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 .
Response to Amendment
Applicant’s Amendment filed 08/28/2025 has been entered and is being considered. Claims 1, 5, 7, 12, 15, and 22 are amended. Claims 11, 13, 14, and 23 are canceled. Claims 27-30 are newly added. No new matter has been added with these amendments.
Response to Arguments
Applicant’s arguments, filed 08/28/2025, with respect to the 35 USC 112b rejections have been overcome with the amendment made to the repeating unit structure for polyacrylic acid. This rejection has been withdrawn.
Applicant’s arguments, filed 08/28/2025, with respect to the 35 USC 103 rejections have been fully considered but they are not persuasive. After further consideration of the prior art relied upon, Sung further teaches that a photoresist composition may further comprise a preferred optional additive such as an added base (paragraph [0050]) and the newly added embodiments of Claims 27-30 as the crosslinkable components a5 ([0173-0176]). Additionally, Chen ‘431 (US 2013/0122421), which was relied upon in the rejection of Claim 13 of the prior office action teaches the claimed quencher. See the detailed action below.
Claim Rejections - 35 USC § 103
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 35 U.S.C. 103 which forms the basis for all obviousness rejections set forth in this Office action:
A patent for a claimed invention may not be obtained, notwithstanding that the claimed invention is not identically disclosed as set forth in section 102, if the differences between the claimed invention and the prior art are such that the claimed invention as a whole would have been obvious before the effective filing date of the claimed invention to a person having ordinary skill in the art to which the claimed invention pertains. Patentability shall not be negated by the manner in which the invention was made.
The text of those sections of Title 35, U.S. Code not included in this action can be found in a prior Office action.
The factual inquiries for establishing a background for determining obviousness under 35 U.S.C. 103 are summarized as follows:
1. Determining the scope and contents of the prior art.
2. Ascertaining the differences between the prior art and the claims at issue.
3. Resolving the level of ordinary skill in the pertinent art.
4. Considering objective evidence present in the application indicating obviousness or nonobviousness.
This application currently names joint inventors. In considering patentability of the claims the examiner presumes that the subject matter of the various claims was commonly owned as of the effective filing date of the claimed invention(s) absent any evidence to the contrary. Applicant is advised of the obligation under 37 CFR 1.56 to point out the inventor and effective filing dates of each claim that was not commonly owned as of the effective filing date of the later invention in order for the examiner to consider the applicability of 35 U.S.C. 102(b)(2)(C) for any potential 35 U.S.C. 102(a)(2) prior art against the later invention.
Claims 1, 2, 5-7, 9, 12, 15-18, 22, 24-30 are rejected under 35 U.S.C. 103 as being unpatentable over Chang (US 2007/0254244) in view of Takahashi (US 2006/0183218), Sung (US 20180031975) and Chen ‘431 (US 2013/0122421).
Regarding Claims 1, 2, 5-7, 15-18, and 22, Chang teaches in Fig. 3A-E a method of making a resist structure utilizing a first photoresist and a second photoresist layer, wherein both photoresist layers are negative photoresists (paragraph [0032]). The second photoresist layer is crosslinked at the surface of the first photoresist layer due to acid diffusion from the residual acid remaining in the first photoresist layer into the second photoresist layer (paragraph [0032-0035]). The composition of the second photoresist preferably comprises a water-soluble resin capable of undergoing crosslinking in the presence of an acid, such as poly(acrylic acid) among select others (paragraph [0041-0042]). If the resin alone does not undergo a crosslinking reaction, a water-soluble crosslinking agent is needed such as urea group crosslinking agents such as urea, alkoxymethylene ureas, N-alkoxymethylene ureas, ethyleneurea, ethylene urea carboxylates and the like, melamine group crosslinking agents such as melamine, melamine derivative including alkoxymethylenemelamine, and amino crosslinking agents such as benzoguanamine, glycoluril and the like (paragraph [0044]) (Claim 5, 6, 15, 29). Thus, the second resist may not be limited to amino crosslinking agents, and may include any of water-soluble crosslinking agents that generates crosslinking in the presence of acid (paragraph [0044]). Chang further teaches a liquid developer such as tetramethylammonium hydroxide may be used for development (paragraph [0039]) (Claim 2). The resist pattern is used as a mask followed by etching the underlying semiconductor substrate or base layer (paragraph [0060]) (Claim 7, 15). The crosslinking agent is interpreted as the claimed dissolution inhibitor.
