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 .
DETAILED ACTION
This office action is in response to the Applicant Election filled on 03/04/2026. Currently, claims 1-8 and 21-32 are pending in the application. Claims 9-20 have been withdrawn and cancelled from consideration.
Election/Restrictions
Applicant's election without traverse of Group I and Species IA (Figure 6), claims 1-8 and 21-32, in the reply filed on 03/04/2026 is acknowledged, there being no allowable generic or linking claim.
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 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 of this title, 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 1-2, 7-8, 21-24, 27-29 and 32 are rejected under 35 U.S.C. 103 as being obvious over NAGAI et al (US 20110049675 A1) in view of Fischer et al (US 20160343662 A1).
Regarding claim 1, Figures 1-10 of NAGAI disclose a method, comprising:
forming one or more semiconductor devices (500 and 600, [0043]) in an active device region of a semiconductor die (1000, [0042]);
forming one or more first metallization layers (110, [0044]) in a backend region above the one or more semiconductor devices;
forming one or more second metallization layers (160/220, [0048]) in the backend region in a periphery region of the semiconductor die, wherein the periphery region surrounds the active device region in a top view of the semiconductor die (please see Figure 1A);
forming a top dielectric layer (230, [0048]) above the backend region after forming the one or more first metallization layers and the one or more second metallization layers;
forming a barrier layer (251, [0067]) on the top dielectric layer;
forming a metal layer (261, [0067]) on the barrier layer;
forming a capping layer (271, [0067]) on the metal layer; and
performing an etch operation to etch the capping layer, the metal layer and the barrier layer to form a test pad (800, [0041]) on the top dielectric layer in the periphery region ([0068]).
NAGAI does not teach explicitly teach of performing a first etch operation to etch the capping layer and the metal layer to form a test pad on the top dielectric layer in the periphery region; and performing, after the first etch operation, a second etch operation to etch the barrier layer such that the barrier layer remains only under the test pad.
However, Fischer is a pertinent art which teaches a method for making a semiconductor structure, comprising: providing a workpiece; forming a barrier layer over the workpiece; forming a separation layer over the barrier layer; forming a conductive layer over the separation layer; and wet etching the conductive layer. Figures 1-6 of Fischer teach of using a first etching to etch the layer 230 and performing another each such as wet etching to etch a barrier layer 220 in the method forming the pad (310) ([0048], [0058] and [0060]).
Thus, it would have been obvious to try by one of ordinary skill in the art before the effective filing date of the claimed invention to use a method comprising performing a first etch operation to etch the capping layer and the metal layer to form a test pad on the top dielectric layer in the periphery region; and performing, after the first etch operation, a second etch operation to etch the barrier layer such that the barrier layer remains only under the test pad according to the teaching of Fischer without having any undercut issues ([0003] of Fischer) and for an improved shape and size of the pad in the device of NAGAI. Further, it has been held that choosing from a finite number of identified, predictable solutions such as two etching steps instead of one etching used to form the test pad in the device, with a reasonable expectation of success is obvious. KSR Int'l v. Teleflex Inc., 127 S.Ct. 1727 (2007).
Regarding claim 21, Figures 1-10 of NAGAI disclose a method, comprising:
forming one or more semiconductor devices (500 and 600, [0043]) in an active device region of a semiconductor die (1000, [0040]);
forming one or more first metallization layers (110, [0044]) in a backend region above the one or more semiconductor devices;
forming one or more second metallization layers (160/220, [0048]) in the backend region in a periphery region of the semiconductor die, wherein the periphery region surrounds the active device region in a top view of the semiconductor die (please see Figure 1A);
forming a top dielectric layer (230, [0048]) above the backend region after forming the one or more first metallization layers and the one or more second metallization layers;
forming a barrier layer (251, [0067]) on the top dielectric layer;
forming a metal layer (261, [0067]) on the barrier layer;
forming a capping layer (271, [0067]) on the metal layer; and
performing an etch operation to etch the capping layer, the metal layer and the barrier layer to form a test pad (800, [0041]) on the top dielectric layer in the periphery region ([0068]).
NAGAI does not explicitly teach of performing a first etch operation to etch the capping layer and the metal layer to form a test pad on the top dielectric layer in the periphery region, wherein the first etch operation comprises a dry etch operation; and performing, after the first etch operation, a second etch operation to etch the barrier layer such that the barrier layer remains only under the test pad.
