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 .
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and the fee set forth in 37 CFR 1.17(e) has been timely paid, the finality of the previous Office action has been withdrawn pursuant to 37 CFR 1.114.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 August 28, 2026 has been entered.
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, 8-13, 21, and 23-27 are rejected under 35 U.S.C. 103 as being unpatentable over US 2017/0108768 A1 to Hsu et al. (hereinafter “Hsu ‘768” – previously cited reference) in further view of US 2018/0031965 A1 to Jindal (hereinafter “Jindal” – previously cited reference).
Regarding claim 1, Hsu ‘768 discloses an extreme ultraviolet (EUV) mask, comprising:
a substrate (EUV mask 100 having substrate 101; paragraph [0014]);
a reflective multilayer stack on the substrate (reflective multilayer 102 disposed upon substrate 101; Fig. 3A; paragraph [0017]);
a multi-layer capping feature on the reflective multilayer stack (multilayered capping layers 104, 302 structure disposed upon reflective multilayer 102; Fig. 3A; paragraph [0040]), the multi-layer capping feature including a first capping layer physically contacting a topmost surface of the reflective multilayer stack and including a material containing an element having a first solid carbon solubility (capping layer 104 may contact top surface reflective multilayer 102 and may comprise ruthenium with another chemical element having an atomic number less than that of ruthenium inherently having a first solid carbon solubility; Fig. 3A; paragraphs [0038], [0040]) and a second capping layer including a material containing an element having a second solid carbon solubility, the first solid carbon solubility being different from the second solid carbon solubility (capping layer 302 may comprise ruthenium with another chemical element having an atomic number less than that of ruthenium inherently having a second solid carbon solubility different than the first; paragraphs [0038], [0040]); and
a patterned absorber layer on the multi-layer capping feature (patterning absorption layer 106 disposed upon multilayered capping layers 104, 302 structure; Fig. 3A; paragraphs [0019], [0040]).
Hsu ‘768 fails to disclose a second capping layer physically contacting the first capping layer, wherein the first capping layer comprises iridium (Ir), platinum (Pt), palladium (Pd) or alloys thereof.
However, Jindal discloses a second capping layer physically contacting the first capping layer (capping layer 422 in physical contact with layer 420a which may be made from Pt or Ir and may have a thickness of 1-5 nm; Fig. 5; paragraphs [0074], [0076]), wherein the first capping layer comprises iridium (Ir), platinum (Pt), palladium (Pd) or alloys thereof (layer 420a may be made from Pt or Ir and may have a thickness of 1-5 nm; Fig. 5; paragraphs [0074], [0076]).
Hsu ‘768 and Jindal are both considered to be analogous to the claimed invention because they are in the same field of EUV masks having capping layers to prevent contamination. Therefore, it would have been obvious to a person having ordinary skill in the art before the effective filing date of the claimed invention to have modified Hsu ‘768 to incorporate the teaching of Jindal in order to potentially provide fine control of the EUV transmission characteristics, prevention of carbon contamination, and enhanced oxidation and corrosion resistance.
Regarding claim 2, Hsu ‘768 in view of Jindal discloses the EUV mask of claim 1. Hsu ‘768 further discloses wherein the first solid carbon solubility is less than the second solid carbon solubility (ruthenium has a lesser solid carbon solubility value, approximately 0.25 atomic percent at 1000 degrees C, than those materials having a smaller atomic number, such as chromium with an approximate value of 0.75 atomic percent at 1000 degrees C; paragraphs [0038], [0040]).
Regarding claim 3, Hsu ‘768 in view of Jindal discloses the EUV mask of claim 2. Hsu ‘768 further discloses wherein the first solid carbon solubility of the element of the material of the first capping layer at 1000° C is less than 1.6 atomic percent (ruthenium has a lesser solid carbon solubility value, approximately 0.25 atomic percent at 1000 degrees C; paragraph [0038]).
Regarding claim 4, Hsu ‘768 in view of Jindal discloses the EUV mask of claim 1. Hsu ‘768 further discloses wherein the second solid carbon solubility of the element of the material of the second capping layer at 1000° C is less than the first solid carbon solubility of the element of the material of the first capping layer at 1000° C (capping layer 302 may utilize ruthenium having a lesser solid carbon solubility value, approximately 0.25 atomic percent at 1000 degrees C, than the capping layer 104 which may utilize a material having a smaller atomic number, such as chromium with an approximate value of 0.75 atomic percent at 1000 degrees C; paragraphs [0038], [0040]).
