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 .
Response to Arguments
Applicant's arguments filed December 29, 2025 have been fully considered but they are not persuasive. Applicant argues that the amendment of Claims 1, 13 and 20 overcome the art of record. Examiner disagrees. Paragraph 0114 of Bek states “Alternatively, the lower or first dielectric layer 535b is arranged to reflect light at the wavelength λ2 of the pump laser 160 used to create a resonator for the pump wavelength, and thus an increased absorption efficiency.” The limitation where the reflecting structure is configured to reflect the pump laser beam is found in Bek therefore the amendment does not overcome the art of record. See below for full rejection
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.
(a)(2) the claimed invention was described in a patent issued under section 151, or in an application for patent published or deemed published under section 122(b), in which the patent or application, as the case may be, names another inventor and was effectively filed before the effective filing date of the claimed invention.
Claims 1-4, 7-8, 13-16, 19-22 are rejected under 35 U.S.C. 102(a)(2) as being anticipated by Bek et al. US 20230275396.
Regarding Claim 1, Bek teaches A laser system (Fig. 7) comprising:
a hybrid membrane vertical-external-cavity surface-emitting laser (Paragraph 0116 “Finally, the individual ones of the semiconductor membrane laser chips are fixed or soldered in step 1060 of FIG. 10 to a submount 700, as shown in FIG. 7 using a soldering process”) comprising:
an external cavity pump laser configured to provide a pump laser beam (Paragraph 0118 “The semiconductor membrane laser is pumped by a pump laser 160 which is able to focus a beam through the lower dielectric layer 535b to the amplifier layer 510 at an angle of 180°.”);
an optically pumped semiconductor active gain structure (Fig. 7, 510 Paragraph 0096 “Here, the lasing medium 510 is pumped by radiation 150 of a pump laser 160”) comprising a top active gain surface and a bottom active gain surface that receives the pumped laser beam (Fig. 7 shows a top side and bottom side of layer 150 where the bottom side receives the pump layer);
a first heat spreading structure (Fig. 7, 520b Paragraph 0096 “A second heat spreader 520b”) comprising a top first heat spreading structure surface and a bottom first heat spreading structure surface, wherein the top first heat spreading structure surface is in thermal contact with the bottom active gain surface (Fig. 7 shows layer 520b has a top surface and a bottom surface and the top of 520b is in direct contact with the bottom of 510 which makes them in thermal contact with each other);
a reflecting structure (Fig.7 535b Paragraph 0114 “On the other hand, the function of the lower or first dielectric layer 535b applied to the lower heat spreader 520b is to enable a high reflection at the wavelength λ1 of the generated laser mode in the amplifier medium 510”) configured to reflect the pump laser beam (Paragraph 0114 “Alternatively, the lower or first dielectric layer 535b is arranged to reflect light at the wavelength λ2 of the pump laser 160 used to create a resonator for the pump wavelength, and thus an increased absorption efficiency”) and comprising a top reflecting structure surface and a bottom reflecting structure surface, wherein the top reflecting structure surface is in contact with the bottom first heat spreading structure; (Fig. 7 shows 535b has a top side and a bottom side and the top of 535b is in contact with the bottom of 520b) and
an external cavity reflector (Fig. 7, 180 Paragraph 0118 “The example shown in FIG. 7 is a linear resonator geometry with a single external mirror 180 coupling the laser beam 175 out of the semiconductor membrane laser.”) that is spaced apart from the optically pumped semiconductor active gain structure forming a free-space region between the external cavity reflector and the optically pumped semiconductor active gain structure (Fig. 7 shows the external cavity reflector is spaced away from active gain structure and there is a free-space region between 180 and 510),
wherein the reflecting structure comprises a semiconductor distributed Bragg reflector, a dielectric stack, a metal, or combinations thereof (Paragraph 0114 “The material used in the dielectric layers 535a,b can be SiO2, Nb2O5, HfO2 TiO2, Al2O3 and Ta2O5, but this is not limiting of the invention.”).