However, Fischer is a pertinent art which teaches a method for making a semiconductor structure, comprising: providing a workpiece; forming a barrier layer over the workpiece; forming a separation layer over the barrier layer; forming a conductive layer over the separation layer; and wet etching the conductive layer. Figures 1-6 of Fischer teach of using a first etching to etch the layer 230 and performing another each such as wet etching to etch a barrier layer 220 in the method forming the pad (310) ([0048], [0058] and [0060]).
Thus, it would have been obvious to try by one of ordinary skill in the art before the effective filing date of the claimed invention to use a method comprising performing a first etch operation to etch the capping layer and the metal layer to form a test pad on the top dielectric layer in the periphery region, wherein the first etch operation comprises a dry etch operation; and performing, after the first etch operation, a second etch operation to etch the barrier layer such that the barrier layer remains only under the test pad according to the teaching of Fischer without having any undercut issues ([0003] of Fischer) and for an improved shape and size of the pad in the device of NAGAI. Further, it has been held that choosing from a finite number of identified, predictable solutions such as two etching steps instead of one etching used to form the test pad in the device, with a reasonable expectation of success is obvious. KSR Int'l v. Teleflex Inc., 127 S.Ct. 1727 (2007).
Regarding claim 27, Figures 1-10 of NAGAI disclose a method, comprising:
forming a dielectric layer (230, [0048]) above one or more metallization layers (160/220, [0048]) in a backend region of a semiconductor die (1000, [0042]), wherein the dielectric layer is formed in an active device region and in a periphery region of the semiconductor die (please see the Figure 1A);
forming a barrier layer (251, [0067]) on the dielectric layer;
forming a metal layer (261, [0067]) on the barrier layer;
forming a capping layer (271, [0067]) on the metal layer; and
performing an etch operation to etch the capping layer, the metal layer and the barrier layer to form a test pad (800, [0041]) on the top dielectric layer in the periphery region ([0068]).
NAGAI does not explicitly teach of performing a first etch operation to etch the capping layer and the metal layer to form a test pad on the dielectric layer in the periphery region; and performing, after the first etch operation, a second etch operation to etch the barrier layer, wherein a remaining portion of the barrier layer is under the test pad.
However, Fischer is a pertinent art which teaches a method for making a semiconductor structure, comprising: providing a workpiece; forming a barrier layer over the workpiece; forming a separation layer over the barrier layer; forming a conductive layer over the separation layer; and wet etching the conductive layer. Figures 1-6 of Fischer teach of using a first etching to etch the layer 230 and performing another each such as wet etching to etch a barrier layer 220 in the method forming the pad (310) ([0048], [0058] and [0060]).
Thus, it would have been obvious to try by one of ordinary skill in the art before the effective filing date of the claimed invention to use a method comprising performing a first etch operation to etch the capping layer and the metal layer to form a test pad on the top dielectric layer in the periphery region; and performing, after the first etch operation, a second etch operation to etch the barrier layer such that the barrier layer remains only under the test pad according to the teaching of Fischer without having any undercut issues ([0003] of Fischer) and for an improved shape and size of the pad in the device of NAGAI. Further, it has been held that choosing from a finite number of identified, predictable solutions such as two etching steps instead of one etching used to form the test pad in the device, with a reasonable expectation of success is obvious. KSR Int'l v. Teleflex Inc., 127 S.Ct. 1727 (2007).
Regarding claim 2, Figures 1-10 of NAGAI in view of Fischer teach that the method of claim 1, wherein the second etch operation comprises a wet etch operation using a wet etchant ([0048] of Fischer, the dry etching process may occur before the wet etching process).
Regarding claim 7, Figures 1-10 of NAGAI in view of Fischer teach that the method of claim 2, wherein an etch rate of the wet etchant for the barrier layer is greater than an etch rate of the wet etchant for the top dielectric layer (based on the steps in Figures 3-5 of Fischer wherein the lower layer of barrier layer is not etched).
Regarding claim 8, Figures 1-10 of NAGAI disclose a method of claim 1, wherein the second etch operation stops on the top dielectric layer (Figure 3A, dielectric is not etched).
