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 .
The response of the applicant has been read and given careful consideration. Rejection of the previous office action not repeated below are withdrawn based upon the amendments and arguments of the applicant. Responses to the arguments of the applicant are presented after the first rejection they are directed to.
The following is a quotation of the appropriate paragraphs of 35 U.S.C. 102 that form the basis for the rejections under this section made in this Office action:
A person shall be entitled to a patent unless –
(a)(1) the claimed invention was patented, described in a printed publication, or in public use, on sale, or otherwise available to the public before the effective filing date of the claimed invention.
(a)(2) the claimed invention was described in a patent issued under section 151, or in an application for patent published or deemed published under section 122(b), in which the patent or application, as the case may be, names another inventor and was effectively filed before the effective filing date of the claimed invention.
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 1-8, 12,13,16 and 22-23 are rejected under 35 U.S.C. 103 as being unpatentable over Ikebe et al. 20170038673, in view of Ikebe et al. JP 2018-031982.
Ikebe et al. 20170038673 in example 1 teaches an EUV mask including a substrate (12) provided with a reflective multilayer (13), a 2.5 nm RuNb protective/capping layer, a RuO2 antidiffusion surface layer formed in the Ru based protective layer, a 5 nm TaN phase shift film, a 46 nm CrOCN film, and a 5 nm silicon dioxide etch mask. This mask blanks is then pattered using a photoresist where the SiO2 films is patterned using CF4 etch gas, the CrCON layer is patterns using a Cl2/O2 etch gas and the TaN film is etched with a Cl2 etch gas. After the patterning the SiO2 is removed by etching [0078-0095]. Example 3 is similar [0099-0107]. A representative material for the etching mask film may include silicon (Si), or a material formed by adding oxygen, nitrogen, carbon, or hydrogen to silicon (Si). Specifically, it includes Si, SiO, SiN, SiON, SiC, SiCO, SiCN, SiCON, or the like. As described in the examples below, the formation of the etching mask film allows the thickness of the resist film to be reduced, which is advantageous in the pattern refinement. For example, if the material for the outermost surface layer of the phase-shift film 16 is to be etched with a chlorine-based gas (which may contain oxygen), the material which has a resistance to the chlorine-based gas and can be etched with the fluorine-based gas is selected for the etching mask film. If the material for the outermost surface layer of the phase-shift film 16 is to be etched with the fluorine-based gas (which may contain oxygen), the material which has a resistance to the fluorine-based gas and can be etched with the chlorine-based gas (which may contain oxygen) is selected for the etching mask film. In this case, a material which can be etched with the chlorine-based gas free of oxygen is preferably selected, in terms of thinning of the resist film [0067]. There is no particular limitation on a material for the phase-shift film 16 as long as it has a function to absorb the EUV light and can be removed by, for example, etching. In this embodiment, in view of etching selectivity, etc., a tantalum simple substance, or a tantalum-based material containing tantalum is used. The tantalum-based material may be a TaB alloy containing Ta and B, a TaSi alloy containing Ta and Si, a Ta alloy containing Ta and other transition metals (e.g., Pt, Pd, and Ag), or a tantalum-based compound made by adding N, O, H, or C to the Ta metal or its alloy [0054]. Since Ta has a high absorption coefficient for the EUV light, and may be easily dry etched with a chlorine-based gas or fluorine-based gas, it is a phase-shift film material having excellent processability. Further, by adding B, Si, Ge, etc. to Ta, an amorphous material may be easily obtained, and the smoothness of the phase-shift film 16 may be improved. The addition of N or O to Ta improves the resistance to oxidation in the phase-shift film 