Regarding Claim 2, Bek teaches a second heat spreading structure (Fig. 7, 520a Paragraph 0109 “The two heat spreaders, i.e. the upper heat spreader 520a”) comprising a top second heat spreading structure surface and a bottom second heat spreading structure surface, wherein the bottom second heat spreading structure surface is in thermal contact with the top active gain surface. (Fig. 7 shows 520a has a top surface and a bottom surface and the bottom surface is in contact with the top of the active gain surface so they are in thermal contact.)
Regarding Claim 3, Bek teaches a heat sink structure (Fig. 7, 700, 710) in thermal contact with the first heat spreading structure and the reflecting structure. (Fig. 7 shows the heat sink structure in contact with the first heat spreading structure and the reflecting structure so they are in thermal contact)
Regarding Claim 4, Bek teaches an anti- reflective coating disposed on the top second heat spreading structure or disposed on the top active gain surface. (Fig. 7, 535a Paragraph 0114 “The function of the upper or second dielectric layer 535a deposited on the upper heat spreader 520a may be to enable a high transmission at the wavelength λ1 of the generated laser mode in the amplifier medium 510.”)
Regarding Claim 7, Bek teaches the first heat spreading structure, the second heat spreading structure, or both is composed of SiC, sapphire, or diamond. (Paragraph 0110 “The two heat spreaders 520a and 520b are made, for example of diamond or silicon carbide with good optical qualities to allow passage of the laser radiation.”)
Regarding Claim 8, Bek teaches the semiconductor active gain structure comprises multiple quantum wells. (Paragraph 0101 “Examples of the semiconductor amplifier medium 510 include but are not limited to the following material systems: AlGaInAsP (on GaAs substrate)—e.g. GaInAs quantum wells embedded in GaAs(P) barriers for laser emission in the near infrared spectral range (approx. 850-1200 nm).”)
Regarding Claim 13, Bek teaches A method comprising (Fig. 10):
forming a hybrid membrane vertical-external-cavity surface-emitting laser (Fig. 10, steps 1000-1060) comprising:
forming a first heat spreading structure on an optically pumped semiconductor active gain structure (Fig. 10, 1030 Paragraph 0108 “in step 1030 of FIG. 10 the lower heat spreader 520b is attached to the lower surface 511b of the semiconductor amplifier medium 510 using the same bonding process.”), wherein a top first heat spreading structure surface is in thermal contact with a bottom semiconductor active gain surface; (Fig. 7 shows the top surface is in thermal contact with the bottom of the active gain surface 510)
thermally contacting a heat sink structure with the first heat spreading structure; (Paragraph 0116 “Finally, the individual ones of the semiconductor membrane laser chips are fixed or soldered in step 1060 of FIG. 10 to a submount 700, as shown in FIG. 7 using a soldering process—e.g. using a pre-formed soldering foil 710 or any other metallic fasteners, e.g. in form of a metallic plate.”)
forming a reflecting structure that is configured to reflect a pump laser beam (Paragraph 0114 “Alternatively, the lower or first dielectric layer 535b is arranged to reflect light at the wavelength λ2 of the pump laser 160 used to create a resonator for the pump wavelength, and thus an increased absorption efficiency”) on a bottom first heat spreading structure; (Paragraph 0113 “Subsequently in step 1040 of FIG. 10, the top 525a and the bottom 525b of the wafer layer stack are selectively provided with dielectric layers 535a and 535b by deposition or metal contact layers 530a and 530b by metallization using lithography or shadow masks.”) and
forming an external cavity reflector that is spaced apart from the optically pumped semiconductor active gain structure forming a free-space region between the external cavity reflector and the optically pumped semiconductor active gain structure, (Fig. 7, 180 Paragraph 0118 “The example shown in FIG. 7 is a linear resonator geometry with a single external mirror 180 coupling the laser beam 175 out of the semiconductor membrane laser.”)
wherein the reflecting structure comprises a semiconductor distributed Bragg reflector, a dielectric stack, a metal, or combinations thereof (Paragraph 0114 “The material used in the dielectric layers 535a,b can be SiO2, Nb2O5, HfO2 TiO2, Al2O3 and Ta2O5, but this is not limiting of the invention.”)
