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 .
Applicant amended Claims 1-2. Applicant cancelled Claims 5-6, 8, 10, and 16-20. Support for the amendments is found in the original filing. No new matter is presented.
Continued Examination Under 37 CFR 1.114
Receipt is acknowledged of a request for continued examination under 37 CFR 1.114, including the fee set forth in 37 CFR 1.17(e) and a submission, filed on 08/24/2026.
Claim Rejections - 35 USC § 112
Claims 11, 12, and 14 are rejected under 35 U.S.C. 112(d) or pre-AIA 35 U.S.C. 112, 4th paragraph, as being of improper dependent form for failing to further limit the subject matter of the claim upon which it depends, or for failing to include all the limitations of the claim upon which it depends.
Claim 1 recites transitional phrase “consisting of.” Claim 1 recites “the hard mask layer consists of chromium (Cr), nitrogen (N), oxygen (O), optionally carbon (C), and optionally boron B), in Lines 12-13. See MPEP § 2113.03 II. According to MPEP § 2111.03 II, (second paragraph), “[a] claim element defined by selection from a group of alternatives (a Markush grouping; see MPEP §§ 2117 and 2173.05(h)) requires selection from a closed group "consisting of" (rather than "comprising" or "including") the alternative members. Abbott Labs. v. Baxter Pharmaceutical Products Inc., 334 F.3d 1274, 1280, 67 USPQ2d 1191, 1196-97 (Fed. Cir. 2003). If the claim element is intended to encompass combinations or mixtures of the alternatives set forth in the Markush grouping, the claim may include qualifying language preceding the recited alternatives (such as "at least one member" selected from the group), or within the list of alternatives (such as "or mixtures thereof"). Id. In the absence of such qualifying language there is a presumption that the Markush group is closed to combinations or mixtures.”
In accordance with the recitation of Claim 1 “consisting of chromium (Cr), nitrogen (N), oxygen (O)…” Claims 11, 12, and 14 do not contain oxygen and therefore fail to further limit Claim 1.
To overcome the resulting 35 U.S.C. 112(d) rejections, Applicant is encouraged to consider amending “consists of” to “selected from the group consisting of” or “at least one member selected from the group consisting of.”
Applicant may cancel the claim(s), amend the claim(s) to place the claim(s) in proper dependent form, rewrite the claim(s) in independent form, or present a sufficient showing that the dependent claim(s) complies with the statutory requirements.
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.
The factual inquiries for establishing a background for determining obviousness under 35 U.S.C. 103 are summarized as follows:
1. Determining the scope and contents of the prior art.
2. Ascertaining the differences between the prior art and the claims at issue.
3. Resolving the level of ordinary skill in the pertinent art.
4. Considering objective evidence present in the application indicating obviousness or nonobviousness.
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 1-4, 7, 9, 11-15, and 21-22 are rejected under 35 U.S.C. 103 as being unpatentable over Sakai et al. US 20150261083 A1 in view of Nam et al. KR 20110059510 A and Nam et al. US 20140004449 A1, further in view of Hayashi et al. US 20100304283 A1.
Regarding Claims 1 and 7, Sakai et al. ‘083 teaches a reflective mask blank for EUV lithography comprising a substrate, and formed in order on that substrate is a reflective layer, protective layer for the reflective layer, absorber film for absorbing EUV light and a hard mask layer [0180, 0182-0183]. The protective layer comprises ruthenium (Ru) and the absorption layer comprises tantalum (Ta) [0008, 0146]. Sakai et al. ‘083 teaches an etching mask or hard mask layer comprised of CrCON [0143], meeting the limitation for the hard mask layer comprising chromium (Cr) and at least one of nitrogen (N) and oxygen (O), and optionally carbon (C).
