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.
Claim Objections
Claims 5, 12, and 14 are objected to because of the following informalities:
Regarding claim 1: “grating coupler comprises” should be “the grating coupler comprises”.
Regarding claim 5: “the extension” should be “an extension”
Regarding claim 12: “preferably from 10 to 100 µm, more preferably from 30 to 100 µm” are not proper limitations because they present a broad limitation followed by a narrow limitation in the claim. Since they are preceded by “preferably” it is understood that they are not required, so it is clear that the claim requires a range of 1 to 100 µm. However, these preferable ranges should be removed from the claim.
Regarding claim 14: Similarly, “preferably germanium telluride, antimony telluride or germanium-antimony-tellurium” should be deleted from claim 14 for the same reason but are clearly not required limitations of the claim since they are preceded by “preferably”.
Appropriate correction is required.
Claim Rejections - 35 USC § 112
The following is a quotation of 35 U.S.C. 112(b):
(b) CONCLUSION.—The specification shall conclude with one or more claims particularly pointing out and distinctly claiming the subject matter which the inventor or a joint inventor regards as the invention.
The following is a quotation of 35 U.S.C. 112 (pre-AIA ), second paragraph:
The specification shall conclude with one or more claims particularly pointing out and distinctly claiming the subject matter which the applicant regards as his invention.
Claims 7 and 11 are rejected under 35 U.S.C. 112(b) or 35 U.S.C. 112 (pre-AIA ), second paragraph, as being indefinite for failing to particularly point out and distinctly claim the subject matter which the inventor or a joint inventor (or for applications subject to pre-AIA 35 U.S.C. 112, the applicant), regards as the invention.
Regarding claim 7: The term “in the vicinity of” in claim 7 is a relative term which renders the claim indefinite. The term “in the vicinity of” is not defined by the claim, the specification does not provide a standard for ascertaining the requisite degree, and one of ordinary skill in the art would not be reasonably apprised of the scope of the invention. Therefore it is unclear what is required by “a tapered shape narrowing in the vicinity of the region in said phase-change material; or a flared shape widening in the vicinity of the region in said phase-change material.”
Regarding claim 11: “the layer” lacks proper antecedent basis. Furthermore, if “the layer” were to be replaced by “a layer”, it is unclear how this layer distinguishes from the “region in said phase-change material” already claimed in claim 1. Therefore, it is unclear, even if the antecedent basis issue were overcome, how this claim further limits claim 1, or even if it attempts to broaden a limitation set by claim 1, which requires the grating coupler to be separated from the region of said phase-change material by a distance between 100 nm and 300 nm. For the purpose of examination, the layer is interpreted as “a layer”.
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 1-2, 4, 8, 11-12, and 14 are rejected under 35 U.S.C. 103 as being unpatentable over Chen et al. (CN 118900624; hereinafter Chen).
Regarding claim 1: Chen disclosesA phase-change material switch (Figs. 1-2) comprising: a region in said phase-change material connecting first and second conduction electrodes of the switch (as shown in Fig. 1, the phase change material spans the area 4, which connects first and second conduction electrodes 3 physically and electrically; therefore, any region thereof is considered to be a region in said phase-change material connecting first and second conduction electrodes of the switch; therefore the region is considered to the portion of the volume of phase change material 4 occupying the bottom nanometer of the phase change material); and a grating coupler (Fig. 1, grating 6) for coupling a laser signal for activating the switch (see 3rd paragraph from bottom of page 3 of the attached translation), located opposite a face of the region in said phase-change material, the grating coupler comprises, vertically in line with the region in said phase-change material, an alternation of first regions in a first material (see Abstract, grating is formed on the surface of the phase change material) having a first optical index (see 4th paragraph, page 3 of attached translation, first material is disclosed to be GeTe, GST or VO2) and of second regions in a second material (the grating is in contact with the passivation layer 5, disclosed to be silicon dioxide or aluminum nitride) having a second optical index strictly lower than the first optical index (the refractive indices of each of these first materials are greater than the refractive indices of each of the second materials).
