DETAILED ACTION
Response to Arguments
Applicant's arguments filed 10/21/2025 have been fully considered but they are not persuasive.
Applicant argues (i) the prior art of record does not disclose the plasma based process does not generate coherent x-rays. Applicant's arguments fail to comply with 37 CFR 1.111(b) because they amount to a general allegation that the claims define a patentable invention without specifically pointing out how the language of the claims patentably distinguishes them from the references (e.g. remarks merely state “see above” and does not constitute a complete response). Furthermore, Schmidt discloses how the invention aims at the production of EUV light (see paragraph [0156]), however the wavelengths which are produced and used may range from visible light to soft x-rays.
Applicant further argues that the prior art of record does not disclose (ii) a droplet-shaped converter material, which is capable of generating x-rays by non-linear frequency conversion in response to an irradiation with the driving laser pulses. Examiner disagrees as Schmidt discloses the target is a liquefied noble gas (in particular liquid xenon, see abstract) in the form of a dense fog (20) of microdroplets exposed by a laser beam 24. Further, as discussed above, the target is capable of generating x-rays (see paragraph [0156]).
Applicant argues that Rocca is a capillary discharge of completely different ionization process. However, the art of record is not being relied upon for the capillary discharge. Rocca is cited as reference for driving laser pulses to form non-linear frequency conversion of a target, as specified in the instant application as applicant admitted prior art (see paragraphs [0002-0004]; US Pat. 7,729,403 is the Rocca reference).
Applicant further argues the prior art of record does not disclose (iii) the Helium is in a superfluid state. Examiner disagrees as Schmidt discloses the target is a liquefied noble gas. As stated in the previous office action, while Schmidt specifies liquid xenon, it would be obvious to try a different (one of six) noble gases to expect similar results. Furthermore, a liquified noble gas would exhibit the material properties of a superfluid.
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 1-15 are rejected under 35 U.S.C. 103 as being unpatentable over Schmidt et al. (US PGPub 2004/0129896, hereinafter Schmidt) as evidenced by Rocca et al. (US Pat. 7,729,403, hereinafter Rocca).
Regarding claim 1, Fig. 1 of Schmidt discloses an x-ray laser apparatus being configured to generate coherent x-rays (laser beam 24 interacts with a dense fog of microdroplets, see abstract; producing soft x-rays, see paragraph [0156]) comprising:
an excitation laser device (YAG type for example) arranged to generate driving laser pulses (pulsed laser 22, see paragraph [0096]), and
a converter material source device (tank 2 and nozzle 4) arranged to provide a droplet shaped converter material (liquid xenon 6 formed in a dense fog of droplets 20, see paragraph [0093]), which is capable of generating the coherent x-rays (soft x-rays, see paragraph [0156]), wherein
the excitation laser device (YAG type, for example, see paragraph [0096]) is arranged for a focused irradiation (see paragraph [0096]) of the droplet shaped converter material (liquid xenon 6 formed in a dense fog of droplets 20, see paragraph [0093]).
Schmidt does not disclose the conversion in response to an irradiation with the driving laser pulses is non-linear. However, this is conversion status is an inherent property of noble gas when irradiated by a driving laser as evidenced by applicant admitted prior art of Rocca (see col. 9, lines 4-11).
Schmidt discloses the converter material is liquid xenon 6 (see paragraph [0093]). Schmidt does not disclose the converter material source device is configured to provide superfluid Helium droplets.
MPEP 2143(E) states “To reject a claim based on this rationale, Office personnel must resolve the Graham factual inquiries. Then, Office personnel must articulate the following”:
(1) a finding that at the relevant time, there had been a recognized problem or need in the art, which may include a design need or market pressure to solve a problem (e.g. a method of producing x-rays (see paragraph [0156] of Schmidt) consisting of irradiating a target placed in vacuo by a laser beam (see paragraph [0006] of Schmidt);
(2) a finding that there had been a finite number of identified, predictable potential solutions to the recognized need or problem (abstract of Schmidt identifies a liquid target to be a liquefied noble gas, in particular Xenon);
(3) a finding that one of ordinary skill in the art could have pursued the known potential solutions with a reasonable expectation of success (noble gases being Helium (HE), neon (Ne), Argon (Ar), krypton (Kr), xenon (Xe), radon (Rn), and oganesson (Og) numbering in total: seven); and
(4) whatever additional findings based on the Graham factual inquiries may be necessary, in view of the facts of the case under consideration, to explain a conclusion of obviousness (the claim would have been obvious is that "a person of ordinary skill has good reason to pursue the known options within his or her technical grasp).
Therefore, it would have been obvious to the ordinary artisan before the effective filing date to try another noble gas (one of seven available noble gases) in a liquid form for a superfluid droplet and expect the same material properties of a superfluid.
Regarding claim 2, Schmidt discloses the converter material source device is configured to provide the droplets with at least one of droplet diameter is in the range of 10 nm to 10 μm (see paragraph [0014]) and an atomic density of at least 1023 atoms per cm3 in the superfluid droplet.
