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 .
Status
In response to the amendment filed on 11/11/2025, claims 1, 3, 10, 14, 15, and 17 have been amended. Claims 9 and 13 were previously cancelled. Claims 1-8, 10-12, and 14-22 are pending and under examination.
Information Disclosure Statement
The information disclosure statement (IDS) submitted on 02/06/2026 is in compliance with the provisions of 37 CFR 1.97. Accordingly, the information disclosure statement is being considered by the examiner.
Drawings
The drawings are objected to under 37 CFR 1.83(a). The drawings must show every feature of the invention specified in the claims. Therefore, the second microchannels extending from the first top grooves to the first bottom pad and being misaligned with the first bottom grooves as recited in claim 10 must be shown or the feature(s) canceled from the claim(s). No new matter should be entered.
Corrected drawing sheets in compliance with 37 CFR 1.121(d) are required in reply to the Office action to avoid abandonment of the application. Any amended replacement drawing sheet should include all of the figures appearing on the immediate prior version of the sheet, even if only one figure is being amended. The figure or figure number of an amended drawing should not be labeled as “amended.” If a drawing figure is to be canceled, the appropriate figure must be removed from the replacement sheet, and where necessary, the remaining figures must be renumbered and appropriate changes made to the brief description of the several views of the drawings for consistency. Additional replacement sheets may be necessary to show the renumbering of the remaining figures. Each drawing sheet submitted after the filing date of an application must be labeled in the top margin as either “Replacement Sheet” or “New Sheet” pursuant to 37 CFR 1.121(d). If the changes are not accepted by the examiner, the applicant will be notified and informed of any required corrective action in the next Office action. The objection to the drawings will not be held in abeyance.
Claim Objections
Claims 2 and 3 are objected to because of the following informalities:
Claim 3 has been amended and it recites the same claim limitations with claim 2. Examiner advises canceling either claim 2 or claim 3.
Appropriate correction is required.
Claim Rejections - 35 USC § 112
The following is a quotation of the first paragraph of 35 U.S.C. 112(a):
(a) IN GENERAL.—The specification shall contain a written description of the invention, and of the manner and process of making and using it, in such full, clear, concise, and exact terms as to enable any person skilled in the art to which it pertains, or with which it is most nearly connected, to make and use the same, and shall set forth the best mode contemplated by the inventor or joint inventor of carrying out the invention.
Claim 15 is rejected under 35 U.S.C. 112(a) or 35 U.S.C. 112 (pre-AIA ), first paragraph, as failing to comply with the written description requirement. The claim(s) contains subject matter which was not described in the specification in such a way as to reasonably convey to one skilled in the relevant art that the inventor or a joint inventor, or for applications subject to pre-AIA 35 U.S.C. 112, the inventor(s), at the time the application was filed, had possession of the claimed invention.
Claim 15 recites, inter alia, “wherein polishing the wafer with the first polishing pad removes first particles from the wafer, and wherein the first particles have a higher specific gravity than the slurry” As set forth above, these limitations are not supported in the originally filed specification. Specification states, in ¶ 0024, “the removed particles 150 – especially those having a higher specific gravity than the slurry 120 – will have a tendency to be drawn closer to the polishing pad 140 than to the wafer 115 simply due to gravity”. The specification does not disclose the first polishing pad removes [only] first particles, and some of the particles have the higher specific gravity than the slurry. Therefore, the recitation is considered to be New Matter.
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 1-8, 15-20, and 22 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.
In claim 1, lines 4-8, the phrase “the first microchannels having a conical shape, …, a smallest circular cross-section of the conical shape being at an upper surface of the first sub pad” renders claim vague and indefinite. The first microchannels extend through a thickness of the first top pad as defined in lines 2-4 of claim 1. The first sub pad does not comprise the first microchannels, therefore, there cannot be the circular cross-section of the first microchannels at the upper surface of the first sub pad. Examiner brought the similar 112(b) rejection in the previous non-final office action dated on 08/11/2025, but the amendment was made incorrectly. For examination purposes the examiner has interpreted the smallest circular cross-section of the conical shape is at the bottom surface of the first top pad.
Claims 2-8 inherit the above deficiency by nature of their dependency.
In claim 15, lines 17-19, the phrase “wherein polishing the wafer with the first polishing pad removes first particles from the wafer, and wherein the first particles have a higher specific gravity than the slurry” renders claim vague and indefinite. Does it mean a mechanical polishing pad selectively remove only the first particles wherein the first particles have higher specific gravity than the slurry among many other particles of a wafer? Specification of the instant application presents the removed particles have mixed specific gravities and some of them have higher specific gravity than the slurry. Therefore, it is not clear how the polishing pad removes only the first particles having higher specific gravity than the slurry. Additionally, specific gravity, which is a relative density of particles with respect to density of water, is simply a comparison of density or weight. Density of solid particle must be higher than density of slurry which is a mixture of solid particles and liquid. Moreover, claim does not define what the first particles are or what the slurry is made of. The removed particles can be any particle. The slurry may comprise all liquid without any solid. Therefore, for examination purpose the examiner has interpreted the first polishing pad removes particles from the wafer. The removed particles are designated as the first particles and all removed particles have the higher specific gravity than the slurry.
Claims 16-20 and 22 inherit the above deficiency by nature of their dependency.
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 1-5 are rejected under 35 U.S.C. 103 as being unpatentable over Kirchner (US 6,692,338, cited on 07/26/2023 IDS), in view of Mukai et al. (US 2017/0312886, hereinafter Mukai), Uzoh et al. (US 6,413,388, cited on 07/26/2023 IDS, hereinafter Uzoh), and Bajaj et al. (CN 107078048A, hereinafter Bajaj).
