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. The amendment to the specification are approved. Rejection of the previous action not repeated below are withdrawn based upon the amendment and arguments of the applicant. Responses to the arguments are presented after the first rejection they are directed to.
In the event the determination of the status of the application as subject to AIA 35 U.S.C. 102 and 103 (or as subject to pre-AIA 35 U.S.C. 102 and 103) is incorrect, any correction of the statutory basis (i.e., changing from AIA to pre-AIA ) for the rejection will not be considered a new ground of rejection if the prior art relied upon, and the rationale supporting the rejection, would be the same under either status.
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 1,4,9-10,13-14,16-18 and 20 are rejected under 35 U.S.C. 103 as obvious over Yu et al. 20140205938, in view of Van Lare et al. WO 2020160851, Ogase et al. JP 2012104751, Ishiyama JP 2002299227 and Kirchauer et al. 6479195.
Yu et al. 20130157177 teaches an EUV mask in figure 4, which includes an antireflection pattern having a series of trenches (410) . The difference in the traveling length (e.g. the depth of the ARC trench (410) of reflected light rays 250 and 450 results a phase difference when they interfere with each other [0022-0023]. The etching process may include dry etching, wet etching, and/or other etching methods. The absorption layer 140 etching process may not only be chosen to achieve a high resolution for EUV masks but also to have a tight and uniform distribution of the critical dimension (CD) over the EUV mask 400 [0024]. Figure 5 shows these extending into the mask border area (510) and within the main pattern area (520)
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The ARC trenches have a depth to produce destructive interference among reflected light rays from the absorptive regions, and display in various pattern in the absorptive regions in different mask areas [0005]. The depth of the ARC trench 410 is tuned to have a dimension such that a destructive interference is produced between the reflected light ray 250 and 450. With the chosen depth of the ARC trenches 410, reflected light rays 250 and 450 will be opposite in phase with respect to each other and cancel each other out by destructive interference. Hence, undesirable reflections from absorption layer 140 in the absorptive region 210 are reduced. Due to the periodic nature of destructive interference, various depths of the ARC trenches 410 can be chosen. The depths of the ARC trenches 410 can be chosen differently in different absorptive regions 210 of mask areas of the EUV mask 400. In the depicted embodiment, the depth of the ARC trenches 410 is about 40 nm formed in the LR-TaBN absorption layer 140. The ARC trenches 410 can be formed with various trench profiles, such as vertical, non-vertical, flat-bottom trench and non-flat-bottom trench. In the depicted embodiment, the ARC trenches 410 are formed in a vertical trench profile with a flat bottom. The ARC trenches 410 can be displayed in various ARC-patterns, such as a dense line pattern, dense hole pattern or other suitable patterns. Different ARC patterns (by ARC trenches 410) can be used in the absorptive regions 210 of different mask areas, such as in a mask border area 510 and in a mask main pattern area 520 (as shown in FIG. 5). The ARC trenches 410 and the reflective regions 220 can be formed together by a single patterning process or be formed separately by a multiple patterning processes. In the depicted embodiment, the ARC trenches 410 is formed with the reflective regions 220 together by a single patterning process [0022-0023]. An absorption layer 140 is formed on the capping layer 130. The absorption layer 140 preferably absorbs radiation in the EUV wavelength ranges projected onto the patterned EUV mask. The absorption layer 140 may include chromium, chromium oxide, titanium nitride, tantalum nitride, tantalum, titanium, or aluminum-copper. The absorption layer 140 may be formed of multiple layers. For example, the absorption layer 140 is formed by a dual-layer of chromium and tantalum nitride. In the depicted embodiment, the absorption layer 140 includes low reflectivity tantalum boron nitride (LR-TaBN). In a subsequent etching process, LR-TaBN shows a more anisotropically and a faster etch than chromium. LR-TaBN also shows adequate overetch tolerance, a controllable etch profile, and a negligible etch bias. The absorption layer 140 may be any suitable thickness for a given material to achieve an adequate absorption [0016].
Van Lare et al. WO 2020160851 teaches attenuating phase shift EUV masks (abstract) As can be seen in Figures 12a and 12b, the second component 54 covers the entire first component 52 (i.e. covered portions 52b of the first component 52) except for an uncovered portion 52a of the first component 52 and further uncovered portions 52c of the first component 52 where the channels 55 are located. These further uncovered portions 52c do not result in corresponding features being formed in the substrate W (as the uncovered portion 52a does) as will become apparent. [000106] In this embodiment, the widths of the sections 54a of the second component 54 and the widths of the channel 55, and thus the widths of the further uncovered portions 52c are substantially the same. However, in other embodiments, the widths may be different, both between different sections 54a and/or between the sections 54a and the channels 55 [000105].
