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 .
Priority
Receipt is acknowledged of certified copies of papers required by 37 CFR 1.55.
Specification
The abstract of the disclosure is objected to because lines 8-10 recites “a beam intensity adjuster that is arranged between the condenser and the collimation lens and adjusts an intensity of the beams”; However, the recitation of “the beams” seems to refer to the “a plurality of beams” formed by the condenser (“a condenser that forms the laser beam…into parallel light”) and thus suggests that the beam adjuster is positioned downstream of the condenser, which runs contrary to the arrangement further described by “a collimation lens that is arranged between the laser oscillator and the condenser” (i.e., the arrangement being: laser oscillator then collimation lens then beam intensity adjuster then condenser). Examiner suggests the abstract be amended to recite “the laser [[beams]]beam” so as to indicate that the beam intensity adjuster adjusts an intensity of the singular laser beam from the laser oscillator and collimation lens. A corrected abstract of the disclosure is required and must be presented on a separate sheet, apart from any other text. See MPEP § 608.01(b).
The lengthy specification has not been checked to the extent necessary to determine the presence of all possible minor errors. Applicant’s cooperation is requested in correcting any errors of which applicant may become aware in the specification.
Claim Interpretation
Regarding claim 8, which recites “a gauge that measures one of a thickness or a height of the workpiece”
the term “gauge” is used by the claim to mean any instrument or device capable of measuring a thickness or height of a wafer [para. 0019: “No particular limitation is imposed on the type of the gauge 5. For example, the gauge 5 is a contactless thickness gauge, which measures the thickness (or height) of the wafer 10 by applying a measuring laser beam LB0 (see FIGS. 3 and 4) of a predetermined wavelength range from a distal end portion 51 of an extension arm 52, detecting return light reflected by the back surface 10b and the front surface 10a of the wafer 10, and then performing a Fourier transform of a spectral interference waveform based on the return light.”]
Claim Interpretation - 35 USC § 112(f)
The following is a quotation of 35 U.S.C. 112(f):
(f) Element in Claim for a Combination. – An element in a claim for a combination may be expressed as a means or step for performing a specified function without the recital of structure, material, or acts in support thereof, and such claim shall be construed to cover the corresponding structure, material, or acts described in the specification and equivalents thereof.
The claims in this application are given their broadest reasonable interpretation using the plain meaning of the claim language in light of the specification as it would be understood by one of ordinary skill in the art. The broadest reasonable interpretation of a claim element (also commonly referred to as a claim limitation) is limited by the description in the specification when 35 U.S.C. 112(f) is invoked.
As explained in MPEP § 2181, subsection I, claim limitations that meet the following three-prong test will be interpreted under 35 U.S.C. 112(f):
(A) the claim limitation uses the term “means” or “step” or a term used as a substitute for “means” that is a generic placeholder (also called a nonce term or a non-structural term having no specific structural meaning) for performing the claimed function;
(B) the term “means” or “step” or the generic placeholder is modified by functional language, typically, but not always linked by the transition word “for” (e.g., “means for”) or another linking word or phrase, such as “configured to” or “so that”; and
(C) the term “means” or “step” or the generic placeholder is not modified by sufficient structure, material, or acts for performing the claimed function.
Use of the word “means” (or “step”) in a claim with functional language creates a rebuttable presumption that the claim limitation is to be treated in accordance with 35 U.S.C. 112(f). The presumption that the claim limitation is interpreted under 35 U.S.C. 112(f) is rebutted when the claim limitation recites sufficient structure, material, or acts to entirely perform the recited function.
Absence of the word “means” (or “step”) in a claim creates a rebuttable presumption that the claim limitation is not to be treated in accordance with 35 U.S.C. 112(f). The presumption that the claim limitation is not interpreted under 35 U.S.C. 112(f) is rebutted when the claim limitation recites function without reciting sufficient structure, material or acts to entirely perform the recited function.