16, which gives an effect of improvement in stability over time [0057]. As further clarified in the description of examples below, the phase-shift film 16 includes one made of the tantalum-based material layer alone, as well as one formed by laminating the tantalum-based material layer and other material layers. Specifically, other material layers are a chromium-based material layer and ruthenium-based material layer. The chromium-based material may be a Cr simple substance, a Cr alloy containing Cr and other transition metals (e.g., Pt, Pd, and Ag), or a chromium-based compound made by adding N, O, H, C, etc. to the Cr metal or Cr alloy. The ruthenium-based material may be a Ru metal simple substance, or a Ru alloy containing Ru and metal such as Nb, Zr, Y, B, Ti, La, Mo, Co, and Re. It may be a ruthenium-based compound made by adding N, O, H, C, etc. to the Ru metal or its alloy. If the phase-shift film 16 is formed to have a laminated structure of the tantalum-based material layer and other material layers (other material layers are laminated onto the tantalum-based material layer), it is preferably formed continuously without exposure to the atmosphere from the beginning to the end of film formation. This may prevent an oxidized layer (tantalum oxide layer) from being formed on a surface of the tantalum-based material layer 161 (thereby eliminating the step for removing the tantalum oxide layer). There is no particular limitation on the order and amount of lamination for the tantalum-based material layer and chromium-based material layer in the phase-shift film 16. For example, the phase-shift film 16 may have a two-layer structure of Ta/Cr, a two-layer structure of Cr/Ta, a three-layer structure of Ta/Cr/Ta, a three-layer structure of Cr/Ta/Cr, a four-layer structure of Ta/Cr/Ta/Cr, a four-layer structure of Cr/Ta/Cr/Ta, a four-layer structure of Ta/Ta/Cr/Cr, a four-layer structure of Cr/Cr/Ta/Ta, etc., and the other structures, wherein the order of the Ta and Cr layers are as viewed from the substrate 12 side. However, as shown in examples below, it is more preferable that the material adjacent to the anti-diffusion layer 15 is the tantalum-based material layer and that the outermost surface layer of the phase-shift film 16 is the chromium-based material layer. This is because such a configuration causes the chromium-based material layer to also have a function as an anti-oxidation film for the tantalum-based material layer (the oxidation and reduction in etching rate caused if Ta is provided as the uppermost layer may be inhibited). Further, if the chromium-based material layer is provided as the outermost surface layer of the phase-shift film 16, it is more preferably made of a material containing carbon, in particular, CrC, CrCO, CrCN, CrCON, CrCH, CrCOH, CrCHN, and CrCONH, in terms of chemical resistance upon mask cleaning. Ta and Cr include their nitrides, oxides, or alloys in addition to single metals, and thus, Ta layers and Cr layers in the phase-shift film 16 may not comprise the same material or composition, respectively. There is also no particular limitation on the order and amount of lamination for the tantalum-based material layer and ruthenium-based material layer in the phase-shift film 16. For example, the phase-shift film 16 may have a two-layer structure of Ta/Ru, a three-layer structure of Ta/Ru/Ta, a four-layer structure of Ta/Ru/Ta/Ru, a four-layer structure of Ta/Ta/Ru/Ru, etc., and the other structures, wherein the order of the Ta and Ru layers are as viewed from the substrate 12 side. However, as shown in examples below, it is more preferable that the material adjacent to the anti-diffusion layer 15 is the tantalum-based material layer and that the outermost surface layer of the phase-shift film 16 is the ruthenium-based material layer. Such a configuration causes the ruthenium-based material layer to also have a function as an anti-oxidation film for the tantalum-based material layer. Ta and Ru include their nitrides, oxides, or alloys in addition to single metals, and thus, Ta layers and Ru layers in the phase-shift film 16 may not comprise the same material or composition, respectively [0057-0060].