Regarding the limitation wherein the grating coupler is “separated from the region in said phase-change material by a distance in a range from 100 to 300 nm”: In example 1, Chen discloses that the grating layer is etched to a depth of 50 nm and that the total thickness of the phase-change layer is 150 nm (see 2nd half of page 6 of the attached translation). In this example, the region in said phase-change material identified above is separated from the grating by a distance of 99 nm, falling just outside of the claimed 100 to 300 nm range. In example 2, Chen discloses that the grating layer is etched to a depth of 60 nm and that the total thickness of the phase-change layer is 150 nm (see page 7 of attached translation). In this example, the region in said phase-change material identified above is separated from the grating by a distance of 89 nm, falling outside of the claimed 100 to 300 nm range. However, in both examples, Chen teaches that the total thickness of the phase change layer is not limited to 150 nm. Additionally, the thickness of the phase-change layer is a result effective variable, since it relates to the cross-sectional area connecting the two electrodes, so increasing the area allows more current to flow.
Before the effective filing date of the present invention, a person of ordinary skill in the art would have found it obvious to modify the thickness of the phase change layer of example 1 to be at least 151 nm or to modify the thickness of the phase change layer of example 2 to be at least 161 nm, in order to allow more current to flow between the electrodes in the conductive state of the phase-change layer, 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), 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)), and since such a modification would have involved a mere change in the size of a component and it has been held that a change in size is generally recognized in as being within the level of ordinary skill in the art (In re Rose, 105 USPQ 237 (CCPA 1955)) and that, where the only difference between the prior art and the claims is a recitation of relative dimensions of the claimed device and a device having the claimed relative dimensions would not perform differently than the prior art device, the claimed device is not patentably distinct from the prior art device (In re Gardner v. TEC Systems, Inc., 725 F.2d 1338, 220 USPQ 777 (Fed. Cir. 1984), cert. denied, 469 U.S. 830, 225 USPQ 232 (1984)).
In making the proposed modification, if the phase-change layer of example 1 has a thickness between 151 nm and 351 nm, or if the phase-change layer of example 2 has a thickness between 161 nm and 361 nm, the region identified above would be separated from the grating by a distance falling within the claimed range. If the phase-change layers have an even greater thickness, on the other hand, the region can be suitably redefined such that the distance falls within the claimed range, since the claim does not limit the region to be the bottom nanometer of the phase-change layer, only that it is located within the phase-change material.
Regarding claim 2: Modified Chen teachesThe switch according to claim 1 (as applied above), wherein the grating coupler is configured to irradiate a constant optical power along a direction of propagation of the laser signal for activating the switch (the direction of propagation of the laser signal is perpendicular to the surface of the laser; therefore, the grating coupler is configured to irradiate a constant optical power along a direction of propagation of the laser signal for activating the switch; see also end of page 7 to top of page 8 of attached translation).
Regarding claim 4: Modified Chen teaches the switch according to claim 1, as applied above. Chen further discloses that the first regions are distributed at a constant pitch and have a constant width (see Fig. 2 and 2nd to last paragraph of page 7 of attached translation). Regarding the limitation “wherein the grating coupler is configured to irradiate a decreasing optical power along a direction of propagation of the laser signal for activating the switch”: Chen further teaches that the laser is not limited to the incident angle on the phase change material being vertical (see 3rd paragraph from bottom of page 8). In circumstances where the light is not incident on the surface of the phase change layer vertically, the optical power incident on the grating coupler will decrease along the direction of propagation of the laser signal; therefore, the Chen grating coupler will provide the feature of “wherein the grating coupler is configured to irradiate a decreasing optical power along a direction of propagation of the laser signal for activating the switch”. It would have obvious to one of ordinary skill in the art, before the effective filing date of the claimed invention, to provide laser light at non-vertical incident angles, based on the Chen suggestion, to accommodate design constraints of a particular device, and to better protect the laser from damage due to any back-reflection, for example due to misalignment or the refractive index boundary due to the support substrate.
Regarding claim 8: Modified Chen teachesThe switch according to claim 1 (as applied above), further comprising a support substrate (Fig. 1, passivation layer 5), the grating coupler being interposed between the support substrate and the region in said phase-change material (Fig. 1 shows that the grating layer 6 is interposed between the passivation layer 5 and the phase change layer 4).
Regarding claim 11: Modified Chen teachesThe switch according to claim 1 (as applied above), wherein the grating coupler is separated from the layer in said phase-change material by a distance greater than 100 nm (wherein the layer is considered to also be the layer containing the bottom nanometer of the phase change material, which is the layer containing the region).