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The second component 54 may be considered to form thin horizontal lines on the patterning device 50 with the channels 55 being between the lines. This pattern of repeating horizontal lines may be the most preferable solution for manufacturing the mask. In other embodiments, the second component 54 may have a different pattern. For example, a matrix of small regular holes (i.e. spaces) that extend in both the X and Y directions may be used. More generally, the patterning device has the arrangement of the second component such that there is a repeating pattern of sections of the second component across the patterning device (e.g. in the X direction). The sections of the second component are separated by spaces (c.f. channels) to uncover the further uncovered portions of the first component. The first component 52 and the second component 54 may be made the same as in the attenuated phase shift patterning device MA of Figure 2, that is the first component 52 is a multilayer and the second component 54 may comprise Ru. In other embodiments, the second component 54 may comprise, for example, Rh, Tc, Mo or Re. The second component 54 may comprise an alloy of Ru, Rh, Tc, Mo or Re. These materials may have a refractive index with a relatively low real part n (e.g. less than 0.95) and a relatively low imaginary part k (e.g. less than 0.04). Thus, the second component 54 provides the phase shift and thereby enhances the contrast in the same way as described above. That is, the benefits of the attenuated phase shift patterning device MA of Figure 2 are also achieved using the attenuated phase shift patterning device 50. The arrangement of the second component 54 has a sub-resolution pitch. That is, the distance between the sections 54a of the second component 54 (i.e. the pitch) is below the resolution that is printed on the substrate W. This means that the further uncovered portions 52c of the first component 52 will not be printed on the substrate W. The further uncovered portions 52c of the first component 52 which are located below the channels 55 are sub resolution assist features (SRAF). In examples, the at resolution pitch may be 26nm or 16nm and so the line pitch may be less than 26nm or less than 16nm respectively. The critical dimension (CD) of the lines is about half of the pitch and so less than 13nm or less than 8nm [000108-000110]. With the attenuated phase shift patterning device 50 the features can be tweaked (pitch and mask bias) to get most of the radiation outside the 0th order. Therefore, the background radiation problem will be improved. The pitch is sub-resolution but, at the sub resolution pitch, it is possible to e.g. make the pitch even smaller or to tune the size (e.g. width) of the lines (sections 54a of the second component 54) in such a way that further increases the amount of radiation that is diffracted out of the zeroth order. Mask bias is the size of the lines (sections 54a of the second component 54). For example, a pitch of 20nm may be used. That can mean that there are alternating lines of 10 nm and channels of 10 nm. However, it could also mean that there are alternating lines of 12nm and channels of 8nm. Both these examples have a pitch of 20 but in the first case there is bias of 0 and in the second case there is a bias of +2. The attenuated phase shift patterning device 50 provides an enhanced NILS and improved dose whilst suppressing background for isolated patterns. This, in turn will improve yield and throughput of the lithographic apparatus LA [000114]. The second component may comprise one or more of Ru, Pt, Ta or Co. In other embodiments, the second component may comprise an alloy comprising one or more of Ru, Pt, Ta or Co. The materials may be compatible to be used within the lithographic apparatus LA, e.g. silver (Ag) and palladium (Pd) may not be suitable for use in the lithographic apparatus LA. The phase shift produced by the patterning device MA may be 1.2p to provide the desired performance, i.e. highest NILS and low mask 3D effects [000128]. The attenuated phase shift patterning device MA comprises a first component 22 for reflecting radiation and a second component 24 for reflecting radiation with a different phase with respect to the radiation reflected from the first component. The first component 22 comprises a standard multilayer mirror, e.g. alternating layers of molybdenum and silicon. The layers of the multilayer are not shown in Figure 2a for simplicity. It will be appreciated that in other embodiments, the first component may have different numbers of layers and/or may comprise different materials [00049]. In this embodiment, the second component 24 comprises the material Ruthenium (Ru) with a thickness t (shown as a double arrow in Figures 2a and 2b) of 35nm. The material Ru of the second component 24 may be considered to have replaced an absorbing material, e.g. a TaBN absorber, in a standard patterning device to form the attenuated phase shift patterning device MA. As will be appreciated, in other embodiments, different materials may be used in place of Ru, as detailed later [00056]. The third component 36 is for absorbing radiation. The third component 36 comprises an alloy of Ta with a Ru capping layer. This Ru capping layer is in addition to the second component 34 which may also be Ru. The Ta alloy has a refractive index with a relatively high imaginary part (k). In other embodiments, the material may comprise Ta without another element present. In other embodiments, the third component may comprise a different material, such as Ag, Pt, Pd, Au, Ir, Os, Re, In, Co, Cd, Pb, Fe, Hg, TI, Cu, Zn, I, Te, Ga, Cr, W, Hf or an alloy comprising one or more of these materials, or a TaBN absorber. More generally, the third component 36 may comprise a material having a refractive index with a larger imaginary part (k) than the material of the second component 34, i.e. in this embodiment Ru. In some embodiments, the third component 36 may have a material having a refractive index with an imaginary part (k) in the range 0.031 (i.e. k of TaBN) to 0.08 (i.e. k of Ag). As an example, the imaginary part (k) may be 0.065 (i.e. k of Co) [00086].
