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 .
Information Disclosure Statement
The information disclosure statement (IDS) submitted on 07/26/2024 are being considered by the examiner.
Claim Rejections - 35 USC § 112
The following is a quotation of 35 U.S.C. 112(b):
(b) CONCLUSION.—The specification shall conclude with one or more claims particularly pointing out and distinctly claiming the subject matter which the inventor or a joint inventor regards as the invention.
The following is a quotation of 35 U.S.C. 112 (pre-AIA ), second paragraph:
The specification shall conclude with one or more claims particularly pointing out and distinctly claiming the subject matter which the applicant regards as his invention.
Claim 4 recites the limitation "the conductor" in line 1. There is insufficient antecedent basis for this limitation in the claim as claim 4 depends on claim 2, and claim to on claim 1, neither of which claim “a conductor”. The claim appears to be a typographical error and should be dependent upon claim 3. For examination purposes, claim 4 will be examined as if dependent upon claim 3.
Claim Rejections - 35 USC § 102
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.
Claims 1-4 are rejected under 35 U.S.C. 102(a)(1) and 102(a)(2) as being anticipated by Givens et al. (US 2021/0301391 A1).
Regarding claim 1, Givens et al. teaches a method (FIG. 1) of forming a layer according to atomic layer deposition, the method comprising:
providing a substrate (FIG. 2A, combination of first and second surfaces 204 + 202) which comprises a first region (202) comprising a first material ([0082], dielectric) and having a first surface (second surface 202), and a second region (204) comprising a second material ([0082], metal) and having a second surface (first surface 204);
forming a first reaction inhibition layer (passivation layer 206) on the second surface using a reaction inhibitor selectively adsorbed on the second surface ([0083]);
selectively forming a first deposition layer (layer 208) on the first surface using a first precursor and a first reactant ([0084]), wherein the first reactant reacts with the first precursor to form an atomic layer ([0085], 212 + 210, comprising first layer 212), and does not react with the reaction inhibitor to form the atomic layer; and
converting the first reaction inhibition layer on the second surface into a second deposition layer (second layer 210) using a second reactant ([0085]) which reacts with the first reaction inhibition layer to form the atomic layer.
It is noted that the substrate may be first treated as disclosed in [0066]-[0068], and precursor and reactant chemistries is disclosed in [0069]-[0073]. Furthermore, deposition cycles may be repeated and specific chemistries and concentrations engineered with X:Y ratios as disclosed in [0077]-[0078].
Regarding claim 2, Givens et al. teaches the method of claim 1, wherein the first material comprises an insulator (0069]).
Regarding claim 3, Givens et al. teaches the method of claim 1, wherein the second material comprises a conductor ([0069]).
Regarding claim 4, Givens et al. teaches the method of .
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 5-10 and 12 are rejected under 35 U.S.C. 103 as being unpatentable over Givens et al. (US 20210301391 A1) in view of Chen et al. (US 20190185993 A1).
Regarding claim 5, Givens et al. teaches the method of claim 1.
While Givens et al. teaches the reaction inhibitor chemistry, Givens et al. does not explicitly teach wherein the reaction inhibitor comprises a metal complex comprising a central metal and an organic ligand.
Chen et al., however, teaches wherein the reaction inhibitor ([0084], ruthenium precursor) comprises a metal complex comprising a central metal (ruthenium (Ru)) and an organic ligand (ethylcyclopentadienyl group).
It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to have modified the method of Givens et al. to have used the metal complex as taught by Chen et al. as the reaction inhibitor. Metal complexes like Ru(EtCp)2 selectively adsorb on metal surfaces to block ALD growth, which improves selectivity of the deposition process.
Regarding claim 6, Givens et al. in view of Chen et al. teaches the method of claim 5.
Givens et al. teaches the reaction inhibitor chemistry, but does not explicitly teach wherein the central metal of the reaction inhibitor comprises copper (Cu), aluminum (AI), tungsten (W), cobalt (Co), silver (Ag), gold (Au), platinum (Pt), iridium (Ir), rhodium (Rh), or ruthenium (Ru).
Chen et al., however, teaches wherein the central metal of the reaction inhibitor (ruthenium precursor) comprises ruthenium (Ru).