Regarding claim 5, Hsu ‘768 in view of Jindal discloses the EUV mask of claim 1. Hsu ‘768 further discloses wherein an element of the material of the first capping layer has an EUV extinction coefficient for EUV radiation having a wavelength of 13.5 nm that is different from an EUV extinction coefficient for EUV radiation having a wavelength of 13.5 nm of an element of the material of the second capping layer (EUV radiation at 13.5 nm may be incident upon capping layers, where capping layer 104 may utilize ruthenium which inherently has a different EUV extinction coefficient for such EUV radiation than a material having a smaller atomic number used in the capping layer 302; paragraphs [0015], [0033], [0040]).
Regarding claim 8, Hsu ‘768 in view of Jindal discloses the EUV mask of claim 1. Hsu ‘768 further discloses wherein the first solid carbon solubility of the first capping layer at 1000° C is less than 1.6 atomic % (ruthenium has a lesser solid carbon solubility value, approximately 0.25 atomic percent at 1000 degrees C; paragraph [0038]).
Regarding claim 9, Hsu ‘768 in view of Jindal discloses the EUV mask of claim 1. Hsu ‘768 further discloses wherein the second solid carbon solubility of the second capping layer at 1000° C is less than 1.6 atomic % (capping layer 302 may utilize materials having a smaller atomic number than ruthenium, such as chromium with an approximate value of 0.75 atomic percent at 1000 degrees C; paragraphs [0038], [0040]).
Regarding claim 10, Hsu ‘768 in view of Jindal discloses the EUV mask of claim 1. Hsu ‘768 further discloses wherein the second capping layer comprises Cr, Rh, Zn, Zr, Ag, Cd or alloys thereof (capping layer 302 may utilize materials having a smaller atomic number than ruthenium, such as chromium; paragraphs [0038], [0040]).
Regarding claim 11, Hsu ‘768 in view of Jindal discloses the EUV mask of claim 1. Hsu ‘768 further discloses wherein the material of the second capping layer is selected from CrRh, CrZn, CrZr, CrAg, CrCd, RhZr, RhZn, RhAg, RhCd, ZnZr, ZnAg, ZnCd, ZrAg, ZrCd and AgCd (capping layer 302 may utilize materials having a smaller atomic number than ruthenium, such as chromium and zirconium; paragraphs [0038], [0040]).
Regarding claim 12, Hsu ‘768 in view of Jindal discloses the EUV mask of claim 1. Hsu ‘768 further discloses wherein portions of the first capping layer are exposed in trenches of the patterned absorber layer and second capping layer (portions of capping layer 104 exposed in trenches of patterning absorption layer 106 and capping layer 302 as shown in Fig. 3A).
Regarding claim 13, Hsu ‘768 in view of Jindal discloses the EUV mask of claim 1. Hsu ‘768 further discloses wherein portions of the first capping layer are exposed in trenches of the patterned absorber layer and no portions of the second capping layer are exposed in the trenches of the patterned absorber layer (portions of capping layer 104 exposed in trenches of patterning absorption layer 106 and capping layer 302 as shown in Fig. 3A).
Hsu fails to disclose wherein the second capping layer is exposed in the trenches of the absorber layer and no portions of the first capping layer are exposed in the trenches of the patterned absorber layer.
However, it would have been obvious to one of ordinary skill in the art before the effective filing date to modify Hsu to use the second capping layer, instead of the first capping layer, to be exposed in the trenches of the absorber layer, because simply substituting the first capping layer of Hsu to be the second capping layer would yield the same resulting structure which is a predictable result.
