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 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) 1-3, 5-6, 9, 11-15, 20, 23 and 25-27 is/are rejected under 35 U.S.C. 103 as being unpatentable over TAKATSUKI (Pub. No.: US 2020/0111675) in view of Mullick (Pub. No.: US 2019/0189456).
Re claim 1, TAKATSUKI teaches a method comprising:
providing a feature on a substrate (101), the feature comprising a metal surface (102) having a layer of metal oxide (102a, FIG. 5A, ¶ [0048]) formed thereon and a dielectric surface; and
exposing the feature to a metal halide (“a chemical etching is promoted by using at least one of the WF6, WCl5, WCl6”, FIG. 5B, [0050]) to remove the layer of metal oxide (102a) from the metal surface (102) wherein exposing the feature to a metal halide [0060] to remove the layer of metal oxide [0059] from the metal surface comprises exposing the feature to a plurality of cycles (ALD, [0079]) without an intervening reducing agent pulse (note that “.The step of removing the tungsten oxide film 102a is a chemical reaction-based etching process. For example, when the WF.sub.6 gas is supplied as a halogen-containing gas”, ¶ [0067])
TAKATSUKI fails to teach wherein each cycle comprises a dose of a metal halide followed by a pulse of an inert gas during or between the cycles of the plurality of cycles.
Mullick teaches wherein exposing the feature to a metal halide ([0027]-[0028]) to remove the layer of metal oxide (130, [0020]) from the metal surface comprises exposing the feature to a plurality of cycles, wherein each cycle comprises a dose of a metal halide followed by a pulse of an inert gas (“The metal halide and/or the reductant may be exposed to the substrate with a carrier gas or diluent gas. Suitable carrier or diluent gases include, without limitation, Ar, N.sub.2, He, Ne, Kr, Xe and mixtures thereof”, [0031], note that the reductant is used to etch residue 140, [0030]) during or between the cycles of the plurality of cycles (“the method comprises multiple cycles”, [0032]).
It would have been obvious for a person of ordinary skill in the art before the effective filing date of the claim invention to include the above said teaching for the purpose of etching oxidized metal films that provide less etch residue as taught by Mullick, [0002].
Re claim 2, in the combination, TAKATSUKI teaches the method of claim 1, further comprising filling the feature with a conductive material (210, FIG. 5C, [0074]).
Re claim 3, in the combination, TAKATSUKI teaches the method of claim 2, wherein the conductive material (210, FIG. 5C) directly contacts the metal surface (102) and the dielectric surface (110) without an interposed layer.
Re claim 5, in the combination, TAKATSUKI teaches the method of claim 2, wherein filling the feature with a conductive material comprises depositing bulk conductive material without depositing a nucleation layer (from the bottom up to form 210, [0074]).
Re claim 6, in the combination, TAKATSUKI teaches the method of claim 1, wherein filling the feature comprises an atomic layer deposition or chemical vapor deposition process, including plasma enhanced or thermal processes, to deposit bulk conductive material [0079].
Re claim 9, in the combination, TAKATSUKI teaches the method of any of claim 2, wherein exposing the feature to the metal halide and filling the feature with a conductive material are performed in the same chamber (100, FIG. 2).
Re claim 11, in the combination, TAKATSUKI teaches the method of any of claim 2, wherein exposing the feature to the metal halide and filling the feature with a conductive material are performed in different chambers (swapping among chambers 11 to 14 as shown in FIG. 1, [0021]).
Re claim 12, in the combination, TAKATSUKI teaches the method of claim 1, wherein the conductive material is selected from molybdenum (Mo), ruthenium (Ru), tungsten (W), iridium (ir), chromium (Cr), cobalt (Co), and titanium nitride (TiN) (210, FIG. 5C, [0074]).
Re claim 13, in the combination, Mullick teaches the method of claim 1, wherein the metal surface is a one of a titanium nitride (TiN) surface (115, [0019]), a molybdenum nitride (MoNx) surface, a tungsten nitride (WN) surface, a tungsten carbon nitride (WCxNy) surface, a tungsten carbide (WCx) surface, a titanium aluminum carbide (TiAlxCy) surface, or a tantalum nitride (TaN) surface.
Re claim 14, in the combination, TAKATSUKI teaches the method of any of claim 1 wherein the metal of the metal halide is one of Mo, W, Cr, Ti, Ta, and vanadium (V) [0094].
