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 .
Continued Examination Under 37 CFR 1.114
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and the fee set forth in 37 CFR 1.17(e) has been timely paid, the finality of the previous Office action has been withdrawn pursuant to 37 CFR 1.114.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 August 27th, 2026, has been entered.
Response to Amendment
In view of the amendment, filed on June 23rd, 2026, the following are withdrawn from the previous office action, mailed on March 30th, 2026.
Rejections of claims 1-3 and 6-20 under 35 U.S.C. 112(a)
Rejections of claims 1-3 and 6-20 under 35 U.S.C. 112(b)
Response to Arguments
Applicant's arguments in view of the amendments filed June 23rd, 2026, concerning the prior art rejections have been fully considered but they are not persuasive.
Applicant argues a PHOSITA would not have modified Mohanty’s precision-focused nanoimprint process to use Watkins’ shrinkage-inducing solvent-absorption curing. Examiner respectfully disagrees. Examiner notes that it has been held that disclosed examples and preferred embodiments do not constitute a teaching away from a broader disclosure or nonpreferred embodiments. See MPEP 2123 (II). While Mohanty discloses “ it is desirable to have a mold (hard mold or soft mold) as precise and accurate as possible” ([0081]) and thermally/UV curing the imprint material ([0077]), it does not prohibit the use of solvent-absorption curing. Mohanty discloses the NIL mold may be formed of PDMS, which in the analogous art Watkins teaches is capable of solvent-absorption curing ([0050]). Furthermore, in response to applicant’s argument that there is no teaching, suggestion, or motivation to combine the references, the examiner recognizes that obviousness may be established by combining or modifying the teachings of the prior art to produce the claimed invention where there is some teaching, suggestion, or motivation to do so found either in the references themselves or in the knowledge generally available to one of ordinary skill in the art. See MPEP 2143.01. The cited prior art references address all of the limitations of the claims and provide a rational and factual motivation for their hypothetical combination, wherein making the combination would allow for the manufacture of large patterned areas in a rapid fashion (Watkins [0011]).
Applicant argues even if Watkins’ solvent-absorption cure were applied to Mohanty, the references do not teach repurposing Mohanty’s sidewall spacers to prevent critical-dimension reduction, absent impermissible hindsight. Examiner respectfully disagrees. In response to Appellant's argument that the examiner's conclusion of obviousness is based upon improper hindsight reasoning, it must be recognized that any judgment on obviousness is in a sense necessarily a reconstruction based upon hindsight reasoning. But so long as it takes into account only knowledge which was within the level of ordinary skill at the time the claimed invention was made, and does not include knowledge gleaned only from the Appellant's disclosure, such a reconstruction is proper. See MPEP 2145 (X). The cited prior art references address all of the limitations of the claims and provide a rational and factual motivation for their hypothetical combination. Furthermore, in response to applicant's argument that Mohanty’s sidewall spacer is disclosed for a different purpose, the fact that the inventor has recognized another advantage which would flow naturally from following the suggestion of the prior art cannot be the basis for patentability when the differences would otherwise be obvious. See MPEP 2145 (II). As the combination of Mohanty and Watkins provides all the limitations of the claimed invention, the resulting combination would also suggest the claimed advantages.
Applicant argues neither Mohanty nor Watkins recognizes lateral solvent flow as the source of critical-dimension loss. Examiner respectfully disagrees. In response to applicant's argument that the references of record do not recognize the source of the problem addressed by the currently pending claims, the fact that the inventor has recognized another advantage which would flow naturally from following the suggestion of the prior art cannot be the basis for patentability when the differences would otherwise be obvious. See MPEP 2145 (II). As the combination of Mohanty and Watkins provides all the limitations of the claimed invention, the resulting combination would also suggest the claimed advantages.
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 1-3, 7, 10-13, 15-18 and 20 are rejected under 35 U.S.C. 103 as being unpatentable over Mohanty et al. (US 20200018875 A1; hereafter Mohanty), in view of Watkins et al. (US 20190243237 A1; hereafter Watkins).