Ogase et al. JP 2012104751 (machine translation attached) describes an EUV mask including a reflective Mo/Si multilayer, a Ru capping layer and a TaN absorber layer which is initially formed with a thickness of 70 nm, it was then patterned using a resist and then the resist was removed the absorber was globally/uniformly etched to a target thickness of 65 ± 1 nm [0050-0055]. The thickness adjustment is to be 1 nm precision [0041].
Ishiyama JP 2002299227 (machine translation attached) teaches a reflective mask formed on a substrate including a Mo/Si reflective multilayer, a 30 nm Cr, which is coated with a resist. The resist is then patterned and used to pattern the absorber. The resist is then removed, another resist was coated and the surface of the absorber and resist were etched for a short period of time. The roughness of the surface was 1.9 nm rms (see figure 2a-e and 3a-i) [0025-0034]. increased surface roughness of the absorber can improve contrast and the absorber thickness can be smaller. When the absorber has an RMS roughness of 1 nm, the EUV light is scattered by 60% (more) than with a perfectly smooth surface. When the absorber has a 0.5nm RMS roughness, the contrast is 70. When the surface roughness of 0.6 nm RMS, the contrast is 100. When the surface roughness is 1 nm RMS., the contrast is 200. When the surface roughness is 2 nm RMS, a contrast of 150 can be achieved with only a thickness of 20 nm [0048-0051] The use of a Ta-Au absorber with a surface roughness of 1.2 nm RMS is disclosed [0061]. The use of a Ni absorber with a surface roughness of 2.0 nm RMS is disclosed [0072].
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Kirchauer et al. 6479195 teaches with respect to figure 3, the upper surface of the absorber having a roughness of 2-15 nm rms (col 4/lines 16-25)
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This is formed by roughening the upper surface of an absorber by etching using a dry or wet etch. And then patterning the absorber (an underlying buffer layer if desired.)(col 7/lines 1-28).
Yu et al. 20130157177 does not exemplify the use of an absorber layer with at least 5% reflectivity, an absorber with a reflective index of 0.95 or less and an absorption coefficient of 0.04 or less, the sub-resolution recesses/patterns having a dimensions/widths of 10-50 nm or the sub-resolution recesses/patterns having a variations in the depths of 1-10 nm.
With respect to claims 9-10,13-14,16-18 and 20, it would have been obvious to modify the embodiment of figure 5 of Yu et al. 20130157177 which shows grooves formed by etching which are 40-90% of the thickness of the absorber layer by replacing the absorber layer with an attenuating phases shift layer such as taught by Van Lare et al. WO 2020160851 as replacing the absorber layers of the prior art at [00056, 00086] with a reasonable expectation of forming a useful EUV attenuating phase shift mask based upon the disclosure of the phase difference between the reflected light 250 and 450 in figure 4 at [0022-0023] and the examiner holds that the grooves inherently have variations in depth corresponding to between 1 and 10 nm, based upon the roughness generated by etching absorber layers evidenced by the teachings of Ogase et al. JP 2012104751, Ishiyama JP 2002299227 and Kirchauer et al. 6479195.