Claim limitations in this application that use the word “means” (or “step”) are being interpreted under 35 U.S.C. 112(f) except as otherwise indicated in an Office action. Conversely, claim limitations in this application that do not use the word “means” (or “step”) are not being interpreted under 35 U.S.C. 112(f) except as otherwise indicated in an Office action.
The following claim limitations are being interpreted under 35 U.S.C. 112(f):
Regarding claim 1, lines 7-9 recite “a processing feed mechanism that carries out relative processing feed of the chuck table and the processing unit”
In view of:
para. 0016: “Inside the main body section 21, a processing feed mechanism (not illustrated) is disposed to carry out processing feed of the chuck table 32 of the holding unit 3 in the X-axis direction. Operation of the processing feed mechanism moves the cover member 31 along with the chuck table 32 in the X-axis direction”;
para. 0018: “The surface processing machine 1 illustrated in FIG. 2 includes a Z-axis moving mechanism 7, which moves the processing unit 4 along the paired guide rails 221…The Z-axis moving mechanism 7 includes an externally threaded rod 71… Disposed on the upper end portion of the externally threaded rod 71 is a pulse motor 72 as a drive source for rotationally driving the externally threaded rod 71… ”; and
para. 0019: “The above-described laser applying unit 42, processing feed mechanism (not illustrated), gauge 5, Z-axis moving mechanism, and the like are connected to a controller (not illustrated).”;
it seems relative processing feed is used by the claim to mean relative movement during processing, and thus the limitation “processing feed mechanism” is being interpreted as including rails, threaded rods, motors, and equivalents thereof.
Regarding claim 1, lines 13-15 recite “a condenser that forms the laser beam which has been emitted by the laser oscillator, into a plurality of laser beams”
In view of:
para. 0008: “Preferably, the condenser may be a microlens array or a diffractive optical element.”
para. 0021: “The condenser 45 is not limited to the configuration of the above-described microlens array or diffraction optical element alone, and may also be configured by combination with one or more additional condenser lenses, aspherical lenses, or the like.”
the limitation “condenser” is being interpreted as including a microlens array, a diffraction optical element, a condenser lens, or an aspherical lens, and equivalents thereof.
Regarding claim 1, lines 19-21 recite “a beam intensity adjuster that is arranged between the condenser and the collimation lens and adjusts an intensity of the laser beams”
In view of:
para. 0023: “As the beam intensity adjuster 47, a spatial light modulator (reflective type (liquid crystal on silicon (LCOS)) or transmissive type (liquid crystal display (LCD))) or a digital micromirror device (DMD) can be used. The laser beam LB1 passed through the collimation lens 46 is adjusted by the beam intensity adjuster 47, so that the spatial strength distribution of the beams LB2 to be applied from the condenser 45 can be adjusted to a desired spatial strength distribution. In this embodiment, an example with an LCOS, i.e., reflective spatial light modulator, adopted therein is illustrated. However, an LCD, i.e., transmissive spatial light modulator, can also be adopted.”
the limitation “beam intensity adjuster” is being interpreted as a reflective type spatial light modulator, a transmissive type spatial light modulator, or a digital micromirror device, and equivalents thereof.
Regarding claim 1, lines 22-23 recite “a rotating mechanism that rotates the condenser”
In view of:
para. 0022: “As the rotating mechanism 48, a hollow motor is adopted, for example. The hollow motor includes encoders arranged on an outer periphery of a hollow shaft, and is formed in an annular shape.”
the limitation “rotating mechanism” is being interpreted as a hollow motor, and equivalents thereof.
Because these claim limitations are being interpreted under 35 U.S.C. 112(f), they are being interpreted to cover the corresponding structure described in the specification as performing the claimed function, and equivalents thereof.
If applicant does not intend to have these limitations interpreted under 35 U.S.C. 112(f), applicant may: (1) amend the claim limitation(s) to avoid it/them being interpreted under 35 U.S.C. 112(f) (e.g., by reciting sufficient structure to perform the claimed function); or (2) present a sufficient showing that the claim limitations recite sufficient structure to perform the claimed function so as to avoid them being interpreted under 35 U.S.C. 112(f).
