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 .
This Office action is in response to Amendments filed 4/14/2026.
Claim Rejections - 35 USC § 103
The text of those sections of Title 35, U.S. Code not included in this action can be found in a prior Office action.
Claims 1-12, 21, 22, and 24-27 is/are rejected under 35 U.S.C. 103 as being unpatentable over Haba (US 8,580,607 B2) in view of Hu et al. (US 2018/0005939 A1).
Regarding claim 1, Haba discloses a redistribution layer structure (Fig. 1, using an orientation opposite of that shown in Fig. 1), comprising:
a metal feature (112 and 117) disposed over a die (120) and comprising a lower metal pattern (112A) and an upper metal pattern (117A) over the lower metal pattern; and
a polymer layer (114) surrounding the metal feature;
wherein a lateral dimension of the lower metal pattern is greater than a lateral dimension of the upper metal pattern.
Haba does not disclose a nitridized metal layer formed from metal included in the lower metal pattern as claimed.
However, it was well-known in art to form barrier layers from nitridized metal layers (214 in the right side of Fig. 2 of Hu) formed from metal which was included in the underlying metal layer and disposed only between the underlying and overlying metal patterns (see Fig. 2 of Hu).
There was a benefit to forming a nitridized metal layer as such in that it decreases electromigration of metal atoms between interconnects.
It would have been obvious to one having ordinary skill in the art at the time the invention was filed to incorporate a nitridized metal layer as disclosed by Hu into the device of Haba such that it is formed by nitridizing from metal which was included in the lower metal pattern of Haba for this benefit.
Hu discloses that the nitridized metal layer has a nitrogen atom content of “a few atomic % of N” (¶ 0029) with a specific example of “above 5 at %” (claim 10). Since the example “above 5 at %” is close to the range “1-5 at%”, a prima facie case of obviousness exists (MPEP § 2144.05(I)).
Regarding claim 2, the lateral dimension of the lower metal pattern is different from a lateral dimension of the nitridized metal layer (compare to Fig. 2 of Hu which shows the nitridized metal layer to have a different lateral dimension that the corresponding metal pattern).
Regarding claim 3, Hu discloses that an edge of the nitridized metal layer is aligned with an edge of the upper metal pattern (see Fig. 2).
Regarding claim 4, Hu discloses that the nitridized metal layer is in physical contact with the lower metal pattern (see Fig. 2) and will be in contact with the upper metal pattern in the combination (see 1 of Haba).
Regarding claim 5, Hu does not disclose the specific thickness of the nitridized metal layer.
However, there is motivation in that too thin of a nitridized metal layer would not sufficiently block the migration of metal atoms and too thick of a nitridized metal layer will interfere with the desired conductivity of the component.
As such, it would have been obvious to one or ordinary skill in the art at the time of filing to that the thickness of the nitridized metal layer is a result effective variable to be optimized and it has been held that discovering an optimum value of a result effective variable involves only routine skill in the art. (See MPEP § 2144.05 (II) (A) and (B)).
Therefore, it would have been obvious to one having ordinary skill in the art to form the thickness of the nitridized metal layer to be within the claimed range.
Regarding claim 6, Haba further discloses wherein a seed layer (117 contact 105 in Fig. 1) is disposed under the lower metal pattern, and a side edge of the seed layer is protruded outward from a side edge of the lower metal pattern (see Fig. 1).
Regarding claim 7, Haba discloses a semiconductor package (Fig. 1, using an orientation opposite of that shown in Fig. 1), comprising:
at least one die (120); and
a redistribution layer structure (112 and 117) disposed over and electrically connected to the at least one die and comprising at least one metal feature (112 and 117),
wherein the at least one metal feature comprises a lower seed layer (117 contact 105), a metal line (112A), and a metal via (117A) sequentially stacked and the at least one metal feature is embedded by a single polymer layer (114).
Haba does not disclose an upper seed layer as claimed.
However, it is well-known in the art to place seed layers (216 in Fig. 2 of Hu, ¶ 0032) between metal lines and metal vias.
There is a benefit to placing seed layers as such in that it decreases electromigration of metal atoms between the metal line and metal via.
It would have been obvious to one having ordinary skill in the art at the time of the invention to incorporate an upper seed layer between the metal line and metal via of Haba for this benefit.
The resulting device of the combination will have the lower seed layer and upper seed layer comprising different materials (¶ 0023 of Hu and Col. 9, Lines 1-17 of Haba) and have the upper seed layer being a nitridized copper layer which has a single-layer structure and is only disposed between the metal layer and the metal via (compare Fig. 2 of Hu and Fig. 1 of Haba).
Hu discloses that the nitridized metal layer has a nitrogen atom content of “a few atomic % of N” (¶ 0029) with a specific example of “above 5 at %” (claim 10). Since the example “above 5 at %” is close to the range “1-5 at%”, a prima facie case of obviousness exists (MPEP § 2144.05(I)).
Regarding claim 8, Hu discloses that an edge of the upper seed layer is aligned with an edge of the component which corresponds to metal via (see Fig. 2).
Regarding claim 9, Hu discloses that the nitridized metal layer is in physical contact with the metal line and metal via in the device of the combination (compare Fig. 2 of Hu and Fig. 1 of Haba).
Regarding claim 10, Hu does not disclose the specific thickness of the upper seed layer.
However, there is a benefit to form it as only a small percentage of the thickness of the metal lines and vias so as not to interfere with the desired electrical conductivity of the device.
As such, it would have been obvious to one having ordinary skill in the art to have the thickness of the upper seed layer be only a small percentage of the thickness of the lower seed layer for this reason.
Regarding claim 11, Hu does not disclose the specific thickness of the upper seed layer.
