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 Objections
Claim 10 is objected to because of the following informalities: line 2 of the claim contains the phrase, “is used to complete fill of the first feature,” which is grammatically incorrect. Appropriate correction is required.
The examiner believes the phrase should read: is used to completely fill the first feature. The examiner has interpreted the claim in this manner.
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.
Claim 5 recites the limitation, “the reducing agent flow rate is ramped during the ramp down stage.” It is unclear to the examiner as to which way the reducing agent flow rate is ramping. Is it ramping up or down? For purposes of examination, the examiner has interpreted claim 5 to mean that the reducing agent flow rate is ramping down.
Claim 16 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.
Claim 16 recites the limitation, “the reducing agent flow rate is ramped during the ramp up stage.” It is unclear to the examiner as to which way the reducing agent flow rate is ramping. Is it ramping up or down? For purposes of examination, the examiner has interpreted claim 16 to mean that the reducing agent flow rate is ramping up.
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 1-5, 8, 9, and 18 are rejected under 35 U.S.C. 103 as being obvious over Ba et al. (WO 2020/028587 A1, hereinafter “Ba”) in view of Murakami et al. (USPN 6,169,032 B1, hereinafter “Murakami”).
In reference to claim 1, Ba discloses a similar method. Fig. 1A-1D and 4 of Ba disclose a method which comprises providing a substrate (103) having a feature (101) to be filled with a metal (tungsten) in a chamber. Ba discloses (p. 11, paragraph 39) that a metal precursor (tungsten containing precursor) and a reducing agent (silane, diborane) are flowed into the chamber to deposit metal (tungsten) in the feature (101) in a chemical vapor deposition (CVD) operation. Ba discloses (p. 14, paragraph 55) that the metal precursor flow rate is decreased from a first flow rate to a second flow rate. Ba does not explicitly disclose that the metal precursor flow rate is decreased from a first flow rate to a second flow rate in a ramp down manner. However Murakami discloses that gradually reducing or ramping down flow rates of gases into the chamber during CVD prevents the problem of stress applied to the underlying semiconductor substrate which ultimately prevents crystal defects and distortion in the semiconductor substrate (column 2, lines 13-19, column 9, lines 30-38). In view of Murakami, it would therefore be obvious to ramp down the flow rate of the metal/tungsten precursor.
With regard to claim 2, in the method of Ba constructed in view of Murakami, fig. 4 of Ba discloses a second stage in the form of additional tungsten deposition stage (405); it is understood that the metal precursor flow rate for this stage is constant.
In reference to claim 3, in the method of Ba constructed in view of Murakami, fig. 4 of Ba discloses a tungsten deposition stage (403) prior to the ramp down of the metal/tungsten precursor stage; it is understood that the metal/tungsten precursor flow rate for this stage is constant.
With regard to claim 4, as noted above Ba discloses the use of a reducing agent (p. 11, paragraph 39); it is understood that the reducing agent flow rate is constant. Thus in the method of Ba constructed in view of Murakami, the reducing agent flow rate is constant during the ramp down stage.
So far as understood in claim 5, Ba does not disclose that the reducing agent is ramped down during the ramp down stage. However Murakami discloses that gradually reducing or ramping down flow rates of gases into the chamber during CVD prevents the problem of stress applied to the underlying semiconductor substrate which ultimately prevents crystal defects and distortion in the semiconductor substrate (column 2, lines 13-19, column 9, lines 30-38). In view of Murakami, it would therefore be obvious to ramp down the flow rate of the reducing agent.
In reference to claim 8, fig. 1B of Ba shows that the feature (101) comprises a constriction (115). In the method of Ba constructed in view of Murakami, a stage prior to the ramp down stage is used to fill a portion of the feature (101) below the constriction (115).
With regard to claim 9, in the method of Ba constructed in view of Murakami, the ramp down stage is used to fill the constricted portion (115) of the feature (101).
In reference to claim 18, Ba discloses the use of an apparatus which comprises a process chamber with a pedestal support and a showerhead (p. 16, paragraphs 65- 66, p. 17, paragraph 69). It is understood that at least one gas line directs gases to the showerhead. Ba discloses the use of a controller having instructions to control its activities (p. 17, paragraph 69); the method of Ba constructed in view of Murakami (as discussed above with regard to claim 1) is implemented by the instructions.
Claims 6 and 7 are rejected under 35 U.S.C. 103 as being obvious over Ba in view of Murakami as applied to claim 1 above and further in view of Wang et al. (United States Patent Application Publication No. US 2016/0343612 A1, hereinafter “Wang”).