Claim Rejections - 35 USC § 112(b)
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.
Claims 1-8 are rejected under 35 U.S.C. 112(b) as being indefinite for failing to particularly point out and distinctly claim the subject matter which the inventor or a joint inventor regards as the invention.
Regarding claim 1, which recites “a beam intensity adjuster that is arranged between the condenser and the collimation lens and adjusts an intensity of the laser beams”
there is insufficient antecedent basis for the limitation “the laser beams”. For the purposes of this office action, and in view of the objection to the abstract (see Specification section above), Examiner will interpret claim 1 as reciting “a beam intensity adjuster that is arranged between the condenser and the collimation lens and adjusts an intensity of the laser [[beams]]beam”
Claims 2-8 are rejected because of dependence on a rejected claim.
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 1-4 and 8 are rejected under 35 U.S.C. 103 as being unpatentable over Eifel (DK 3094444 T3) in view of Tayebati (WO 2018013901 A2).
Regarding claim 1,
Eifel discloses:
A surface processing machine for processing a surface of a workpiece [see fig. 1; p. 21: “Fig. 1 shows an embodiment, by way of example, of a machining device according to the invention for laser machining of a surface 23.”], the surface processing machine comprising:
a processing unit that processes the surface of the workpiece [see fig. 1]; and
a processing feed mechanism that carries out relative processing feed of the chuck table and the processing unit [Eifel discloses a deflection unit that carries out a relative movement between the workpiece and the machining device during processing; p. 19: “the workpiece can be moved relative to the machining device so that a cut gap is produced in the workpiece”; p. 44: “The pattern made of the machining points (laser foci) with a spacing of the spot period is thereby moved by the deflection unit along a scan contour and hence produces a structure.”],
wherein the processing unit includes
a laser oscillator that emits a laser beam [p. 21: “The machining device here has a laser system 1 which emits a collimated laser beam 2.”],
a condenser that forms the laser beam which has been emitted by the laser oscillator, into a plurality of laser beams [p. 25: “The divergence unit 3 can be for example a beam splitter 3… The divergence unit 3 divides the laser beam 29 into a total beam 4 made of partial beams. The distribution of these partial beams is determined by the construction of the divergence unit 3.”],
a collimation [Eifel discloses that the laser beam is collimated prior to being split; p. 8: “Preferably, the divergence unit produces collimated partial beams.”; p. 32: “In summary, the example of Fig. 1 can therefore be produced as follows. A collimated laser beam 2 is emitted from the laser system 1 and subsequently impinges on a rotation unit 28”],
a beam intensity adjuster that is arranged between the condenser and the collimation lens and adjusts an intensity of the laser beams [Eifel discloses that the divergence unit may comprise one or more units, including a spatial light modulator, wherein the intensity distribution is adjusted; p. 25: “The offset laser beam 29 impinges, after the rotation unit 28, on one or more of these divergence units through which it passes or at which it is reflected.”; p. 7: “The divergence unit can preferably be a diffractive optical element with a pattern of micro- and/or nanostructures. The beam splitter can be, in addition, also a dichroic beam splitter, a refractive optical element, such as e.g. a microlens array, or another fixed or dynamic diffraction grating, such as for example a spatial light modulator, a hologram or a grating light valve.”; p. 6: “The divergence unit can however also produce any intensity distribution in the mentioned plane perpendicular to the optical axis.”], and
a rotating mechanism that rotates the condenser [p. 19: “In an advantageous embodiment, the beam splitter can be rotated about the optical axis during machining”; pp. 22-23: “The rotation unit can advantageously be a rotating plane-parallel plate of thickness t which can be actuated by a hollow shaft motor.”].
Although Eifel discloses the relative movement of the workpiece during processing [p. 19], Eifel does not explicitly disclose a chuck table that holds the workpiece.
