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 .
Continued Examination Under 37 CFR 1.114
A request for continued examination under 37 CFR 1.114, including the fee set forth in 37 CFR 1.17(e), was filed in this application after final rejection. Since this application is eligible for continued examination under 37 CFR 1.114, and the fee set forth in 37 CFR 1.17(e) has been timely paid, the finality of the previous Office action has been withdrawn pursuant to 37 CFR 1.114. Applicant's submission filed on 10 February 2026 has been entered.
Response to Arguments
Applicant has entered the proposed amendments previously presented in the after-final response filed 16 January 2026. No additional arguments were presented with the request for continued examination. The Examiner previously responded to the Applicant’s arguments and the proposed amendments in the advisory action filed 2 February 2026. A summary of the response is provided below.
Applicant’s arguments, see pages 6-7, filed 16 January 2026, with respect to the rejections of claim 1 under 35 U.S.C. 103 as being unpatentable over Deweerd in view of Okamura and claim 9 under 35 U.S.C. 103 as being unpatentable over Deweerd in view of Shoki have been fully considered and are persuasive. The rejections of claim 1 under 35 U.S.C. 103 as being unpatentable over Deweerd in view of Okamura and claim 9 under 35 U.S.C. 103 as being unpatentable over Deweerd in view of Shoki have been withdrawn.
Applicant has made amendments to independent claims 1 and 9. The amendments recite that the coating film has a thickness of 2 nm or more and 6 nm or less, and further states that the thickness of the coating film is within ±2 nm of the average thickness of the coating film. Applicant notes that Deweerd’s coating film has a thickness of less than 2 nm (Deweerd, paragraph 0013). In this regard, the amendment that recites the thickness of the coating film has overcome the rejection made in view of Deweerd and Okamura (for instant claim 1) and the rejection made in view of Deweerd and Shoki (for instant claim 9), due to the combination of Deweerd with either of these references failing to suggest or teach a thickness of the coating film analogue that would fall within the recited range. Therefore, the rejections of claims 1 and 9 based on the modification of Deweerd have been withdrawn.
Applicant’s arguments filed 16 January 2026 with respect to the rejection of claim 1 under 35 U.S.C. 103 as being unpatentable over Yu in view of Okamura and claim 9 under 35 U.S.C. 103 as being unpatentable over Yu in view of Shoki have been fully considered but they are not persuasive.
Applicant notes that Yu’s coating film is between 2.5 nm and 4.0 nm (Yu, paragraph 0053). Applicant argues that neither of Deweerd or Yu teach or suggest a thickness of the coating film is within ±2 nm of the average thickness of the coating film. As noted above, the thickness range recited by the claim amendments overcome the rejections relying upon Deweerd’s disclosure, so the teachings of Deweerd will not be considered for this additional limitation. In terms of Yu’s disclosure, Yu states that the capping layer (analogous to the coating film) has a thickness between 2.5 nm and 4 nm (Yu, paragraph 0053). The disclosure of Yu does not refer to any variances in the thickness of the capping layer. Yu discloses that the capping layer is formed on the reflective multilayer (RML) by physical vapor deposition (PVD) or other suitable technique (Yu, paragraph 0038). Whilst Yu is silent about the thickness of the capping layer being within ±2 nm of the average thickness of the coating film, there is a lack of reason for one having ordinary skill in the art to expect this feature to be absent from Yu’s invention. In other words, one having ordinary skill in the art would expect, absent of evidence to the contrary, that the thickness of the capping layer taught by Yu is reasonably uniform. The instant application utilizes atomic layer deposition (ALD) to form the coating film (see paragraph 0026 of the instant application’s specification). The Examiner recognizes that there are differences between PVD and ALD, and the differences are well documented in the prior art. That being said, the Examiner does not find the Applicant’s argument regarding the thickness variance persuasive. It would be highly unlikely that the capping film of Yu, which has a thickness between 2.5 nm and 4 nm, has a variance in thickness throughout the film that has a magnitude of more than 2 nm. For the capping film of Yu to have a thickness variance of more than 2 nm (in the positive or negative direction), the thickness variance would be at least 50%, which is an extremely high variance to observe in such a precisely applied film. Therefore, even though Yu does not explicitly disclose a thickness variance from the average thickness of ±2 nm, one having ordinary skill in the art would likely interpret the lack of disclosure of a thickness variance when discussing films having a thickness of 2.5 to 4 nm to imply that the variance in thickness from the average is well below this value. Accordingly, the Applicant’s arguments in regards to the rejections based upon the modification of Yu are not found to be persuasive.
