/KIRSTEN D. ENDRESEN/ 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 .
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.
Response to Amendment
The Amendment filed on 04 August, 2026 has been fully considered and entered. In response to the amendment to claim 12, the previously raised claim objection is withdrawn.
Response to Arguments
Applicant’s arguments with respect to claim(s) 1-20 have been considered but are moot because the new ground of rejection does not rely on any reference applied in the prior rejection of record for any teaching or matter specifically challenged in the argument.
Claim Objections
Claim 10 is objected to because of the following informalities: “there no more” should be “there are no more”. Appropriate correction is required.
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.
Claim 9 is rejected under 35 U.S.C. 102(a)(1) as being anticipated by Toda (US 2009/0020690; hereinafter Toda).
Regarding claim 9: Toda disclosesAn optical device (Fig. 2B, solid state imaging device 100A) comprising: a substrate (Fig. 2B, substrate 102); a first set of ridges (see Annotated Fig. 2B, ridges a, b, c, d) separated by a first set of trenches (see Annotated Fig. 2B, trenches i, ii, iii, and iv), wherein widths of the first set of trenches and the first set of ridges are non-uniform (the widths of the identified ridges are shown to be non-uniform), such that widths of the first set of trenches have variation from an average width and widths of the first set of ridges have variation so that a first trench has a width that is narrower than two immediately adjacent trenches (trench ii is considered a first trench meeting this limitation), a second trench of the first set of trenches has a width that is wider than two immediately adjacent trenches (trench iii is considered a second trench meeting this limitation), and a ridge of the first set of ridges has a width that is narrower than two immediately adjacent ridges (ridge b meets this limitation, see dashed horizontal lines which are the same length, corresponding to the width of ridge b); and a second set of ridges (see Annotated Fig. 2B, ridges A, B, and C), wherein:the second set of ridges are disposed on the first set of ridges (annotated Fig. 2B shows this), such that the first set of ridges are between the substrate and the second set of ridges (annotated Fig. 2B shows this); and the second set of ridges are offset from the first set of ridges (annotated Fig. 2B shows this).
Annotated Fig. 2B:
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Claims 9-10 and 12 are rejected under 35 U.S.C. 102(a)(1) as being anticipated by Doany et al. (US Patent No. 9,411,106; hereinafter Doany).
Regarding claim 9: Doany disclosesAn optical device (Fig. 6A) comprising: a substrate (col. 6, lines 4-10); a first set of ridges separated by a first set of trenches (see ridges and trenches of Fig. 6A, grating 607), wherein widths of the first set of trenches and the first set of ridges are non-uniform (Fig. 6A shows this), such that widths of the first set of trenches have variation from an average width (Fig. 6A shows this) and widths of the first set of ridges have variation (Fig. 6A shows this) so that a first trench has a width that is narrower than two immediately adjacent trenches (see first trench in Annotated Fig. 6A), a second trench of the first set of trenches has a width that is wider than two immediately adjacent trenches (see second trench in Annotated Fig. 6A), and a ridge of the first set of ridges has a width that is narrower than two immediately adjacent ridges (see first ridge in Annotated Fig. 6A); and a second set of ridges (Fig. 6A, ridges of grating 605), wherein:the second set of ridges are disposed on the first set of ridges (Fig. 6A shows this), such that the first set of ridges are between the substrate and the second set of ridges (this arrangement is described in col. 6, lines 4-10); and the second set of ridges are offset from the first set of ridges (see dotted vertical lines in Fig. 6A, the second set of ridges are offset from the first set of ridges).
Annotated Fig. 6A:
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Regarding claim 10: Doany disclosesThe optical device of claim 9 (as applied above), wherein the first set of ridges forms a first grating (Fig. 6A shows this), and the first grating has a non-uniform spacing between ridges, and there are no more than two trenches between the first trench and the second trench (annotated Fig. 6A shows this).
Regarding claim 12: Doany disclosesThe optical device of claim 9 (as applied above), wherein: the first set of ridges are separated by a first set of trenches (Fig. 6A shows this), as part of a first grating; the first set of trenches are filled with an insulating material that has a lower refractive index than the first set of ridges (see col. 4, lines 15-17); the second set of ridges are separated by a second set of trenches (Fig. 6A shows this), as part of a second grating; the second set of ridges partially overlap the first set of ridges (see dotted vertical lines in annotated Fig. 6A); and the second set of ridges partially overlap the first set of trenches (see dotted vertical lines in annotated Fig. 6A), so that subwavelength structures are formed (see col. 4, lines 40-50; operating wavelength is 1.55 microns, whereas the gratings form subwavelength structures in the range of 620 nm-950 nm).
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 1-4, 7-8, and 11 are rejected under 35 U.S.C. 103 as being unpatentable over Doany et al. (US Patent No. 9,411,106; hereinafter Doany).