Alternatively, with respect to claims 9-10,13-14,16-18 and 20, it would have been obvious to modify the embodiment of figure 5 of Yu et al. 20130157177 by replacing the absorber layer with an attenuating phases shift layer such as taught by Van Lare et al. WO 2020160851 as replacing the absorber layers of the prior art at [00056, 00086] and forming the grooves by etching the attenuating phase shift layer to a depth which is within the range of 40-90% of the thickness of the attenuating phase shift layer where the reflected light 250 and 450 in figure 4 destructively interfere with a reasonable expectation of forming a useful EUV attenuating phase shift mask, noting that the specific thickness of the remaining absorber/attenuating layer is not critical at [0022-0023] and the examiner holds that the grooves inherently have variations in depth corresponding to between 1 and 10 nm, based upon the roughness generated by etching absorber layers evidenced by the teachings of Ogase et al. JP 2012104751, Ishiyama JP 2002299227 and Kirchauer et al. 6479195.
Alternatively, with respect to claims 1,4,9-10,13-14,16-18 and 20, it would have been obvious to modify the embodiment of figure 5 of Yu et al. 20130157177 by replacing the absorber layer with an attenuating phases shift layer such as taught by Van Lare et al. WO 2020160851 as replacing the absorber layers of the prior art at [00056, 00086] and forming the grooves by etching the attenuating phase shift layer to a depth which is within the range of 40-90% of the thickness of the attenuating phase shift layer where the reflected light 250 and 450 in figure 4 destructively interfere with a reasonable expectation of forming a useful EUV attenuating phase shift mask, noting that the specific thickness of the remaining absorber/attenuating layer is not critical at [0022-0023] and to form the grooves with a line/space of 8,10 or 13 nm based upon the disclosed pitches of 16 [000108-000110], 20 [000114] or 26 [000108-000110] nm, so the line widths are half this or 8, 10 or 13 in Van Lare et al. WO 2020160851 and the examiner holds that the grooves inherently have variations in depth corresponding to between 1 and 10 nm, based upon the roughness generated by etching absorber layers evidenced by the teachings of Ogase et al. JP 2012104751, Ishiyama JP 2002299227 and Kirchauer et al. 6479195.
The topmost layer of the reflective multilayer (130) in Yu et al. in a capping layer.
The applicant argues that the prior art applied does not teach the sub-resolution assist features or background suppression features being formed to depths of 40-90% of the thickness of the absorber layer. Yu et al. 20130157177 provides a teaching of this limitation both in the illustration and the associated text which describes the use of any thickness where the light reflected through the entire thickness of the absorber (250) and that reflected but passing through only the thinner absorber (450) at the bottom of grooves (410).
In the response of 1/15/2026, the applicant argues that the combination of the references does not teach the recesses with depths of 40-90% of the thickness of the absorber layer and the variation in the depths being 1-10 nm. As discussed previously, figures 4 and 5 of Yu et al. illustrate recesses which are 40-90% of the thickness of the absorber. These recesses/grooves are formed by etching the full thickness absorber and secondary references Ogase et al. JP 2012104751, Ishiyama JP 2002299227 and Kirchauer et al. 6479195 evidence that grooves formed by etching inherently have variations in depth (roughness) corresponding to between 1 and 10 nm. The rejection ass modified above stands
The applicant also argues that the (EUV) binary (absorber) masks and phase shift masks have different structures and operate in a different manner, so the combination of Yu et al. and Van Lare et al. WO 2020160851 would not have been obvious to one of ordinary skill in the art. First, Yu et al. is not a purely binary absorber mask as there are three levels/thicknesses (no absorber), partial absorber thickness and full absorber thickness). This argument ignores that teaching in Van Lare et al. WO 2020160851 specifically describing replacing the absorber layers of the prior art at [00056, 00086] with the attenuated phase shift layer. This arguments is not persuasive.
In the response of 5/19/2026, the applicant argues that the surface roughness is a measure of roughness of the surface, not the difference in the depth. This position does not account for the fact that small (~1-3 nm) differences in the height of the absorber when formed are compounded by the variations in the etching process. It does not stand to reason that when discussing variation in the depth of the features, the variation in the initial height is not relevant. The applicant argues that the examiner has used references which form different photomasks. Yu et al. 20140205938, Van Lare et al. WO 2020160851, Ogase et al. JP 2012104751, Ishiyama JP 2002299227 and Kirchauer et al. 6479195 are all forming reflective EUV photomasks. While some of the references are not related to reflective EUV photomasks, they are analogous, disclosing known patterns in the photomask art.