Ikebe et al. JP 2018-031982 (machine translation attached) teaches EUV maskblanks which are patterned. The etching mask film is formed of a material having etching selectivity with respect to the uppermost layer of the multilayer reflective film 13 and capable of being etched with an etching gas with respect to the absorber film 15 (having no etching selectivity). Specifically, the etching mask film is formed of a material containing Cr or Ta, for example. Examples of the material containing Cr include Cr metal alone and Cr-based compounds obtained by adding one or more elements selected from elements such as O, N, C, H, and B to Cr. Materials containing Ta include Ta metal alone, TaB alloy containing Ta and B, Ta alloy containing Ta and other transition metals (for example, Hf, Zr, Pt, and W), Ta metal, and their alloys And Ta-based compounds in which N, O, H and / or C are added. Here, when the absorber film 15 contains Ta, a material containing Cr is selected as a material for forming the etching mask film. Moreover, when the absorber film 15 contains Cr, it is preferable to select a material containing Ta as a material for forming the etching mask film. The thickness of the etching mask film is preferably 5 nm or more from the viewpoint of ensuring the function as a hard mask. In the manufacturing process of the reflective mask 20, the etching mask film is removed simultaneously with the absorber film 15 by the fluorine-based gas used in the etching process of the absorber film 15. Therefore, it is preferable that the etching mask film has substantially the same thickness as the absorber film 15. Considering the film thickness of the absorber film 15, the film thickness of the etching mask film is 5 nm or more and 20 nm or less, preferably 5 nm or more and 15 nm or less [0102,0104]
Ikebe et al. 20170038673 does not exemplify a mask blank where the etch mask (hardmask) is a Ta compound. The 5 nm TaN phase shift layer in examples 1 or 3 is considered to meet the buffer layer requirement.
With respect to claims 1-3,5-8,12-13, 15,16 and 22-23, it would have been obvious to one skilled in the art at the time of invention to modify examples 1 or 3 of Ikebe et al. 20170038673 by replacing the 5 nm SiO2 hardmask with a 6-15 nm thickness of TaN based upon the disclosed equivalence as an etch mask for Cr containing absorber in Ikebe et al. JP 2018-031982 at [0102,0104]with the added benefit that the same sputtering target could be used for both the phase shift (buffer) and the hardmask layers. Further, it would have been obvious to pattern the resulting mask blank using the processes of these claims, including the disclosed etchant gasses and/or to use the EUV mask for its disclosed function, specifically EUV exposure of resists.
With respect to claims 1-3,5-8,12-13, 15,16 and 22-23, it would have been obvious to one skilled in the art at the time of invention to modify examples 1 or 3 of Ikebe et al. 20170038673 by replacing the 5 nm SiO2 hardmask with a 6-15 nm thickness of Ta are containing B, C, N and/or O based upon the disclosed equivalence as an etch mask for Cr containing absorber in Ikebe et al. JP 2018-031982 at [0102,0104]. Further, it would have been obvious to pattern the resulting mask blank suing the processes of these claims, including the disclosed etchant gasses and/or to use the EUV mask for its disclosed function, specifically EUV exposure of resists.
With respect to claims 1-8,12-13, 15,16 and 22-23, it would have been obvious to one skilled in the art at the time of invention to modify examples 1 or 3 of Ikebe et al. 20170038673 by replacing the 5 nm TaN phases shift layer with a 5 nm thickness of TaO, TaOB, or TaON based upon the disclosed equivalence at [0054] of Ikebe et al. 20170038673 and replacing the 5 nm SiO2 hardmask with a 6-15 nm thickness of Ta are containing B, C, N and/or O based upon the disclosed equivalence as an etch mask for Cr containing absorber in Ikebe et al. JP 2018-031982 at [0102,0104]. Further, it would have been obvious to pattern the resulting mask blank suing the processes of these claims, including the disclosed etchant gasses.
The applicant argues that the prior art does not teach the Ta etch mask/hardmask in contact with the Cr layer in Abe et al. A new rejection is drafted which addresses this issue. While Ikebe et al. 20170038673 does not exemplify the Ta hardmasks, the use of a Ta hardmask over a Cr absorber layer is known in the art as evidenced by Ikebe et al. JP 2018-031982 at [0102,0104].