It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to have modified the reaction inhibitor used in Givens et al. to have comprised ruthenium, as taught by Chen et al. The reaction inhibitor Ru(EtCp)₂ of Chen et al. would, in combination, selectively adsorb to the metal surface (also ruthenium) provided by Givens et al., but not insulating surfaces, allowing more control of where exactly the ALD deposits and conversion into metal without any impurities left at the interface.
Regarding claim 7, Givens et al. in view of Chen et al. teaches the method of claim 5.
Givens et al. teaches the reaction inhibitor chemistry, but does not explicitly teach wherein the organic ligand comprises a C5-C--10 carbocyclic group unsubstituted or substituted with at least one C1-C5 alkyl group or at least one C1- C5 alkoxy group.
Chen et al., however, teaches wherein the organic ligand (ethylcyclopentadienyl group) comprises a C5-C10 carbocyclic group (cyclopentadienyl ring, C₅H₅⁻) substituted with at least one C1-C5 alkyl group (ethyl).
It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to have modified the reaction inhibitor of Givens et al. to comprise an organic ligand comprising a substituted carbocyclic group, as taught by Chen et al. The cyclopentadienyl ring lies flat on the ruthenium surface, thus blocking ALD growth on that region.
Regarding claim 8, Givens et al. in view of Chen et al. teaches the method of claim 7.
Givens et al. teaches the reaction inhibitor chemistry, but does not explicitly teach wherein the carbocyclic group comprises cyclopentadiene (Cp), cyclohexadiene (CHD), cyclooctadiene (COD), or benzene (Ph).
Chen et al., however, teaches wherein the carbocyclic group (cyclopentadienyl ring, C₅H₅⁻) comprises cyclopentadiene (Cp).
It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to have replaced the organic ligand of Givens et al. to have comprised a carbocyclic group, specifically Cp, as taught by Chen et al. Cp rings are structurally planar and would thus lie flat and block reactant/precursor pairs from landing on ruthenium surfaces, unlike the non-cyclic ligands of Givens et al.
Regarding claim 9, Givens et al. in view Chen et al. teaches the method of claim 5.
Givens et al. teaches wherein the second material is a metal conductor ([0082]), but does not teach wherein the reaction inhibitor comprises a metal complex in which an organic ligand is coupled to a central metal, and wherein the second material and the central metal comprise a same metal.
Chen et al., however, teaches wherein the reaction inhibitor (ruthenium precursor) comprises a metal complex ([0084], bis(ethylcyclopentadienyl)ruthenium(II)) in which an organic ligand (ethylcyclopentadienyl group) is coupled to a central metal (ruthenium(II)).
It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to have combined the reaction inhibitor Ru(EtCp)₂ of Chen et al., comprising a ruthenium central metal, with the ruthenium metal conductor of Givens et al. Using the same metal reduces impurities left at interface when converted from the inhibition layer to a metal layer, without need for a separate inhibitor-removal step.
Regarding claim 10, Givens et al. teaches the method of claim 1.
Givens et al. teaches the reaction inhibitor chemistry, but does not teach wherein the reaction inhibitor comprises M((R)nCp)2, M comprises copper (Cu), aluminum (AI), tungsten (W), cobalt (Co), silver (Ag), gold (Au), platinum (Pt), iridium (Ir), rhodium (Rh), or ruthenium (Ru), R comprises methyl, ethyl, iso-propyl, or tert-butyl, and n is one of integers from 0 to 5.
Chen et al., however, teaches wherein the reaction inhibitor (ruthenium precursor) comprises M((R)nCp)2 (bis(ethylcyclopentadienyl)ruthenium(II)), M comprises ruthenium (Ru), R comprises ethyl, and n is one of integers (1) from 0 to 5.
It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to have used Ru(EtCp)₂ of Chen et al. as the reaction inhibitor in the method of Givens et al. Chen et al. provides a reaction inhibitor Ru(EtCp)₂ that would selectively adsorb on the ruthenium of Givens et al., blocking deposition selectively and converting to ruthenium metal when exposed to an oxidizing reactant.
Regarding claim 12, Givens et al. teaches the method of claim 1.