In response to applicant's argument that the examiner's conclusion of obviousness is based upon improper hindsight reasoning, it must be recognized that any judgment on obviousness is in a sense necessarily a reconstruction based upon hindsight reasoning. But so long as it takes into account only knowledge which was within the level of ordinary skill at the time the claimed invention was made, and does not include knowledge gleaned only from the applicant's disclosure, such a reconstruction is proper. See In re McLaughlin, 443 F.2d 1392, 170 USPQ 209 (CCPA 1971). Some of the references applied describe the surface roughness or variation in the absorber layer. These teachings are relevant to the question of variation in the depth of the features. It does not stand to reason that when discussing variation in the depth of the features, the variation in the initial height is not relevant. The position of the examiner is that the lower range of the 1-10 nm variation seems to yield viable photomasks. The uniformity of the depth might be more critical for phase shifting masks, but the applicant has not addressed this and the specific changes in the phase associated with the 1-10 nm thickness differences. The rejection stands
Claims 1-4,9-10,12-14 and 17-20 are rejected under 35 U.S.C. 103 as obvious over Yu et al. 20130157177, in view of Van Lare et al. WO 2020160851, Ogase et al. JP 2012104751, Ishiyama JP 2002299227 and Kirchauer et al. 6479195, further in view of Liu et al. 20200004137, Hsu et al. 20200041891 and Lu et al. 20220066312.
Liu et al. 20200004137 teaches when the optical lithography tool is an EUV scanner with 13.5 nm range wavelength, the width Ws of the sub-resolution pattern SRP is in a range from about 20 nm to about 80 nm in some embodiments, and is in a range from about 30 nm to about 60 nm in other embodiments [0037].
Hsu et al. 20200041891 teaches the anticipated width of a clear SRAF for a patterning device may have a dimension that is so small (e.g., 30 nm or less) that, e.g., it is smaller than the optical resolution of a lithography process used to manufacture the patterning device or it is smaller than can be reliably produced (e.g., due to a high aspect ratio of being higher than wide). So, even though a clear SRAF could be able to accommodate the shorter wavelengths of radiation, including EUV radiation used in some embodiments of lithography methods, and/or work with increasing numerical aperture, the dimension of a SRAF could be so narrow that it cannot be currently or reliably manufactured using a lithography process [0074]. an attenuated SRAF has a larger width than a comparable clear SRAF with a comparable performance for a particular patterning process using a particular combination of radiation wavelength and numerical aperture. In an embodiment, the attenuated SRAF has a comparable performance for a clear SRAF having a width of less than or equal to 30 nm, less than or equal to 25 nm, less than or equal to 15 nm, less than or equal to 10 nm, less than or equal 5 nm, or less than or equal to 3 nm. In an embodiment, the attenuated SRAF does not print with radiation of 14 nm or less wavelength and a numerical aperture greater than 0.30 and has a width greater than or equal 15 nm, greater than or equal to 20 nm, greater than or equal to 25 or greater than or equal to 30 nm [0079]
Lu et al. 20220066312 illustrates in figure 8, an EUV mask including a printing features (120/1200) surrounded a pacing (S) and venting features in region (180). The venting features can be various repeating units, such as those illustrated in figures 7A-C. The spacing can be 1 to 1.5 microns [0026-0027]. The venting features can be either printable or sub-resolution. The sub-resolution features can have lengths of 100nm to 2 microns and widths of about 2 to 12 nm and may be at a pitch of 20-200 nm and to not form images during the exposure. [0028]. The mask 100 may have a construction illustrated in FIG. 2. In some embodiments, the mask 100 includes a substrate 102 with a reflector (or a reflective layer) such as a multi-layer mirror (MLM) 104 disposed on the substrate 102. In turn, an absorptive layer 108 is disposed on the MLM 104. The composition of the substrate 102, the MLM 104, and the absorptive layer 108 are described in detail below. However, at a high level, regions of the mask 100 where the absorptive layer 108 is present absorb incident radiation, whereas regions of the mask 100 where the absorptive layer 108 is not present reflect incident radiation towards a target [0020].
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It would have been obvious to one skilled in the art to modify the masks anticipated or rendered obvious by the combination of Yu et al. 20130157177 , Van Lare et al. WO 2020160851, Ogase et al. JP 2012104751, Ishiyama JP 2002299227 and Kirchauer et al. 6479195 discussed above by using other widths for the sub-resolution vent features within the 10-50 nm range based upon the disclosure of 20-80 nm EUV sub-resolution features in Liu et al. 20200004137 at [0037], 30 nm or less in Hsu et al. 2020004189 at [0079] and 2-12 nm disclosed at [0028] of Lu et al. 20220066312.