Regarding claim 1, Mohanty discloses a method ([0003]), comprising:
disposing a stamp coating ([0005]; depositing a spacer layer) on a stamp ([0004-0005]; depositing on nanoimprint lithography (NIL) mold), the stamp having an inverse optical device pattern of inverse structures ([0004, 0010]; mold has a plurality of ridges that form a surface-relief grating), the stamp coating disposed on sidewalls (Fig. 11B; [0087]; side wall of each ridge), inverse structure bottom (Fig. 11B; [0087]; exposed areas of substrate), and inverse structure top (Fig. 11B; [0087]; top of ridges) of each of the inverse structures, the inverse optical device pattern having an inverse critical dimension (Fig. 11B; the width between adjacent ridges on structure 1140) between adjacent sidewalls of each of the inverse structures;
etching ([0088]; etching spacer layer) the inverse structure bottom ([0088]; spacer layer on exposed areas of substrate is removed) and inverse structure top ([0088]; spacer layer on top of ridges is removed) with an etch process having an etch direction parallel to the sidewalls such that the stamp coating remains on the sidewalls ([0088]; etching process is such that spacer layer remains on sidewalls of ridges, therefore the etch direction is parallel to the sidewalls) and the stamp coating is removed from the inverse structure top ([0088]; spacer layer on top of ridges is removed) and inverse structure bottom ([0088]; spacer layer on exposed areas of substrate is removed) of each of the inverse structures, the stamp with the stamp coating on the sidewalls having an optical device critical dimension (Fig. 11C; the width between adjacent ridges on structure 1150) between each coated sidewall, the optical device critical dimension to be transferred to optical device structures of an optical device pattern ([0084, 0101]; plurality of ridges on etched mold are used to form nanostructures of surface-relief grating);
imprinting the stamp ([0075-0076]; nanoimprinting with NIL mold) into an imprintable optical device material ([0075-0076]; NIL resist material layer) disposed on an optical device substrate ([0075-0076]; waveguide), the imprintable optical device material has the optical device critical dimension corresponding to the inverse critical dimension of the stamp (see example process in Fig. 9A-9C wherein the pattern is transferred and the imprinted material has the corresponding dimensions of the pattern);
and subjecting the imprintable optical device material to a cure process ([0077]; heat and/or UV light curing), forming a gap ([0075]; the mold may then be separated from the substrate to leave the patterned resist on the substrate) between the inverse structure top and the imprintable optical device material, and transferring the optical device critical dimension to the optical device structures of the optical device pattern formed by the cure process ([0075-0077]; pattern on the mold is transferred).
Mohanty does not explicitly disclose the imprintable optical device material comprises a solvent, the cure process removing the solvent from the imprintable optical device material, the cure process forming a gap between the inverse structure top and the imprintable optical device material while the stamp is imprinted in the imprintable optical device material, and the optical device critical dimension of the optical device structures after the cure process is the same as the optical device critical dimension of the imprintable optical device material while the stamp is imprinted in the imprintable optical device material and before the cure process.
However, Watkins teaches a method of imprint lithography ([0011]) comprising imprinting a stamp ([0009]; textured mold) into an imprintable optical device material ([0009, 0013]; ink for optical applications) comprising a solvent ([0009]; a solvent present in the ink) and subjecting the imprintable optical device material to a cure process ([0008-0010]; the textured mold is operative to absorb the solvent and transfer a texture to the ink, leaving the solid ink), the cure process removing the solvent from the imprintable optical device material ([0009]; the textured mold is operative to absorb the solvent). Watkins further teaches the stamp absorbing the solvent in the cure process would result in a volumetric shrinkage in height and width of the imprintable optical device material during the imprinting process ([0050]). As such, the volumetric shrinkage would result in a gap between the bottom surface of the stamp and the imprintable optical device material.
Mohanty and Watkins are both considered to be analogous to the claimed invention because they are in the field of imprint lithography. Both Mohanty and Watkins disclose that their stamps are formed from PDMS (Mohanty [0076] and Watkins [0050]), similar to the instant application ([0029]). Therefore, it would have been obvious to the person in the ordinary skill in the art before the effective filing date of the invention to modify Mohanty with the teachings of Watkins to provide the claimed limitations. Watkins teaches the volumetric shrinkage results from direct contact between the PDMS stamp and the imprintable optical device material ([0050]) as the solvent is absorbed by the PDMS stamp ([0092]). As the PDMS stamp of Mohanty has the coating with a different surface energy on the sidewalls of the stamp (Fig. 11C), the sidewalls of the PDMS stamp of Mohanty would not make direct contact with the optical device material and not absorb the solvent in the direction of the width analogous to the claimed inverse critical dimension. Accordingly, there would be no volumetric shrinkage in the width direction. The coating is not disposed in the bottom area between the sidewalls of the stamp (Fig. 11C), so the PDMS stamp of Mohanty would still absorb the solvent through the height of the imprinted optical device material and result in volumetric shrinkage in the height and the claimed gap between the inverse structure top and the imprintable optical device material. Use of known technique to improve similar devices (methods, or products) in the same way supports a prima facie obviousness determination. See MPEP 2143 I(C). Doing so would allow for the manufacture of large patterned areas in a rapid fashion (Watkins [0011]).