Regarding claim 3, Fig. 1 of Schmidt discloses the converter material source device comprises a nozzle device (nozzle 4), a pressure device (pressurized chamber) (see paragraph [0045]), a cooling device (i.e. liquid nitrogen) (see paragraph [0103]), and a reservoir (tank 2) (see paragraph [0086]), wherein
the cooling device is arranged to cool the nozzle device (nozzle 4) to a temperature in a range from 6 to 300 K (-70 degrees Celsius) (see abstract),
the pressure device is configured for applying Xenon to the nozzle device (nozzle 4) with a pressure in a range from 100 mbar to 100 bar (5x105 Pa) (see abstract), and
a nozzle device comprises a nozzle (nozzle 4) which opens into a space with a pressure lower than 10-2 mbar (10-1 Pa) and is configured to generate the superfluid droplets by jet expansion (see paragraph [0045]). A person skilled in the art would recognize the converted units provided by Schmidt fall within the claimed ranges.
Regarding claim 4, Fig. 1 of Schmidt discloses the converter material source device is configured to provide the superfluid droplets as a continuous droplet flow or as a pulsed beam of droplet groups (continuous or pulsed jet) (see paragraph [0040]).
Regarding claim 5, Fig. 1 of Schmidt discloses at least one of the excitation laser device (laser 22) is provided with a positioning device so that the superfluid droplets and the driving laser pulses can be positioned relative to one another (see paragraph [0098]).
Regarding claim 6, Fig. 1 of Schmidt discloses the excitation laser device (laser 22) is configured to generate the driving laser pulses with at least one of a repetition rate in a range from 10 Hz to 100 MHz (>10kHz) (see paragraph [0037]) and a focus intensity in the droplet shaped converter material greater than 1013 W/cm2 (>5x1011 W/cm2) (see paragraph [0096]).
Regarding claim 7, Schmidt discloses the laser pulse (laser 22) is focused with sufficient illumination of the targets for igniting the plasma (see paragraph [0096]). While Schmidt does not explicitly disclose the beam profile having a predominantly flat intensity distribution, However, it would have been obvious to one having ordinary skill in the art at the time the invention was made to shape the laser pulse with the lens and beam source to a sufficient size and power to convert the dense fog of droplets, 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 8, Schmidt discloses a focusing device (collector of EUV light) which is configured to focus the emitted radiation (see paragraph [0134]). While Schmidt teaches about EUV light being emitted, the system disclosed is capable of forming x-rays (see paragraph [0156]) and the same focusing device would reasonably expect to work similarly.
Regarding claim 9, Schmidt discloses a method for generating coherent x-rays (laser beam 24 interacts with a dense fog of microdroplets, see abstract; producing soft x-rays, see paragraph [0156]), comprising the steps of:
generating driving laser pulses (laser 22) with an excitation laser device (see paragraph [0096]),
providing a droplet shaped converter material (liquid xenon dense fog 20) with a converter material source device (tank 2 and nozzle 4) (see paragraph [0093]), and
focused irradiation of the droplet shaped converter material (liquid xenon dense fog 20) with the driving laser pulses (laser 22) (see paragraph [0093]).
Schmidt does not disclose the conversion in response to an irradiation with the driving laser pulses is non-linear. However, this is conversion status is an inherent property of noble gas when irradiated by a driving laser as evidenced by applicant admitted prior art of Rocca (see col. 9, lines 4-11).
Schmidt discloses the converter material is liquid xenon 6 (see paragraph [0093]). Schmidt does not disclose the converter material source device is configured to provide superfluid Helium droplets.
MPEP 2143(E) states “To reject a claim based on this rationale, Office personnel must resolve the Graham factual inquiries. Then, Office personnel must articulate the following”:
(1) a finding that at the relevant time, there had been a recognized problem or need in the art, which may include a design need or market pressure to solve a problem (e.g. a method of producing x-rays (see paragraph [0156] of Schmidt) consisting of irradiating a target placed in vacuo by a laser beam (see paragraph [0006] of Schmidt);
(2) a finding that there had been a finite number of identified, predictable potential solutions to the recognized need or problem (abstract of Schmidt identifies a liquid target to be a liquefied noble gas, in particular Xenon);
(3) a finding that one of ordinary skill in the art could have pursued the known potential solutions with a reasonable expectation of success (noble gases being Helium (HE), neon (Ne), Argon (Ar), krypton (Kr), xenon (Xe), radon (Rn), and oganesson (Og) numbering in total: seven); and
(4) whatever additional findings based on the Graham factual inquiries may be necessary, in view of the facts of the case under consideration, to explain a conclusion of obviousness (the claim would have been obvious is that "a person of ordinary skill has good reason to pursue the known options within his or her technical grasp).