The first photoresist layer is a negative photoresist patterned by exposure to radiation and the second photoresist layer is crosslinked using residual acid generated from the first photoresist layer.
It would have been obvious for one of ordinary skill in the art to have substituted the compositions of the first photoresist layer for the second photoresist layer. The first and second photoresist layers both comprise negative photoresists; as such, one of ordinary skill would expect the substitution of the first negative photoresist layer with the second negative photoresist layer to be patternable in the same way as disclosed by Chang without further modification. The modification would yield a patternable poly(acrylic acid) photoresist when exposed to radiation.
Chang is silent to the compositional details of the polymer being greater than 40 wt% of a total solid weight of the negative tone photoresist and exposing using EUV radiation at a power of 20 mJ to 30 mJ. Chang is silent to the polymer being between 40 wt% and 60 wt% of a total solid weight of the negative tone photoresist.
Regarding the polymer content being greater than 40 wt% or between 40 to 60 wt% of the solid content of the negative tone photoresist, Examiner brings in Takahashi to teach similar fine resist pattern forming material for providing a cured coated layer pattern comprising a water-soluble crosslinking agent and a water-soluble resin (abstract). The water soluble resin includes poly(acrylic acid) derivatives like poly(acrylic acid) and poly(methacrylic acid) (paragraph [0026]). The water soluble crosslinking agents comprise urea or melamine derivatives, and based on 100 parts of resin, 5 to 60 parts of water-soluble crosslinking agent may be used (paragraph [0027]). These ranges would constitute a weight percentage of polymer resin between 100/(100+5)*100=95 wt% to 100/(100+60)*100=62.5 wt% (Claims 1, 7). Furthermore, the weight percentage of the water-soluble crosslinker would be 5 wt% to 37.5 wt% (Claim 16-18, 22)
In the case where the claimed ranges "overlap or lie inside ranges disclosed by the prior art" a prima facie case of obviousness exists. [In re Wertheim, 541 F.2d 257, 191 USPQ 90 (CCPA 1976); In re Woodruff, 919 F.2d 1575, 16 USPQ2d 1934 (Fed. Cir. 1990)]. Similarly, a prima facie case of obviousness exists where the claimed ranges or amounts do not overlap with the prior art but are merely close. [Titanium Metals Corp. of America v. Banner, 778 F.2d 775, 783, 227 USPQ 773, 779 (Fed. Cir. 1985)]. See MPEP 2144.05.
It would have been obvious for one of ordinary skill in the art to have modified the composition of Chang with the parts of water-soluble polymer and crosslinker disclosed in Takahashi. Chang and Takahashi both disclose water-soluble polymers with water-soluble crosslinkers for resist compositions and are analogous art. One of ordinary skill would reasonably expect this modification to produce working negative photoresist compositions.
Regarding exposing using EUV radiation at a power of 20 mJ to 30 mJ, Examiner brings in Sung to teach forming a photolithographic pattern by negative tone development (paragraph [0054]). Sung discloses a method of patternwise irradiation using electron beam or EUV compositions (paragraph [0068]). The photoresist layer is exposed to radiation through a photomask, where the wavelength of the exposure includes EUV (paragraph [0061]). The exposure energy is 10 to 80 mJ/cm2 and is dependent on the compositions of the photoresist composition (paragraph [0061]).
It would have been obvious for one of ordinary skill in the art to have modified the exposure of Chang with EUV exposure between 10 to 80 mJ/cm2 as disclosed in Sung. Sung demonstrates general photolithographic methods that could be applied to negative photoresists. One of ordinary skill in the art would reasonably expect such as modification to result in an EUV patternable negative-tone composition.
Regarding the resist composition comprising a quencher, Takahashi and Chang are silent to the photoresist compositions further containing this additive.
However, Sung further teaches in photoresist compositions that a preferred optional additive is an added base and gives suitable linear and cyclic amides and derivatives thereof to be incorporated at 0.01 to 5 wt% based on total solids of the photoresist composition (paragraph [0050-0051]).
Furthermore, Chen ‘431 discloses photoresist compositions comprising an acid generator and a crosslinking agent (abstract). The photoresist composition may include further performance enhancing additives like a weak base quencher, which is used to scavenge trace acids while not having an excessive impact on the performance of the photoresist (paragraph [0024]).