Regarding claim 2, modified Mohanty discloses the method of claim 1, wherein the optical device substrate comprises silicon (Si) (Mohanty [0073]; silicon), silicon dioxide (SiO2) (Mohanty [0073]; silica), fused silica (Mohanty [0076]; glass), quartz (Mohanty [0076]; quartz), gallium nitride (GaN) (Mohanty [0073]; Gallium nitride), sapphire (Mohanty [0073]; alumina), or combinations thereof.
Regarding claim 3, modified Mohanty discloses the method of claim 1, wherein the imprintable optical device material comprises a nanoimprint resist (Mohanty [0075-0076]; NIL resist material layer) including a solvent (Mohanty [0076]; polymer and monomer mixture) and nanoparticles (Mohanty [0076]; nanoparticles).
Regarding claim 7, modified Mohanty discloses the method of claim 1, wherein the stamp coating is disposed via atomic layer deposition (Mohanty [0087]; spacer layer is deposited via atomic layer deposition).
Regarding claim 10, modified Mohanty discloses a method ([0003]), comprising:
forming a stamp ([[0034]; stamp) from a master ([0034]; stamp maybe formed from a master mold and maybe modified by the same techniques as those used for the master mold), the master comprising a master pattern such that the stamp molded from the master comprises an inverse optical device pattern ([0033-0034]; stamp made from master would form the nanostructures in the optical grating);
disposing a stamp coating ([0005]; depositing a spacer layer) on the stamp ([0004-0005]; depositing on nanoimprint lithography (NIL) mold), the stamp having the inverse optical device pattern of inverse structures ([0004, 0010]; mold has a plurality of ridges that form a surface-relief grating), the stamp coating disposed on sidewalls (Fig. 11B; [0087]; side wall of each ridge), inverse structure bottom (Fig. 11B; [0087]; exposed areas of substrate), and inverse structure top (Fig. 11B; [0087]; top of ridges) of each of the inverse structures, the inverse optical device pattern having an inverse critical dimension (Fig. 11B; the width between adjacent ridges on structure 1140) between adjacent sidewalls of each of the inverse structures;
etching ([0088]; etching spacer layer) the inverse structure bottom ([0088]; spacer layer on exposed areas of substrate is removed) and inverse structure top ([0088]; spacer layer on top of ridges is removed) with an etch process having an etch direction parallel to the sidewalls such that the stamp coating remains on the sidewalls ([0088]; etching process is such that spacer layer remains on sidewalls of ridges, therefore the etch direction is parallel to the sidewalls) and the stamp coating is removed from the inverse structure top ([0088]; spacer layer on top of ridges is removed) and inverse structure bottom ([0088]; spacer layer on exposed areas of substrate is removed) of each of the inverse structures, the stamp with the stamp coating on the sidewalls having an optical device critical dimension (Fig. 11C; the width between adjacent ridges on structure 1150) between each coated sidewall, the optical device critical dimension to be transferred to optical device structures of an optical device pattern ([0084, 0101]; plurality of ridges on etched mold are used to form nanostructures of surface-relief grating);
imprinting the stamp ([0075-0076]; nanoimprinting with NIL mold) into an imprintable optical device material ([0075-0076]; NIL resist material layer) disposed on an optical device substrate ([0075-0076]; waveguide), the imprintable optical device material has the optical device critical dimension corresponding to the inverse critical dimension of the stamp (see example process in Fig. 9A-9C wherein the pattern is transferred and the imprinted material has the corresponding dimensions of the pattern);
and subjecting the imprintable optical device material to a cure process ([0077]; heat and/or UV light curing), forming a gap ([0075]; the mold may then be separated from the substrate to leave the patterned resist on the substrate) between the inverse structure top and the imprintable optical device material, and transferring the optical device critical dimension to the optical device structures of the optical device pattern formed by the cure process ([0075-0077]; pattern on the mold is transferred).