Regarding claim 1: Doany disclosesA system for optical communication, comprising: a waveguide (Fig. 6A, waveguide layer 606) having a core of higher refractive index material than a cladding (see col. 4, lines 54-58), the waveguide disposed on a substrate (see col. 6, lines 4-10), wherein the core is configured to guide light along a first propagation direction; and a coupler (see Fig. 6A and col. 5, lines 63-67) comprising: a first grating (Fig. 6A, grating 607) formed in the higher refractive index material, wherein: the first grating comprises a first set of ridges separated by a first set of trenches (Fig. 6A shows that grating 607 comprises a first set of ridges separated by a first set of trenches; and widths of the first set of ridges are non-uniform (Fig. 6a shows this), such that widths of the first set of ridges have variation from an average width so that a first ridge has a width that is narrower than two immediately adjacent ridges and a second ridge has a width that is wider than two immediately adjacent ridges (see annotated Fig. 6A below); and a second grating (Fig. 6A, grating 605), wherein: the second grating comprises a second set of ridges separated by a second set of trenches (Fig. 6A shows that grating 605 comprises a second set of ridges separated by a second set of trenches); the first set of ridges is between the substrate and the second set of ridges (according to the arrangement described in col. 6, lines 4-10, the first set of ridges is between the substrate and the second set of ridges); the second set of ridges partially overlap the first set of ridges (four sets of dotted vertical lines in annotated Fig. 6 show this); the second set of ridges partially overlap the first set of trenches (four sets of dotted vertical lines in annotated Fig. 6 show this).
Doany further discloses that the coupler is configured to guide light out of the waveguide (see col. 6, lines 19-22) in an alternative embodiment to the embodiment showing light coupled into the waveguide in Fig. 6A from a second propagation direction to a first propagation direction. However, based on the suggestion of Doany to couple light out of the waveguide using the grating coupler and based on the principle of optical reciprocity, when the grating is used according to the described embodiment having light from the two layers directed by the gratings toward detection circuits, they would be coupled along a second propagation direction that is not parallel with the first propagation direction when the coupler is configured to couple light out of the waveguide. Examiner further notes that since the Doany structure is capable of being used in this way, it could be considered an intended use of the grating, but since the alternative embodiment is suggested, one of ordinary skill in the art would be motivated to configure the device as an out-coupler in order to output light from a waveguide toward a detection circuit with low loss.
Regarding claim 2: Modified Doany teaches the system of claim 1, as applied above. Doany further suggests that grating couplers are useful for coupling light into single mode fibers (see col. 1, lines 25-30), and as described above, Doany suggests an alternative embodiment wherein light is coupled out from the coupler of Fig. 6A (see col. 6, lines 15-22). Based on these suggestions, it would have been obvious to one of ordinary skill in the art, before the effective filing date of the claimed invention, to reconfigure the grating coupler of Fig. 6 such that it couples light to a single mode fiber, being an optical fiber positioned to receive light along the second propagation direction, in order to provide out-coupling to an optical fiber with low loss.
Regarding claim 3: Modified Doany teaches the system of claim 1, as applied above. Doany fails to teach that the second propagation direction is orthogonal to the first propagation direction. However, the angle of light emission from the grating is a result effective variable, since it determines where the light couples out of the device relative to a detector. In order to out-couple light to a detector placed directly above the grating, it would have been obvious to one of ordinary skill in the art, before the effective filing date of the claimed invention, to further modify the Doany device such that the second propagation direction is orthogonal to the first propagation direction, since it has been held that where the general conditions of a claim are disclosed in the prior art, discovering the optimum or workable ranges involves only routine skill in the art (In re Aller, 105 USPQ 233), and since it has been held that discovering an optimum value of a result effective variable involves only routine skill in the art (In re Boesch, 617 F.2d 272, 205 USPQ 215 (CCPA 1980)).
Regarding claim 4: Modified Doany teachesThe system of claim 1, wherein the first ridge is immediately adjacent to the second ridge (annotated Fig. 6A shows this).
Regarding claim 7: Modified Doany teachesThe system of claim 1 (as applied above), wherein the first set of ridges, the second set of ridges, the first set of trenches, and the second set of trenches each have widths greater than or equal to 170 nm (see Fig. 3A-3B and col. 5, lines 10-20; since the maximum widths of each of the first set of ridges, the second set of ridges, the first set of trenches, and the second set of trenches half a TE-grating period and TM-grating period, as best shown in Fig. 1C, Doany discloses this feature).
