The present application, filed on or after March 16, 2013, is being examined under the first inventor to file provisions of the AIA .
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.
DETAILED ACTION
A request for continued examination under 37 CFR 1.114, including the fee set forth in 37 CFR 1.17(e), was filed in this application after final rejection. Since this application is eligible for continued examination under 37 CFR 1.114, and the fee set forth in 37 CFR 1.17(e) has been timely paid, the finality of the previous Office action has been withdrawn pursuant to 37 CFR 1.114. Applicant's submission filed on 4/3/26 has been entered. Claims 1, 15, 19, and 24 have been amended, and claims 7, 8, 10, and 11 canceled. Claims 1 – 3, 5, 6, 9, and 12 – 25 are pending.
Response to Amendments / Arguments
Applicant’s arguments regarding the previously raised claim rejections under 35 USC 103 have been fully considered but they are moot in view of the new grounds of rejections, as necessitated by Applicant’s amendments. Specifically, the new limitations in independent claims 1, 15, and 24 define that the discrete metallic structures (plasmonic antennae) have a tapered width with a narrower end pointing upward and toward the laser of the PIC (as shown in Figs. 1 and 5B of the instant application). As correctly noted by Applicant (pp. 8 – 9 of the Remarks) in response to the Advisory Action of 3/11/26, discrete metallic structures 202 in Verschuuren are oriented such that their wider ends point towards a light source 102. Accordingly, the Examiner applies a reference by Luo et al (CN 112216761 A) that has been yielded by an updated prior art search and discloses discrete metallic structures (plasmonic antennae) that have tapered widths with their narrower end pointing upward and toward a light source. In combination with other prior art of record, Luo teaches expressly or renders obvious all of the limitations recited by the amended claims, as detailed below.
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 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.
The factual inquiries set forth in Graham v. John Deere Co., 383 U.S. 1, 148 USPQ 459 (1966), that are applied 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.
Claims 1, 5, 9, and 12 – 14 are rejected under 35 U.S.C. 103 as being unpatentable over Klamkin et al (US 2017/0207600 A1) in view of Luo et al (CN 112216761 A).
Regarding claim 1, Klamkin discloses (Figs. 6 and especially 23; Abstract; para. 0066, 0106, and 0111 – 0114) an optical interconnect, comprising (see annotated Figure A provided below and comprising Fig. 23):
a package substrate 602 (Si chip), wherein an optical waveguide 104 (Si waveguide layer) is embedded in the package substrate 602 (as seen in Fig. 6, the Si waveguide layer is sandwiched/embedded between the BOX layer 122 and the upper cladding layer 600 of the Si chip 602);
a photonics integrated circuit (PIC) 100 (Flip chip) over the package substrate 602 (Figs. 6 and 23), wherein the PIC comprises 100 a laser 106,120,2300 (as shown in Fig. 23; “In this particular embodiment, the laser cavity contains a back HR-coated mirror facet (120), a gain section (106), a DBR mirror section (2300)” at para. 0109, emphasis and numerals added) that is configured to be optically coupled (via vertical coupler 124) to the optical waveguide 104; and
a vertical coupler 124 disposed between the laser 106,120,2300 and the optical waveguide 104 and enabling out-of-plane coupling of laser-generated light into the optical waveguide 104.
Klamkin generally considers that the vertical coupler 124 can be implemented as a grating coupler (as shown in Figs. 6 and 23) or a plasmonic coupler structure (para. 0058 and 0102), but does not detail the latter. However, Luo discloses (Fig. 1, 3, and 6; Abstract; para. 0026 – 0031) a plasmonic coupler 4 (plasmonic nanostructure antenna) for out-of-plane coupling of an incident infrared lightwave 8 into a detection layer 2, the plasmonic coupler 4 formed by an array of discrete metallic structures (para. 0030 and 0031). Luo explicitly shows (Figs. 3 and 6) that individual ones of the discrete metallic structures have an upper width less than a lower width, the upper (narower) width disposed vertically between the lower width and the incident infrared lightwave 8 and receiving it.
It would have been obvious to a person of ordinary skill in the art before the effective filing date of the claimed invention that the vertical coupler 124 in Klamkin can be implemented as a plasmonic coupler, as generally suggested by Klamkin and detailed by Luo.