Regarding Claim 14, Bek teaches forming a second heat spreading structure on a top semiconductor active gain surface of the semiconductor active gain structure. (Paragraph 0108 “The upper surface of semiconductor amplifier medium 510 is cleaned in step 1010 of FIG. 10 and then the upper heat spreader 520a is applied to the cleansed upper surface 511a of the semiconductor amplifier medium 510 by means of a plasma-activated bonding process to form a direct contact.”)
Regarding Claim 15, Bek teaches the reflecting structure is formed by bonding to the bottom first heat spreading structure. (Paragraph 0113 “Subsequently in step 1040 of FIG. 10, the top 525a and the bottom 525b of the wafer layer stack are selectively provided with dielectric layers 535a and 535b by deposition or metal contact layers 530a and 530b by metallization using lithography or shadow masks)
Regarding Claim 16, Bek teaches comprising forming an anti-reflective coating on a top second heat spreading structure. (Paragraph 0113 “Subsequently in step 1040 of FIG. 10, the top 525a and the bottom 525b of the wafer layer stack are selectively provided with dielectric layers 535a and 535b by deposition or metal contact layers 530a and 530b by metallization using lithography or shadow masks)
Regarding Claim 19, Bek teaches the first heat spreading structure, the second heat spreading structure, or both is composed of SiC, sapphire, or diamond. (Paragraph 0110 “The two heat spreaders 520a and 520b are made, for example of diamond or silicon carbide with good optical qualities to allow passage of the laser radiation.”)
Regarding Claim 20, Bek teaches A method comprising:
lasing from a hybrid membrane vertical-external-cavity surface-emitting laser (Fig. 7, 170) comprising:
directing a pump laser beam from a pump laser to a hybrid membrane vertical external- cavity surface-emitting laser to produce a probe laser beam from the hybrid membrane external- cavity surface-emitting laser (“Paragraph 0118 “The semiconductor membrane laser is pumped by a pump laser 160 which is able to focus a beam through the lower dielectric layer 535b to the amplifier layer 510 at an angle of 180°.”” Paragraph 0096 “Here, the lasing medium 510 is pumped by radiation 150 of a pump laser 160”), the hybrid membrane external-cavity surface-emitting laser comprising a semiconductor active gain structure (Fig. 7, 510 Paragraph 0096 “Here, the lasing medium 510 is pumped by radiation 150 of a pump laser 160”) comprising a top active gain surface and a bottom active gain surface (Fig. 7 shows a top side and bottom side of layer 150); a first heat spreading structure (Fig. 7, 520b Paragraph 0096 “A second heat spreader 520b”) comprising a top first heat spreading structure surface and a bottom first heat spreading structure surface (Fig. 7 shows 520b has a top surface and a bottom surface) and an external cavity reflector (Fig. 7, 180 Paragraph 0118 “The example shown in FIG. 7 is a linear resonator geometry with a single external mirror 180 coupling the laser beam 175 out of the semiconductor membrane laser.”) that is spaced apart from the optically pumped semiconductor active gain structure forming a free-space region between the external cavity reflector and the optically pumped semiconductor active gain structure (Fig. 7 shows the external cavity reflector is spaced away from active gain structure and there is a free-space region between 180 and 510), wherein the top first heat spreading structure surface is in thermal contact with the bottom active gain surface (Fig. 7 shows the top of 520b is in direct contact with the bottom of 510 which makes them in thermal contact with each other); and a reflecting structure (Fig.7 535b Paragraph 0114 “On the other hand, the function of the lower or first dielectric layer 535b applied to the lower heat spreader 520b is to enable a high reflection at the wavelength λ1 of the generated laser mode in the amplifier medium 510”) configured to reflect the pump laser beam (Paragraph 0114 “Alternatively, the lower or first dielectric layer 535b is arranged to reflect light at the wavelength λ2 of the pump laser 160 used to create a resonator for the pump wavelength, and thus an increased absorption efficiency”) and comprising a top reflecting structure surface and a bottom reflecting structure surface, wherein the top reflecting structure surface is in contact with the bottom first heat spreading structure; (Fig. 7 shows 535b has a top side and a bottom side and the top of 535b is in contact with the bottom of 520b),
wherein the reflecting structure comprises a semiconductor distributed Bragg reflector, a dielectric stack, a metal, or combinations thereof (Paragraph 0114 “The material used in the dielectric layers 535a,b can be SiO2, Nb2O5, HfO2 TiO2, Al2O3 and Ta2O5, but this is not limiting of the invention.”).
