, it 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 to employ the teachings of Wu ‘744 into the surface modification method of Wu and arrive at the claimed duration for the cleaning the silicon surface to control the degree at which the wafer is exposed to standard clean 1 (SC1) solution during the cleaning process and remove all undesirable contaminants, surface damage and/or multiple step process may affect the subsequent processing steps of other materials (para. 0057 of Wu’744).
Regarding claim 8, Wu, as modified by Wu ‘744, discloses the method of claim 1.
Wu does not expressly disclose wherein an etchant for the second time wet etching in step III is tetramethylammonium hydroxide.
In the same field of endeavor, Wu ‘744 teaches tetramethylammonium hydroxide (TMAH) as an alkali solution for silicon substrate texturing (etching) (para. 0060). 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 described in Wu such that tetramethylammonium hydroxide (TMAH) is used as an etchant for the second time wet etching in step III with a reasonable expectation of success. One would have been motivated to use tetramethylammonium hydroxide (TMAH), as Wu ‘744 teaches, as it is an aqueous composition effective for texturing (etching) of the substrate (silicon) surface (para. 0060).
Claim(s) 3, 9 are rejected under 35 U.S.C. 103 as being unpatentable over Wu, as modified by Wu '744, in view of Lawrence et al. (TW I697593 B; hereinafter "Lawrence"). (All the paragraphs regarding Lawrence cited here refer to the attached English translation of TW I697593 B)
Regarding claim 3, Wu, as modified by Wu ‘744, discloses the method of claim 1.
Wu, as modified by Wu ‘744, does not expressly disclose wherein an auto process control system is applied in step I to monitor a thickness of an epitaxial layer on the wafer before the first time wet etching.
In the same field of endeavor Lawrence teaches a process controller that measures the initial thickness of the wafer and calculates a respective first etching depth of each of the plurality of radial positions (Page 4, para. 3). 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 described in Wu, as modified by Wu ‘744, such that a process controller is applied in step I to monitor the thickness of the epitaxial layer on the wafer before the first time wet etching with a reasonable expectation of success. One would have been motivated to use the process controller so that the wafer can be measured in real time while the wafer is being etched and an etching depth can be effectively controlled (Page 4, para. 3).
Regarding claim 9, Wu, as modified by Wu ‘744, discloses the method of claim 1.
Wu, as modified by Wu ‘744, does not expressly disclose wherein an auto process control system is applied in step III to monitor a thickness of an epitaxial layer on the wafer before the second time wet etching.
In the same field of endeavor Lawrence teaches a process controller that measures the initial thickness of the wafer and calculates a respective first etching depth of each of the plurality of radial positions (Page 4, para. 3). 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 described in Wu, as modified by Wu ‘744, such that a process controller is applied in step III to monitor the thickness of the epitaxial layer on the wafer before the second time wet etching with a reasonable expectation of success. One would have been motivated to use the process controller so that the wafer can be measured in real time while the wafer is being etched and an etching depth can be effectively controlled (Page 4, para. 3).
Conclusion
The prior art made of record and not relied upon is considered pertinent to applicant's disclosure. Okuuchi et al. (WO 2011013356 A1) is cited to teach a cleaning step using SC1 and an oxidation process using ozone.
Any inquiry concerning this communication or earlier communications from the examiner should be directed to SEAN MICHAEL DAVIS whose telephone number is (571)270-5775. The examiner can normally be reached M-F: 7:30am - 5:00pm.
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If attempts to reach the examiner by telephone are unsuccessful, the examiner’s supervisor, Yara Green can be reached at (571) 270-3035. The fax phone number for the organization where this application or proceeding is assigned is 571-273-8300.
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/SMD/Examiner, Art Unit 2893
/YARA B GREEN/Supervisor Patent Examiner, Art Unit 2893
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