Regarding the newly amended limitation of Claim 1, Sakai et al. ‘083 further teaches the inclusion of a layer that controls reflectance for a pattern inspection wavelength in Deep Ultraviolet Light [0027] and an inspection wavelength of 193 nm [0190], meeting the limitation of the instant Claims for a low-reflective layer. While referred to as the highly oxidized layer, the layer is formed by oxidizing a TaN absorber layer [0207], and therefore comprises tantalum (Ta) and oxygen (O), and nitrogen (N), meeting the limitations of the instant Claim.
Sakai et al. ‘083 does not expressly teach the substrate has a thermal expansion at 20 °C of 0±0.05×10-7/°C or that the low-reflective layer has a maximum reflectance for low light having a wavelength of around 13.5 nm of 2% or less.
However, Sakai et al. ‘083 teaches exemplary substrates at [0144] of SiO2-TiO2 glass, low thermal expansion glass. Sakai et al. ‘083 does not expressly teach the value of a low thermal expansion. However, persons of ordinary skill in the art would understand SiO2-TiO2 glass to have a low thermal expansion as set forth in [0144] of Sakai et al. ‘083.
Further, Hayashi et al. ‘283 teaches at [0049-0050] reflective mask blank for EUV lithography with a TaN based absorber. The substrate is a SiO2-TiO2 glass with preferably a thermal expansion at 20 °C of 0±0.05×10-7/°C in order to present increased “smoothness, flatness and durability against a cleaning fluid [0050].”
It would have been obvious to one having ordinary skill in the art at the time of filing the invention to use a SiO2-TiO2 glass substrate having the thermal expansion coefficient at 20 °C of 0±0.05×10-7/°C in order to form an EUV mask with increased durability, smoothness, and flatness, based on the teachings of Hayashi et al. ‘283 at [0050].
Sakai et al. ‘083 teaches an etching mask or hard mask layer comprised of CrON [0143], meeting the limitation for the hard mask layer comprising chromium (Cr) and at least one of nitrogen (N) and oxygen (O). The etching mask or hard mask layer of Sakai et al. ‘083 may have a thickness of not more than 7 nm [0041], meeting the limitation of the instant Claims.
Sakai et al. ‘083 does not teach hard mask layer film density.
However, Nam et al. ‘510 teaches a hard mask layer for lithography exposure light wavelengths at 193 nm or 248 nm [0001]. The hard mask is chromium based and can include an “oxide, a nitride, a carbide… oxidized carbonitride [0081].” The hard mask of Nam et al. ‘510 has a film density of 2.0 g / cm3 or more [0068], which specifically comports with the film density of the metal thin film it is disposed on [0068-0069]. Both films may have the same grain size which aligns with the results in Table 2 for a film density of 4.0 g/ cm3 for the metal thin film. This value lies inside the range of the instant Claims from 3.00 g / cm3 to 4.45 g / cm3 and from 3.00 g / cm3 to 4.25 g / cm3. 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).
It would have been obvious to one having ordinary skill in the art at the time of filing the invention to substitute the hard mask film of Sakai et al. ‘083 with the hard mask of Nam et al. ‘510 having a composition meeting the limitations of the instant Claims with a film density of 4.3 g / cm3 in order to increase stability and uniformity of the hard mask film based on the teachings of Nam et al. at [0068-0069]. See MPEP 2143.
Sakai et al. ‘083 modified by Nam et al. ‘510 teaches the limitations set forth above. Sakai et al. ‘083 teaches exemplary chromium-containing materials for its hardmask layer including CrN, CrON hardmask layers but does not expressly teach concentrations for these layers.
However, Nam et al. ‘449 teaches a mask blank for EUV lithography having a chromium-containing hard mask film including CrN, CrON, and CrCN [0016].
One of ordinary skill in the art at the time of filing the invention would look to the art for concentrations of chromium, nitrogen, carbon, and oxygen suitable for a hard mask layer in an EUV mask blank. It would have been obvious to one having ordinary skill in the art at the time of filing the invention to form the hard mask of Sakai et al. ‘083 with the concentrations taught in Nam et al. ‘449 with the reasonable expectation of forming a useful hard mask layer. Nam et al. ‘449 teaches concentrations (Cr: from 30 to 99 at %, N: from 0 to 50 at %, O: 0 to 50 at %, C: from 0 to 20%) at [0030] overlapping the instantly claimed ranges, and meeting the limitations of the instant Claims.