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 and 3 are rejected under 35 U.S.C. 103 as being unpatentable over US 20170351169 A1 (hereby referred to as Yu) in view of US 20140186753 A1 (hereby referred to as Okamura).
Regarding Claim 1, Yu discloses a high durability extreme ultraviolet photomask. One embodiment of Yu’s invention is demonstrated by Fig. 4 of Yu (Yu, paragraph 0033). The reflective mask disclosed by Yu comprises a substrate (102), a reflective multilayer (RML, 104), and an absorber layer (108), wherein the absorber layer does not fully cover the reflective multilayer (Yu, paragraph 0033). Over the absorber layer and the reflective multilayer is a capping layer (162) (Yu, paragraph 0033). The capping layer is analogous to the coating film recited by instant claim 1. The capping layer is formed over the absorber layer, but may also be deposited on the sidewalls of the absorber layer (Yu, paragraph 0034). The capping layer may be an alloy containing ruthenium, or may be a titanium, silicon, or zirconium doped by one of oxygen and nitrogen (Yu, paragraph 0034). The capping layer (162) is stated to be equivalent to the capping layer (106) used in other embodiments (Yu, paragraphs 0034). Yu further discloses that the capping layer (106) has a thickness that is designed to provide anti-oxidation and etching resistance without degrading the EUV reflectivity of the mask (Yu, paragraph 0027). The thickness of the capping layer ranges between 2.5 nm and 4 nm (Yu, paragraph 0053), which overlaps with the thickness recited by instant claim 1. Yu does not explicitly disclose a thickness variation of the capping layer. However, the lack of disclosure of a thickness variation of a film having a thickness between 2.5 nm and 4 nm implies that a thickness variation, especially one on the magnitude of more than ±2 nm, is not present within the capping layer. Whilst the extinction coefficient is not explicitly stated by Yu, the capping layer (162) is made up of materials recited by the instant application’s specification to have extinction coefficients below 0.04 (see paragraph 0024 of the instant application’s specification).
However, Yu is silent in regards to the protective capping layer containing at least one of rhodium or tungsten. Okamura teaches a reflective mask blank and method of fabricating the same. The reflective mask blank comprises a substrate, a reflective layer over the substrate, and an absorption pattern over the reflective layer (Okamura, paragraph 0040). A protective layer may be formed over the reflective layer (Okamura, paragraph 0040-0041). The mask blank and a patterned mask obtained from the mask blank are shown in Fig. 1 and 2 of Okamura, respectively (Okamura, paragraph 0039-0040). The protective layer acts to protect the reflective layer from oxidation (i.e. chemical damage) (Okamura, paragraph 0054), meaning its function is analogous to the capping layer of Yu. The protective layer may be formed of silicon (Si), titanium (Ti), ruthenium (Ru), rhodium (Rh), carbon (C), silicon carbide (SiC), or mixtures of these species or their respective nitride, oxide, or boride-derived species (Okamura, paragraph 0054).
Yu and Okamura are analogous art because both references pertain to reflective masks. It would have been obvious to one having ordinary skill in the art before the filing date of the instant application to use rhodium for the protective capping layer, as taught by Okamura, in the mask disclosed by Yu because rhodium is taught to be a functional equivalent to ruthenium (see Okamura, paragraph 0054). Ruthenium (Ru) is one of the suitable materials for the capping layer recited by Yu (see Yu, paragraph 0034), and thus per MPEP 2144.06 II., a prima facie case of obviousness exists. Furthermore, whilst neither Yu nor Okamura explicitly disclose an extinction coefficient, it would be expected by those having ordinary skill in the art that the chromium capping layer would have an extinction coefficient of 0.04 or less because the materials for the mask obtained by combining the teachings of Yu and Okamura are extremely similar or identical to those of the instant application, and thus similar or identical properties would be expected.
Regarding Claim 3, Yu discloses that the absorber layer includes at least one of chromium (Cr), chromium oxide (CrO), titanium nitride (TiN), tantalum nitride (TaN), tantalum (Ta), titanium (Ti), or aluminum-copper (Al—Cu), palladium, tantalum boron nitride (TaBN), aluminum oxide (AlO), molybdenum (Mo), and other suitable materials (Yu, paragraph 0029). Tantalum is utilized as the absorber layer material in a preferred embodiment (Yu, paragraph 0029).
