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 .
Claim Rejections – 35 U.S.C. § 112
The following is a quotation of 35 U.S.C. § 112(b):
(b) CONCLUSION.—The specification shall conclude with one or more claims particularly pointing out and distinctly claiming the subject matter which the inventor or a joint inventor regards as the invention.
The following is a quotation of 35 U.S.C. § 112 (pre-AIA ), second paragraph:
The specification shall conclude with one or more claims particularly pointing out and distinctly claiming the subject matter which the applicant regards as his invention.
Claims 1-4 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.
Claim 1 recites the limitation “simultaneously moving the grinding unit and the chuck table, in the radial direction of the chuck table” (lines 21-22, 28-29 (two instances)). This limitation is indefinite because it is unclear and fails to inform a person of ordinary skill in the art what this means. First, it is unclear what the term “simultaneously” modifies. Does this refer to the radial movement of both the grinding unit and the chuck table, or does this refer to their rotational movements? Second, it is unclear whether this means that both the grinding unit the chuck table move simultaneously, but where only one of the grinding unit or the chuck table moves in the radial direction of the chuck table (see the limitation “relatively moving the grinding unit and the chuck table in a radial direction of the chuck table” in lines 16-17), or whether both the grinding unit and the chuck table move simultaneously, where both the grinding unit and the chuck table move in a radial direction of the chuck table. Third, with respect to the term “the radial direction”, the plain language of the limitation appears to mean that both the grinding unit and the chuck table are moving in the same radial direction, as opposed to moving in opposite radial directions. To the extent the same radial direction is the proper interpretation, it appears that moving both the grinding unit and the chuck table together in the same radial direction may not supported by the specification. Examiner suggests clarifying the use of the term “simultaneously” and also using terms such as “an inward radial direction of the chuck table” and “outward radial direction of the chuck table” for further clarification. For examination purposes, this limitation is interpreted as best understood. Claims 2-4 are rejected on the basis they incorporate this limitation of claim 1.
Claim Rejections – 35 U.S.C. § 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.
Seddon in view of Yamamoto, Yoshida, Kitano, and Boyd
Claims 1-4 are rejected under 35 U.S.C. § 103 as being unpatentable over US 20180040469 A1 (“Seddon”) in view of US 20200013664 A1 (“Yamamoto”), US 20080090505 A1 (“Yoshida”), US 20220344149 A1 (“Kitano”), and US 20060063470 A1 (“Boyd”).
Seddon pertains to a substrate processing apparatus (Abstr.; Figs. 2a-2c, 3a-3i). Yamamoto pertains to a substrate processing apparatus (Abstr.; Fig. 15). Yoshida pertains to a substrate processing apparatus (Abstr.; Figs. 2, 9A-B). Kitano pertains to a substrate processing apparatus (Abstr.; Figs. 9a-c). Boyd pertains to a substrate processing apparatus (Abstr.; Figs. 2A-B, 4). These references are in the same field of endeavor.
Regarding claim 1, Seddon discloses a workpiece grinding method of grinding a back surface of a workpiece having, on a front surface thereof, a device region and an outer peripheral surplus region surrounding the device region, to form a recessed portion in the back surface, thereby forming a circular thin plate portion and an annular protrusion portion surrounding the circular thin plate portion (Figs. 2a-2c, 3a-3i; ¶¶ 0012-0013, 0017-0018, grinding method for wafer 100 having device region on front surface 110 and a formed recessed portion on back surface 108, with annular protrusion portion 146 and circular thin plate portion 144 (Fig. 3h); Examiner notes that this limitation includes a recitation of intended use. A recitation of the intended use of the claimed invention must result in a structural difference (or, in the case of process claims, a manipulative difference) between the claimed invention and the prior art in order to patentably distinguish the claimed invention from the prior art. If the prior art structure is capable of performing the intended use, then it meets the claim. In re Schreiber, 128 F.3d 1473, 1477 (Fed. Cir. 1997) (“It is well settled that the recitation of a new intended use for an old product does not make a claim to that old product patentable.”); MPEP § 2111.02(II)), the method comprising:
a holding step of holding the front surface of the workpiece with a holding surface of a chuck table that is rotatable about an axis... (Figs. 3a-3i, front surface 110 is held on a holding surface of a “chuck table” that rotates about its axis (the wafer 100 cannot be floating in midair during the disclosed operation, whatever it is resting on (inherently) is the “holding surface” of a “chuck table”; ¶ 0018, “the entire back surface 108 undergoes a first grinding operation with grinder or grinding wheel 132 rotating and semiconductor wafer 100 rotating to remove a portion of base substrate material 102”);