Givens et al. teaches wherein the forming the first reaction inhibition layer (passivation layer 206) comprises alternately supplying the reaction inhibitor onto the substrate (FIG. 2A, combination of first and second surfaces 204 + 202) and supplying a third reactant ([0066], third reactant 108) onto the substrate one or more times, and then supplying the reaction inhibitor onto the substrate (FIG. 3).
Givens et al. does not teach wherein the reaction inhibitor comprises a metal complex which comprises a central metal and an organic ligand comprising a substituent, and wherein the third reactant reacts with the organic ligand to convert the substituent.
Chen et al., however, teaches wherein the reaction inhibitor (ruthenium precursor) comprises a metal complex which comprises a central metal (ruthenium(II)) and an organic ligand (ethylcyclopentadienyl group) comprising a substituent (ethyl),
It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to have supplied the reaction inhibitor and third reactant in the method of Givens et al. and to have used a substituted metal complex as taught by Chen et al. Alternating the inhibitor of Chen et al. with the third reactant of Givens et al. improves surface coverage. Furthermore, reacting the organic ligand substituents of Chen et al. with the third reactant of Givens et al. shrinks the substituents, which allows more inhibitor molecules to pack/densify the inhibitor layer surface, preventing unwanted deposition where there would be gaps otherwise and thus increasing selectivity.
Claims 14 and 17-19 are rejected under 35 U.S.C. 103 as being unpatentable over Mountsier et al. (US 20150380302 A1) in view of Trapp et al. (US 20200235004 A1) and Givens et al. (US 20210301391 A1).
Regarding claim 14, Mountsier et al. in view of Trapp et al. and Givens et al. teaches a method of forming (FIG. 2A-2D) an interconnect of a semiconductor device. Mountsier et al. teaches the method comprising:
providing a substrate (substrate 101) comprising an interlayer insulating layer (second ILD layer 109), wherein the interlayer insulating layer comprises a via hole (via 111) configured to expose a lower metal layer ([0008], ruthenium liner within copper lines 107) and a trench (112) on the via hole, and the trench comprises a first region (upper-inner regions of via opening) connected to the via hole below the trench and a second region (straight lower-inner regions of via opening) configured to expose the interlayer insulating layer;
selectively forming a first reaction inhibition layer (diffusion barrier layer 110) on the lower metal layer using a reaction inhibitor ([0046], self-assembled monolayer) selectively adsorbed ([0048]) on the lower metal layer;
selectively forming a diffusion barrier layer (dielectric barrier layer 113) on an upper surface (layer tracing across top surface of 109) of the interlayer insulating layer and on an exposed portion (lining the inner surfaces of via opening) of the interlayer insulating layer; and
forming an upper metal layer (copper layer 115) in the via hole and the trench in which the diffusion barrier layer is formed.
Mountsier et al. is silent to teach using a first precursor and a first reactant, wherein the first reactant reacts with the first precursor to form an atomic layer, and does not react with the reaction inhibitor to form the atomic layer; converting the first reaction inhibition layer into a first metal layer using a second reactant which reacts with the reaction inhibitor to form the atomic layer; and forming an upper metal layer in the via hole and the trench in which the first metal layer is also formed.
However, Trapp et al. teaches using a first precursor ([0031], titanium tetrachloride) and a first reactant ([0031], ammonia), wherein the first reactant reacts with the first precursor to form an atomic layer ([0035], liner material 110); and converting the first reaction inhibition layer ([0055], first liner material 207) into a first metal layer (first liner structures 211) using a second reactant ([0039], oxygen plasma).
And Givens et al. further teaches wherein the first reactant does not react with ([0085]) the reaction inhibitor to form the atomic layer; and using a second reactant which reacts ([0088]) with the reaction inhibitor to form the atomic layer.
It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to have modified the interconnect method of Mountsier et al. to use the ALD diffusion barrier deposition approach of Trapp et al. and the inhibitor conversion step of Givens et al.
Selectively forming a barrier layer only where needed as taught in Trapp et al. and converting the inhibition layer (on the via bottom) into a metal layer using an inhibitor that doubles as a metal precursor as taught by Givens et al., keeps the series resistance low and conductive at the via bottom, as addressed by Mountsier et al.