In reference to claim 6, Ba does not disclose that an inhibition treatment to inhibit metal deposition is performed prior to the CVD operation. However fig. 6 of Wang discloses performing an inhibition treatment to inhibit metal deposition prior to the CVD operation (p. 9, paragraph 94). Wang further discloses that the treatment leads to a reduction of voids in the deposited layer (p. 9, paragraph 94) which is desirable in the art (p. 1, paragraph 3). In view of Wang, it would therefore be obvious to perform an inhibition treatment to inhibit metal deposition prior to the CVD operation in the method of Ba constructed in view of Murakami.
With regard to claim 7, fig. 6 of Wang shows that the inhibited area (655) for metal deposition is near the feature opening,
Claims 12, 14-16, and 19 are rejected under 35 U.S.C. 103 as being obvious over Ba in view of Otsuki et al. (United States Patent Application Publication No. US 2003/0147075 A1, hereinafter “Otsuki”).
In reference to claim 12, Ba discloses a similar method. Fig. 1A-1D and 4 of Ba disclose a method which comprises providing a substrate (103) having a feature (105) to be filled with a metal (tungsten) in a chamber. Ba discloses (p. 11, paragraph 39) that a metal precursor (tungsten containing precursor) and a reducing agent (silane, diborane) are flowed into the chamber to deposit metal (tungsten) in the feature (105) in a chemical vapor deposition (CVD) operation. Ba discloses (p. 12, paragraph 43) that the metal precursor flow rate is increased from a first flow rate to a second flow rate. Ba does not explicitly disclose that the metal precursor flow rate is increased from a first flow rate to a second flow rate in a ramp up manner. However Otsuki discloses that gradually increasing or ramping up flow rates of gases into the chamber prevents warping of the semiconductor substrate on which the CVD process is being performed (p. 16, paragraph 241). In view of Otsuki, it would therefore be obvious to ramp up the flow rate of the metal/tungsten precursor.
With regard to claim 14, in the method of Ba constructed in view of Otsuki, fig. 4 of Ba discloses a second stage in the form of additional tungsten deposition stage (405); it is understood that the metal precursor flow rate for this stage is constant.
In reference to claim 15, as noted above Ba discloses the use of a reducing agent (p. 11, paragraph 39); it is understood that the reducing agent flow rate is constant. Thus in the method of Ba constructed in view of Otsuki, the reducing agent flow rate is constant during the ramp up stage.
So far as understood in claim 16, Ba does not explicitly disclose that the reducing agent flow rate is ramped up during the ramp up stage. However Otsuki discloses that gradually increasing or ramping up flow rates of gases into the chamber prevents warping of the semiconductor substrate on which the CVD process is being performed (p. 16, paragraph 241). In view of Otsuki, it would therefore be obvious to ramp up the flow rate of the reducing agent.
With regard to claim 19, Ba discloses the use of an apparatus which comprises a process chamber with a pedestal support and a showerhead (p. 16, paragraphs 65-66, p. 17, paragraph 69). It is understood that at least one gas line directs gases to the showerhead. Ba discloses the use of a controller having instructions to control its activities (p. 17, paragraph 69); the method of Ba constructed in view of Otsuki (as discussed above with regard to claim 12) is implemented by the instructions.
Claim 17 is rejected under 35 U.S.C. 103 as being obvious over Ba in view of Otsuki as applied to claim 12 above and further in view of Wang.
In reference to claim 17, Ba does not disclose that an inhibition treatment to inhibit metal deposition is performed prior to the CVD operation. However fig. 6 of Wang discloses performing an inhibition treatment to inhibit metal deposition prior to the CVD operation (p. 9, paragraph 94). Wang further discloses that the treatment leads to a reduction of voids in the deposited layer (p. 9, paragraph 94) which is desirable in the art (p. 1, paragraph 3). In view of Wang, it would therefore be obvious to perform an inhibition treatment to inhibit metal deposition prior to the CVD operation in the method of Ba constructed in view of Otsuki.
Allowable Subject Matter
Claims 10, 11, and 13 are objected to as being dependent upon a rejected base claim, but would be allowable if rewritten in independent form including all of the limitations of the base claim and any intervening claims.
The following is a statement of reasons for the indication of allowable subject matter: in the examiner’s opinion, it would not be obvious to implement a method which comprises filling a feature in a substrate with a metal in a chamber by flowing a metal precursor and a reducing agent in a chemical vapor deposition operation in combination with the suggested flow rates and the required feature structures to be filled as described by the applicant in claims 10 and 13.
Conclusion
Any inquiry concerning this communication or earlier communications from the examiner should be directed to KEVIN QUINTO whose telephone number is (571)272-1920. The examiner can normally be reached Monday-Friday, 9-5:30.
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/KEVIN QUINTO/Examiner, Art Unit 2893
/Britt Hanley/Supervisory Patent Examiner, Art Unit 2893
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