Regarding Claim 21, Bek teaches the hybrid membrane vertical-external cavity surface-emitting laser comprises a cavity of a multi-pass pumping system. (Paragraph 0114 “Alternatively, the lower or first dielectric layer 535b is arranged to reflect light at the wavelength λ2 of the pump laser 160 used to create a resonator for the pump wavelength, and thus an increased absorption efficiency” The cavity is created by the pump laser light being reflected by 535b multiple times and creating aa multi-pass pumping system.)
Regarding Claim 22, Bek teaches the reflecting structure is configured to reflect the pump laser beam and the laser beam produced by the hybrid membrane vertical-external-cavity surface-emitting laser. (Paragraph 0114 “On the other hand, the function of the lower or first dielectric layer 535b applied to the lower heat spreader 520b is to enable a high reflection at the wavelength λ1 of the generated laser mode in the amplifier medium 510” “Alternatively, the lower or first dielectric layer 535b is arranged to reflect light at the wavelength λ2 of the pump laser 160 used to create a resonator for the pump wavelength, and thus an increased absorption efficiency” The cavity is created by the pump laser light being reflected by 535b multiple times and creating aa multi-pass pumping system.)
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.
The factual inquiries 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 6, 11, 18 are rejected as being unpatentable over 35 U.S.C. 103 over Bek in view of Iakovlev et al. US 20130028279.
Regarding Claim 6, Bek does not teach the first heat spreading structure, the second heat spreading structure, or both is 0.1 to 2.0 mm thick.
However,
Iakovlev teaches the first heat spreading structure, the second heat spreading structure, or both is about 0.1 to about 2.0 mm thick. (Paragraph 0055 “The results show that top diamond layer 3 thickness of 300 µm is the minimal one assuring relatively small impedance, only 1% higher than the structure with the thickest analyzed diamond. Such optimal diamond thickness has been found for three analyzed VECSEL types.” Paragraph 0059 “In the case of Type 2 and Type 3 minimal thermal impedances are assured by 250 µm and 450 µm thick diamond layers, respectively.” )
It would have been obvious for one of ordinary skill in the art before the effective filing date of the claimed invention to have modified the first and second heat spreading structure as taught by Bek by having it be replaced by the diamond heat spreaders as disclosed by Iakovlev. One of ordinary skill in the art would have been motivated to make this modification in order to ensure efficient heat dissipation and thermal performance (Iakovlev Paragraph 0013)
Regarding Claim 11, Bek does not teach the pump laser is configured to produce a pump laser beam incident on the top second heat spreading structure.