Regarding claim 1, Kirchner disclose a method, comprising:
attaching a first top pad to a first sub pad to form a first polishing pad (fig. 3A and col. 5:1-21, a pad 300 [corresponds to the recited top pad] is attached to a pad backing 304 [corresponds to the recited sub pad]. Therefore, there is a method of attaching the top pad to the sub pad to form a polishing pad), the first top pad comprising a first pattern of first top grooves (Kirchner, figs. 3A and 3B, the first top grooves 356 have a first pattern) and first microchannels (col. 6:13-20, slurry drain holes 354; note the width value of 0.2 mm) extending through a thickness of the first top pad (Kirchner, col. 5:51-52 and 6:22-29, slurry drain holes 354 [correspond to the recited microchannels] are aligned with pad bottom drain grooves 362; see also similarly configured drain holes 308 in Figure 3A. Thus, the slurry drain holes extend through a thickness of the top pad), the first sub pad comprising first bottom grooves (col. 6:22-29 and fig. 3A, a pad backing 304 [corresponds to the recited first sub pad] is disclosed as being used with fig. 3B’s pad and it faces the top pad. The pad backing 304 is disclosed as having drain grooves 325 [correspond to the first bottom grooves] in the backing’s top surface adjacent the other pad);
attaching the first polishing pad to a platen (see fig. 2A, polishing pad 220 is attached to a platen 208. Therefore, there is a step of attaching the polishing pad to the platen);
dispensing a first slurry over the first polishing pad (fig. 2A and col. 2:55-59, slurry is applied to the pad 220);
rotating the first polishing pad (col. 3:10-12, the pad rotates during polishing).
Although Kirchner does not disclose explicitly the method of detaching the first polishing pad from the platen and detaching the first top pad from the first sub pad, Kirchner teaches the method of attaching the first polishing pad to the platen and attaching the first top pad to the first sub pad as discussed above. Therefore, it would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to have modified the method of Kirchner to detach the first polishing pad from the platen and detach the first top pad from the fist sub pad in order to perform service or replacement of the top pad.
Kirchner discloses that a similar pad 300 can be bonded to its corresponding pad backing 304 by a suitable adhesive and it is known in the art to replace pads when worn or broken. Thus, the second top pad being attachable to the first sub pad to form a second polishing pad.
Note that the second pad's features are identical to the first pad's features. In an analogous art, Mukai at [0054] discloses a polishing pad that uses a tacky, pressure sensitive adhesive for adhering the abrasive/polishing layer so that the abrasive layer can be detached and replaced with another abrasive layer. Then the second polishing pad is attached to a platen as shown in Kirchner fig. 2A for the first polishing pad.
It would have been obvious to a person of ordinary skill in the art before the effective filing date of the invention to have modified Kirchner’s adhesive to specifically be a tacky, pressure sensitive adhesive for adhering the abrasive/polishing layer in view of the teachings in Mukai so that the abrasive layer can be detached and replaced with another abrasive layer. Due to this modification, the adhesive between the pad and backing of Kirchner is now specific to a detachable adhesive such that the first pad is interchangeably attached to the sub pad to form a first polishing pad. Further, the modification results in the ability to replace the first top pad, when worn or broken, with another/new pad such that this new pad is a second top pad of the same character and nature (i.e., one with top surface grooves) of the first top pad. Further, as stated in MPEP 2144.04(VI)(B), it has been held that mere duplication of parts has no patentable significance unless a new and unexpected result is produced (of which Applicant’s specification is devoid), and thus it would have been obvious further in view of Mukai’s teachings to provide an identical second top pad predictably for replacement purposes when the first top pad has become worn or broken without having to replace the entire pad construct (including the sub pad/backing).
However, Kirchner as modified by Mukai does not disclose the lowest depth of the first top grooves is greater than a lowest depth of the first bottom grooves; and a lowest depth of the second top grooves is less than the lowest depth of the first bottom grooves.
Kirchner as modified by Mukai teaches the first top grooves, the second top grooves, and the first bottom grooves having depths except for the different groove depths (Kirchner, col. 6:13-20, drain grooves may have a depth of 0.8 mm). On the other hand, specification of the instant application is silent regarding reason why the depth of the first top grooves needs to be greater than the depth of the first bottom grooves and the depth of the second top grooves needs to be less than the depth of the first bottom grooves. Specification only states that the top grooves and the sub grooves may have the same or different depths (¶ 0037).
Therefore, it would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to have modified the first and second top grooves of Kirchner as modified by Mukai to make the depth of the first top grooves to be greater than the depth of the first bottom grooves and the depth of the second top grooves to be less than the depth of the first bottom grooves in order to achieve different slurry drain rates for quality and effective CMP process. Such a modification would have involved a mere change in the size of a component. A change in size is generally recognized as being within the level of ordinary skill in the art. See MPEP 2144.04(IV)(A).
Kirchner as modified by Mukai still does not disclose the first microchannels being between a lowest depth of the first top grooves of the first top pad and a bottom surface of the first sub pad.
Uzoh teaches, in an analogous CMP field of endeavor, the first microchannels being between a lowest depth of the first top grooves of the first top pad and a bottom surface of the first sub pad (fig. 7a and col. 15:12-14, a polishing pad has grooves 770 [correspond to the recited top grooves] on a surface of the polishing pad and channels 772 [correspond to the recited microchannels] are located at a lowest depth of the grooves 770. The channels 772 extend to a bottom surface of the polishing pad. As discussed in 112(b) rejection above, the first microchannels extend to the bottom surface of the first top pad, instead of the first sub pad).