Regarding claim 8: Doany discloses or suggests all of the limitations of claim 8, as applied above, but does not disclose that the coupler has a coupling efficiency of better than -2 dB. However, coupling efficiency is a result effective variable which one of ordinary skill in the art would seek to optimize and improve. Before the effective filing date of the present invention, a person of ordinary skill in the art would have found it obvious to optimize the coupling efficiency to be better than -2 dB, since it has been held that where the general conditions of a claim are disclosed in the prior art, discovering the optimum or workable ranges involves only routine skill in the art (In re Aller, 105 USPQ 233), and since it has been held that discovering an optimum value of a result effective variable involves only routine skill in the art (In re Boesch, 617 F.2d 272, 205 USPQ 215 (CCPA 1980)).
Regarding claim 11: Doany discloses the optical device of claim 10, as applied above. Doany further discloses that the grating 607 is the union of the TE and TM optimized gratings, which is optimized for periods at 620nm and 900nm with 50% duty cycle. The union grating forms a trench only where both of the optimized TE and TM gratings form trenches, but where either the TE or the TM optimized gratings form ridges, the union grating forms a ridge. Therefore, the maximum theoretical spacing between union grating trenches is 760nm, the average duty cycle is 100%-(50%*50%)=75% and the average period can be approximated as the average of the periods of the optimized TM and TE gratings, i.e. 760nm. The average spacing between trenches can therefore be approximated to be 570nm, which is an approximate value due to the finite size of the grating and manufacturing limitations preventing infinitesimal feature sizes. Doany therefore suggests a maximum spacing between immediately adjacent ridges being up to 133% of an average value of spacing between immediately adjacent trenches, overlapping the claimed range. This would suggest to one of ordinary skill in the art to prepare a grating according to the teachings of Doany having the feature wherein the non-uniform spacing is characterized by at least one spacing between immediately adjacent trenches having a width that is equal to or greater than 125% of an average value of spacing between immediately adjacent trenches.
In the case where the claimed ranges overlap or lie inside ranges disclosed by the prior art, a prima facie case of obviousness exists absent any evidence of (a) the criticality of the claimed range to produce new and unexpected results, and/or (b) the prior art teaching away from the claimed invention. Iron Grip Barbell Co., Inc. v. USA Sports, Inc., 392 F.3d 1317, 1322, 73 USPQ2d 1225, 1228 (Fed. Cir. 2004). See MPEP 2144.05 (I)(III).
In the present case, the prior art's range renders obvious the claimed range because the current invention fails to establish criticality of the claimed range, and one of ordinary skill would have expected the prior art to operate as disclosed when utilizing the claimed range. Moreover, there is no evidence to support that the prior art teaches away from the claimed invention.
Claims 14-16 and 19-20 are rejected under 35 U.S.C. 103 as being unpatentable over Doany et al. (US Patent No. 9,411,106; hereinafter Doany) in view of Kopp et al. (US 2010/0265504; hereinafter Kopp).
Regarding claim 14: Doany discloses an optical coupler comprising: a first set of trenches (see Fig. 6A, trenches of grating 607) and a first set of ridges (see Fig. 6A, ridges of grating 607) of a first grating (see Fig. 6A, grating 607) formed in a device layer (Fig. 6A, layer 606), wherein the widths of the first set of ridges have variation from an average width so that a first ridge has a width that is narrower than two immediately adjacent ridges and a second ridge has a width that is wider than two immediately adjacent ridges (see annotated Fig. 6A, first ridge and second ridge). Doany further discloses trenches being filled with a material having a lower refractive index than the device layer (see col. 4, lines 15-17), and an overlay material on the first set of ridges and on the material having a lower refractive index than the device layer (see Fig. 6A, layer 604 is an overlay material), including a second set of ridges (see Fig. 6A, ridges of grating 605) and a second set of trenches (see Fig. 6A, trenches of grating 605) forming a second grating (see Fig. 6A, grating 605) in the overlay material, wherein the second set of ridges partially overlap the first set of ridges and partially overlap the material in the first set of trenches (see Annotated Fig. 6A). Doany further discloses a method for fabricating an optical coupler using etching and filling techniques to form the gratings (see col. 3, lines 50-61). However, Doany fails to explicitly teach A method for fabricating an optical coupler, the method comprising: etching a first set of trenches in a device layer to form a first set of ridges of a first grating; and filling the first set of trenches with a material having a lower refractive index than the device layer; depositing an overlay material on the first set of ridges and on the material having a lower refractive index than the device layer; and etching a second set of trenches in the overlay material to form a second set of ridges of a second grating, wherein the second set of ridges partially overlap the first set of ridges and partially overlap the material in the first set of trenches.