Regarding claim 17, Mountsier et al. in view of Trapp et al. and Givens et al. teaches the method of claim 14. Mountsier et al. does not teach wherein the first precursor comprises TiCl4, Ti(NMe2)4(TDMAT), TaCl5, or Ta(OEt)2. Trapp et al., however, teaches wherein the first precursor comprises TiCl4 ([0031]).
It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to have used a first precursor TiCl4 taught by Trapp et al. in the method of Mountsier et al. and Givens et al. TiCl4 of Trapp et al. comprises titanium and provides as an effective ALD precursor that Mountsier et al. requires to selectively form a titanium-based diffusion barrier on insulating surfaces without depositing at the via bottom and reduce unwanted residue while still filling the interconnect structure.
Regarding claim 18, Mountsier et al. in view of Trapp et al. and Givens et al. teaches the method of claim 14. Mountsier et al. does not teach wherein the first reactant comprises water (H20), ammonia (NH3), or hydrogen (H2), and wherein the second reactant comprises oxygen (02).
Trapp et al., however, teaches wherein the first reactant comprises ammonia (NH3) ([0031]) and wherein the second reactant comprises oxygen (02) (0039], oxygen plasma).
It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to have used ammonia and oxygen as the first and second reactant as taught by Trapp et al. in the method of Mountsier et al. and Givens et al. The ammonia of Trapp et al. provides Mountsier et al. with a reactant that forms the barrier layer on insulating surfaces while leaving the via bottom metal intact by reacting with TiCl4 to form the barrier while O2 separately converts the inhibition layer into a metal layer at the via bottom, which maintains the low-resistance interconnect that Mountsier et al. seeks to achieve.
Regarding claim 19, Mountsier et al. in view of Trapp et al. and Givens et al. teaches the method of claim 14. Mountsier et al. teaches wherein the diffusion barrier layer (dielectric barrier layer 113) comprises tantalum nitride ([0004]).
Claim 11 is rejected under 35 U.S.C. 103 as being unpatentable over Givens et al. (US 20210301391 A1) in view of Trapp et al. (US 20200235004 A1).
Regarding claim 11, Givens et al. teaches the method of claim 1.
Givens et al. teaches wherein the second reactant comprises oxygen (02) ([0043]), but does not teach wherein the first reactant comprises water (H20), ammonia (NH3), or hydrogen (H2). However, Trapp et al. teaches wherein the first reactant comprises ammonia (NH3) ([0031]).
It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to have combined the second reactant of Givens et al. comprising oxygen with the first reactant of Trapp et al. comprising ammonia. The first reactant comprising ammonia in Trapp et al. forms a barrier layer on insulating surfaces while leaving the via bottom metal intact, as O2 separately converts the inhibition layer into a metal layer at the via bottom, achieving a low-resistance interconnect fabrication.
Claim 13 is rejected under 35 U.S.C. 103 as being unpatentable over Givens et al. (US 20210301391 A1) in view of Chen et al. (US 20190185993 A1) and Trapp et al. (US 20200235004 A1).
Regarding claim 13, Givens et al. in view of Chen et al. teaches the method of claim 12. Givens et al. teaches the third reactant ([0086], as nitrogen reactant 108), but does not teach the first reactant comprise a same material. Trapp et al., however, teaches the first reactant ([0031], NH3) comprise a same material (nitrogen).
It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to have used the first reactant of Trapp et al. comprising ammonia with the third/nitrogen reactant of Givens et al, both of which comprise the same material (nitrogen). The third reactant of Givens et al. would remove or shrink ligands on the inhibitor of Chen et al. to increase coverage/selectivity, as the first reactant grows a film only where the inhibitor does not block it.
Claims 15, 16, and 20 are rejected under 35 U.S.C. 103 as being unpatentable over Mountsier et al. (US 20150380302 A1) in view of Trapp et al. (US 20200235004 A1), Givens et al. (US 20210301391 A1), and Chen et al. (US 20190185993 A1).