Therefore, it would have been obvious to the ordinary artisan before the effective filing date to try another noble gas (one of seven available noble gases) in a liquid form for a superfluid droplet and expect the same material properties of a superfluid.
Regarding claim 10, Schmidt discloses the converter material source device is configured to provide the droplets with at least one of droplet diameter is in the range of 10 nm to 10 μm (see paragraph [0014]) and an atomic density of at least 1023 atoms per cm3 in the superfluid droplet.
Regarding claim 11, Fig. 1 of Schmidt discloses the excitation laser device (laser 22) is configured to generate the driving laser pulses with at least one of a repetition rate in a range from 10 Hz to 100 MHz (>10kHz) (see paragraph [0037]) and a focus intensity in the droplet shaped converter material greater than 1013 W/cm2 (>5x1011 W/cm2) (see paragraph [0096]).
Regarding claim 12, Schmidt discloses the laser pulse (laser 22) is focused with sufficient illumination of the targets for igniting the plasma (see paragraph [0096]). While Schmidt does not explicitly disclose the beam profile having a predominantly flat intensity distribution, However, it would have been obvious to one having ordinary skill in the art at the time the invention was made to shape the laser pulse with the lens and beam source to a sufficient size and power to convert the dense fog of droplets, 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 13, Schmidt discloses the system is capable of producing x-rays (see paragraph [0156]). While Schmidt does not disclose the spectral range of the photon energy of the produced x-rays, it would have been obvious to one of ordinary skill in the art at the time the invention was made to adjust the output of the emitted radiation to a suitable value for the desired application, since it has been held that where the general conditions of a claim are disclosed in the prior art, discovering the optimum or working ranges involves only routine skill in the art. In re Aller, 105 USPQ 233.
Regarding claim 14, Fig. 1 of Schmidt discloses the excitation laser device (laser 22) and the converter material source device are operated synchronously (see paragraph [0096]).
Regarding claim 15, Schmidt discloses a method for generating coherent x-rays (laser beam 24 interacts with a dense fog of microdroplets, see abstract; producing soft x-rays, see paragraph [0156]), comprising the steps of:
generating driving laser pulses (laser 22) with an excitation laser device (see paragraph [0096]),
providing a droplet shaped converter material (liquid xenon 6 formed in a dense fog of droplets 20) with a converter material source device (tank 2 and nozzle 4) (see paragraph [0093]), and
focused irradiation of the droplet shaped converter material (liquid xenon dense fog 20) with the driving laser pulses (laser 22) (see paragraph [0096]), wherein the x-rays are generated (see paragraph [0156]).
Schmidt does not disclose the conversion in response to an irradiation with the driving laser pulses is non-linear. However, this is conversion status is an inherent property of noble gas when irradiated by a driving laser as evidenced by applicant admitted prior art of Rocca (see col. 9, lines 4-11).
Schmidt discloses the converter material is liquid xenon 6 (see paragraph [0093]). Schmidt does not disclose the converter material source device is configured to provide superfluid Helium droplets.
MPEP 2143(E) states “To reject a claim based on this rationale, Office personnel must resolve the Graham factual inquiries. Then, Office personnel must articulate the following”:
(1) a finding that at the relevant time, there had been a recognized problem or need in the art, which may include a design need or market pressure to solve a problem (e.g. a method of producing x-rays (see paragraph [0156] of Schmidt) consisting of irradiating a target placed in vacuo by a laser beam (see paragraph [0006] of Schmidt);
(2) a finding that there had been a finite number of identified, predictable potential solutions to the recognized need or problem (abstract of Schmidt identifies a liquid target to be a liquefied noble gas, in particular Xenon);
(3) a finding that one of ordinary skill in the art could have pursued the known potential solutions with a reasonable expectation of success (noble gases being Helium (HE), neon (Ne), Argon (Ar), krypton (Kr), xenon (Xe), radon (Rn), and oganesson (Og) numbering in total: seven); and
(4) whatever additional findings based on the Graham factual inquiries may be necessary, in view of the facts of the case under consideration, to explain a conclusion of obviousness (the claim would have been obvious is that "a person of ordinary skill has good reason to pursue the known options within his or her technical grasp).
Therefore, it would have been obvious to the ordinary artisan before the effective filing date to try another noble gas (one of seven available noble gases) in a liquid form for a superfluid droplet and expect the same material properties of a superfluid.
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.
Any inquiry concerning this communication or earlier communications from the examiner should be directed to HANWAY CHANG whose telephone number is (571)270-5766. The examiner can normally be reached on Monday - Friday 7:30 AM - 4:00 PM EST.
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If attempts to reach the examiner by telephone are unsuccessful, the examiner’s supervisor, Robert Kim can be reached on (571)272-2293. The fax phone number for the organization where this application or proceeding is assigned is 571-273-8300.
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Hanway Chang
/HC/Examiner, Art Unit 2881
/MICHAEL J LOGIE/ Primary Examiner, Art Unit 2881