However, there is a benefit to form it as only a small percentage of the thickness of the metal lines and vias so as not to interfere with the desired electrical conductivity of the device.
As such, it would have been obvious to one having ordinary skill in the art to have the thickness of the upper seed layer be only a small percentage (i.e., less than 20%) of the thickness of the lower seed layer for this reason.
Regarding claim 12, Haba further discloses wherein a side edge of the lower seed layer is protruded outward from a side edge of the metal line (see Fig. 1).
Regarding claim 21, Haba discloses a semiconductor package (Fig. 2), comprising:
two dies (102) laterally disposed; and
a redistribution layer structure (sets of 112 and 117 in Fig. 1) disposed over and electrically connected to the two dies and comprising an “initial” metal feature (112A) and a second copper feature (117 above) disposed over and electrically connected to the “initial” metal feature, and a first seed layer (112B) underlying the “initial” metal feature;
wherein the features are embedded by a single polymer layer (114)
Haba does not disclose a second seed layer as claimed.
However, it is well-known in the art to place seed layers (216 in Fig. 2 of Hu, ¶ 0032) between metal lines and metal vias.
There is a benefit to placing seed layers as such in that it decreases electromigration of metal atoms between the metal line and metal via.
It would have been obvious to one having ordinary skill in the art at the time of the invention to incorporate a second seed layer between the “initial” metal feature of Haba and underlying the second copper feature directly above for this benefit.
The resulting device of the combination will include a first copper feature (“Cu intermetallic” 214 in Fig. 2, ¶ 0034 of Hu) disposed beneath and electrically connected to the second copper feature with the first seed layer underlying the first copper feature and the second seed layer being a single-layer of nitridized copper in contact with the first copper feature and the second copper feature (compare Fig. 2 of Hu and Fig. 1 of Haba).
Hu does not disclose the specific thickness of the second seed layer.
However, there is a benefit to form it as only a small percentage of the thickness of the metal lines and vias so as not to interfere with the desired electrical conductivity of the device.
As such, it would have been obvious to one having ordinary skill in the art to have the thickness of the second seed layer be only a small percentage of the thickness of the first seed layer for this reason.
Hu discloses that the nitridized metal layer has a nitrogen atom content of “a few atomic % of N” (¶ 0029) with a specific example of “above 5 at %” (claim 10). Since the example “above 5 at %” is close to the range “1-5 at%”, a prima facie case of obviousness exists (MPEP § 2144.05(I)).
Regarding claim 22, in the device of such a combination, the first and second seed layers will comprise different materials (¶ 0023 of Hu and Col. 9 Lines 1-17 of Haba).
Regarding claim 24, the first copper feature is a metal line (as it is metal in a line interconnecting multiple components) and the second copper feature is a metal via.
Regarding claim 25, the second seed layer is nitridized from metal included in the first copper feature (¶¶ 0032-33 of Hu).
Regarding claim 26, an edge of the second seed layer (top edge) is aligned with an edge of the second copper feature (bottom edge).
Regarding claim 27, a side edge of the second seed layer (right edge) protrudes outward from a side edge of the second copper feature (right edge; see Fig. 1 of Hu).
Claims 13 is/are rejected under 35 U.S.C. 103 as being unpatentable over Haba (US 8,580,607 B2) in view of Hu et al. (US 2018/0005939 A1) as applied to claim 7, above, and further in view of Chiu (US 2014/0225258 A1).
Regarding claim 13, Haba discloses that the upper seed layer comprises nitridized copper (¶ 0023). Hu does not disclose that the lower seed layer comprises titanium and copper.
Hu differs from the claimed invention by the substitution of titanium and copper for the lower seed layer with a different material. However, titanium and copper and the corresponding function of being used as a seed layer was known in the art (¶ 0020 of Chiu). As such, it would have been obvious to one having ordinary skill in the art before the Application's effective filing date to have substituted the known materials of titanium and copper as taught by Chu for the materials of Hu and the results of the substitution would have been predictable as a seed layer. (see MPEP § 2143(I)(B)).
Claims 23 is/are rejected under 35 U.S.C. 103 as being unpatentable over Haba (US 8,580,607 B2) in view of Hu et al. (US 2018/0005939 A1) as applied to claim 21, above, and further in view of Chiu (US 2014/0225258 A1).
Regarding claim 23, Haba does not disclose that the first seed layer comprises titanium and copper.
Haba differs from the claimed invention by the substitution of titanium and copper for the lower seed layer with a different material. However, titanium and copper and the corresponding function of being used as a seed layer was known in the art (¶ 0020 of Chiu). As such, it would have been obvious to one having ordinary skill in the art before the Application's effective filing date to have substituted the known materials of titanium and copper as taught by Chu for the materials of Haba and the results of the substitution would have been predictable as a seed layer. (see MPEP § 2143(I)(B)).
Response to Arguments
Applicant's arguments filed 4/14/2026 have been fully considered but they are not persuasive.
Applicant argues that Hu’s disclose of above 5% does not render obvious the claimed range of 1-5%. This argument is not persuasive as above 5% is close enough to 1-5% to render the range obvious. Compare to In re Brandt, 886 F.3d 1171, 1177, 126 USPQ2d 1079, 1082 (Fed. Cir. 2018) (the court found a prima facie case of obviousness had been made in a predictable art wherein the claimed range of "less than 6 pounds per cubic feet" and the prior art range of "between 6 lbs./ft3 and 25 lbs./ft3" were so mathematically close that the difference between the claimed ranges was virtually negligible absent any showing of unexpected results or criticality.).
Regarding claims 6, 12, and 27, Applicant’s amendments do not overcome the rejections as discussed above.
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.
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/C.A.C/Examiner, Art Unit 2815
/JOSHUA BENITEZ ROSARIO/Supervisory Patent Examiner, Art Unit 2815
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