Although Eifel discloses providing a collimated laser beam 2 emitted from laser system 1, upstream of divergence unit 3, Eifel does not explicitly disclose a collimation lens.
Tayebati, in the same field of endeavor, teaches:
a chuck table (i.e., a mechanical arrangement) that holds the workpiece in order to allow for moving the workpiece [p. 42: “As is well understood in the plotting and scanning art, any requisite relative motion between the output beam and the workpiece may be produced by optical deflection of the beam using a movable mirror, physical movement of the laser using a gantry, lead-screw or other arrangement, and/or a mechanical arrangement for moving the workpiece rather than (or in addition to) the beam.”]; and
the laser oscillator [fig. 3B: laser head 350] may include a collimation lens that collimates a laser beam into parallel light [fig. 3B: collimating lens 355; p. 11, lines 16-17: “The beam shaper may include, consist essentially of, or consist of a collimating lens for collimating a beam received from the beam emitter”; p. 26, lines 7-9: “The laser head 350 includes collimating lens 355 and focusing lens 365 to direct beam 370 onto the surface of the workpiece, just as the laser head 350 depicted in Figure 3B.”].
Therefore, it would have been obvious to one of ordinary skill in the art, before the effective filing date of the invention, to modify the surface processing machine of Eifel, by:
including a chuck table that holds the workpiece since Tayebati discloses this would predictably allow for the requisite relative motion of the workpiece and the output beam; and
substituting the laser system 1 of Eifel with the laser oscillator and collimation lens of Tayebati since Tayebati teaches this would predictably provide a collimated laser beam to the condenser.
Regarding claim 2, Eifel in view of Tayebati discloses the surface processing machine according to claim 1.
Eifel further discloses:
wherein the condenser is a microlens array or a diffractive optical element [p. 7: “The divergence unit can preferably be a diffractive optical element with a pattern of micro- and/or nanostructures.”].
Regarding claim 3, Eifel in view of Tayebati discloses the surface processing machine according to claim 1.
Eifel further discloses:
wherein the beam intensity adjuster is configured to adjust a spatial intensity distribution of the laser beams [p. 5: “The divergence unit can preferably be regarded as a beam splitter. The partial beams can thereby form a continuous intensity distribution in a plane perpendicular to the optical axis, however they can preferably also have an intensity distribution which, for each of the partial beams, has a local maximum of intensity in the mentioned plane perpendicular to the optical axis. In this case, the partial beams respectively can be regarded or be configured as individual laser beams. The partial beams can thereby be superimposed along the optical axis in partial regions in their edge regions with adjacent partial beams or be present completely separately from each other. In the latter case, the intensity distribution in the mentioned plane is discontinuous. The distribution of the partial beams is determined by the construction of the beam splitter.”].
Regarding claim 4, Eifel in view of Tayebati discloses the surface processing machine according to claim 1.
Eifel further discloses:
wherein the processing unit is configured to apply ablation processing to the surface of the workpiece by positioning focal points of the laser beams on the surface through the condenser before processing the surface [p. 12: “The machining device according to the invention has, furthermore, a focusing unit with which the remaining partial beams of the total beam respectively can be focused. Preferably, they can be focused thereby onto the surface to be machined.”].
Regarding claim 8, Eifel in view of Tayebati discloses the surface processing machine according to claim 1.
Eifel as modified by Tayebati, specifically Tayebati further teaches:
wherein the processing unit further includes a gauge that measures one of a thickness or a height of the workpiece held on the chuck table [p. 42, lines 27-32: “ln addition, the laser system may incorporate one or more systems for detecting the thickness of the workpiece and/or heights of features thereon. For example, the laser system may incorporate systems ( or components thereof) for interferometric depth measurement of the workpiece, as detailed in U.S. Patent Application Serial No. 14/676,070, filed on April 1, 2015, the entire disclosure of which is incorporated by reference herein.”].