Claim(s) 4-5 and 8 are rejected under 35 U.S.C. 103 as being unpatentable over US 20170351169 A1 (hereby referred to as Yu) in view of US 20140186753 A1 (hereby referred to as Okamura) as applied to claim 1 above, and further in view of US 20120164846 A1 (hereby referred to as HA).
Regarding Claims 4-5 and 8, the combination of Yu and Okamura renders obvious a reflective mask comprising a substrate, a reflective portion, an absorption portion, and a coating film, as discussed above. Yu discloses that the capping layer may be deposited using chemical vapor deposition (CVD) (Yu, paragraph 0046).
However, Yu and Okamura are silent in regards to an atomic layer deposition process and the use of a metal hydride, metal halide, or organometallic compound as the material gas in an ALD process. HA teaches a method of forming a metal oxide hardmask. In the method, HA provides a mask template, which is a substrate with layers formed upon it, and deposits, using atomic layer deposition (ALD), a metal oxide hardmask on the template (HA, paragraph 0020). In the ALD process, a precursor to the metal oxide is provided along with a reactant gas (HA, paragraph 0055). In the example provided by HA, the metal oxide hardmask is a titanium oxide (TiO2), and the precursor chosen is a titanium alkoxide or an alkylamino titanium (HA, paragraph 0055). The precursor, which is a material gas, is an organometallic compound.
Yu, Okamura, and HA are analogous art because each reference pertains to mask manufacturing. It would have been obvious to one having ordinary skill in the art before the filing date of the instant application to use an organometallic material gas in an ALD process, as taught by HA, to produce the mask obtained by combining Yu and Okamura because ALD is a form of chemical vapor deposition that provides films having better mechanical strength properties and chemical resistance (HA, paragraph 0041-0042) and because the use of an organometallic compound can provide a higher film growth rate and a lower steric hindrance, resulting in more adsorption sites for the precursor and thus improving the effectiveness of the ALD process (see HA, paragraph 0055).
Claim(s) 9-10 are rejected under 35 U.S.C. 103 as being unpatentable over US 20170351169 A1 (hereby referred to as Yu) in view of US 20030162005 A1 (hereby referred to as Shoki).
Regarding Claims 9-10, Yu discloses a high durability extreme ultraviolet photomask. One embodiment of Yu’s invention is demonstrated by Fig. 4 of Yu (Yu, paragraph 0033). The reflective mask disclosed by Yu comprises a substrate (102), a reflective multilayer (RML, 104), and an absorber layer (108), wherein the absorber layer does not fully cover the reflective multilayer (Yu, paragraph 0033). Over the absorber layer and the reflective multilayer is a capping layer (162) (Yu, paragraph 0033). The capping layer is analogous to the coating film recited by instant claim 1. The capping layer is formed over the absorber layer, but may also be deposited on the sidewalls of the absorber layer (Yu, paragraph 0034). Yu discloses that the absorber layer includes at least one of chromium (Cr), chromium oxide (CrO), titanium nitride (TiN), tantalum nitride (TaN), tantalum (Ta), titanium (Ti), or aluminum-copper (Al—Cu), palladium, tantalum boron nitride (TaBN), aluminum oxide (AlO), molybdenum (Mo), and other suitable materials (Yu, paragraph 0029). Tantalum is utilized as the absorber layer material in a preferred embodiment (Yu, paragraph 0029). The capping layer may be an alloy containing ruthenium, or may be a titanium, silicon, or zirconium doped by one of oxygen and nitrogen (Yu, paragraph 0034). The capping layer (162) is stated to be equivalent to the capping layer (106) used in other embodiments (Yu, paragraphs 0034). Yu further discloses that the capping layer (106) has a thickness that is designed to provide anti-oxidation and etching resistance without degrading the EUV reflectivity of the mask (Yu, paragraph 0027). The thickness of the capping layer ranges between 2.5 nm and 4 nm (Yu, paragraph 0053), which overlaps with the thickness recited by instant claim 9. Yu does not explicitly disclose a thickness variation of the capping layer. However, the lack of disclosure of a thickness variation of a film having a thickness between 2.5 nm and 4 nm implies that a thickness variation, especially one on the magnitude of more than ±2 nm, is not present within the capping layer. Whilst the extinction coefficient is not explicitly stated by Yu, the capping layer (162) is made up of materials recited by the instant application’s specification to have extinction coefficients below 0.04 (see paragraph 0024 of the instant application’s specification). Therefore, the capping layer disclosed by Yu satisfies the requirements recited by instant claim 9, due to the extinction coefficient being an inherent property of the material used.