Mohanty does not explicitly disclose the imprintable optical device material comprises a solvent, the cure process removes the solvent from the imprintable optical device material, the cure process forming a gap between the inverse structure top and the imprintable optical device material while the stamp is imprinted in the imprintable optical device material, and the optical device critical dimension of the optical device structures after the cure process is the same as the optical device critical dimension of the imprintable optical device material while the stamp is imprinted in the imprintable optical device material and before the cure process.
However, Watkins teaches a method of imprint lithography ([0011]) comprising imprinting a stamp ([0009]; textured mold) into an imprintable optical device material ([0009, 0013]; ink for optical applications) comprising a solvent ([0009]; a solvent present in the ink) and subjecting the imprintable optical device material to a cure process ([0008-0010]; the textured mold is operative to absorb the solvent and transfer a texture to the ink, leaving the solid ink), the cure process removing the solvent from the imprintable optical device material ([0009]; the textured mold is operative to absorb the solvent). Watkins further teaches the stamp absorbing the solvent in the cure process would result in a volumetric shrinkage in height of the imprintable optical device material during the imprinting process ([0050]). As such, the volumetric shrinkage would result in a gap between the bottom surface of the stamp and the imprintable optical device material.
Mohanty and Watkins are both considered to be analogous to the claimed invention because they are in the field of imprint lithography. Both Mohanty and Watkins disclose that their stamps are formed from PDMS (Mohanty [0076] and Watkins [0050]), similar to the instant application ([0029]). Therefore, it would have been obvious to the person in the ordinary skill in the art before the effective filing date of the invention to modify Mohanty with the teachings of Watkins to provide the claimed limitations. Watkins teaches the volumetric shrinkage results from direct contact between the PDMS stamp and the imprintable optical device material ([0050]) as the solvent is absorbed by the PDMS stamp ([0092]). As the PDMS stamp of Mohanty has the coating with a different surface energy on the sidewalls of the stamp (Fig. 11C), the sidewalls of the PDMS stamp of Mohanty would not make direct contact with the optical device material and not absorb the solvent in the direction of the width analogous to the claimed inverse critical dimension. Accordingly, there would be no volumetric shrinkage in the width direction. The coating is not disposed in the bottom area between the sidewalls of the stamp (Fig. 11C), so the PDMS stamp of Mohanty would still absorb the solvent through the height of the imprinted optical device material and result in volumetric shrinkage in the height and the claimed gap between the inverse structure top and the imprintable optical device material. Use of known technique to improve similar devices (methods, or products) in the same way supports a prima facie obviousness determination. See MPEP 2143 I(C). Doing so would allow for the manufacture of large patterned areas in a rapid fashion (Watkins [0011]).
Regarding claim 11, modified Mohanty discloses the method of claim 10, wherein the optical device substrate comprises silicon (Si) (Mohanty [0073]; silicon), silicon dioxide (SiO2) (Mohanty [0073]; silica), fused silica (Mohanty [0076]; glass), quartz (Mohanty [0076]; quartz), gallium nitride (GaN) (Mohanty [0073]; Gallium nitride), sapphire (Mohanty [0073]; alumina), or combinations thereof.
Regarding claim 12, modified Mohanty discloses the method of claim 10, wherein the imprintable optical device material comprises a nanoimprint resist (Mohanty [0075-0076]; NIL resist material layer) including a solvent (Mohanty [0076]; polymer and monomer mixture) and nanoparticles (Mohanty [0076]; nanoparticles).
Regarding claim 13, modified Mohanty discloses the method of claim 12, wherein the etch process is an angled etch process (Mohanty [0008]; if the ridges are slanted the spacer layer is etched at a slanted angle).
Regarding claim 15, modified Mohanty discloses the method of claim 10, wherein the stamp coating is disposed via atomic layer deposition (Mohanty [0087]; spacer layer is deposited via atomic layer deposition).