It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to have modified the microchannels of Kirchner as modified by Mukai to provide the microchannels at the lowest depth of the top grooves as taught by Uzoh in order to improve the control of slurry flow on the pad surface by optimizing fluid dynamics (Uzoh, col. 15:12-14).
Kirchner as modified by Mukai and Uzoh does not disclose the first microchannels having a conical shape.
Bajaj teaches, in an analogous CMP field of endeavor, the first microchannels having a conical shape (fig. 22 and Bajaj English translation, p. 30:22-33, a polishing pad comprises holes 2232 [correspond to the recited microchannels]. The holes 2232 have geometrical shape such as a cone or hollow truncated cone).
It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to have modified the microchannels of Kirchner as modified by Mukai and Uzoh to provide its shape to be the conical shape as taught by Bajaj in order to improve effectiveness of polishing operation.
Kirchner as modified by Mukai, Uzoh, and Bajaj still does not disclose a largest circular cross-section of the conical shape being at a top of the first microchannel and a smallest circular cross-section of the conical shape at a bottom of the first microchannel (see 112(b) rejection regarding the location of the smallest circular cross-section of the conical shape).
Bajaj does not disclose whether the hollow truncated cone is upside down. However, it would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to have modified the cone-shaped microchannels of the polishing pad to have the largest cross-section at the top and the smallest cross-section at the bottom of the microchannel so that the holes/microchannels can receive slurry and other fluid at the top of the polishing pad and drain them to below of the polishing pad effectively.
Regarding claims 2 and 3, Kirchner as modified by Mukai, Uzoh, and Bajaj teaches the method as in the rejection of claim 1, but does not disclose explicitly a width of each of the first top grooves is greater than a width of each of the second top grooves.
As discussed in claim 1 above, however, Kirchner as modified by Mukai, Uzoh, and Bajaj teaches the first top grooves and the second top grooves having widths except for the different groove widths (Kirchner, col. 6:13-20, drain grooves may have a width of 0.8 mm). On the other hand, specification of the instant application is silent regarding reason why the width of the first top grooves needs to be greater that the width of the second top grooves. Specification only states that the top grooves and the sub grooves may have the same or different widths (¶ 0038).
Therefore, it would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to have modified the first and second top grooves of Kirchner as modified by Mukai, Uzoh, and Bajaj to make the width of the first top grooves is greater than that of the second top grooves in order to achieve different slurry drain rates for quality and effective CMP process. Such a modification would have involved a mere change in the size of a component. A change in size is generally recognized as being within the level of ordinary skill in the art. See MPEP 2144.04(IV)(A).
Regarding claim 4, Kirchner as modified by Mukai, Uzoh, and Bajaj teaches the method as in the rejection of claim 1, wherein the second top pad comprises second microchannels extending through a thickness of the second top pad (Kirchner, col. 5:51-52 and 6:22-29, slurry drain holes 354 (correspond to the recited microchannels) are aligned with pad bottom drain grooves 362; see also similarly configured drain holes 308 in Figure 3A. Thus, the slurry drain holes extend through a thickness of the top pad. Since the second pad's features are identical to the first pad's features as discussed in claim 1 above, the second microchannels also extend through a thickness of the second top pad).
Regarding claim 5, Kirchner as modified by Mukai, Uzoh, and Bajaj teaches the method as in the rejection of claim 4, but does not disclose a largest diameter of each of the first microchannels is greater than a largest diameter of each of the second microchannels.
As discussed in claims 1-4 above, however, Kirchner as modified by Mukai, Uzoh, and Bajaj teaches the first microchannels and the second microchannels except for having different diameters (Kirchner, col. 6:13-20, drain holes may have a diameter of 0.8 mm). On the other hand, specification of the instant application is silent regarding reason why the diameter of the first microchannels needs to be greater that the depth of the second microchannels.
Therefore, it would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to have modified the first and second microchannels of Kirchner as modified by Mukai, Uzoh, and Bajaj to make the largest diameter of the first microchannels is greater than the largest diameter of the second microchannels in order to achieve different slurry drain rates for quality and effective CMP process. Modification of microchannel diameters including the largest diameters of the first microchannels and the second microchannels would have involved a mere change in the size of a component. A change in size is generally recognized as being within the level of ordinary skill in the art. See MPEP 2144.04(IV)(A).
Claim 6 is rejected under 35 U.S.C. 103 as being unpatentable over Kirchner in view of Mukai, Uzoh, and Bajaj as applied to claim 1 above, and in further view of Campbell et al. (US 6,217,412, hereinafter Campbell).
Regarding claim 6, Kirchner as modified by Mukai, Uzoh, and Bajaj teaches the method as in the rejection of claim 1, further comprising:
dispensing a second slurry over the second polishing pad (Kirchner, fig. 2A and col. 2:55-59, slurry is applied to the pad 220; Mukai ¶ 0003, 0054, the first pad is replaced with the second pad, and a second polishing is carried out. Therefore, a second slurry is dispensed to the second polishing pad); and
rotating the second polishing pad (Kirchner, col. 2:55-3:12, Kirchner teaches rotating the polishing pad by rotating the platen; Mukai ¶ 0003, 0054, the first pad is replaced with the second pad, and a second polishing is carried out. Therefore, the second polishing pad is rotated during polishing), but does not disclose rotating the first polishing pad comprises a first rotation speed, rotating the second polishing pad comprises a second rotation speed, and wherein the first rotation speed is different than the second rotation speed.