While Klamkin illustrates discrete structures/grates 124 vertically intervening between the laser (formed by two reflectors and a gain medium waveguide therebetween) and the optical waveguide (optically coupled to the output of the laser), Klamkin teaches that such discrete structures can be plasmonic nano-particles. Luo further details that plasmonic nano-particles can be made of a metal material (e.g., gold; para. 0030).
An optical interconnect of the Klamkin – Luo combination is illustrated in Figure A below which is produced from Fig. 23 of Klamkin by adding an upper cladding 600 (as in Fig. 6) and by implementing the grating couplers as an array of discrete metallic structures (plasmonic nano-particles), as generally suggested by Klamkin and detailed by Luo. They vertically intervene between the laser 106,120,2300 and the optical waveguide 104 and have their narrower ends pointing upwards and towards the laser of the PIC in order to improve collection efficiency of laser radiation by more efficient excitation of plasmons (according to Figs. 1, 3, 6 and para. 0013, 0031, and 0051 of Luo).
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Figure A. An optical interconnect of the Klamkin – Luo combination.
In light of the foregoing analysis, the Klamkin – Luo combination teaches expressly or renders obvious all of the recited limitations.
As further relevant comments, the following is noted:
(i) The limitations “vertically intervening” and “vertically between” are relative spatial terms and interpreted, according to the BRI, as defining positions relative to a direction extending away from package substrate.
(ii) While the structure in Fig. 23 comprises an externally-modulated laser with a modulator section 2302, Klamkin states (para. 0122 and 0124) that a directly-modulated laser is also a suitable choice in which case the modulator section 2302 is absent and the DBR mirror section 2300 can extend to the turning mirror 108.
Regarding claim 5, the Klamkin – Luo combination considers that the metallic structures comprise gold (“orderly evaporating the Ti/Au layer stacked together by electron beam evaporation method or magnetic control sputtering coating method to obtain the ultra-surface optical antenna layer” at para. 0046 of Luo; also para. 0050).
Regarding claim 9, Luo illustrates an embodiment (Fig. 2) with a 1D array of point-tipped triangularly-shaped metallic structures (with a zero upper width) and embodiments (Figs. 3 and 6) with trapezoidally/prismatically-shaped metallic structures. Hence, the Klamkin – Luo combination renders obvious that the metallic structures can be shaped as pyramids (with a zero upper width).
It is also noted that:
(i) It has been further held by the courts that a change in shape or configuration, without any criticality in operation of the device, is nothing more than one of numerous shapes that one of ordinary skill in the art will find obvious to provide based on the suitability for the intended final application. See In re Dailey, 149 USPQ 47 (CCPA 1976).In this case, selecting the claimed shape would have flown naturally to one of ordinary skill in the art as necessitated by the particular requirements of a given application (MPEP 2144 Supporting a Rejection Under 35 U.S.C. 103 [R-07.2015]; Section IV. CHANGES IN SIZE, SHAPE, OR SEQUENCE OF ADDING INGREDIENTS).
(ii) The instant application also considers a variety of suitable/workable shapes of the metallic structures (Figs. 3A, 5A, 5B, , 5C, and 5D; para. 0033, 0035, and 0058 of the instant specification).
Regarding claim 12, the Klamkin – Luo combination considers that the metallic structures can be spaced at a spacing (pitch p in Fig. 2 of Luo) that is within 10 – 100 nm (para. 0030 of Luo). Hence, the Klamkin – Luo combination considers a range that at leas overlaps with the recited range and a prima facie case of obviousness exists (MPEP 2144.05).
It is also noted that (i) the range limits depend on a particular application (a laser wavelength, selection of materials, etc); that (ii) the instant application does not provide any criticality for the exact value of the recited lower range limit; that (iii) it has been held that discovering the optimum or workable ranges of prior art involves only routine skill in the art (In re Aller, 105 USPQ 233); and that (iii) it has been held that "A recognition in the prior art that a property is affected by the variable is sufficient to find the variable result-effective." In re Applied Materials', Inc., 692 F.3d 1289, 1297 (Fed. Cir. 2012). It is well settled that it would have been obvious for an artisan with ordinary skill to develop workable or even optimum ranges for result-effective parameters. In re Boesch, 617 F.2d 272, 276 (CCPA 1980); see also In re Woodruff, 919 F.2d 1575, 1577-78 (Fed. Cir. 1990). In this regard, the Klamkin – Luo combination considers the spacing/pitch a result-effective parameter.
Regarding claim 13, the Klamkin – Luo combination considers that the package substrate comprises glass (BOX/SiO2 layer 122 in Fig. 23 of Klamkin).