Regarding claim 22, Figures 1-10 of NAGAI in view of Fischer teach that the method of claim 21, wherein the second etch operation comprises a wet etch operation using a wet etchant ([0048] of Fischer, the dry etching process may occur before the wet etching process).
Regarding claim 23, Figures 1-10 of NAGAI in view of Fischer do not explicitly teach that the method of claim 22, wherein an etch rate of the wet etchant for the barrier layer is greater than an etch rate of the wet etchant for the top dielectric layer.
However, it would have been obvious to one having ordinary skill in the art at the time of the invention was made to use the above claimed ranges in order to efficiently form the test pad with lower cost, since it has been held that where the general conditions of a claim are disclosed in the prior art, discovering the optimum or working range involves only routine skill in the art. In re Aller, 105 USPQ 233.
Regarding claim 24, Figures 1-10 of NAGAI disclose that the method of claim 21, wherein the barrier layer comprises at least one of: tantalum (Ta),tantalum nitride (TaN),titanium (Ti), or titanium nitride (TiN) ([0067], 251 is TiN).
Regarding claim 28, Figures 1-10 of NAGAI disclose that the method of claim 27, further comprising: removing the test pad (Figure 7A-7B) after performing the second etch operation; and depositing an additional metal layer (321 and 331, [0082]) over the dielectric layer and over the remaining portion of the barrier layer (250).
Regarding claim 29, Figures 1-10 of NAGAI disclose that the method of claim 28, further comprising etching the additional metal layer to form a redistribution pad on the remaining portion of the barrier layer, wherein the redistribution pad (312) is formed around ends of the remaining portion of the barrier layer (250) (Figure 9B teaches of having 312 around ends).
Regarding claim 32, Figures 1-10 of NAGAI in view of Fischer teach that the method of claim 27, wherein ends of the remaining portion of the barrier layer are recessed (Figures 3-5 of Fischer teaches of etching ends of a barrier layer 220).
Claims 3-6 are rejected under 35 U.S.C. 103 as being obvious over NAGAI et al (US 20110049675 A1) in view of Fischer et al (US 20160343662 A1) as applied to claims above, and further in view of TUNG et al (US 20220102200 A1).
Regarding claims 3-6, Figures 1-10 of NAGAI in view of Fischer do not explicitly teach that the method of claim 2, wherein the wet etchant comprises a combination of ammonium hydroxide (NH40H), hydrogen peroxide (H202), and water (H20), wherein the hydrogen peroxide comprises a greater concentration by weight of the wet etchant than the ammonium hydroxide. Or
The method of claim 2, wherein the wet etchant comprises a combination of hydrochloric acid (HCl) and nitric acid (HNO3), wherein the hydrochloric acid comprises a greater concentration by weight of the wet etchant than the nitric acid.
However, TUNG is a pertinent art which teaches a method for lithography patterning, wherein TUNG teaches that an etching process(es) may include a reactive ion etch or plasma etching system. The dry etching process may implement a hydrogen-comprising etch gas (e.g., H.sub.2 and/or CH.sub.4), a nitrogen-comprising etch gas (for example, N.sub.2 and/or NH.sub.3), a chlorine-comprising etch gas (for example, Cl.sub.2, CHCl.sub.3, CCl.sub.4, and/or BCl.sub.3), an oxygen-comprising etch gas (for example, O.sub.2), a fluorine-comprising etch gas (for example, F.sub.2, CH.sub.3F, CH.sub.2F.sub.2, CHF.sub.3, CF.sub.4, C.sub.2F.sub.6, SF.sub.6, and/or NF.sub.3), a bromine-comprising etch gas (e.g., Br, HBr, CH.sub.3Br, CH.sub.2Br.sub.2, and/or CHBr.sub.3), an iodine-comprising etch gas, other suitable etch gas, or combinations thereof. In some embodiments, the dry etching process can use a carrier gas to deliver the etch gas. The carrier gas includes nitrogen, argon, helium, xenon, other suitable carrier gas constituent, or combinations thereof. The wet etching process may implement a wet etchant solution that includes H.sub.2SO.sub.4 (sulfuric acid), H.sub.2O.sub.2 (hydrogen peroxide), NH.sub.4OH (ammonium hydroxide), HCl (hydrochloric acid), HF (hydrofluoric acid), DHF (diluted HF), HNO.sub.3 (nitric acid), H.sub.3PO.sub.4 (phosphoric acid), H.sub.2O (water) (which can be deionized water (DIW) or ozonated de-ionized water (DIWO.sub.3)), ozone (O.sub.3), other suitable chemicals, or combinations thereof ([0063]).