In the response of 1/30/2026, the applicant argues that because there is a RuO2 anti-diffusion layer between the RuNb protective layer and the TaN phase shift layer, the reference does not meet the limitation of the claims which requires the Ta containing (buffer) layer to be in direct contact with the Ru protective layer and the Ru protective layer to be in direct contact with the reflective multilayer. The examiner disagrees, pointing out that the anti-diffusion layer is a surface oxidized portion of the RuNb layer (treated with ozone in the examples) and even if this was not the case, the current claims do not preclude the protective layer being a multilayer based upon the language that the protective layer can be a single layer or can include a stack of three or more layers at [0046] of the instant (substitute) specification.
Claims 1-8, 12-20 and 22-23 are rejected under 35 U.S.C. 103 as being unpatentable over Ikebe et al. 20170038673, in view of Ikebe et al. JP 2018-031982, further in view of Abe et al. JP 2011187746
Abe et al. JP 2011187746 (machine translation attached) in example 1, coats a quartz substrate with a Mo/Si reflective multilayer, a 2.5 nm Ru capping/protective layer, a 10 nm CrN buffer layer, a 40 nm TaBN absorber film, a 15 nm TaBO film and a 10 nm CrN hardmask. This is coated with an electron beam resist, which is patterned and used to mask the etch of the CrN hardmask using Cl2/O2. The resist was removed and the CrN hardmask used to pattern wise etch the TaBO layer with a fluorine gas and the TaBN layer with a chlorine gas. The CrN buffer layer (14) and CrN hardmask are then etched using Cl/O2 [0083-0091]. The thickness of the buffer layer can be 5-15 nm [0076]. The absorber can be Ta, TaB, TaBN and other materials containing Ta as the main component, Cr, Cr as the main component, N, O, and C. A material containing at least one component is used in a thickness range of about 20 nm to 100 nm [0077]. The hardmask layer can be 5-15 nm thick [0080].
The combination of Ikebe et al. 20170038673 and Ikebe et al. JP 2018-031982 does not clearly teach the use of a fluorinated etch with the Ta based materials.
In addition to the basis above, the examiner holds that it would have been obvious to modify the processes of patterning the maskblanks rendered obvious by the combination of Ikebe et al. 20170038673 and Ikebe et al. JP 2018-031982 by replacing the Cl2 etch gas used to tech the TaN/Ta containing phase shift layer with a fluorinated etch similar to that used in of Ikebe et al. 20170038673 to etch the SiO2 hardmask with a reasonable expectation of success based upon the direction to the use of fluorinated etched in Ikebe et al. 20170038673 at [0057-0060] and the disclosed etch of Ta compounds using fluorine or Cl2 etches in Abe et al. JP 2011187746 at [0083-0091].
The applicant argues that the prior rejection did not teach the use of the etches recited in claims 14. This is clearly addressed in the rejection above, which establishes the equivalence of Cl2 and fluorine etches for Ta containing layers.
In the response of 1/30/2026, the applicant argues that because there is a RuO2 anti-diffusion layer between the RuNb protective layer and the TaN phase shift layer, the reference does not meet the limitation of the claims which requires the Ta containing (buffer) layer to be in direct contact with the Ru protective layer and the Ru protective layer to be in direct contact with the reflective multilayer. The examiner disagrees, pointing out that the anti-diffusion layer a surface oxidized portion of the RuNb layer is a surface oxidized portion of the RuNb layer (treated with ozone in the examples) and even if this was not the case, the current claims do not preclude the protective layer being a multilayer based upon the language that the protective layer can be a single layer or can include a stack of three or more layers at [0046] of the instant specification.
Claims 1-8, 12-20 and 22-23 are rejected under 35 U.S.C. 103 as being unpatentable over Hayashi 20140356770, in view of Ikebe et al. JP 2018-031982.