Regarding claim 16, Mohanty discloses the method ([0003]), comprising:
disposing a stamp coating ([0005]; depositing a spacer layer) on a stamp ([0004-0005]; depositing on nanoimprint lithography (NIL) mold), wherein:
the stamp comprises an inverse optical device pattern of inverse structures ([0004, 0010]; mold has a plurality of ridges that form a surface-relief grating);
the stamp coating is disposed on sidewalls (Fig. 11B; [0087]; side wall of each ridge), inverse structure bottom (Fig. 11B; [0087]; exposed areas of substrate), and inverse structure top (Fig. 11B; [0087]; top of ridges) of each of the inverse structures;
the inverse optical device pattern comprises an inverse critical dimension (Fig. 11B; the width between adjacent ridges on structure 1140) between adjacent sidewalls of each of the inverse structures;
and the sidewalls have a slant angle ([0084-0085]; ridges on mold may be slanted at any slant angle) relative to a surface normal ([0084-0085]; if the ridges on the mold are angled, then they will be slanted relative to a surface normal of the waveguide imprinted by the mold) of an optical device substrate;
etching ([0088]; etching spacer layer) the inverse structure bottom ([0088]; spacer layer on exposed areas of substrate is removed) and inverse structure top ([0088]; spacer layer on top of ridges is removed) with an etch process having an etch direction parallel to the sidewalls such that the stamp coating remains on the sidewalls ([0088]; etching process is such that spacer layer remains on sidewalls of ridges, therefore the etch direction is parallel to the sidewalls) and the stamp coating is removed from the inverse structure top ([0088]; spacer layer on top of ridges is removed) and inverse structure bottom ([0088]; spacer layer on exposed areas of substrate is removed) of each of the inverse structures, the stamp with the stamp coating on the sidewalls having an optical device critical dimension (Fig. 11C; the width between adjacent ridges on structure 1150) between each coated sidewall, the optical device critical dimension to be transferred to optical device structures of an optical device pattern ([0084, 0101]; plurality of ridges on etched mold are used to form nanostructures of surface-relief grating);
imprinting the stamp ([0075-0076]; nanoimprinting with NIL mold) into an imprintable optical device material ([0075-0076]; NIL resist material layer) disposed on the optical device substrate ([0075-0076]; waveguide), the imprintable optical device material has the optical device critical dimension corresponding to the inverse critical dimension of the stamp (see example process in Fig. 9A-9C wherein the pattern is transferred and the imprinted material has the corresponding dimensions of the pattern);
and subjecting the imprintable optical device material to a cure process ([0077]; heat and/or UV light curing), forming a gap ([0075]; the mold may then be separated from the substrate to leave the patterned resist on the substrate) between the inverse structure top and the imprintable optical device material, and transferring the optical device critical dimension to the optical device structures of the optical device pattern formed by the cure process ([0075-0077]; pattern on the mold is transferred).
Mohanty does not explicitly disclose the imprintable optical device material comprises a solvent, the cure process removes the solvent from the imprintable optical device material, the cure process forming a gap between the inverse structure top and the imprintable optical device material while the stamp is imprinted in the imprintable optical device material and the optical device critical dimension of the optical device structures after the cure process is the same as the optical device critical dimension of the imprintable optical device material while the stamp is imprinted in the imprintable optical device material and before the cure process.
However, Watkins teaches a method of imprint lithography ([0011]) comprising imprinting a stamp ([0009]; textured mold) into an imprintable optical device material ([0009, 0013]; ink for optical applications) comprising a solvent ([0009]; a solvent present in the ink) and subjecting the imprintable optical device material to a cure process ([0008-0010]; the textured mold is operative to absorb the solvent and transfer a texture to the ink, leaving the solid ink), the cure process removing the solvent from the imprintable optical device material ([0009]; the textured mold is operative to absorb the solvent). Watkins further teaches the stamp absorbing the solvent in the cure process would result in a volumetric shrinkage in height of the imprintable optical device material during the imprinting process ([0050]). As such, the volumetric shrinkage would result in a gap between the bottom surface of the stamp and the imprintable optical device material.