Therefore, it would have been obvious to one of ordinary skill in the art, before the effective filing date of the invention, to further modify the surface processing machine of Eifel, by including a gauge that measures one of a thickness or a height of the workpiece held on the chuck table, since Tayebati teaches that the thickness may be utilized to optimize the processing of the workpiece [p. 42, line 32 – p. 43, line 1: “Such depth or thickness information may be utilized by the controller to control the output beam shape to optimize the processing ( e.g., cutting or welding) of the workpiece, e.g., in accordance with records in the database corresponding to the type of material being processed.”].
Claim 5 is rejected under 35 U.S.C. 103 as being unpatentable over Eifel (DK 3094444 T3) in view of Tayebati (WO 2018013901 A2) as applied to claim 1 above, and further in view of Kanitz (US 20240316695 A1).
Regarding claim 5, Eifel in view of Tayebati discloses the surface processing machine according to claim 1.
However, Eifel does not disclose:
wherein the processing unit further includes a liquid reservoir receptacle arranged between the condenser and the workpiece and configured to submerge the surface of the workpiece in liquid.
Kanitz, in the same field of endeavor, teaches a liquid reservoir receptacle [fig. 2: process chamber 20] arranged between a focusing unit 18 and a workpiece 22 and configured to submerge the surface of the workpiece in liquid [para. 0079: “FIG. 2 shows an exemplary embodiment of a system for laser processing of a workpiece 22 in liquid according to the present invention.”].
Therefore, it would have been obvious to one of ordinary skill in the art, before the effective filing date of the invention, to modify the surface processing machine of Eifel and Tayebati, by including a liquid reservoir receptacle arranged between the condenser and the workpiece and configured to submerge the surface of the workpiece in liquid since Kanitz teaches that this allows for achieving better cutting and surface quality [para. 0005: “Furthermore, it is known from prior art to perform the laser processing operation in liquid to improve the process described above. This has the particular advantage that the workpiece is cooled directly by the liquid used, which on the one hand avoids or at least reduces undesirable thermal effects and on the other hand prevents ablated material from getting back onto the surface. In particular, this allows better cutting and surface quality to be achieved. For laser processing in liquids, a process chamber can be used, for example, which is provided to receive the workpiece and the liquid.”].
Claims 6 and 7 are rejected under 35 U.S.C. 103 as being unpatentable over Eifel (DK 3094444 T3) in view of Tayebati (WO 2018013901 A2) and Kanitz (US 20240316695 A1) as applied to claim 5 above, and further in view of Jeong (KR 20110091984 A).
Regarding claim 6, Eifel in view of Tayebati and Kanitz discloses the surface processing machine according to claim 5.
Although Kanitz teaches that cavitation bubbles often form during processing [para. 0006: “In addition, cavitation bubbles often form during processing, leading to additional interference effects.”], and is directed towards reducing any corresponding interference effects [para. 0017: “The present invention allows particles and cavitation bubbles created during laser processing of workpieces to be effectively removed from the interior of the processing chamber, thereby significantly reducing any interference effects that may arise during processing.”], Eifel as modified by Tayebati and Kanitz does not explicitly disclose:
wherein the processing unit is configured to apply processing to the surface of the workpiece with plasma generated by application of the laser beams to the liquid in which the surface of the workpiece is submerged in the liquid reservoir receptacle.
Jeong, in the same field of endeavor, teaches that it is known in the art to use water submerging a surface of a workpiece to trap plasma generated by laser processing thereby maximizing pressure in a laser peening process [p. 2: “In addition, in order to prevent the diffusion of plasma generated by applying the laser peening technology and to increase the intensity of the shock wave, water is sprayed on the metal surface to which the laser beam is irradiated, or peening is performed while the specimen is submerged in water. This causes the plasma to be trapped instead of spreading around, as in the air, thus exerting a greater shock wave pressure on the metal surface. As shown in FIG. 1, a general laser pinning system beams a high power laser beam 11 from a light source unit 10 to a specimen 1 to be cured using at least one or more mirrors 21 and 22. Fix the direction of the, focusing the laser beam 11 using the focusing lens 30, increases the energy density of the laser beam (11). At this time, the specimen (1) is located in the chamber 40 filled with water (W), the water (W) is not the plasma generated when the laser beam 11 is irradiated on the specimen (1) without the specimen ( 1) Maximizes the pressure applied to the specimen 1 by focusing on the surface, and the position where pinning is required by moving the path of the laser beam 11 using the XY axis transfer unit 50. Laser peening is performed.”].