Further, it would have been obvious to one skilled in the art to arrange the sub-resolution features in the mask rendered obvious by the combination of Yu et al. 20130157177 , Van Lare et al. WO 2020160851, Ogase et al. JP 2012104751, Ishiyama JP 2002299227, Kirchauer et al. 6479195, Liu et al. 20200004137, Hsu et al. 20200041891 and Lu et al. 20220066312 at a pitch of 140-160nm with a reasonable expectation of forming useful EUV mask based upon the pitches of 20-200 nm disclosed at [0028] or Lu et al. 20220066312
Claims 1-7,9-14 and 17-20 are rejected under 35 U.S.C. 103 as obvious over Yu et al. 20130157177, in view of Van Lare et al. WO 2020160851, Yu et al. 20130157177 , Van Lare et al. WO 2020160851, Ogase et al. JP 2012104751, Ishiyama JP 2002299227, Kirchauer et al. 6479195Liu et al. 20200004137, Hsu et al. 20200041891 and Lu et al. 20220066312, further in view of Hsu et al., 200501026648 and/or Aburada et al. 20130063707.
Hsu et al., 200501026648 teaches mask patterns with sub-resolution features including lines to be printed surrounded by sub-resolution lines, as in figures 5A and 18B
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while the SGB lines illustrated in FIGS. 10a and 10b are discontinuous, it is also possible to have continuous lines or other shapes, for example, but not limited to square, circular [0093] In the present document, the terms "radiation" and "beam" are used to encompass all types of electromagnetic radiation, including ultraviolet radiation (e.g. with a wavelength of 365, 248, 193, 157 or 126 nm) and EUV (extreme ultra-violet radiation, e.g. having a wavelength in the range 5-20 nm) [0026].
Aburada et al. 20130063707 teaches EUV masks including the embodiment of 5A-5C,where, the dummy layout pattern PD may be formed arounds the layout pattern (see figures 5A and 5B). This reduces flare variation during the exposure. The dummy may print onto the (resist coated) wafer [0038]
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It would have been obvious to one skilled in the art to modify the masks rendered obvious by the combination of Yu et al. 20130157177, Van Lare et al. WO 2020160851, Yu et al. 20130157177 , Van Lare et al. WO 2020160851, Ogase et al. JP 2012104751, Ishiyama JP 2002299227, Kirchauer et al. 6479195, Liu et al. 20200004137, Hsu et al. 20200041891 and Lu et al. 20220066312 discussed above by using known circuit patterns such as those including period groups of lines where the lines of the circuit pattern are oriented orthogonally to the lines of the sub-resolution pattern as taught in figures 5A and 18B of Hsu et al., 200501026648 with a reasonable expectation of forming a useful EUV photomask.
Alternatively, it would have been obvious to one skilled in the art to modify the masks rendered obvious by the combination of Yu et al. 20130157177, Van Lare et al. WO 2020160851, Yu et al. 20130157177 , Van Lare et al. WO 2020160851, Ogase et al. JP 2012104751, Ishiyama JP 2002299227, Kirchauer et al. 6479195, Liu et al. 20200004137, Hsu et al. 20200041891 and Lu et al. 20220066312 discussed above by using known circuit patterns such as those including period groups of lines where the lines of the circuit pattern are oriented parallel to the lines of the sub-resolution pattern and the sub-resolution patterns conform closely to the printable lines in the circuit pattern as taught in figures 5A-C of Aburada et al. 20130063707 with a reasonable expectation of forming a useful EUV photomask.
Alternatively It would have been obvious to one skilled in the art to modify the masks rendered obvious by the combination of Yu et al. 20130157177, Van Lare et al. WO 2020160851, Yu et al. 20130157177 , Van Lare et al. WO 2020160851, Ogase et al. JP 2012104751, Ishiyama JP 2002299227 Kirchauer et al. 6479195, Liu et al. 20200004137, Hsu et al. 20200041891 and Lu et al. 20220066312 discussed above by using known circuit patterns such as those including period groups of dummy lines where the lines of the circuit pattern are oriented orthogonally to the lines of the sub-resolution/dummy pattern as taught in figures 5A and 18B of Hsu et al., 200501026648 and the sub-resolution patterns conform closely to the printable lines in the circuit pattern as taught in figures 5A-C of Aburada et al. 20130063707 with a reasonable expectation of forming a useful EUV photomask, noting that Lu et al. 20220066312 teaches the venting features can be printable or sub-resolution.