However, Yu is silent in regards to the absorption layer containing at least one of tin, indium, nickel, osmium, tungsten, or tellurium. Shoki teaches a reflection type mask blank and a reflection mask produced from the same. The reflection mask comprises a substrate, a reflective multilayer, and an absorber film (Shoki, paragraph 0030). A protective layer may further be included in the mask structure to protect the reflective multilayer from oxidation (Shoki, paragraph 0030 and 0037). Thus, the protective layer is analogous to the protective layer of Deweerd. The absorber layer may be formed of a material containing tantalum (Ta) as the main metal component (Shoki, paragraph 0093). The absorber layer may also be formed of materials such as SiO2, C, Ru, SiON, Al2O3, WN, TiN, and the like (Shoki, paragraph 0093). The compound WN is tungsten nitride.
Yu and Shoki are analogous art because both references pertain to reflective photomasks. It would have been obvious to one having ordinary skill in the art before the filing date of the instant application to use a tungsten-based compound, as taught by Shoki, in the absorber layer disclosed by Yu because tungsten is taught to be a functional equivalent to tantalum-based compounds for use in light absorbing layers for reflective photomasks (Shoki, paragraph 0093). Yu utilizes tantalum-based absorber layers (see Yu, paragraph 0029), and thus per MPEP 2144.06 II., a prima facie case of obviousness exists.
Claim(s) 11-13 are rejected under 35 U.S.C. 103 as being unpatentable over US 20170351169 A1 (hereby referred to as Yu) in view of US 20030162005 A1 (hereby referred to as Shoki) as applied to claim 9 above, and further in view of US 20120164846 A1 (hereby referred to as HA).
Regarding Claims 11-13, the combination of Yu and Shoki renders obvious a reflective mask comprising a substrate, a reflective portion, an absorption portion, and a coating film, as discussed above. Yu discloses that the capping layer may be deposited using chemical vapor deposition (CVD) (Yu, paragraph 0046).
However, Yu and Shoki are silent in regards to an atomic layer deposition process and the use of a metal hydride, metal halide, or organometallic compound as the material gas in an ALD process. HA teaches a method of forming a metal oxide hardmask. In the method, HA provides a mask template, which is a substrate with layers formed upon it, and deposits, using atomic layer deposition (ALD), a metal oxide hardmask on the template (HA, paragraph 0020). In the ALD process, a precursor to the metal oxide is provided along with a reactant gas (HA, paragraph 0055). In the example provided by HA, the metal oxide hardmask is a titanium oxide (TiO2), and the precursor chosen is a titanium alkoxide or an alkylamino titanium (HA, paragraph 0055). The precursor, which is a material gas, is an organometallic compound.
Yu, Shoki, and HA are analogous art because each reference pertains to mask manufacturing. It would have been obvious to one having ordinary skill in the art before the filing date of the instant application to use an organometallic material gas in an ALD process, as taught by HA, to produce the mask obtained by combining Yu and Shoki because ALD is a form of chemical vapor deposition that provides films having better mechanical strength properties and chemical resistance (HA, paragraph 0041-0042) and because the use of an organometallic compound can provide a higher film growth rate and a lower steric hindrance, resulting in more adsorption sites for the precursor and thus improving the effectiveness of the ALD process (see HA, paragraph 0055).
Conclusion
The prior art made of record and not relied upon is considered pertinent to applicant's disclosure. US 20170038671 A1 (hereby referred to as Takai) teaches a capping layer formed on an EUV reflective mask that has a uniform thickness (Takai, paragraph 0065). US 20070081229 A1 (hereby referred to as Shiraishi) teaches uniform thickness capping layers formed on EUV reflective mirrors. Takai and Shiraishi provide teaching that capping layers of uniform thickness (i.e. the thickness is within ±2 nm of the average thickness of the capping layer) are commonplace in the art of EUV reflective masks.
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/JAYSON D COSGROVE/Examiner, Art Unit 1737
/JONATHAN JOHNSON/Supervisory Patent Examiner, Art Unit 1734