Examiner notes that base additives, and in particular amines, are known and widely used in the art to neutralize acid in photoresist compositions. The language used by Applicant “the polymer creates a hydroxyl radical and an acid, the acid is neutralized by the basic quencher and the hydroxyl radical reacts with the dissolution inhibitor to form a cross-linked compound” is interpreted as the polymer forming an acid H+ and a COO- on the polymer to react with the dissolution inhibitor to form a cross-linked compound.
It would have been obvious for one of ordinary skill in the art to have modified Chang and Sung with a base quencher disclosed in Chen ‘431. Sung already notes that base additives are preferred optional additives to include in photoresist compositions. One of ordinary skill would have been motivated to make this modification to scavenge trace acids as suggested by Chen ‘431.
Regarding Claim 9, the discussion of Claim 7 is relied upon as above. Sung further teaches in Fig 1A a cross-section of substrate 100 with layer 102 that may be a hardmask or an antireflective layer, and that suitable antireflective materials are known in the art (paragraph [0057-0058]).
Regarding Claim 12, the discussion of Claim 11 is relied upon as above. Sung further discloses the patterning composition can include a surfactant such as polyethylene glycols and other polymeric compounds such as tri-block Pluronics comprising polyethylene glycol and polypropylene glycol (paragraph [0040]).
Takahashi further teaches nonionic surfactants may be added such as various polyoxyethylene polymers (paragraph [0029]). Takahashi further discloses solvents such as ethyl lactate and other water soluble organic solvents (paragraph [0028-0030]). The solvents are used to solubilize the base polymer and any additives like a surfactant (paragraph [0030]).
Regarding Claims 24-26, the discussion of Claim 15 is relied upon as above. Chang further discloses the water-soluble crosslinking compounds may comprise benzoguanamine, melamine, and glycouril (paragraph [0044]). Chang is silent to the number of reactive sites on these compounds, but the chemical structures of each water-soluble crosslinker demonstrate the following: benzoguanamine contains 2 reactive amine sites, melamine contains 3 reactive amine sites, and glycouril contains 4 reactive amine sites.
Regarding Claims 27-30, the discussion of Claim 7 is relied upon as above. Sung further discloses the chemically amplified negative composition comprises a component a5 which is acid-catalytically polymerizable or crosslinkable with itself and or with the other components (paragraph [0173]). Examples thereof include cyclic ethers such as epoxides, vinyl ethers and hydroxy-containing compounds (paragraph [0176]). Such examples of component a5 include polyglycidyl ethers (paragraph [0200]) and other epoxidized novolak components (paragraph [0211]) (Claim 28). The hydroxy-containing compoiunds may include polyester polyols and other hydroxy-functional vinyl and acrylic resins (paragraph [0217]) (Claim 27). Vinyl ethers such as aromatic, aliphatic, or cyclialiphatic vinyl ethers and also silicon vinyl ethers are suitable components for crosslinking (paragraph [0220]) (Claim 30). In addition, melamine resins are further preferred acid-curable resins for component a5 (paragraph [0225]) (Claim 29).
Claim 10 is rejected under 35 U.S.C. 103 as being unpatentable over Chang (US 2007/0254244) in view of Takahashi (US 2006/0183218) and Sung (US 2018/0031975) as applied to Claim 9 further in view of Chen (US 2018/0149971).
Regarding Claim 10, the discussion of Claim 9 is relied upon as above. Sung further teaches in Fig 1A a cross-section of substrate 100 with layer 102 that may be a hardmask or an antireflective layer, and that suitable antireflective materials are known in the art (paragraph [0057-0058]).
Sung is silent to the particular antireflective material as instantly claimed, but states that any suitable antireflective materials are known in the art.
However, Chen teaches method for lithography comprising forming a photoresist layer over substrate (Abstract). The substrate includes an underlayer such as an anti-reflection coating (ARC) layer such as a nitrogen-free anti-reflection coating (NFARC) layer including material(s) such as silicon oxide, silicon oxygen carbide, or plasma enhanced chemical vapor deposited silicon oxide (paragraph [0023]).
It would have been obvious for one of ordinary skill in the art to have modified the antireflective layer generally disclosed in Sung with the specific antireflective layers disclosed in Chen. The antireflective layers are used for the same purpose, such that one of ordinary skill in the art would reasonably expect the substitution of one for another would form a working antireflective layer.
Conclusion
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 KEVIN JAMES DRUMMEY whose telephone number is (703)756-5419. The examiner can normally be reached Monday - Friday 7:30am-5:00pm EST.
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/K.J.D./Examiner, Art Unit 1737
/MARK F. HUFF/Supervisory Patent Examiner, Art Unit 1737