Further, it would have been obvious to modify the masks rendered obvious by the combination of references as discussed above by using square or circular sub-resolution features based upon the disclosure at [0093] of Hsu et al., 200501026648. As the sub-resolution feature do not print out, their shape and/or orientation do not confer patentability.
Claims 1-4,9-15 and 17-20 are rejected under 35 U.S.C. 103 as obvious over Yu et al. 20130157177 , in view of Van Lare et al. WO 2020160851, Ogase et al. JP 2012104751, Ishiyama JP 2002299227, Kirchauer et al. 6479195, Liu et al. 20200004137, Hsu et al. 20200041891 and Lu et al. 20220066312, further in view of Lin et al. 20150370942
Lin et al. 20150370942 teaches the pattern of the non-printable dummy features 172 may be a matrix of squares (as illustrated in FIG. 9), or rectangles (bars, (as illustrated in FIG. 10), or irregular dummy array (as illustrated in FIG. 11) [0038]. In FIG. 11, the non-printable dummy features 172 may be configured to an irregular dummy array. Here the non-printable dummy features 172 are chosen such that total dummy area/block region area=R. The parameter R is the target block dummy density ratio. Figure 7A,9 and 10 illustrates a square periodic arrays (2D grating), Figure 8a illustrates a linear grating. 11 is an irregular (non-periodic) array of squares.
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In addition to the basis above, it would have been obvious to one skilled in the art to modify the masks rendered obvious by the combination of Yu et al. 20130157177, Van Lare et al. WO 2020160851, Yu et al. 20130157177 , Van Lare et al. WO 2020160851, Ogase et al. JP 2012104751, Ishiyama JP 2002299227, Kirchauer et al. 6479195, Liu et al. 20200004137, Hsu et al. 20200041891 and Lu et al. 20220066312 discussed above by using irregular patterns based upon the use of these arrangements and shapes within the art as subresolution patterns as evidenced by Lin et al. 20150370942
Claims 1,4,9-10,13-14,17-18 and 20-23 are rejected under 35 U.S.C. 103 as obvious over Yu et al. 20140205938, in view of Van Lare et al. WO 2020160851, Ogase et al. JP 2012104751, Ishiyama JP 2002299227 and Kirchauer et al. 6479195, further in view of Burhardt et al. 20140199615, Shishido et al. 20110269060 or Cai et al. 20160062231.
Burhardt et al. 20140199615 teaches the use of SRAF cross patterns in figure 9 and polygons having recesses and protrusions in figure 10 [0068-0070]
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Cai et al. 20160062231 describes with respect to figure 11A, SRAFs (130) with zig-zag shapes
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Shishido et al. 20110269060 teaches with respect to figures 2,3 and 8, patterns with sub-resolution zigzag features [0057,0072,0141]
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In addition to the basis above, the examiner holds that it would have been obvious to one skilled in the art to modify the masks rendered obvious by the combination of Yu et al. 20140205938,Van Lare et al. WO 2020160851, Ogase et al. JP 2012104751, Ishiyama JP 2002299227 and Kirchauer et al. 6479195 by forming the sub-resolution patterns with shapes of crosses as in figure 9 of Burhardt et al. 20140199615, polygonal patterns having concave recesses and convex protrusions as in Burhardt et al. 20140199615, Shishido et al. 20110269060 or Cai et al. 20160062231, zig-zag patterns as taught by Shishido et al. 20110269060 or Cai et al. 20160062231 with a reasonable expectation of forming a useful photomask, noting that as these patterns are sub-resolution, their exact/specific shape does not matter as they block light, but do not print out in the resist.
Claims 1-7,9-14 and 17-23 are rejected under 35 U.S.C. 103 as obvious over Yu et al. 20130157177, in view of Van Lare et al. WO 2020160851, Yu et al. 20130157177 , Van Lare et al. WO 2020160851, Ogase et al. JP 2012104751, Ishiyama JP 2002299227, Kirchauer et al. 6479195 and Liu et al. 20200004137, Hsu et al. 20200041891 and Lu et al. 20220066312, further in view of Burhardt et al. 20140199615, Shishido et al. 20110269060 or Cai et al. 20160062231.