Re claim 15, in the combination, TAKATSUKI teaches the method of any of claim 1 wherein the metal halide is one of tungsten hexafluoride (WF6), tungsten hexachloride (WCl6), tungsten pentachloride (WCl5), tungsten hexabromide (WBr6) [0094].
Re claim 20, in the combination, TAKATSUKI teaches the method of claim 1, further comprising performing a reducing treatment (with H2, [0068) to remove residual halogen (SOCl2) after removing the layer of metal oxide.
Re claim 23, in the combination, TAKATSUKI teaches the method of claim 2, wherein the bulk conductive layer is deposited using the metal halide (WF6, [0067]).
Re claim 25, TAKATSUKI teaches a method comprising:
providing a feature on a substrate (101), the feature comprising a metal-containing surface (102) having a layer of oxide (102a, FIG. 5A) formed thereon and a dielectric surface (110); and
exposing the feature to a metal halide [0060]; wherein exposing the feature to a metal halide comprises exposing the feature including the dielectric surface to a plurality of cycles to remove the layer of oxide from the metal-containing surface, wherein each cycle comprises a dose of molybdenum pentachloride (MoCls) followed by a pulse of inert gas without an intervening reducing agent pulse (note that “.The step of removing the tungsten oxide film 102a is a chemical reaction-based etching process. For example, when the WF6 gas is supplied as a halogen-containing gas”, ¶ [0067] and the reducing gas is using ONLY in the case of SOCl2, [0069], in this case we are using the WF6 gas, therefore, we don’t need the reducing H2 gas) during or between the cycles of the plurality of cycles.
TAKATSUKI fails to teach wherein each cycle comprises a dose of a metal halide followed by a pulse of an inert gas during or between the cycles of the plurality of cycles and wherein an amount of oxide etched is linearly related to the number of cycles.
Mullick teaches wherein exposing the feature to a metal halide ([0027]-[0028]) to remove the layer of metal oxide (130, [0020]) from the metal surface comprises exposing the feature to a plurality of cycles, wherein each cycle comprises a dose of a metal halide followed by a pulse of an inert gas during or between the cycles of the plurality of cycles (“The metal halide and/or the reductant may be exposed to the substrate with a carrier gas or diluent gas. Suitable carrier or diluent gases include, without limitation, Ar, N.sub.2, He, Ne, Kr, Xe and mixtures thereof”, [0031], note that the reductant is used to etch residue 140, [0030]) during or between the cycles of the plurality of cycles (“the method comprises multiple cycles”, [0032]), and wherein an amount of oxide etched is linearly related to the number of cycles (“the method comprises multiple cycles.”, [0032]).
It would have been obvious for a person of ordinary skill in the art before the effective filing date of the claim invention to include the above said teaching for the purpose of etching oxidized metal films that provide less etch residue as taught by Mullick, [0002].
Re claim 26, in the combination, Mullick teaches the method of claim 25, wherein exposing the feature to a metal halide (102a) further comprises removing some metal of the metal-containing surface (102, FGI. 5A → 5B).
Re claim 27, in the combination, Mullick teaches the method of claim 25, wherein exposing the feature to a metal halide (130) is done without removing any metal of the metal-containing surface (115).
Claim(s) 16-19 and 22 is/are rejected under 35 U.S.C. 103 as being unpatentable over TAKATSUKI.
Re claims 16-19, TAKATSUKI teaches all the limitations of claim 1 and wherein exposing the feature to a metal halide to remove the layer of metal oxide (102a, FIGS. 5A → 5B, [0093]) from the metal surface comprises exposing the feature to a plurality of cycles (ALD process, [0092]).
TAKATSUKI fails to teach the limitation of claim 16/17/18/19.
However, TAKATSUKI teaches wherein the metal halide is one of molybdenum hexafluoride (MoF6) and molybdenum pentachloride (MoCl5) (claim 16), wherein the metal halide is one of niobium pentachloride (NbCl5) and niobium pentabromide (NbBr5) (claim 17); wherein the metal halide is one of tantalum pentafluoride (TaF5) and tantalum pentachloride (TaCl5) (claim 18); and wherein the metal halide is one of vanadium pentafluoride (VF5), chromium pentafluoride (CrF5), and titanium tetrachloride (TiCl4) (claim 20) (“The tungsten oxide film is an example of the metal oxide film. In this experiment, ClF3, WCl5, and WCl6 gases were used as the other halogen gases”, FIG. 2, ¶ [0045]).