Campbell teaches, in an analogous CMP field of endeavor, the first polishing pad comprises a first rotation speed, rotating the second polishing pad comprises a second rotation speed, and wherein the first rotation speed is different than the second rotation speed (col. 2:29-35, wafer polishing is done by using a first polishing pad, followed by a second polishing pad after replacing the first polishing pad; col. 4:46-54, rotational speed of the second polishing pad may be increased).
It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to have modified the polishing method of Kirchner as modified by Mukai, Uzoh, and Bajaj to provide the different rotation speeds for the first and second polishing pads as taught by Campbell in order to make sure a removal rate is acceptable throughout the entire polishing process (Campbell col. 4:46-54).
Claims 7 and 8 are rejected under 35 U.S.C. 103 as being unpatentable over Kirchner in view of Mukai, Uzoh, and Bajaj, as applied to claim 1 above, and in further view of Chen et al. (US 2015/0336236, hereinafter Chen).
Regarding claim 7, Kirchner as modified by Mukai, Uzoh, and Bajaj teaches the method as in the rejection of claim 1, but does not disclose explicitly the first pattern is different than the second pattern.
Chen teaches, in an analogous CMP field of endeavor, the first pattern is different than the second pattern (figs. 2 ,4 and ¶ 0031, a polishing surface may have concentric grooves, spiral grooves, radial grooves, cross-hatching, or any geometric pattern. As discussed in claim 1, any polishing pad can be the first polishing pad or the second polishing pad, therefore, any different grooves can be the first top grooves and the second top grooves).
It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to have modified the top pad of Kirchner as modified by Mukai, Uzoh, and Bajaj to provide the different patterns as taught by Chen in order to achieve effective polishing operation in consideration of mechanism among substrate, polishing liquid, and polishing surface (Chen ¶ 0032).
Regarding claim 8, Kirchner as modified by Mukai, Uzoh, Bajaj, and Chen teaches the method as in the rejection of claim 7, wherein one of the first pattern and the second pattern comprises concentric circles, and wherein the other of the first pattern and the second pattern comprises radial lines (Chen, ¶ 0031, a polishing surface may have concentric grooves and radial grooves. As discussed in claim 1, any polishing pad can be the first polishing pad, the second polishing pad, or more. Therefore, one polishing pad can have the concentric grooves and another pad can have the radial grooves).
It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to have modified the top pad of Kirchner as modified by Mukai, Uzoh, and Bajaj to provide top pads having concentric grooves and radial grooves as taught by Chen in order to achieve effective polishing operation in consideration of mechanism among substrate, polishing liquid, and polishing surface (Chen ¶ 0032).
Claims 10-12 are rejected under 35 U.S.C. 103 as being unpatentable over Kirchner (US 6,692,338, cited on 07/26/2023 IDS), in view of Mukai et al. (US 2017/0312886, hereinafter Mukai) and Bajaj et al. (CN 107078048A, hereinafter Bajaj).
Regarding claim 10, Kirchner discloses a method of performing a wafer polishing step, wherein the first polishing pad comprising:
a first bottom pad, the first bottom pad comprising first bottom grooves along a top surface of the first bottom pad; and a first top pad, a bottom surface of the top pad facing the top surface of the first bottom pad (col. 6:22-29 and fig. 3A, a pad backing 304 [corresponds to the recited bottom pad] is disclosed as being used with fig. 3B’s pad and it faces the top pad. The pad backing 304 is disclosed as having drain grooves 325 [correspond to the first bottom grooves] in the backing’s top surface adjacent the other pad),
the first top pad (fig. 3A and col. 5:1-21, a pad 300 [corresponds to the recited top pad]) comprising:
first top grooves along a top surface of the first top pad (Kirchner, figs. 3A and 3B, the pad has the first top grooves 356 on a top surface);
first microchannels connecting the first top grooves to the first bottom grooves (Kirchner, fig. 3A and col. 5:1-21, 5:41-52, and 6:22-29, slurry drain holes 308 [correspond to the recited first microchannels] extend to the pad backing drain grooves 325 [correspond to the recited first bottom grooves] from the first top grooves 356),
second microchannels extending from the first top grooves to the first bottom pad and being misaligned with the first bottom grooves (see annotated Kirchner fig. 3A below, some microchannels are misaligned with the pad backing drain grooves 325 [correspond to the recited first bottom grooves]), but does not disclose the method comprises performing a first part of the wafer polishing step with a first polishing pad, performing a second part of the wafer polishing step with a second polishing pad, wherein the second polishing pad comprising: a second top pad, the second top pad comprising second top grooves along a top surface of the second top pad; and the first bottom pad.
Mukai teaches, in the analogous CMP field of endeavor, the method comprises performing a first part of the wafer polishing step with a first polishing pad, performing a second part of the wafer polishing step with a second polishing pad (¶ 0003, substrate processing is carried out in two polishing operations principally; ¶ 0054, After the first polishing, the first pad is detached and replaced with the second pad. Therefore, the second polishing is executed with the second pad), wherein the second polishing pad comprising: a second top pad, the second top pad comprising second top grooves along a top surface of the second top pad; and the first bottom pad (¶ 0054, the first pad can be detached from the support (equivalent to the bottom pad) and the first pad is replaced with the second pad. In other words, the second top pad is attached to the first bottom pad to form a second polishing pad).
As discussed in claim 1, the second pad's features are identical to the first pad's features. Therefore, the second top pad comprises second top grooves.
It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to have modified the second top pad of Kirchner as modified by Mukai to provide the second top grooves for slurry drainage so that effective polishing outcome can be achieved.
Furthermore, it would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to have modified the method of Kirchner to provide the second polishing with the second top pad as taught by Mukai in order to improve accuracy of planarization of a substrate (Mukai ¶ 0003).