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).
Regarding Claim 2, Sakai et al. ‘083 modified by Nam et al. ‘510, Nam et al. ‘449, and Hayashi et al. ‘283 teaches the limitations set forth above. Sakai et al. ‘083 further teaches the layer meeting the limitation of the instant Claim for a low-reflective layer is formed in direct contact with the absorption layer [0207], meeting the limitations of the instant Claim. Hayashi et al. ‘283 further teaches at [0124] maximum reflectance of the low-reflective layer is of at most 5% at a wavelength of 13.5nm, overlapping the instantly claimed range of 2% or less, meeting the limitations of the instant Claims.
See MPEP 2144.05. In cases where 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).
It would have been obvious to one having ordinary skill in the art at the time of filing the invention to form the low-reflective layer of Sakai et al. ‘083 to have a maximum reflectance of at most 5% in order to increase contrast based on the teachings of Hayashi et al. ‘283 at [0124], meeting the limitations of the instant Claim.
Regarding Claim 3, modified Sakai et al. ‘083 teaches the limitations set forth above, Sakai et al. ‘083 further teaches an etching mask or hard mask layer comprised of CrBOCN [0143], meeting the limitation for the hard mask layer comprising chromium (Cr) and at least one of nitrogen (N) and oxygen (O), wherein at least one of carbon (C) and boron (B) is present in the hard mask layer.
Regarding Claim 4, modified Sakai et al. ‘083 teaches the limitations set forth above. Sakai et al. ‘083 teaches the hard mask layer has a thickness of not more than 7 nm [0041], overlapping the instantly claimed range of 2 nm to 30 nm, meeting the limitation of the instant Claim.
See MPEP 2144.05. In cases where 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).
Regarding Claim 9, Sakai et al. ‘083 modified by Nam et al. ‘510 teaches the limitations set forth above. Sakai et al. ‘083 teaches exemplary chromium-containing materials for its hardmask layer including CrN, CrON, CrCN, CrCON, CrBN, CrBON, CrBCN and CrBOCN hardmask layers but does not expressly teach concentrations for these layers.
However, Nam et al. ‘449 teaches a mask blank for EUV lithography having a chromium-containing hard mask film including CrN, CrON, and CrCN [0016].
One of ordinary skill in the art at the time of filing the invention would look to the art for concentrations of chromium, nitrogen, carbon, and oxygen suitable for a hard mask layer in an EUV mask blank. It would have been obvious to one having ordinary skill in the art at the time of filing the invention to form the hard mask of Sakai et al. ‘083 with the concentrations taught in Nam et al. ‘449 with the reasonable expectation of forming a useful hard mask layer. Nam et al. ‘449 teaches concentrations (Cr: from 30 to 99 at %, N: from 0 to 50 at %, O: 0 to 50 at %, C: from 0 to 20%) at [0030] overlapping the instantly claimed ranges and meeting the limitations of the instant Claim.
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).
Regarding Claims 11-15, Sakai et al. ‘083 modified by Nam et al. ‘510 teaches the limitations set forth above. Sakai et al. ‘083 teaches exemplary chromium-containing materials for its hardmask layer including CrN, CrO, CrON, CrCN, and CrCON [0143], meeting the limitations of the instant Claims.
Regarding Claims 21-22, modified Sakai et al. ‘083 teaches the limitations set forth above. The prior art includes reflective mask blank hard mask layers which overlap and encompass the claimed film densities as they name the same materials as the instant application.