However,
Iakovlev teaches a pump laser configured to produce a pump laser beam incident on the top second heat spreading structure. (Iakovlev Fig. 1(b) shows the pump laser beam is produced to be incident on the top of the second heat spreading structure)
It would have been obvious for one of ordinary skill in the art before the effective filing date of the claimed invention to have modified the laser device as taught by Bek by having the laser have the pump laser beam light be incident on the top of the second heat spreading structure as disclosed by Iakovlev. One of ordinary skill in the art would have been motivated to make this modification in order to affect the thermal distribution within the active region (Iakovlev Paragraphs 0061-67)
Regarding Claim 18, Bek does not teach the first heat spreading structure, the second heat spreading structure, or both is 0.1 to 2.0 mm thick.
However,
Iakovlev teaches the first heat spreading structure, the second heat spreading structure, or both is about 0.1 to about 2.0 mm thick. (Paragraph 0055 “The results show that top diamond layer 3 thickness of 300 µm is the minimal one assuring relatively small impedance, only 1% higher than the structure with the thickest analyzed diamond. Such optimal diamond thickness has been found for three analyzed VECSEL types.” Paragraph 0059 “In the case of Type 2 and Type 3 minimal thermal impedances are assured by 250 µm and 450 µm thick diamond layers, respectively.” )
It would have been obvious for one of ordinary skill in the art before the effective filing date of the claimed invention to have modified the first and second heat spreading structure as taught by Bek by having it be replaced by the diamond heat spreaders as disclosed by Iakovlev. One of ordinary skill in the art would have been motivated to make this modification in order to ensure efficient heat dissipation and thermal performance (Iakovlev Paragraph 0013)
Claim 9 is rejected as being unpatentable over 35 U.S.C. 103 over Bek in view of Tabataba-Vakili et al US 9780532.
Regarding claim 9, Bek does not teach the semiconductor active gain structure comprises InGaAs/GaAs.
However,
Tabataba-Vakili teaches the semiconductor active gain structure comprises InGaAs/GaAs. (Col. 8 Lines 15-20 “In certain embodiments, the MQW structure comprises a multilayered structure selected from alternating layers of AlGaN/AlN, InGaN/GaN, InGaAs/GaAs, InGaP/InAlGaP, Zn(S,Cd)Se/Zn(Mg,S)Se, CdSSe/CdS, and combinations thereof.” Underline and bold added for emphasis)
It would have been obvious for one of ordinary skill in the art before the effective filing date of the claimed invention to have modified the active gain structure as taught by Bek by changing the material to InGaAs/GaAs as disclosed by Tabataba-Vakili. One of ordinary skill in the art would have been motivated to make this modification in order to emit a different wavelength of light. (Col. 2, Lines 50-53 “In certain embodiments, an emission wavelength of the laser generated by the method is from 200 nm to 400 nm.”)
Claim 12 is rejected as being unpatentable over 35 U.S.C. 103 over Bek in view of Schad et al. US 20170310069
Regarding claim 12, Bek teaches a pump laser configured to produce a pump laser beam (Fig. 7, 160)
Bek does not teach one or more parabolic mirrors configured to reflect the pump laser and direct the pump laser beam to the semiconductor active gain structure.
However,
Schad teaches one or more parabolic mirrors configured to reflect the pump laser and direct the pump laser beam to the semiconductor active gain structure. (Fig. 1, 11 Paragraphs 0053-54)
It would have been obvious for one of ordinary skill in the art before the effective filing date of the claimed invention to have modified the pump laser beam as taught by Iakovlev by using or more parabolic mirrors to reflect the pump laser beam to the semiconductor active gain structure as disclosed by Hamilton. One of ordinary skill in the art would have been motivated to make this modification in order to focus the pumping light on the gain region (Paragraph 0040 “In some implementations, a concave mirror serves as the focusing device.”)
Conclusion
The prior art made of record and not relied upon is considered pertinent to applicant's disclosure. Luo et al. US 20220209487 Fig. 3 shows the basic MCSEL structure.
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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/STEPHEN SUTTON KOTTER/ Examiner, Art Unit 2828
/MINSUN O HARVEY/ Supervisory Patent Examiner, Art Unit 2828