Regarding claim 21, Hsu ‘768 discloses an extreme ultraviolet (EUV) mask, comprising:
a substrate (EUV mask 100 having substrate 101; paragraph [0014]);
a reflective multilayer stack on the substrate (reflective multilayer 102 disposed upon substrate 101; Fig. 3A; paragraph [0017]);
a multi-layer capping feature on the reflective multilayer stack (multilayered capping layers 104, 302 structure disposed upon reflective multilayer 102; Fig. 3A; paragraph [0040]), the multi-layer capping feature including a first capping layer physically contacting a topmost surface of the reflective multilayer stack and including an element having a first EUV extinction coefficient for EUV radiation having a wavelength of 13.5 nm and a second patterned capping layer including an element having a second EUV extinction coefficient for EUV radiation having a wavelength of 13.5 nanometers, the first EUV extinction coefficient being different from the second EUV extinction coefficient (EUV radiation at 13.5 nm may be incident upon capping layers, where capping layer 104 may contact top surface reflective multilayer 102 and may utilize ruthenium which inherently has a different EUV extinction coefficient for such EUV radiation than a material having a smaller atomic number used in the capping layer 302; Fig. 3A; paragraphs [0015], [0033], [0040]), and the second patterned capping layer comprises ruthenium (Ru), niobium (Nb), silicon (Si), chromium (Cr) or alloys thereof (capping layer 302 may comprise ruthenium with another chemical element having an atomic number less than that of ruthenium, such as chromium; paragraphs [0038], [0040]); and
a patterned absorber layer on the multi-layer capping feature (patterning absorption layer 106 disposed upon multilayered capping layers 104, 302 structure; Fig. 3A; paragraphs [0019], [0040]).
Hsu ‘768 fails to disclose a second capping layer physically contacting the first capping layer, wherein the first capping layer comprises iridium (Ir), platinum (Pt), palladium (Pd) or alloys thereof.
However, Jindal discloses a second capping layer physically contacting the first capping layer (capping layer 422 in physical contact with layer 420a which may be made from Pt or Ir and may have a thickness of 1-5 nm; Fig. 5; paragraphs [0074], [0076]), wherein the first capping layer comprises iridium (Ir), platinum (Pt), palladium (Pd) or alloys thereof (layer 420a may be made from Pt or Ir and may have a thickness of 1-5 nm; Fig. 5; paragraphs [0074], [0076]).
Hsu ‘768 and Jindal are both considered to be analogous to the claimed invention because they are in the same field of EUV masks having capping layers to prevent contamination. Therefore, it would have been obvious to a person having ordinary skill in the art before the effective filing date of the claimed invention to have modified Hsu ‘768 to incorporate the teaching of Jindal in order to potentially provide fine control of the EUV transmission characteristics, prevention of carbon contamination, and enhanced oxidation and corrosion resistance.
Regarding claim 23, Hsu ‘768 in view of Jindal discloses the EUV mask of claim 21. Hsu ‘768 further discloses wherein the first capping layer and the second patterned capping layer independently have a thickness ranging from 0.5 nm to 5 nm (thickness of the capping layers may be within a range of about 2 to 7 nanometers; paragraph [0018]).
Regarding claim 24, Hsu ‘768 discloses an extreme ultraviolet (EUV) mask, comprising:
a substrate (EUV mask 100 having substrate 101; paragraph [0014]);
a reflective multilayer stack on the substrate (reflective multilayer 102 disposed upon substrate 101; Fig. 3A; paragraph [0017]);
a first capping layer on the reflective multilayer stack, the first capping layer in physical contact with a topmost surface of the reflective multilayer stack (capping layer 104 disposed upon top surface of reflective multilayer 102; Fig. 3A; paragraph [0040]);
a second patterned capping layer on the first capping layer (capping layer 302 is patterned and disposed upon reflective multilayer 102 and capping layer 104 as shown in Fig. 3A; paragraph [0040]),
a patterned absorber layer on the second patterned capping layer (patterning absorption layer 106 disposed upon multilayered capping layers 104, 302 structure; Fig. 3A; paragraphs [0019], [0040]),
wherein the first capping layer includes a material including an element having a first carbon solubility at 1000° C that is different from a second carbon solubility at 1000° C of an element of a material of the second patterned capping layer (capping layer 302 may utilize ruthenium having a lesser solid carbon solubility value, approximately 0.25 atomic percent at 1000 degrees C, than the capping layer 104 which may utilize a material having a smaller atomic number, such as chromium with an approximate value of 0.75 atomic percent at 1000 degrees C; paragraphs [0038], [0040]), the first capping layer comprises an alloy selected from CrRh, CrZn, CrZr, CrAg, CrCd, RhZr, RhZn, RhAg, RhCd, ZnZr, ZnAg, ZnCd, ZrAg, ZrCd, and AgCd (capping layer 104 may utilize materials having a smaller atomic number than ruthenium, such as chromium and zinc; paragraphs [0038], [0040]), and the second patterned capping layer comprises ruthenium niobium (RuNb), ruthenium dioxide (RuO2), ruthenium niobium oxide (RuNbO), niobium pentoxide (Nb2O5), or chromium oxynitride (CrON) (capping layer 302 may comprise ruthenium with another chemical element having an atomic number less than that of ruthenium, such as oxygen; paragraphs [0038], [0040]); and
wherein the second patterned capping layer and the patterned absorber layer comprise a pattern of openings (capping layer 302 and patterning absorption layer 106 are patterned to have openings revealing capping layer 104 as shown in Fig. 3A; paragraph [0040]).