However, Kirchner as modified by Mukai does not disclose a first diameter of the first microchannels at the first top grooves being greater than a second diameter of first the microchannels at the first bottom grooves.
As discussed in claim 1, Bajaj teaches, in the analogous CMP field of endeavor, the first microchannels having a conical shape (fig. 22 and Bajaj English translation, p. 30:22-33, a polishing pad comprises holes 2232 [correspond to the recited microchannels]. The holes 2232 have geometrical shape such as a cone or hollow truncated cone), and it is obvious to have a first diameter of the first microchannels at the first top grooves being greater than a second diameter of the first microchannels at the first bottom groove.
It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to have modified the microchannels of the polishing pad to have the first diameter of the microchannels at the first top grooves being greater than a second diameter of the microchannels at the first bottom grooves so that the holes/microchannels can receive slurry and other fluid and drain them effectively.
Kirchner as modified by Mukai and Bajaj does not disclose the first bottom grooves comprising a plurality of circles, an outermost circle of the plurality of circles being along an outer edge of the first bottom pad.
Kirchner discloses the pad bottom drain grooves 325 [correspond to the recited bottom grooves] in fig. 3A, but it is not clear whether they are in a form of a plurality of circles. Kirchner presents the slurry distribution grooves 356 on the polishing surface of the top pad are in a form of a plurality of concentric circles as shown in fig. 3B. The outermost circular groove is formed in the same curvature along an outer edge of the polishing pad. Examiner notes that Merriam-Webster dictionary presents one definition of the term “along” is in a line matching the direction of. The outer groove is disposed in the same direction as the outer edge of the pad. On the other hand, Kirchner teaches the slurry drain grooves in the pad bottom may be in any pattern including a radial pattern (col. 7:19-22), thus the grooves of the bottom pad can be disposed in a form of a plurality of concentric circles.
Therefore, it would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to have modified the bottom grooves of Kirchner as modified by Mukai and Bajaj to provide a plurality of circles as taught by Kirchner in order to facilitate slurry removal from the pad (Kirchner col. 7:20-21).
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Annotated Kirchner Fig. 3A
Regarding claim 11, Kirchner as modified by Mukai and Bajaj teaches the method as in the rejection of claim 10, wherein performing the first part of the wafer polishing step comprises:
dispensing a slurry over the first polishing pad (Kirchner, fig. 2A and col. 2:55-59, slurry is applied to the pad 220);
rotating the first polishing pad (Kirchner, col. 3:10-12, the pad rotates during polishing); and
pressing a semiconductor wafer against the first polishing pad (Kirchner, fig. 2A and col. 2:64-67, a carrier head 202 is moved toward the polishing pad. The carrier head 202 carries a wafer 210, thus it presses the wafer against the polishing pad).
Regarding claim 12, Kirchner as modified by Mukai and Bajaj teaches the method as in the rejection of claim 10, further comprising, after performing the first part of the wafer polishing step, replacing the first top pad with the second top pad (Mukai, ¶ 0003, substrate processing is carried out in two polishing operations principally; ¶ 0054, After the first polishing, the first pad is detached and replaced with the second pad).
It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to have modified the CMP method of Kirchner as modified by Mukai and Uzoh to replace the top pad after the first polishing step as taught by Mukai in order to improve accuracy of planarization of a substrate (Mukai ¶ 0003).
Claim 14 is rejected under 35 U.S.C. 103 as being unpatentable over Kirchner in view of Mukai and Bajaj, as applied to claim 10 above, and in further view of Uzoh.
Regarding claim 14, Kirchner as modified by Mukai and Bajaj teaches the method as in the rejection of claim 10, but does not disclose the first microchannels are angled downward and outward from a center of the top surface of the first top pad.
Uzoh teaches, in the analogous CMP field of endeavor, the first microchannels are angled downward and outward from a center of the top surface of the first top pad (figs. 7e, 7f and col. 15:6-19, a polishing pad has grooves 770 on a surface of the polishing pad and channels 772 [correspond to the recited microchannels] through the polishing pad (fig. 7a). Figs. 7e and 7f show the channels are angled and extending downward. They can be disposed outward from a center of the top pad).
It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to have modified the microchannels of Kirchner as modified by Mukai and Bajaj to provide the slanted microchannels as taught by Uzoh in order to improve the control of slurry flow on the pad surface.
Claims 15, 16, and 22 are rejected under 35 U.S.C. 103 as being unpatentable over Kirchner (US 6,692,338, cited on 07/26/2023 IDS), in view of Tjaden et al. (US 6,135,856, hereinafter Tjaden), Uzoh et al. (US 6,413,388, cited on 07/26/2023 IDS, hereinafter Uzoh), Prasad et al. (CN 1805826A, hereinafter Prasad), and Tanoue et al. (US 6527969, hereinafter Tanoue).