Mohanty and Watkins are both considered to be analogous to the claimed invention because they are in the field of imprint lithography. Both Mohanty and Watkins disclose that their stamps are formed from PDMS (Mohanty [0076] and Watkins [0050]), similar to the instant application ([0029]). Therefore, it would have been obvious to the person in the ordinary skill in the art before the effective filing date of the invention to modify Mohanty with the teachings of Watkins to provide the claimed limitations. Watkins teaches the volumetric shrinkage results from direct contact between the PDMS stamp and the imprintable optical device material ([0050]) as the solvent is absorbed by the PDMS stamp ([0092]). As the PDMS stamp of Mohanty has the coating with a different surface energy on the sidewalls of the stamp (Fig. 11C), the sidewalls of the PDMS stamp of Mohanty would not make direct contact with the optical device material and not absorb the solvent in the direction of the width analogous to the claimed inverse critical dimension. Accordingly, there would be no volumetric shrinkage in the width direction. The coating is not disposed in the bottom area between the sidewalls of the stamp (Fig. 11C), so the PDMS stamp of Mohanty would still absorb the solvent through the height of the imprinted optical device material and result in volumetric shrinkage in the height and the claimed gap between the inverse structure top and the imprintable optical device material. Use of known technique to improve similar devices (methods, or products) in the same way supports a prima facie obviousness determination. See MPEP 2143 I(C). Doing so would allow for the manufacture of large patterned areas in a rapid fashion (Watkins [0011]).
Regarding claim 17, modified Mohanty discloses the method of claim 16, wherein the imprintable optical device material comprises a nanoimprint resist (Mohanty [0075-0076]; NIL resist material layer) including a solvent (Mohanty [0076]; polymer and monomer mixture) and nanoparticles (Mohanty [0076]; nanoparticles).
Regarding claim 18, modified Mohanty discloses the method of claim 16, wherein the etch process is an angled etch process (Mohanty [0008]; if the ridges are slanted the spacer layer is etched at a slanted angle).
Regarding claim 20, modified Mohanty discloses the method of claim 16, wherein the stamp coating is disposed via atomic layer deposition (Mohanty [0087]; spacer layer is deposited via atomic layer deposition).
Claims 6, 8, 14 and 19 are rejected under 35 U.S.C. 103 as being unpatentable over Mohanty et al. (US 20200018875 A1; hereafter Mohanty), in view of Watkins et al. (US 20190243237 A1; hereafter Watkins) as applied to claims 1, 10 and 16, and further in view of Gao et al. (US 20140234466 A1; hereafter Gao).
Regarding claim 6, modified Mohanty discloses the method of claim 1.
Modified Mohanty does not explicitly disclose the stamp coating comprises amorphous silicon, polysilicon, aluminum oxide (Al203), silicon nitride (Si3N4), silicon dioxide (SiO2), graphene, or combinations thereof.
However, Gao teaches depositing a stamp coating ([0030]; depositing a layer of spacer material) on a stamp ([Fig. 4C; imprint mold 200), wherein the stamp coating comprises amorphous silicon ([0030]; Si), polysilicon ([0030]; Si), aluminum oxide (Al203) ([0030]; aluminum oxide) or silicon nitride (Si3N4) ([0030]; silicon nitride).
Mohanty and Gao are both considered to be analogous to the claimed invention because they are in the field of imprint lithography. Therefore, it would have been obvious to the person in the ordinary skill in the art before the effective filing date of the invention to modify modified Mohanty with the teachings of Gao to provide the stamp coating comprises amorphous silicon ([0030]; Si), polysilicon ([0030]; Si), aluminum oxide (Al203) ([0030]; aluminum oxide) or silicon nitride (Si3N4) ([0030]; silicon nitride). Stamp coatings comprising the claimed materials are well-known in the art and it would have been obvious for one of ordinary skill in the art to select one of the materials for the stamp coating such that the stamp coating can be easily etched using well known etching processes in order to provide stamps capable of forming structures with the desired critical dimension.
Regarding claim 8, modified Mohanty discloses the method of claim 1.
Modified Mohanty does not explicitly disclose each of the optical device structures have a critical dimension less than 1 micrometer.
However, Gao teaches imprinting ([0036]) with an imprint mold ([0036]; imprint mold 200), wherein the imprinting forms structures (Fig. 5A; [0036]; stripes 510) having a critical dimension less than 1 micrometer (Fig. 4E-5A; [0029-0030, 0036]; width of strips 302 is 13nm and the width of the gaps between the strips 302 is the same 13nm or less, therefore the formed stripes 510 have a width of approx. 13nm).
Mohanty and Gao are both considered to be analogous to the claimed invention because they are in the field of imprint lithography. Therefore, it would have been obvious to the person in the ordinary skill in the art before the effective filing date of the invention to modify modified Mohanty with the teachings of Gao to provide each of the optical device structures have a critical dimension less than 1 micrometer. Doing so would allow for the manufacture of optical devices with smaller-sized features as desired.
Regarding claim 14, modified Mohanty discloses the method of claim 10.