One of ordinary skill in the art at the time of filing the invention would expect durability and etching selectivity to vary with routine experimentation on the reflective mask blank. The values claimed are rendered obvious in light of the prior art, including variations in elemental concentration and changes in film density as expressly taught in Nam et al. ‘510. Chromium-based hard mask layers are known. Further, Nam et al. ‘510 expressly teaches an advantageous hard mask layer having a film density of 2.0 g / cm3 or more [0068], which specifically comports with the film density of the metal thin film it is disposed on [0068-0069]. Both films may have the same grain size which aligns with the results in Table 2 for exemplary film densities of 3.0 g/ cm3 , 3.7 g/ cm3 , and 4.3 g/ cm3 for the metal thin film. Thes values are similar to the instantly claimed hard mask film density range in Claim 21 of from 3.47 g / cm3 to 3.51 g / cm3 and value in Claim 22 of about 4.25 g / cm3 . A prima facie case of obviousness exists where the claimed ranges or amounts do not overlap but are merely close (see MPEP 2144.05(I), second paragraph). The recitation in Nam et al. ‘510 for a hard mask layer having a film density of 2.0 g / cm3 or more [0068],overlaps and encompasses the instantly claimed range in Claim 21 and value in Claim 22. 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).
It would have been obvious to one having ordinary skill in the art at the time of filing the invention to substitute the hard mask film of Sakai et al. ‘083 with the hard mask of Nam et al. ‘510 having a composition meeting the limitations of the instant Claims with a film density meeting the limitations of the instant Claims in order to increase stability and uniformity of the hard mask film based on the teachings of Nam et al. at [0068-0069]. See MPEP 2143.
Response to Arguments
Applicant's arguments filed 08/24/2026 have been fully considered but they are not persuasive.
The claims have been amended to require the low-reflective layer comprises tantalum, oxygen, and nitrogen. Claim 2 has been amended to clarify the low-reflective layer is in direct contact with the absorption layer.
Applicant argues a lack of motivation to modify the layer of Sakai meeting the limitation for a low-reflective layer. However, Sakai et al. ‘083 expressly teaches the inclusion of a layer that controls reflectance for a pattern inspection wavelength in Deep Ultraviolet Light [0027] and an inspection wavelength of 193 nm [0190], meeting the limitation of the instant Claims for a low-reflective layer. While referred to as the highly oxidized layer, the layer of Sakai is formed by oxidizing a TaN absorber layer [0207], and therefore comprises tantalum (Ta) and oxygen (O), and nitrogen (N), meeting the limitations of instant Claim 1. The layer is formed in direct contact with the absorption layer [0207], meeting the limitations of instant Claim 2.
Applicant argues one of ordinary skill in the art would have no reason or modification to modify Sakai et al. ‘083. However, Sakai et al. ‘083 is used for its teachings of EUV reflective mask blanks having the same materials as the instantly claimed materials. As far as modifying or altering the elemental concentrations of the layers, one of ordinary skill would be strongly motivated do so in order to minimize reflective changes and increase the performance and material properties of the mask blank based on the teachings of Nam et al. ‘510 , Nam et al. ‘449, and Hayashi et al. ‘283 in order to form a useful reflective mask blank. See MPEP 2141.01(a) I. “[A] reference need not be from the same field of endeavor as the claimed invention in order to be analogous art.” Bigio, 381 F.3d at 1325, 72 USPQ2d at 1212.
Where the claimed and prior art products are identical or substantially identical in structure or composition, or are produced by identical or substantially identical processes, a prima facie case of either anticipation or obviousness has been established. In re Best, 562 F.2d 1252, 1255, 195 USPQ 430, 433 (CCPA 1977) “When the PTO shows a sound basis for believing that the products of the applicant and the prior art are the same, the applicant has the burden of showing that they are not.” "[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).
Conclusion
The prior art made of record and not relied upon is considered pertinent to applicant's disclosure:
US 10971364 B2 teaches high film density improves the etch selectivity of boron-carbon hard mask films.
US 7638441 B2 teaches a high film density increases etch selectivity of a hydrocarbon polymer hard mask.
US 20070160916 A1 teaches a longstanding practice of preparing a low-reflective layer by oxidizing the absorber layer.
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/M.S.S./Examiner, Art Unit 1737 /Tima M. McGuthry-Banks/Primary Examiner, Art Unit 1733
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