Hayashi 20140356770 (cited 12/14/2023) in example 1, teaches an EUV mask blank composed of a substrate, a reflective Mo/Si multilayer, a 2.5 nm Ru protective film, a CrN lower absorber layer, a TaPdN upper absorber layer [0197-0217]. Example 5 is similar, but the lower absorber layer is a 10 nm TaPdN film and the upper absorber is a 28 nm CrN film [0221-0222]. Example 6 is similar to example 5,. But the lower absorber is 25 nm of TaPdN and the upper absorber layer is 6 nm or CrN [0223-0224]. However, when the mask blank 1 has the protective layer 13 made of Ru or Ru compound as a constituent material, a combination in which the upper layer 14a is a TaPd-based film and the lower layer 14b is a Cr-based film is preferable for the following reason. There is. As described above, a chlorine-based gas is used as an etching gas when the Cr-based film dry etching process is performed. The dry etching process using a chlorine-based gas causes little damage to the protective layer 13 made of Ru or Ru compound. Therefore, when the lower layer 14b is a Cr film, it is possible to reduce damage to the protective layer 13 made of Ru or Ru compound immediately below it as a constituent material [0104]. It is disclosed that the TaPd based films are etched with a fluorine gas which the Cr based films are resistant to etching and in this case the Cr based material acts as a hardmask [0105]. The use of hard masks, that is, a layer of a material resistant to the etching conditions of the absorption layer (or the absorption layer and the low reflection layer when the low reflection layer is formed on the absorption layer) may be formed. . By forming such a hard mask layer, the absorption layer (the low reflection layer is formed on the absorption layer) under the etching conditions of the absorption layer (the absorption layer and the low reflection layer when the low reflection layer is formed on the absorption layer) is formed. If formed, the etching selectivity between the absorption layer and the low reflection layer) and the hard mask layer, specifically, the absorption layer (if the low reflection layer is formed on the absorption layer, the absorption layer and the low reflection layer) The ratio of the etching rate of the absorption layer under the etching conditions of the layer) (the etching rate of the absorption layer and the low reflection layer when a low reflection layer is formed on the absorption layer) and the etching rate of the hard mask layer By increasing the thickness, the resist can be thinned is disclosed [0193]. Since the absorption layer 14 of the present invention is composed of the upper layer 14a and the lower layer 14b having different constituent materials, the types of etching gases used in the dry etching process are different. In the case of a Cr-based film containing Cr as a main component, a chlorine-based gas (Cl .sub.2 , BCl .sub.3 ) is preferably used as an etching gas. On the other hand, a TaPd-based film containing Pd as a main component is preferably used as an etching gas using a fluorine-based gas (CF .sub.4 , CF .sub.3 H). However, in the case of a TaPd-based film, the etching rate when the dry etching process is performed is ½ that of a conventional Ta-based film (for example, TaN, TaNH, TaBN) that contains Ta as a main component and does not contain Pd. It is slow with about 1/6. For this reason, when the thickness of the TaPd-based film exceeds 36 nm, a slow etching rate becomes a problem when a dry etching process is performed for the purpose of forming a pattern on the absorption layer 14 [0101]. one of the upper layer and the lower layer being a Cr film containing chromium (Cr) as the main component and containing at least one of oxygen (O) and nitrogen (N), and the other being a TaPd film containing tantalum (Ta) and palladium (Pd) as the main components, and containing at least one of O and N [0020]
Hayashi 20140356770 does not exemplify a mask blank where the etch mask (hardmask) is a Ta compound. The 10 nm TaPdN layer in example 5 is considered to meet the buffer layer requirement.
With respect to claims 1-3,5,7-8,12-13, 15,16 and 22-23, it would have been obvious to one skilled in the art at the time of invention to modify example 5 of Hayashi 20140356770 by adding a hardmask to allow the resist used to be thinner [0193] and to use a 10-15 nm thickness of TaPdN based upon the disclosed equivalence as an etch mask for Cr containing absorber in Ikebe et al. JP 2018-031982 at [0102,0104] with the added benefit that the same sputtering target could be used for both the buffer and the hardmask layers. Further, it would have been obvious to pattern the resulting mask blank using the processes disclosed, including the disclosed etchant gasses and/or to use the EUV mask for its disclosed function, specifically EUV exposure of resists.