Hsu ‘768 fails to disclose the second patterned capping layer in physical contact with the first capping layer; and the patterned absorber layer being a topmost layer of the EUV mask.
However, Jindal discloses the second patterned capping layer in physical contact with the first capping layer (capping layer 422 in physical contact with layer 420a which may be made from Pt or Ir and may have a thickness of 1-5 nm; Fig. 5; paragraphs [0074], [0076]); and the patterned absorber layer being a topmost layer of the EUV mask (absorber layer 310, 420 topmost layer of EUV mask 302, 400; Figs. 4-5).
Hsu ‘768 and Jindal are both considered to be analogous to the claimed invention because they are in the same field of EUV masks having capping layers to prevent contamination. Therefore, it would have been obvious to a person having ordinary skill in the art before the effective filing date of the claimed invention to have modified Hsu ‘768 to incorporate the teaching of Jindal in order to potentially provide high EUV contrast between absorbing layers and multilayer/capping layers, fine control of the EUV transmission characteristics, prevention of carbon contamination, and enhanced oxidation and corrosion resistance.
Regarding claim 25, Hsu ‘768 in view of Jindal discloses the EUV mask of claim 24. Hsu ‘768 further discloses wherein the first carbon solubility at 1000° C that is less than the second carbon solubility at 1000° C (ruthenium has a lesser solid carbon solubility value, approximately 0.25 atomic percent at 1000 degrees C, than those materials having a smaller atomic number, such as chromium with an approximate value of 0.75 atomic percent at 1000 degrees C; paragraphs [0038], [0040]).
Regarding claim 26, Hsu ‘768 in view of Jindal discloses the EUV mask of claim 24. Hsu ‘768 further discloses wherein the first carbon solubility at 1000° C that is greater than the second carbon solubility at 1000° C (capping layer 302 may utilize ruthenium having a lesser solid carbon solubility value, approximately 0.25 atomic percent at 1000 degrees C, than the capping layer 104 which may utilize a material having a smaller atomic number, such as chromium with an approximate value of 0.75 atomic percent at 1000 degrees C; paragraphs [0038], [0040]).
Regarding claim 27, Hsu ‘768 in view of Jindal discloses the EUV mask of claim 24. Hsu ‘768 further discloses wherein the first capping layer comprises CrRh, CrZr, CrCd, RhZr, RhZn, RhAg, RhCd, ZnZr, ZnCd, ZrAg, ZrCd or AgCd (capping layer 104 may utilize materials having a smaller atomic number than ruthenium, such as chromium and zirconium; paragraphs [0038], [0040]).
Claims 6-7 and 22 are rejected under 35 U.S.C. 103 as being unpatentable over Hsu ‘768 as modified by Jindal in further view of US 2019/0146331 A1 to Lin et al. (hereinafter “Lin ‘331” – previously cited reference).
Regarding claim 6, Hsu ‘768 in view of Jindal discloses the EUV mask of claim 5. Hsu ‘768 fails to disclose wherein the EUV extinction coefficient for EUV radiation having a wavelength of 13.5 nm of the element of the material of the first capping layer is between 0 and 0.1.
However, Lin ‘331 discloses wherein the EUV extinction coefficient for EUV radiation having a wavelength of 13.5 nm of the element of the material of the first capping layer is between 0 and 0.1 (capping layer 210 utilizing absorptive materials to absorb EUV light having wavelength of 10-15 nm with an extinction coefficient of 0.01 to 0.04; paragraphs [0015], [0020]-[0021]).