Therefore, it would have been obvious to one of ordinary skill in the art, before the effective filing date of the invention, to modify the surface processing machine of Eifel, Tayebati, and Kanitz, by using plasma generated by the application of the laser beams to the liquid in which the surface of the workpiece is submerged in the liquid reservoir receptable, since Jeong teaches that the plasma can be trapped and used to maximize pressure in a laser peening process [p. 2].
Regarding claim 7, Eifel in view of Tayebati and Kanitz discloses the surface processing machine according to claim 5.
Although Kanitz teaches that cavitation bubbles often form during processing [para. 0006: “In addition, cavitation bubbles often form during processing, leading to additional interference effects.”], and is directed towards reducing any corresponding interference effects [para. 0017: “The present invention allows particles and cavitation bubbles created during laser processing of workpieces to be effectively removed from the interior of the processing chamber, thereby significantly reducing any interference effects that may arise during processing.”], Eifel as modified by Tayebati and Kanitz does not explicitly disclose:
wherein the processing unit is configured to apply processing to the surface of the workpiece with cavitation occurred by application of the laser beams to the liquid in which the surface of the workpiece is submerged in the liquid reservoir receptacle.
Jeong, in the same field of endeavor, teaches that it is known in the art to use water submerging a surface of a workpiece to trap plasma generated by laser processing (i.e., the trapped plasma inherently creates a cavitation effect due to expansion/evaporation caused by the plasma) thereby maximizing pressure in a laser peening process [p. 2: “In addition, in order to prevent the diffusion of plasma generated by applying the laser peening technology and to increase the intensity of the shock wave, water is sprayed on the metal surface to which the laser beam is irradiated, or peening is performed while the specimen is submerged in water. This causes the plasma to be trapped instead of spreading around, as in the air, thus exerting a greater shock wave pressure on the metal surface. As shown in FIG. 1, a general laser pinning system beams a high power laser beam 11 from a light source unit 10 to a specimen 1 to be cured using at least one or more mirrors 21 and 22. Fix the direction of the, focusing the laser beam 11 using the focusing lens 30, increases the energy density of the laser beam (11). At this time, the specimen (1) is located in the chamber 40 filled with water (W), the water (W) is not the plasma generated when the laser beam 11 is irradiated on the specimen (1) without the specimen ( 1) Maximizes the pressure applied to the specimen 1 by focusing on the surface, and the position where pinning is required by moving the path of the laser beam 11 using the XY axis transfer unit 50. Laser peening is performed.”].
Therefore, it would have been obvious to one of ordinary skill in the art, before the effective filing date of the invention, to modify the surface processing machine of Eifel, Tayebati, and Kanitz, by using cavitation occurred by the application of the laser beams to the liquid in which the surface of the workpiece is submerged in the liquid reservoir receptable, since Jeong teaches that the plasma and cavitation can be trapped and used to maximize pressure in a laser peening process [p. 2].
Conclusion
Any inquiry concerning this communication or earlier communications from the examiner should be directed to THEODORE J EVANGELISTA whose telephone number is (571)272-6093. The examiner can normally be reached Monday - Friday, 9am - 5pm EST.
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If attempts to reach the examiner by telephone are unsuccessful, the examiner’s supervisor, Edward F Landrum can be reached at (571) 272-5567. The fax phone number for the organization where this application or proceeding is assigned is 571-273-8300.
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/THEODORE J EVANGELISTA/Examiner, Art Unit 3761 /EDWARD F LANDRUM/Supervisory Patent Examiner, Art Unit 3761