Regarding claim 15, Kirchner discloses a method, comprising:
attaching a first polishing pad to a platen (see fig. 2A, polishing pad 220 is attached to a platen 208. Therefore, there is a step of attaching the polishing pad to the platen), the first polishing pad comprising:
a first top pad comprising first top grooves and first microchannels, the first top grooves being along a top surface of the first top pad, the first microchannels extending from the first top grooves to a bottom surface of the first top pad (fig. 3B, slurry distribution grooves 356 [corresponds to the top groove] are disposed on the polishing surface 358 of the polishing pad; col. 5:51-52 and 6:22-29, slurry drain holes 354 [corresponds to the microchannel] are disposed on the polishing surface of the polishing pad and are aligned with pad bottom drain grooves 362; see also similarly configured drain holes 308 in Figure 3A), the first top grooves comprising a first circular groove along an outer edge of the first top pad (fig. 3B, the slurry distribution grooves 356 [corresponds to the top grooves] are disposed in a form of a plurality of concentric circles. The groove is formed in the same curvature along an outer edge of the top polishing pad); and
a first bottom pad comprising first bottom grooves, the first bottom grooves being along a top surface of the first bottom pad (col. 6:22-29 and fig. 3A, a pad backing 304 [corresponds to the recited bottom pad] is disclosed as being used with fig. 3B’s pad and it faces the top pad. The pad backing is disclosed as having drain grooves 325 [correspond to the recited bottom grooves] in the backing’s top surface adjacent the other pad);
dispensing a slurry over the first polishing pad (fig. 2A and col. 2:55-59, slurry is applied to the pad 220);
rotating the platen (col. 3:10-12, the pad rotates during polishing); and
polishing a wafer with the first polishing pad and the slurry (fig. 2A and col. 2:55-67, a wafer 220 is polished by contacting a polishing surface 212 of the polishing pad 220 while dispensing slurry from a conduit 206),
wherein polishing the wafer with the first polishing pad removes first particles from the wafer, and wherein the first particles have a higher specific gravity than the slurry (col. 1:12-23, in chemical mechanical polishing, a polishing pad rotates to remove a layer of a wafer. As discussed in 112(b) rejection, the removed particles by polishing have higher specific gravity than the slurry), but does not disclose the first bottom grooves comprising a second circular groove along an outer edge of the first bottom pad.
Kirchner discloses the pad bottom drain grooves 325 [correspond to the recited bottom grooves] in fig. 3A, but it is not clear whether they are in a form of a plurality of circles. Kirchner discloses the slurry distribution grooves 356 on the polishing surface of the top pad are disposed in a form of a plurality of concentric circles as shown in fig. 3B. The outermost circular groove is formed in the same curvature along an outer edge of the polishing pad. Because Kirchner teaches the slurry drain grooves in the pad bottom may be in any pattern including a radial pattern (col. 7:19-22), the grooves in the bottom pad can be disposed as a plurality of concentric circles like the grooves of the top pad.
Therefore, it would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to have modified the bottom grooves of Kirchner to provide the second circular groove along an outer edge of the first bottom pad as taught by Kirchner in order to facilitate slurry removal from the pad (Kirchner col. 7:20-21).
Kirchner does not disclose a depth of the first bottom grooves extending a partial thickness of the first bottom pad.
Tjaden teaches, in an analogous CMP field of endeavor, a depth of the first bottom grooves extending a partial thickness of the first bottom pad (fig. 4 and col. 5:20-23, a lower pad 312 (corresponds to the recited bottom pad) comprises grooves 330A, 330B wherein the grooves extend a partial thickness of the lower pad).
It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to have modified the bottom pad of Kirchner to provide the groove extending the partial thickness of the bottom pad as taught by Tjaden. The partial thickness grooves instead of the full thickness grooves, may help the bottom pad to withstand great amount of pressure during polishing operation to maintain a structural integrity of the polishing apparatus.
Kirchner as modified by Tjaden does not disclose a particular microchannel of the first microchannels comprising opposing sidewalls extending from the first top grooves to the bottom surface of the first ton pad.
Uzoh teaches, in the analogous CMP field of endeavor, a particular microchannel of the first microchannels comprising opposing sidewalls extending from the first top groove to the bottom surface of the first top pad (fig. 7a and col. 15:6-23, a polishing pad has grooves 770 on a surface of the polishing pad and channels 772 [correspond to the recited microchannels] through the polishing pad (fig. 7a)).
It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to have modified the microchannels of Kirchner as modified by Tjaden to provide the microchannels extending from the top groove as taught by Uzoh in order to improve the control of slurry flow on the pad surface.
Kirchner as modified by Tjaden and Uzoh does not disclose the entireties of the opposing sidewalls of the microchannel being non-parallel to one another in a side view cross-section.
Prasad teaches, in an analogous CMP field of endeavor, the entireties of the opposing sidewalls of the microchannel being non-parallel to one another in a side view cross-section (fig. 3, a polishing layer 12 [corresponds to the recited top pad] comprises an aperture 20 [corresponds to the recited microchannel] wherein the entireties of the opposing sidewalls of the aperture 20 is non-parallel to one another in a side view cross-section).
It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to have modified the microchannel of Kirchner as modified by Tjaden and Uzoh to provide the non-parallel sidewalls along entireties of the opposing sidewalls as taught by Prasad. The aperture of Prasad has a conical shape with a large area on an upper side of the polishing pad so that it can collect large amount of used slurry for improving a polishing process.
Kirchner as modified by Tjaden, Uzoh, and Prasad does not disclose filtering the first particles from an exit portion of the slurry; and recycling the filtered exit portion of the slurry into the slurry.
Tanoue teaches, in an analogous CMP field of endeavor, filtering the first particles from an exit portion of the slurry; and recycling the filtered exit portion of the slurry into the slurry (fig. 1 and col. 5:25-6:50, rejuvenating polishing slurry method includes recovering slurry waste (A), filtering solids (E and F), and supplying recycled polishing slurry (L)).
It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to have modified the polishing method of Kirchner as modified by Tjaden, Uzoh, and Prasad to provide the filtering and recycling slurry as taught by Tanoue for decreasing cost, safe waste disposal, and environment protection (Tanoue col. 1:40-46).