In addition to the basis above, the examiner holds that it would have been obvious to one skilled in the art to modify the masks rendered obvious by the combination of Yu et al. 20140205938,Van Lare et al. WO 2020160851, Ogase et al. JP 2012104751, Ishiyama JP 2002299227, Kirchauer et al. 6479195 and Liu et al. 20200004137, Hsu et al. 20200041891 and Lu et al. 20220066312 by forming the sub-resolution patterns with shapes of crosses as in figure 9 of Burhardt et al. 20140199615, polygonal patterns having concave recesses and convex protrusions as in Burhardt et al. 20140199615, Shishido et al. 20110269060 or Cai et al. 20160062231, zig-zag patterns as taught by Shishido et al. 20110269060 or Cai et al. 20160062231 with a reasonable expectation of forming a useful photomask, noting that as these patterns are sub-resolution, their exact/specific shape does not matter as they block light, but do not print out in the resist.
The prior art made of record and not relied upon is considered pertinent to applicant's disclosure.
Melvin et al. 20200089101 teaches that Some embodiments allow different sized SRAFs with different amounts of absorber variation. Specifically, in the bright-field case the absorber thickness can be varied, and in the dark-field case the amount of absorber that is added or left in the trench can be varied. In some embodiments, different SRAFs on the same reticle can have different widths and/or different thickness/absorber additions. In some embodiments, the same SRAF on a single pattern can have variations in its SRAF width and/or absorber thickness [0050]. Some embodiments vary the height or amount of absorber material of the SRAF shape and the width of the SRAF shape to maximize the impact of the SRAF shape (e.g., maximize the improvement in contrast of main feature shapes if the SRAF shape is being used for that purpose) without causing the SRAF shape to print. In general, the lesser the amount of absorber material associated with the SRAF shape, the wider the SRAF shape can be without printing [0057]
Hayashi et al. WO 2012114980 (machine translation attached) describes the variation int hew thickness of the absorber layer as being within ±2% [0037]
Cho et al. 20230176470 teaches with respect to 12c, curvilinear subresolution feature [0008]
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Broeke et al. 20060075377 teaches assist features formed of polygons arranged in the curved pattern (figure 2c and 2d).
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Liebmann et al. 20040170905 teaches “L” shaped assist features (A3’,A4’) in figure 3.
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Moon et al. WO 2020187578 teaches sub-resolution attest features can be a pixelated, binary Manhattan (an arrangement of connected rectangular patterns) , binary curvilinear, or continuous tone image [0078]
Kai et al. JP 2011186312 (machine translation attached) teaches with respect to figure 7, a n the photomask 42Z, the SRAF portion 212D is configured with a pattern layout having a shape different from that of the periodic pattern 21A. Specifically, the SRAF unit 212D is configured such that the light shielding unit 132D of the SRAF unit 212D is configured by a grid pattern, and the gap portion (island region) of the grid pattern is the transmission unit 122D. For example, the light shielding part 132D is arranged in both the direction in which the light shielding part 13A is arranged (horizontal direction in FIG. 7) and the direction perpendicular to the direction (vertical direction in FIG. 7) (longitudinal direction of the light shielding part 13A). It has a lattice shape. Further, in the SRAF unit 212D, the region of the transmission unit 122D is determined so that the zero-order light L0x and the first-order light L1x irradiated onto the wafer 6X via the SRAF unit 212D are equal. This realizes the SRAF unit 212D to be SRAF and balances the diffracted light intensities of the zero-order light L0x and the first-order light L1x of the SRAF unit 212D [0056]
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Yan et al. 20060222961 teaches that the phase difference between the principal light rays oscillates with half the wavelength of the incident light. Constructive and destructive interference may occur for absorber height 350 differing by only a quarter of a wavelength or about 3 nm. A variation in absorber height 350 of 3 nm may cause linewidth on the wafer to vary by about 4 nm [0022].
Terasawa et al. JP 2012052870 (machine translation attached) teaches that when a height abnormality of about 2 to 3 nm occurs in the mask blank, the height abnormality gives a large phase change to the reflected light from the surface on which the absorber pattern is formed. As a result, a defect is generated in the pattern transferred onto the main surface of the wafer. Therefore, before depositing the absorber pattern on the mask blank, it is necessary to detect an abnormal height (hereinafter referred to as a phase defect) generated in the mask blank [0005]
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 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, Ching-Yu (Coris) Fung can be reached at 571-270-5713. The fax phone number for the organization where this application or proceeding is assigned is 571-273-8300.
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MARTIN J. ANGEBRANNDT
Primary Examiner
Art Unit 1737
/MARTIN J ANGEBRANNDT/Primary Examiner, Art Unit 1737 June 11, 2026
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