Regarding claim 14, the Klamkin – Luo combination uses the metallic structures/nano-features are comprised in a plasmonic junction that has essential features that are similar/identical to those of the instant application and for the same purpose/benefit (out-of-plane coupling in/out of an optical waveguide) as those of the instant application, while it has been held that discovering the optimum or workable ranges (in this case, the length/width of the palsmonic junction/coupler) of prior art involves only routine skill in the art (In re Aller, 105 USPQ 233).
Additionally or alternatively, the Examiner took official notice in the Office Action of 7/2/25 that it was well known in the art that optical couplers (grating or plasmonic) have lengths on the order millimeters. Since Applicant has not traversed the official notice, the fact of common knowledge has become applicant admitted prior art. It would be well within ordinary skill in the art to find a suitable/workable length/width of the plasmonic junction/coupler.
Claims 2 and 3 are rejected under 35 U.S.C. 103 as being unpatentable over Klamkin in view of Luo, and further in view of “Ultracompact Graphene-Assisted Tunable Waveguide Couplers with High Directivity and Mode Selectivity” by Meng et al, Nature, Scientific Reports, 8:13362, pp. 1 – 11, 2018 (hereinafter Meng).
Regarding claims 2 and 3, the Klamkin – Luo combination does not teach that a graphene base over which the array of discrete metallic structures are disposed. However, Meng describes (Fig. 1 and 2; Abstract; pp. 1 – 5) a plasmonic coupler (plasmonic nanostructure antenna) for out-of-plane coupling of laser light into an optical waveguide (Si waveguide shown in Figs. 2a and 2b), wherein the plasmonic coupler comprises an array of discrete metallic structures (made of gold) that are disposed over a graphene base (Figs. 1a, 2a, and 2b). It would have been obvious to a person of ordinary skill in the art before the effective filing date of the claimed invention that the plasmonic coupler of the Klamkin – Luo combination can be modified, in accordance with the teachings of Meng, to include a graphene base over which the array of discrete metallic structures are disposed. The motivation for such graphene base is that the plasmonic coupler can be made electro-optically tunable (by a voltage applied to the graphene base) and tuned to different resonant wavelengths (Fig. 2e; Abstract; para. bridging pp. 4 – 5; last para. of Section “Conclusions” of Meng).
Claim 6 is rejected under 35 U.S.C. 103 as being unpatentable over Klamkin in view of Luo, and further in view of Alexander et al (US 7,515,269 B1).
Regarding claim 6, the Klamkin – Luo combination does not detail a possible/suitable process of making the metallic structures/nano-features and their resultant structure. However, Alexander teaches (6:52 – 7:5) that nano-features/nano-particles can be formed “from gold, silver, platinum, palladium, copper, and alloys thereof by reduction of aqueous metal salts in the presence of a passivating ligand”.
It would have been obvious to a person of ordinary skill in the art before the effective filing date of the claimed invention that the metal of the metallic (gold) structures/nano-features of the Klamkin – Luo combination can be coated with a passivation ligand as a result of a corresponding process, as taught by Alexander.
Claims 15 – 17, 22, and 23 are rejected under 35 U.S.C. 103 as being unpatentable over Klamkin in view of Luo, and further in view of Saito (US 2022/0234383 A1).
Regarding claim 15, as detailed above for claim , the teachings of Klamkin and Luo combine (see the arguments and motivation for combining, as provided above for claim 1) to teach expressly or render obvious all of the recited limitations defining an optical interconnect with a plasmonic junction comprising discrete metallic structures with a tapered width so that individual ones of the discrete metallic structures have an upper width less than a lower width, the upper width vertically between the lower width and the laser of the PIC. The Klamkin – Luo combination does not detail a possible/suitable process of forming a layer of the metallic (Au) structures/nano-features on the optical waveguide and, in particular, do not teach a process of layer transfer. However, Saito teaches (Figs. 1 – 4; para. 0038 – 0041) a process of layer transfer, the process comprising the steps of:
disposing a backing layer 2,3 over a layer 4 to be transferred to a package substrate 5 (Fig. 1);
transferring the layer 4 to the package substrate 5 (Fig. 2),
removing the backing layer 2,3 (Figs. 3 and 4).
It would have been obvious to a person of ordinary skill in the art before the effective filing date of the claimed invention that the layer of the metallic (Au) structures/nano-features on the optical waveguide, as contemplated by the Klamkin – Luo combination, can be fabricated by a process of layer transfer, as a suitable/workable process taught by Saito.