Regarding claim 12: Modified Chen teachesThe switch according to claim 1, wherein the region in said phase-change material has a width in a range from 1 to 100 microns, preferably from 10 to 100 microns, more preferably from 30 to 100 microns (see 5th paragraph under Example 1 on page 6 of the provided translation, width is disclosed to be 30 microns; therefore the width of the region in said phase-change material can be mapped to a width in a range from 1 to 100 microns).
Regarding claim 14: Modified Chen teachesThe switch according to claim 1 (as applied above), wherein said phase-change material is: a chalcogenide material, preferably germanium telluride, antimony telluride or germanium-antimony-tellurium; or vanadium dioxide (see 4th paragraph, page 3 of attached translation, first material is disclosed to be germanium telluride or vanadium dioxide).
Claim 13 is rejected under 35 U.S.C. 103 as being unpatentable over Chen et al. (CN 118900624; hereinafter Chen) in view of Schaffner et al. (US 2016/0013549; hereinafter Schaffner).
Modified Chen teaches the switch according to claim 1. Chen fails to teach that the first and second conduction electrodes are part of an antenna element of a transmitarray or a reflectarray cell. However, before the effective filing date of the claimed invention, Shaffner taught that optically actuated switches comprising phase change material between electrodes can form the basis of antennas and be configured for functions such as transmitarrays or reflectarrays (see paragraph 0025). Since it was suggested by Schaffner, it would have been obvious to one of ordinary skill in the art, before the effective filing date of the claimed invention, to use the Chen switch to form part of an antenna element of a transmitarray or a reflectarray cell, in order to effectively direct beams with low loss.
Allowable Subject Matter
Claims 3, 5-6 and 9-10 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 3: The closest found prior art, Chen, fails to teach or suggest: The switch according to claim 2, wherein the first regions are distributed at a constant pitch and have a width decreasing along the direction of propagation of the laser signal for activating the switch.
Claim 2 further requires the grating be “configured to irradiate a constant optical power along a direction of propagation of the laser signal for activating the switch”. This presents a new combination of limitations. Therefore, claim 3 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, Chen and Huang et al. (US 2022/0036170; hereinafter Huang) fails to teach or suggest: The switch according to claim 1, wherein the grating coupler is located in the extension of a waveguide, the waveguide comprising a central region in said first material surrounded by a peripheral region in said second material.
Since the Chen grating is made of the phase-change material, and since the grating is not used to redirect light, but rather to suppress reflections at the refractive index boundary, the Examiner considers that adding a waveguide to the layer made of the phase-change material would rely on improper hindsight reasoning, since the purpose of the grating in such a modified device would be fundamentally different from Chen.
On the other hand, Huang teaches another optically activated switch with a selectively conductive material (see Fig. 6), which redirects vertical light into a horizontally extending waveguide using a grating, then propagates the light through the waveguide and outputs the light using an angled reflective surface to actuate/switch the selectively conductive material. While gratings are known suitable alternatives to angled reflective surfaces for redirecting light, the Examiner does not consider that it would be obvious to one of ordinary skill in the art to modify the Huang device by substituting a grating that is separated from a region of the phase-change material by the distances required by claim 1 for the angled reflective surface.
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: Due at least to the allowable features of claim 5, claim 6 would also be allowable if rewritten in independent form including all of the limitations of the base claim and any intervening claims.
Regarding claim 9: The closest found prior art, Chen, fails to teach or suggest The switch according to claim 8 (as applied above), further comprising a reflective layer interposed between the support substrate and the grating coupler.
Since the purpose of the grating coupler in the Chen device is to prevent reflections, the Examiner does not consider adding a reflective layer interposed between the support substrate and the grating coupler to be an obvious modification, since it would be counterproductive to the stated purpose of providing the grating. Therefore, claim 9 would be allowable if rewritten in independent form including all of the limitations of the base claim and any intervening claims.
Regarding claim 10: Due at least to the allowable features of claim 9, claim 10 would be allowable if rewritten in independent form including all of the limitations of the base claim and any intervening claims.
Due at least to the allowable features of claim 5, claim 7 would be allowable if rewritten to overcome the rejection(s) under 35 U.S.C. 112(b) or 35 U.S.C. 112 (pre-AIA ), 2nd paragraph, set forth in this Office action and to include all of the limitations of the base claim and any intervening claims.
Conclusion
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/KIRSTEN D. ENDRESEN/Examiner, Art Unit 2874
/THOMAS A HOLLWEG/Supervisory Patent Examiner, Art Unit 2874