Hsu ‘768 and Lin ‘331 are both considered to be analogous to the claimed invention because they are in the same field of EUV masks. Therefore, it would have been obvious to a person having ordinary skill in the art before the effective filing date of the claimed invention to have modified Hsu ‘768 to incorporate the teaching of Lin ‘331 in order to potentially provide preservation of mask reflectivity, reduced thickness sensitivity, and enhanced durability without sacrificing optics.
Regarding claim 7, Hsu ‘768 in view of Jindal discloses the EUV mask of claim 5. Hsu ‘768 fails to disclose wherein the EUV extinction coefficient for EUV radiation having a wavelength of 13.5 nm of the element of the material of the second capping layer is between 0 and 0.1.
However, Lin ‘331 discloses wherein the EUV extinction coefficient for EUV radiation having a wavelength of 13.5 nm of the element of the material of the second capping layer is between 0 and 0.1 (capping layer 210 utilizing absorptive materials to absorb EUV light having wavelength of 10-15 nm with an extinction coefficient of 0.01 to 0.04; paragraphs [0015], [0020]-[0021]).
Hsu ‘768 and Lin ‘331 are both considered to be analogous to the claimed invention because they are in the same field of EUV masks. Therefore, it would have been obvious to a person having ordinary skill in the art before the effective filing date of the claimed invention to have modified Hsu ‘768 to incorporate the teaching of Lin ‘331 in order to potentially provide preservation of mask reflectivity, reduced thickness sensitivity, and enhanced durability without sacrificing optics.
Regarding claim 22, Hsu ‘768 in view of Jindal discloses the EUV mask of claim 21. Hsu ‘768 fails to disclose wherein the first EUV extinction coefficient or the second EUV extinction is between 0 and 0.1.
However, Lin ‘331 discloses wherein the first EUV extinction coefficient or the second EUV extinction is between 0 and 0.1 (capping layer 210 utilizing absorptive materials to absorb EUV light having wavelength of 10-15 nm with an extinction coefficient of 0.01 to 0.04; paragraphs [0015], [0020]-[0021]).
Hsu ‘768 and Lin ‘331 are both considered to be analogous to the claimed invention because they are in the same field of EUV masks. Therefore, it would have been obvious to a person having ordinary skill in the art before the effective filing date of the claimed invention to have modified Hsu ‘768 to incorporate the teaching of Lin ‘331 in order to potentially provide preservation of mask reflectivity, reduced thickness sensitivity, and enhanced durability without sacrificing optics.
Response to Arguments
Applicant's arguments filed August 28, 2026 have been fully considered. Applicant submitted substantive amendments to claims 1 and 24 with corresponding arguments. As to independent claims 1, 21, and 24, Applicant first asserts that Examiner uses impermissible hindsight reconstruction using Applicant’s disclosure as a roadmap, but does not cite to any part of Applicant’s specification nor to Examiner’s statements to support this conclusory statement. Applicant next asserts that Jindal’s absorber layer cannot be considered a capping layer. However, Applicant ignores the fact that an absorber layer can function as a capping layer and vice versa. This is evidenced by the overlap in materials used for the absorber layers and capping layers. For example, Applicant asserts that an absorber layer, which may be made from a list of materials that have significant overlap with the capping layer materials disclosed in Applicant’s specification, cannot be considered a capping layer because Jindal labels it as an absorber layer. This argument is not persuasive. Further, Applicant asserts that Jindal’s absorber layer cannot function as a capping layer because it does not contact the reflective multilayer stack, but Applicant does not take issue with Hsu ‘768 (Applicant’s own prior art) labeling element 302 of Fig. 3A as a capping layer despite it not contacting the reflectively multilayer stack. Examiner maintains that a layer having the same shape, position, and material composition as a capping layer disclosed in Applicant’s specification will have the same functionality as a capping layer in the art. Finally, Applicant asserts that Hsu ‘768 does not disclose the alloys amended into claim 24. However, paragraph [0038] of Hsu ‘768 discloses that the secondary material may be selected from elements having an atomic number smaller than ruthenium. A singular material selected from a plurality of elements encompasses those elements being an alloy to form the singular material. While Applicant amended claim 27 to remove some alloys from the list based upon the disclosure of Jindal, Hsu ‘768 still discloses at least one of the alloys on the list. Therefore, Hsu ‘768 in view of Jindal discloses the amended claim language.
Conclusion
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/IAN DEGRASSE/Examiner, Art Unit 2818
/JEFF W NATALINI/Supervisory Patent Examiner, Art Unit 2818
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