It would have been obvious for a person of ordinary skill in the art before the effective filing date of the claim invention to include the above said teaching for the purpose of effecting remove the oxide material using the halogen containing gas as taught by TAKATSUKI, Abstract.
Moreover, TAKATSUKI does not specifically disclose the specific material as teaching in claim 17-19.
However, it would have been obvious to one having ordinary skill in the art at the time of the invention was made to include the above said teaching since it has been held to be within the general skill of a worker in the art to select a known material on the basis of its suitability for the intended use as a matter of obvious design choice. In re Leshin, 277 F.2d 197, 125 USPQ 416.
Re claim 22, in the combination, TAKATSUKI teaches the method of claim 2, wherein the plurality of cycles (in order to achieve a desired thickness of step 462 of FIG. 4B).
TAKATSUKI differs from the claim invention by not disclosing wherein the plurality of cycles is at least 20 cycles.
However, Applicant has not disclosed that the ranges are for particular unobvious purpose, produce an unexpected result, or are otherwise critical. Therefore, it would have been obvious to one having ordinary skill in the art at the time the invention was made to include the above said teaching, since it has been held that where the general conditions of a claim are disclosed in the prior art, discovering the optimum or workable ranges involves only routine skill in the art. In re Aller, 220 F.2d 454, 456, 105 USPQ 233, 235 (CCPA 1955) (Claimed process which was performed at a temperature between 40°C and 80°C and an acid concentration between 25% and 70% was held to be prima facie obvious over a reference process which differed from the claims only in that the reference process was performed at a temperature of 100°C and an acid concentration of 10%.); see also Peterson, 315 F.3d at 1330, 65 USPQ2d at 1382 ("The normal desire of scientists or artisans to improve upon what is already generally known provides the motivation to determine where in a disclosed set of percentage ranges is the optimum combination of percentages."); In re Hoeschele, 406 F.2d 1403, 160 USPQ 809 (CCPA 1969) (Claimed elastomeric polyurethanes which fell within the broad scope of the references were held to be unpatentable thereover because, among other reasons, there was no evidence of the criticality of the claimed ranges of molecular weight or molar proportions.). For more recent cases applying this principle, see Merck & Co. Inc. v. Biocraft Laboratories Inc., 874 F.2d 804, 10 USPQ2d 1843 (Fed. Cir.), cert. denied, 493 U.S. 975 (1989); In re Kulling, 897 F.2d 1147, 14 USPQ2d 1056 (Fed. Cir. 1990); and In re Geisler, 116 F.3d 1465, 43 USPQ2d 1362 (Fed. Cir. 1997).
Claim(s) 24 is/are rejected under 35 U.S.C. 103 as being unpatentable over TAKATSUKI in view of Mullick and further in view of Thombare (Pub. No.: US 2018/0294187).
Re claim 24, TAKATSUKI teaches a method comprising:
providing a feature on a substrate, the feature comprising a metal surface (102) having a layer of metal oxide (102a) formed thereon and a dielectric surface (110); and exposing the feature to a metal halide to remove the layer of metal oxide from the metal surface (FIG. 5A → 5B),
wherein exposing the feature to a metal halide to remove the layer of metal oxide from the metal surface comprises exposing the feature to a plurality of cycles, wherein each cycle comprises a dose of pulse WCl5 ([0058], note that this is performed under the ALD process, [0079]) without an intervening reducing agent pulse (note that “The step of removing the tungsten oxide film 102a is a chemical reaction-based etching process. For example, when the WF.sub.6 gas is supplied as a halogen-containing gas”, ¶ [0067]), and
wherein the bulk conductive layer is deposited using a ruthenium precursor and a reducing agent (of carbon, [0075]).
TAKATSUKI fails to teach wherein each cycle comprises a dose of a MoCl5 followed by a pulse of an inert gas during or between the cycles of the plurality of cycles and wherein the bulk conductive layer is deposited using a molybdenum precursor.