Modified Mohanty does not explicitly disclose the stamp coating comprises amorphous silicon, polysilicon, aluminum oxide (Al203), silicon nitride (Si3N4), silicon dioxide (SiO2), graphene, or combinations thereof.
However, Gao teaches depositing a stamp coating ([0030]; depositing a layer of spacer material) on a stamp ([Fig. 4C; imprint mold 200), wherein the stamp coating comprises amorphous silicon ([0030]; Si), polysilicon ([0030]; Si), aluminum oxide (Al203) ([0030]; aluminum oxide) or silicon nitride (Si3N4) ([0030]; silicon nitride).
Mohanty and Gao are both considered to be analogous to the claimed invention because they are in the field of imprint lithography. Therefore, it would have been obvious to the person in the ordinary skill in the art before the effective filing date of the invention to modify modified Mohanty with the teachings of Gao to provide the stamp coating comprises amorphous silicon ([0030]; Si), polysilicon ([0030]; Si), aluminum oxide (Al203) ([0030]; aluminum oxide) or silicon nitride (Si3N4) ([0030]; silicon nitride). Stamp coatings comprising the claimed materials are well known in the art and it would have been obvious for one of ordinary skill in the art to select one of the materials for the stamp coating such that the stamp coating can be easily etched using well known etching processes in order to provide stamps capable of forming structures with the desired critical dimension.
Regarding claim 19, modified Mohanty discloses the method of claim 16.
Modified Mohanty does not explicitly disclose the stamp coating comprises amorphous silicon, polysilicon, aluminum oxide (Al203), silicon nitride (Si3N4), silicon dioxide (SiO2), graphene, or combinations thereof.
However, Gao teaches depositing a stamp coating ([0030]; depositing a layer of spacer material) on a stamp ([Fig. 4C; imprint mold 200), wherein the stamp coating comprises amorphous silicon ([0030]; Si), polysilicon ([0030]; Si), aluminum oxide (Al203) ([0030]; aluminum oxide) or silicon nitride (Si3N4) ([0030]; silicon nitride).
Mohanty and Gao are both considered to be analogous to the claimed invention because they are in the field of imprint lithography. Therefore, it would have been obvious to the person in the ordinary skill in the art before the effective filing date of the invention to modify modified Mohanty with the teachings of Gao to provide the stamp coating comprises amorphous silicon ([0030]; Si), polysilicon ([0030]; Si), aluminum oxide (Al203) ([0030]; aluminum oxide) or silicon nitride (Si3N4) ([0030]; silicon nitride). Stamp coatings comprising the claimed materials are well known in the art and it would have been obvious for one of ordinary skill in the art to select one of the materials for the stamp coating such that the stamp coating can be easily etched using well known etching processes in order to provide stamps capable of forming structures with the desired critical dimension.
Claim 9 is rejected under 35 U.S.C. 103 as being unpatentable over Mohanty et al. (US 20200018875 A1; hereafter Mohanty), in view of Watkins et al. (US 20190243237 A1; hereafter Watkins) as applied to claim 1, and further in view of Calafiore (US 20200409151 A1).
Regarding claim 9, modified Mohanty discloses the method of claim 1.
Modified Mohanty does not explicitly disclose each of the optical device structures have a refractive index between 1.35 and 4.0.
However, Calafiore teaches optical device structures ([0158]; refractive grating) formed by nanoimprint lithography ([0157]) comprising a refractive index between 1.35 and 4.0 ([0158]; refractive index of grating ridges may be about 1.6).
Mohanty and Calafiore are both considered to be analogous to the claimed invention because they are in the field of imprint lithography. Therefore, it would have been obvious to the person in the ordinary skill in the art before the effective filing date of the invention to modify modified Mohanty with the teachings of Calafiore to provide each of the optical device structures have a refractive index between 1.35 and 4.0. Imprint lithography to form refractive index optical devices is well known in the art and therefore it would have been obvious to make the combination in order to provide optical devices with higher refractive indexes (Calafiore [0039]).
Conclusion
Any inquiry concerning this communication or earlier communications from the examiner should be directed to Vipul Malik whose telephone number is (571)272-0976. The examiner can normally be reached M-F.
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/VIPUL MALIK/Examiner, Art Unit 1754
/SEYED MASOUD MALEKZADEH/Primary Examiner, Art Unit 1754