Regarding claim 16, Kirchner as modified by Tjaden, Uzoh, Prasad, and Tanoue teaches the method as in the rejection of claim 15, wherein each of the first microchannels connects one of the first top grooves to a corresponding one of the first bottom grooves (Kirchner, fig. 3A and col. 5:1-21, 5:41-52, and 6:22-29, slurry drain holes 308 [correspond to the recited microchannels] extend to the pad backing drain grooves 325 [correspond to the recited bottom grooves]).
Regarding claim 22, Kirchner as modified by Tjaden, Uzoh, Prasad, and Tanoue teaches the method as in the rejection of claim 15, wherein the first microchannels comprise an outer microchannel along the outer edge of the first top pad (Kirchner, fig. 3B, the top pad 350 includes a plurality of slurry drain holes 354 [correspond to the recited first microchannels]. The drain holes are disposed concentrically from a center of the top pad. The outer drain holes are disposed along the curvature following the outer edge of the first top pad), and wherein the outer microchannel connects the first circular groove of the first top grooves to the second circular groove of the first bottom grooves (Kirchner, fig. 3A and col. 5:1-21, 5:41-52, and 6:22-29, as discussed in the rejection of claim 1, fig. 3A shows similarly configured slurry drain holes 308 [correspond to the recited microchannels] which extend to the pad backing drain grooves 325 [correspond to the recited bottom grooves] from the first top grooves 356).
Claims 17-19 are rejected under 35 U.S.C. 103 as being unpatentable over Kirchner in view of Tjaden, Uzoh, Prasad, and Tanoue, as applied to claim 15 above, and in further view of Mukai.
Regarding claim 17, Kirchner as modified by Tjaden, Uzoh, Prasad, and Tanoue teaches the method as in the rejection of claim 15, wherein the top pad comprises top grooves and microchannels, wherein the top grooves are along a top surface of the top pad, wherein the microchannels connect the top grooves to the first bottom grooves of the first bottom pad as discussed in claim 15, but does not disclose the second top pad, second top grooves, second microchannels. Kirchner also does not disclose removing the first polishing pad from the platen; replacing the first top pad with a second top pad to form a second polishing pad, attaching the second polishing pad to the platen; and polishing the wafer with the second polishing pad.
Mukai teaches, in the analogous CMP field of endeavor, replacing the first top pad with a second top pad (¶ 0054). As discussed in claim 1, the second top pad has the identical features of the first top pad, therefore, the second pad has the recited second top grooves and second microchannels. Mukai further teaches replacing the first top pad with a second top pad to form a second polishing pad (¶ 0054). Since Kirchner teaches attaching the polishing pad to the platen; and polishing the wafer with the polishing pad (fig. 2A and col. 2:55-67), Kirchner as modified by Mukai teaches attaching the second polishing pad to the platen; and polishing the wafer with the second polishing pad.
It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to have modified the CMP method of Kirchner as modified by Tjaden and Uzoh to provide the second top pad having the second top grooves and the second microchannels as taught by Mukai for replacement purposes when the first top pad has become worn or broken without having to replace the entire pad construct (including the sub pad/backing).
Kirchner as modified by Tjaden, Uzoh, Prasad, Tanoue, and Mukai teaches polishing the wafer with the second polishing pad removes second particles from the wafer (Kirchner col. 1:12-23, in chemical mechanical polishing, a polishing pad rotates to remove a layer of a wafer. Claim does not define what the second particles are. Thus, any particles removed by polishing can be the second particles).
Finally, although Kirchner as modified by Tjaden, Uzoh, Prasad, Tanoue, and Mukai does not disclose explicitly the method of removing the first polishing pad from the platen, Kirchner teaches the method of attaching the first polishing pad to the platen as discussed above. Therefore, it would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to have modified the method of Kirchner to remove the first polishing pad from the platen in order to perform service or replacement of the top pad.
Regarding claim 18, Kirchner as modified by Tjaden, Uzoh, Prasad, Tanoue, and Mukai teaches the method as in the rejection of claim 17, wherein a depth of the first top grooves is greater than a depth of the second top grooves.
As discussed similarly in claim 1, Kirchner as modified by Mukai and Uzoh teaches the first top grooves and the second top grooves having depths except for the different groove depths (Kirchner, col. 6:13-20, drain grooves may have a depth of 0.8 mm). On the other hand, specification of the instant application is silent regarding reason why the depth of the first top grooves needs to be greater that the depth of the second top grooves.
Therefore, it would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to have modified the first and second top grooves of Kirchner as modified by Tjaden, Uzoh, Prasad, Tanoue, and Mukai to make the depth of the first top grooves is greater than that of the second top grooves in order to achieve different slurry drain rates for quality and effective CMP process. Such a modification would have involved a mere change in the size of a component. A change in size is generally recognized as being within the level of ordinary skill in the art. See MPEP 2144.04(IV)(A).
Regarding claim 19, Kirchner as modified by Tjaden, Uzoh, Prasad, Tanoue, and Mukai teaches the method as in the rejection of claim 17, wherein a diameter of the first microchannels is greater than a diameter of the second microchannels.
As discussed similarly in claim 5, Kirchner as modified by Mukai and Uzoh teaches the first microchannels and the second microchannels except for having different diameters (Kirchner, col. 6:13-20, drain holes may have a diameter of 0.8 mm). On the other hand, specification of the instant application is silent regarding reason why the diameter of the first microchannels needs to be greater that the depth of the second microchannels.
Therefore, it would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to have modified the first and second microchannels of Kirchner as modified by Tjaden, Uzoh, Prasad, Tanoue, and Mukai to make the diameter of the first microchannels is greater than that of the second microchannels in order to achieve different slurry drain rates for quality and effective CMP process. Such a modification would have involved a mere change in the size of a component. A change in size is generally recognized as being within the level of ordinary skill in the art. See MPEP 2144.04(IV)(A).