With respect to claims 1-5,7-8,12-18,20 and 22-23, it would have been obvious to one skilled in the art at the time of invention to modify example 5 of Hayashi 20140356770 by replacing the TaPdN layer with TaPdO or TaPdON as discussed at [0020], adding a hardmask to allow the resist used to be thinner [0193] and to use a 10-15 nm thickness of TaPdO or TaPdON based upon the disclosed equivalence as an etch mask for Cr containing absorber in Ikebe et al. JP 2018-031982 at [0102,0104] with the added benefit that the same sputtering target could be used for both the buffer and the hardmask layers. Further, it would have been obvious to pattern the resulting mask blank using the processes disclosed including the disclosed etchant gasses and/or to use the EUV mask for its disclosed function, specifically EUV exposure of resists.
With respect to claims 1-3,5,7-8,12-13,15,16 and 22-23, it would have been obvious to one skilled in the art at the time of invention to modify example 5 of Hayashi 20140356770 by adding a hardmask to allow the resist used to be thinner [0193] and to use a 10-15 nm thickness of TaPdN based upon the disclosed equivalence as an etch mask for Cr containing absorber in Ikebe et al. JP 2018-031982 at [0102,0104] with the added benefit that the same sputtering target could be used for both the buffer and the hardmask layers and patterning the TaPd based layers with a CF4 etch and the CrN layer with a Cl2 or BCl3 etch disclosed at [0101] and use ethe resulting EUV mask for its disclosed function, specifically EUV exposure of resists.
With respect to claims 1-5,7-8,12-18,20 and 22-23, it would have been obvious to one skilled in the art at the time of invention to modify example 5 of Hayashi 20140356770 by replacing the TaPdN layer with TaPdO or TaPdON as discussed at [0020], adding a hardmask to allow the resist used to be thinner [0193] and to use a 10-15 nm thickness of TaPdO or TaPdON based upon the disclosed equivalence as an etch mask for Cr containing absorber in Ikebe et al. JP 2018-031982 at [0102,0104] with the added benefit that the same sputtering target could be used for both the buffer and the hardmask layers and patterning the TaPd based layers with a CF4 etch and the CrN layer with a Cl2 or BCl3 etch disclosed at [0101] and use ethe resulting EUV mask for its disclosed function, specifically EUV exposure of resists.
Any inquiry concerning this communication or earlier communications from the examiner should be directed to Martin J Angebranndt whose telephone number is (571)272-1378. The examiner can normally be reached 7-3:30 pm EST.
Examiner interviews are available via telephone, in-person, and video conferencing using a USPTO supplied web-based collaboration tool. To schedule an interview, applicant is encouraged to use the USPTO Automated Interview Request (AIR) at http://www.uspto.gov/interviewpractice.
If attempts to reach the examiner by telephone are unsuccessful, the examiner’s supervisor, Mark F Huff can be reached on 571-272-1385. The fax phone number for the organization where this application or proceeding is assigned is 571-273-8300.
Information regarding the status of published or unpublished applications may be obtained from Patent Center. Unpublished application information in Patent Center is available to registered users. To file and manage patent submissions in Patent Center, visit: https://patentcenter.uspto.gov. Visit https://www.uspto.gov/patents/apply/patent-center for more information about Patent Center and https://www.uspto.gov/patents/docx for information about filing in DOCX format. For additional questions, contact the Electronic Business Center (EBC) at 866-217-9197 (toll-free). If you would like assistance from a USPTO Customer Service Representative, call 800-786-9199 (IN USA OR CANADA) or 571-272-1000.
MARTIN J. ANGEBRANNDT
Primary Examiner
Art Unit 1737
/MARTIN J ANGEBRANNDT/Primary Examiner, Art Unit 1737 February 9, 2026