Regarding claim 15, Mountsier et al. in view of Trapp et al. and Givens et al. teaches the method of claim 14. Mountsier et al. does not teach wherein the reaction inhibitor comprises a metal complex comprising a central metal and an organic ligand, wherein the central metal comprises copper (Cu), aluminum (AI), tungsten (W), cobalt (Co), silver (Ag), gold (Au), platinum (Pt), iridium (Ir), rhodium (Rh), or ruthenium (Ru), and wherein the organic ligand comprises cyclopentadiene (Cp), cyclohexadiene (CHD), cyclooctadiene (COD), or benzene (Ph) which is unsubstituted or substituted with at least one C1-C5 alkyl group or at least one C1-C5 alkoxy group..
Chen et al., however, teaches wherein the reaction inhibitor ([0084], ruthenium precursor) comprises a metal complex comprising a central metal (ruthenium (Ru)) and an organic ligand (ethylcyclopentadienyl group), wherein the central metal comprises ruthenium (Ru), and wherein the organic ligand (ethylcyclopentadienyl group) comprises cyclopentadiene (Cp) which is substituted with at least one C1-C5 alkyl group (ethyl).
It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to have modified the method of Mountsier et al. to use a ruthenium-based metal complex with a cyclopentadienyl-based organic ligand as the reaction inhibitor. The ruthenium metal complex of Chen et al. would selectively adsorb on the ruthenium metal surface of Mountsier et al. (and not adsorb on insulating surfaces), thus blocking the via bottom from ALD deposition and increasing selectivity in the interconnect structure of Mountsier et al.
Regarding claim 16, Mountsier et al. in view of Trapp et al., Givens et al., and Chen et al. teaches the method of claim 15.
Mountsier et al. teaches the lower metal layer ([0008], ruthenium liner within copper lines 107), but does not teach wherein the central metal of the reaction inhibitor comprises a same metal as a metal of the lower metal layer. Chen et al., however, teaches the central metal (ruthenium(Ru)).
It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to have chosen and combined the reaction inhibitor taught by Chen et al., comprising a central metal made of ruthenium, with the liner metal at the via bottom of Mountsier et al. Matching the material allows for a cleaner conversion of the inhibition layer to additional ruthenium metal, devoid of impurities being left, which keeps the via bottom of Mountsier et al. conductive and low resistance.
Regarding claim 20, Mountsier et al. in view of Trapp et al. and Givens et al. teaches the method of claim 14. Givens et al. teaches wherein the forming of the first reaction inhibition layer (passivation layer 206) comprises alternately supplying the reaction inhibitor onto the substrate (FIG. 2A, combination of first and second surfaces 204 + 202) and supplying a third reactant ([0066], third reactant 108) onto the substrate one or more times, and then supplying the reaction inhibitor onto the substrate (FIG. 3).
Givens et al. does not teach wherein the reaction inhibitor comprises a metal complex which comprises a central metal and an organic ligand comprising a substituent, and wherein the third reactant reacts with the organic ligand to convert the substituent.
Chen et al., however, teaches wherein the reaction inhibitor (ruthenium precursor) comprises a metal complex which comprises a central metal (ruthenium(II)) and an organic ligand (ethylcyclopentadienyl group) comprising a substituent (ethyl).
It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to have supplied the reaction inhibitor and third reactant of Givens et al. and to have used a substituted metal complex as taught by Chen et al in the method of Mountsier et al. Alternating the inhibitor of Chen et al. with the third reactant of Givens et al. improves surface coverage of the inhibition layer. Furthermore, reacting the organic ligand substituents of Chen et al. with the third reactant of Givens et al. allows more inhibitor molecules onto the surface, preventing unwanted barrier layer growth on the via bottom metal in the interconnect of Mountsier et al.
Conclusion
Any inquiry concerning this communication or earlier communications from the examiner should be directed to JEANNE M KIM whose telephone number is (571)272-8768. The examiner can normally be reached Monday-Thursday 8:00-6:00.
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If attempts to reach the examiner by telephone are unsuccessful, the examiner’s supervisor, Leonard Chang can be reached at (571) 270-3691. The fax phone number for the organization where this application or proceeding is assigned is 571-273-8300.
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/JEANNE MYON KIM/Examiner, Art Unit 2898
/Leonard Chang/Supervisory Patent Examiner, Art Unit 2898
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