Claim 20 is rejected under 35 U.S.C. 103 as being unpatentable over Kirchner in view of Tjaden, Uzoh, Prasad, Tanoue, and Mukai, as applied to claim 17 above, and in further view of Hirose et al. (WO 2004043648A1, hereinafter Hirose).
Regarding claim 20, Kirchner as modified by Tjaden, Uzoh, Prasad, Tanoue, and Mukai teaches the method as in the rejection of claim 17, further comprising: removing the second polishing pad from the platen; and polishing the wafer with the third polishing pad (as discussed in claims 15 and 17 above, Kirchner teaches the method of removing the polishing pad from the platen and polishing the wafer with a polishing pad), but does not disclose replacing the first bottom pad with a second bottom pad to form a third polishing pad.
Hirose teaches, in an analogous CMP field of endeavor, a method of replacing a lower layer of a polishing pad (Hirose English translation, p. 8:7-11).
It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to have modified the polishing method of Kirchner as modified by Tjaden, Uzoh, Prasad, Tanoue, and Mukai to replace the bottom pad as taught by Hirose. A bottom pad can be deformed due to pressure provide on a polishing pad. Thus, replacing the bottom pad ensures the consistent polishing outcome (Hirose English translation, p. 8:7-11).
Kirchner as modified by Tjaden, Uzoh, Prasad, Tanoue, Mukai, and Hirose does not disclose explicitly forming and polishing with a third polishing pad. However, Mukai and Hirose teach replacing the top pad or the bottom pad to form a new polishing pad. Since a second polishing pad can be made, it would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to have modified the polishing method of Kirchner as modified by Tjaden, Uzoh, Prasad, Tanoue, Mukai, and Hirose to form third or additional polishing pad in order to maintain the good polishing outcome.
Claim 21 is rejected under 35 U.S.C. 103 as being unpatentable over Kirchner in view of Mukai and Bajaj, as applied to claim 10 above, and in further view of Tjaden.
Regarding claim 21, Kirchner as modified by Mukai and Bajaj discloses the method as in the rejection of claim 10, but does not disclose a depth of the first bottom grooves extends a partial thickness of the first bottom pad.
Tjaden teaches, in an analogous CMP field of endeavor, a depth of the first bottom grooves extends a partial thickness of the first bottom pad (fig. 4 and col. 5:20-23, a lower pad 312 (corresponds to the recited bottom pad) comprises grooves 330A, 330B wherein the grooves extend a partial thickness of the lower pad).
It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to have modified the bottom pad of Kirchner as modified by Mukai and Bajaj to provide the groove extending the partial thickness of the bottom pad as taught by Tjaden. The partial thickness grooves instead of the full thickness grooves, may help the bottom pad to withstand great amount of pressure during polishing operation to maintain a structural integrity of the polishing apparatus.
Response to Arguments
Applicant's arguments have been fully considered but they are not persuasive.
Applicant argues claim limitations reciting dimensional relationships between different recited features cannot be rejected as changes in size rationale. Examiner respectfully disagrees.
Claim 1 recites the lowest depth of the first top grooves is greater than a lowest depth of the first bottom grooves; and a lowest depth of the second top grooves is less than the lowest depth of the first bottom grooves. Claims 2 and 3 recite a width of each of the first top grooves is greater than a width of each of the second top grooves. Claim 5 recites a largest diameter of each of the first microchannels is greater than a largest diameter of each of the second microchannels. Claim 18 recites a depth of the first top grooves is greater than a depth of the second top grooves. Claim 19 recites a diameter of the first microchannels is greater than a diameter of the second microchannels.
However, specification of the instant application only states that the top grooves and the sub grooves may have the same or different depths (¶ 0037); and the top grooves and the sub grooves may have the same or different widths (¶ 0038). On the other hand, specification of the instant application is silent regarding the diameter difference between the first microchannels and the second microchannels; and regarding the depth difference between the first top grooves and the second top grooves.
Specification does not articulate reasons for the recited features. Therefore, it appears there is no particularity to set the recited depths, widths, or diameters of the grooves or microchannels. They are just possible depth, width, or diameter combinations of the microchannels or the grooves. Therefore, it is reasonable to use the change of size rationale to reject the exemplary features because Kirchner teaches the grooves in the pad may be in any pattern which facilitates slurry removal from the pad (Kirchner col. 7:19-21). A change in size is generally recognized as being within the level of ordinary skill in the art (MPEP 2144.04(IV)(A)).
Applicant’s arguments with respect to the rejection(s) of claim 15 under 35 U.S.C. §103 have been fully considered and are persuasive. Therefore, the rejection has been withdrawn. However, upon further consideration, a new ground(s) of rejection is made in view of Prasad and Tanoue.
Applicant argues the cited references do not teach or suggest the amended claim limitations of claim 15 that the microchannel has non-parallel sidewalls along the entireties of the opposing sidewalls and the slurry is filtered and recycled. Examiner respectfully disagrees. Prasad teaches apertures through a thickness of a polishing pad and the aperture/microchannel has non-parallel sidewalls because he has a conical shape (Prasad fig. 3). Regarding the filtering and recycling of the slurry, Tanoue teaches the amended claim limitations (Tanoue fig. 1).
Regarding the amendments in claims 1 and 10, which are about the depths of the grooves and the misaligned grooves, Kirchner teaches the amended claim limitations as discussed in the rejections of claims 1 and 10 above.
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.
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/S.J.C./Examiner, Art Unit 3723
/DAVID S POSIGIAN/Supervisory Patent Examiner, Art Unit 3723