Mullick teaches wherein exposing the feature to a metal halide ([0027]-[0028]) to remove the layer of metal oxide (130, [0020]) from the metal surface comprises exposing the feature to a plurality of cycles, wherein each cycle comprises a dose of a metal halide followed by a pulse of an inert gas (“The metal halide and/or the reductant may be exposed to the substrate with a carrier gas or diluent gas. Suitable carrier or diluent gases include, without limitation, Ar, N.sub.2, He, Ne, Kr, Xe and mixtures thereof”, [0031], note that the reductant is used to etch residue 140, [0030]) during or between the cycles of the plurality of cycles (“the method comprises multiple cycles”, [0032]).
It would have been obvious for a person of ordinary skill in the art before the effective filing date of the claim invention to include the above said teaching for the purpose of etching oxidized metal films that provide less etch residue as taught by Mullick, [0002].
Moreover, TAKATSUKI/Mullick fails to teach wherein the bulk conductive layer is deposited using a molybdenum precursor; and after removing the layer of metal oxide, raising a temperature of the substrate and depositing a bulk conductive layer on the metal surface.
Thombare teaches wherein the bulk conductive layer is deposited using a molybdenum precursor (456, FIG. 4B), and depositing a bulk conductive layer on the metal surface with HIGH temperature (“In operation 406, the substrate is exposed to a Mo-containing precursor at a substrate temperature T2….. Examples of temperatures are 500° C. to 700° C”, [0054]).
It would have been obvious for a person of ordinary skill in the art before the effective filing date of the claim invention to include the above said teaching for the purpose of reducing high resistivity for thinner films as taught by Thombare, [0003].
Finally, after the combining of TAKATSUKI and Thombare would teach after removing the layer of metal oxide, raising a temperature of the substrate and depositing a bulk conductive layer on the metal surface because TAKATSUKI teaches after removing the layer of metal oxide at 200 ºC or lower (using the etching gas as CiF3, [0062]) and Thombare teaches depositing a bulk conductive layer on the metal surface with HIGH temperature (“In operation 406, the substrate is exposed to a Mo-containing precursor at a substrate temperature T2….. Examples of temperatures are 500° C. to 700° C”, [0054] and “the Mo layer 108 may be deposited on a tungsten (W) or W-containing growth initiation layer, FIG. 1A, [0021]).
Response to Arguments
Applicant's arguments filed 07/30/2026 have been fully considered but they are not persuasive.
In response to Applicant’s argument:
“Contrary to the Office Action, Tatsuki does not teach or suggest "a plurality of cycles" in exposing the metal oxide to WF6. As explained in the prior response, the ALD reference at [0079] pertains to the subsequent tungsten deposition step, not the metal oxide removal step of [0067]. The Office Action's reliance on [0079] to supply this limitation for the removal step is not supported by Tatsuki's actual disclosure - it imports a teaching from an unrelated process step and attributes it to a step where it does not appear.
A rejection under § 103 must rest on the reference's actual teachings, not on an unfounded inference that conflates disparate disclosures. See MPEP § 2142 (Office bears the burden of establishing a prima facie case based on the teachings of the prior art); § 2143 (rejection must be supported by "articulated reasoning with some rational underpinning," not conclusory assertion) (quoting KSR Int'l Co. v. Teleflex Inc., 550 U.S. 398 (2007)). Because Tatsuki's ALD disclosure at [0079] does not describe the metal oxide removal step of [0067], it cannot supply the "plurality of cycles" limitation as applied by the Office.
The Office Action acknowledges that Takatsuki "fails to teach wherein each cycle comprises a dose of metal halide followed by a pulse of inert gas." (Office Action, page 4). It relies on Thombare for this element, alleging that Thombare teaches "exposing the feature to a metal halide to remove the layer of metal oxide" using a plurality of cycles "wherein each cycle comprises a dose of a metal halide followed by a pulse of inert gas." Figure 4B and paragraphs [0058]-[0061], [0066], and [0068] are cited. (Final Office Action, page 4).”, page 5.
The Examiner respectfully submits that Mullick, paragraph [0032] discloses “Exposure of the substrate to the metal halide and the reductant can be referred to as one cycle. In some embodiments, the method comprises multiple cycles”.
For the above reasons, it is believed that the rejections should be sustained.
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 TONY TRAN whose telephone number is (571)270-1749. The examiner can normally be reached Monday-Friday, 8AM-5PM, EST.
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/TONY TRAN/Primary Examiner, Art Unit 2893
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