The Klamkin – Luo – Saito combination renders obvious a method of assembling an electronic package with optical interconnects, comprising:
disposing a backing layer over a plasmonic junction (according to Fig. 1 of Saito);
transferring the plasmonic junction to a package substrate (according to Fig. 2 of Saito), wherein the plasmonic junction is configured to be optically coupled to an optical waveguide in the package substrate (according to Fig. 23 of Klamkin);
removing the backing layer (Figs. 3 and 4 of Saito); and
placing a photonics integrated circuit (PIC) over the plasmonic junction, wherein the PIC comprises a laser that is configured to be optically coupled to the optical waveguide through the plasmonic junction (according to Fig. 23 of Klamkin), and wherein the array of discrete metallic structures of the plasmonic junction is vertically intervening between the laser and the optical waveguide (as seen in Figure A provided above for claim 1).
In light of the foregoing analysis, the Klamkin – Luo – Saito combination teaches expressly or renders obvious all of the recited limitations.
Regarding claims 16 and 17, Saito teaches, by way of example but not limitation, that the backing layer comprises PVA (polyvinyl alcohol) and that it is removed by being dissolved in water (para. 0041 and 0053). It would be well within ordinary skill to find an alternative pair(s) of a material for the backing layer and a solvent, such as PMMA and acetone. It is also noted that it has been held to be within the general skill of a worker in the art to select a known material on the basis of its suitability for the intended use as a matter of obvious design choice. See In re Leshin, 125 USPQ 416.
Regarding claim 22, the Klamkin – Luo – Saito combination teaches expressly or renders obvious all of the recited limitations, as detailed above for claim 13.
Regarding claim 23, the Examiner took official notice in the Office Action of 7/2/25 that a pick-and-place tool was well known in the art and commonly used for transferring layers with nano-structures. Since Applicant has not traversed the official notice, the fact of common knowledge has become applicant admitted prior art. Such a tool would be an obvious means to a person of ordinary skill for transferring the plasmonic junction.
Claims 18 – 21 are rejected under 35 U.S.C. 103 as being unpatentable over Klamkin in view of Luo, in view of Saito, and further in view of Meng.
Regarding claims 18 – 21, the teachings of Klamkin, Luo, Saito, and Meng combine (see the arguments and motivation for combining, as provided above for claims 1, 2, and 15) to teach expressly or render obvious all of the recited limitations, as detailed above for claims 2, 9, 3, and 12, respectively.
Claims 24 and 25 are rejected under 35 U.S.C. 103 as being unpatentable over Klamkin in view of Luo, in view of Meng, and further in view of Wu et al (US 2022/0179159 A1).
Regarding claim 24, the teachings of Klamkin, Luo, and Meng combine (see the arguments and motivation for combining, as provided above for claims 1 and 2) to consider (see Figure A provided above for claim 1):
a package substrate with an optical waveguide;
a photonics integrated circuit (PIC) with a laser that is configured to be optically coupled to the optical waveguide; and
a plasmonic junction between the laser and the optical waveguide, wherein the plasmonic junction comprises:
a (graphene) base (according to Meng); and
an array of discrete metallic (Au) structures/nano-features over the base, wherein the array of discrete metallic structures of the plasmonic junction is vertically intervening between the laser and the optical waveguide (as seen in Figure A), and wherein individual ones of the discrete metallic structures have an upper width less than a lower width (according to Luo), the upper width vertically between the lower width and the laser of the PIC.
While the Klamkin – Luo – Meng combination does not further detail a possible use of the contemplated module in an optoelectronic system with a board, Wu discloses (Fig. 2A; para. 0197) an optoelectronic system comprising a board 202 on which a plurality of electronic device and optical devices is mounted.
It would have been obvious to a person of ordinary skill in the art before the effective filing date of the claimed invention that the optoelectronic module of the Klamkin – Luo – Meng combination can be comprised into an optoelectronic system comprising a board on which the module is mounted, as a suitable/workable practical application taught by Wu, and enable a multi-functional optoelectronic system.
Regarding claim 25, the Klamkin – Luo – Meng – Wu combination teaches expressly or renders obvious all of the recited limitations, as detailed above for claim 12.
Conclusion
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/ROBERT TAVLYKAEV/Primary Examiner, Art Unit 2896
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