Thus, it would have been obvious to try by one of ordinary skill in the art before the effective filing date of the claimed invention to use the method as claimed above in order to etch the layers efficiently with lower cost, since it has been held that choosing from a finite number of identified, predictable solutions such as claimed used to form the device, with a reasonable expectation of success is obvious. KSR Int'l v. Teleflex Inc., 127 S.Ct. 1727 (2007). Further, it would have been obvious to one having ordinary skill in the art at the time of the invention was made to use the above claimed ranges since it has been held that where the general conditions of a claim are disclosed in the prior art, discovering the optimum or working range involves only routine skill in the art. In re Aller, 105 USPQ 233.
Allowable Subject Matter
Claims 25-26 and 30-31 are objected to as being dependent upon rejected base claims, but would be allowable if rewritten in independent form including all of the limitations of the base claims and any intervening claims.
The following is a statement of reasons for the indication of allowable subject matter:
Regarding claim 25, there is no prior art available nor obvious motivation to combine elements of prior art which teaches a method, comprising: “removing the test pad after performing the second etch operation; and forming a redistribution pad over the barrier layer in place of the test pad, wherein a bottom surface of the redistribution pad and a bottom surface of the barrier layer are co-planar” in combination with the limitations of the claims it depend on.
Regarding claim 26, this claim is allowable as it depends on an allowable claim.
Regarding claim 30, there is no prior art available nor obvious motivation to combine elements of prior art which teaches a method, comprising: “wherein etching the additional metal layer forms one or more recesses in the dielectric layer” in combination with the limitations of the claims it depend on.
Regarding claim 31, there is no prior art available nor obvious motivation to combine elements of prior art which teaches a method, comprising: “wherein a bottom surface of the redistribution pad and a bottom surface of the remaining portion of the barrier layer are co-planar” in combination with the limitations of the claims it depend on.
Examiner Notes
A reference to specific paragraphs, columns, pages, or figures in a cited prior art reference is not limited to preferred embodiments or any specific examples. It is well settled that a prior art reference, in its entirety, must be considered for all that it expressly teaches and fairly suggests to one having ordinary skill in the art. Stated differently, a prior art disclosure reading on a limitation of Applicant's claim cannot be ignored on the ground that other embodiments disclosed were instead cited. Therefore, the Examiner's citation to a specific portion of a single prior art reference is not intended to exclusively dictate, but rather, to demonstrate an exemplary disclosure commensurate with the specific limitations being addressed. In re Heck, 699 F.2d 1331, 1332-33,216 USPQ 1038, 1039 (Fed. Cir. 1983) (quoting In re Lemelson, 397 F.2d 1006, 1009, 158 USPQ 275, 277 (CCPA 1968)). In re: Upsher-Smith Labs. v. Pamlab, LLC, 412 F.3d 1319, 1323, 75 USPQ2d 1213, 1215 (Fed. Cir. 2005); In re Fritch, 972 F.2d 1260, 1264, 23 USPQ2d 1780, 1782 (Fed. Cir. 1992); Merck& Co. v. BiocraftLabs., Inc., 874 F.2d 804, 807, 10 USPQ2d 1843, 1846 (Fed. Cir. 1989); In re Fracalossi, 681 F.2d 792,794 n.1, 215 USPQ 569, 570 n.1 (CCPA 1982); In re Lamberti, 545 F.2d 747, 750, 192 USPQ 278, 280 (CCPA 1976); In re Bozek, 416 F.2d 1385, 1390, 163 USPQ 545, 549 (CCPA 1969).
Conclusion
Any inquiry concerning this communication or earlier communications from the examiner should be directed to KHAJA AHMAD whose telephone number is (571)270-7991. The examiner can normally be reached on Monday-Friday, 8:00 AM - 5:00 PM (Eastern Time).
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/KHAJA AHMAD/Primary Examiner, Art Unit 2813
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