However, Kopp teaches a method for forming two layers of gratings (see Figs. 5, 7-8, and 11 as well as paragraphs 0103-0111), including the steps of: etching a first set of trenches in a device layer to form a first set of ridges of a first grating (see paragraphs 0107-0108); and filling the first set of trenches with a material having a lower refractive index than the device layer (see paragraph 0110); depositing an overlay material on the first set of ridges and on the material having a lower refractive index than the device layer (see paragraph 0111); and etching a second set of trenches in the overlay material to form a second set of ridges of a second grating, wherein the second set of ridges partially overlap the first set of ridges and partially overlap the material in the first set of trenches (see paragraphs 0111 and 0107-0108).
Since Doany suggests forming the device using known etching and filling methods, it would have been obvious to one of ordinary skill in the art, before the effective filing date of the claimed invention, to modify the Doany method by using the steps taught by Kopp in order to form the Doany coupler.
Regarding claim 15: Modified Doany teachesThe method of claim 14 (as applied above), wherein the overlay material is index matched with the device layer (they are both silicon, see col. 4, lines 54-60).
Regarding claim 16: Modified Doany teaches the method of claim 15, as applied above. In another embodiment, Doany teaches the gratings can be formed wherein the material is amorphous silicon, polysilicon, or dielectric material (see col. 7, lines 9-15). 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. In re Leshin, 125 USPQ 416. It would have therefore been obvious to one of ordinary skill in the art, before the effective filing date of the claimed invention, to use amorphous silicon, polysilicon, or dielectric material for the overlay material, in order to use a known material that can be etched and has suitable properties for the grating and the waveguide layer such as refractive index.
Regarding claim 19: Modified Doany teachesThe method of claim 14 (as applied above), wherein the first set of ridges of the first grating have a non-uniform period (Fig. 6A shows this).
Regarding claim 20: Modified Doany teaches the method of claim 14, as applied above. Doany further teaches that the device layer further includes a waveguide. Since the waveguide is etched to form a grating optically coupled to the waveguide, the etching of the device layer necessarily includes a step of etching the device layer to form a waveguide optically coupled with the first grating.
Allowable Subject Matter
Claims 5-6, 13, and 17-18 are objected to as being dependent upon a rejected base claim, but would be allowable if rewritten in independent form including all of the limitations of the base claim and any intervening claims.
Regarding claim 5: The closest found prior art, Doany, fails to teach or suggest the system of claim 1, wherein the first grating is a blazed grating. While blazed grating are known in the art, it is not understood to be a straightforward/obvious modification to make the union and intersection gratings of Doany into blazed gratings, since this changes the nature of the duty cycle and the union/intersection of the optimized TE and TM gratings. Therefore, claim 5 would be allowable if rewritten in independent form including all of the limitations of the base claim and any intervening claims.
Regarding claim 6: The closest found prior art, Doany, fails to teach or suggest The system of claim 1, wherein: the higher refractive index material is a single-crystal semiconductor; the second set of ridges comprises a non-single-crystal semiconductor; and the first set of trenches are filled with material having a lower refractive index than the single-crystal semiconductor material.
Rather, Doany teaches the two gratings being formed from the same material, which would suggest the higher refractive index material and the material of the second set of ridges comprising the same material, rather than different materials as claimed. Choosing a different material for each grating could introduce an undesired mismatch between the two gratings in the Doany device, and there is no suggestion to do so. Therefore, claim 6 would be allowable if rewritten in independent form including all of the limitations of the base claim and any intervening claims.
Regarding claim 13: While the closest found prior art, Doany, suggests that the coupler of Fig. 6A can be reconfigured as an output coupler and that the light entering the two waveguide layers can be combined into a single waveguide (see col. 6, lines 10-22), Doany fails to teach that light is coupled out of the waveguide using the first grating and the second grating; the first set of ridges and the second set of ridges are configured to cause light from the waveguide to constructively interfere in an upward direction and destructively interfere in a downward direction, thus enhancing a coupling efficiency of light coupled out of the waveguide; and the upward direction is a direction from the first grating toward the second grating, in combination with the other structural limitations positively recited in the claim. Therefore, claim 13 would be allowable if rewritten in independent form including all of the limitations of the base claim and any intervening claims.
Regarding claim 17: The closest found prior art, Doany, fails to teach or suggestimplementing a numerical method to optimize shift and individual widths of ridges of the first set of ridges, such that individual ridges of the first set of ridges have the variation from the average width, in combination with the other method steps positively recited in the claim. Rather, Doany teaches that the individual widths of ridges are a product of the optimization of the TE and TM optimized gratings, which are optimized to have constant widths. Therefore, claim 17 would be allowable if rewritten in independent form including all of the limitations of the base claim and any intervening claims.
Regarding claim 18: At least due to the allowable features of claim 17, claim 18 would also be allowable if rewritten in independent form including all of the limitations of the base claim and any intervening claims.
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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/KIRSTEN D. ENDRESEN/Examiner, Art Unit 2874
/THOMAS A HOLLWEG/Supervisory Patent Examiner, Art Unit 2874
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