a...grinding step of grinding the back surface of the workpiece by relatively moving a grinding unit and the chuck table toward each other along the axis... (Figs. 3f-3i; ¶¶ 0025-0031, back surface 144 of wafer 100 is ground by a vertical movement of the grinding unit 140/141 towards the wafer 100),
the grinding unit including a spindle having a distal end portion to which a grinding wheel is mounted, the grinding wheel including an annular base and a plurality of grinding stones that are arranged in an annular pattern on one surface of the base and that have outer peripheral surfaces defining a circle of a diameter not greater than a radius of the workpiece (Figs. 3f-i, grinding unit 140/141 with spindle, grinding wheel 140, and annularly arranged grinding stones 141 on the bottom surface of grinding wheel 140, where the outer peripheral surfaces of the grinding stones 141 define a circle with a diameter smaller than the radius of wafer 100; see discussion below re “an annular base”);
and a radially directed grinding step of grinding the back surface of the workpiece by relatively moving the grinding unit and the chuck table in a radial direction of the chuck table, the radial direction being orthogonal to the axis (Figs. 3f-3i; ¶¶ 0025-0031, radial grinding step performed by grinding wheel 140),
wherein the radially directed grinding step includes one of or both
an inwardly directed grinding step of grinding the workpiece while rotating the grinding wheel about a central axis of the grinding unit and the holding surface about the axis of the rotary shaft of the chuck table, and...moving the grinding unit...in the radial direction of the chuck table, from a first position where bottom surfaces of the grinding stones and the axis of the chuck table do not overlap each other to a second position where the bottom surfaces of the grinding stones and the axis of the chuck table overlap each other (Figs. 3f-3i; ¶¶ 0018, 0025-0031, while both the grinding wheel and holding surface are rotating as recited, the inwardly moving radial grinding step starts where grinding wheel 140 is near the outside edge of wafer 100 (where the grinding stones do not overlap the central chuck table axis (first position)) and grinding wheel 140 moves inward to overlap the central chuck table axis (second position)),
and an outwardly directed grinding step of grinding the workpiece while...moving the grinding unit...in the radial direction of the chuck table, from the second position where the bottom surfaces of the grinding stones and the axis of the chuck table overlap each other to the first position where the bottom surfaces of the grinding stones and the axis of the chuck table do not overlap each other (Figs. 3f-3i; ¶¶ 0025-0031, the outwardly moving radial grinding step starts at the second position (where the grinding stones overlap the central chuck table axis) and moves outward towards the outside edge of wafer 100 to the first position (where the grinding stones do not overlap the central chuck table axis)).
Seddon does not explicitly disclose:
a holding step of holding the front surface of the workpiece with a holding surface of a chuck table that is rotatable about an axis of a rotary shaft;
a rotary-shaft direction grinding step of grinding the back surface of the workpiece by relatively moving a grinding unit and the chuck table toward each other along the axis of the rotary shaft of the chuck table,
the grinding unit including a spindle having a distal end portion to which a grinding wheel is mounted, the grinding wheel including an annular base and a plurality of grinding stones that are arranged in an annular pattern on one surface of the base,
an inwardly directed grinding step of grinding the workpiece while rotating the grinding wheel about a central axis of the grinding unit and the holding surface about the axis of the rotary shaft of the chuck table, and simultaneously moving the grinding unit and the chuck table, in the radial direction of the chuck table, from a first position where bottom surfaces of the grinding stones and the axis of the chuck table do not overlap each other to a second position where the bottom surfaces of the grinding stones and the axis of the chuck table overlap each other,
and an outwardly directed grinding step of grinding the workpiece while simultaneously moving the grinding unit and the chuck table, in the radial direction of the chuck table, from the second position where the bottom surfaces of the grinding stones and the axis of the chuck table overlap each other to the first position where the bottom surfaces of the grinding stones and the axis of the chuck table do not overlap each other.
However, the Seddon/Yamamoto/Yoshida/Kitano/Boyd combination makes obvious this claim.
Yamamoto discloses:
a holding step of holding the front surface of the workpiece with a holding surface of a chuck table that is rotatable about an axis of a rotary shaft (Fig. 15; ¶ 0090, front surface of wafer 11 is held on surface 32a of chuck table 90 that rotates on an axis);
the grinding unit including a spindle having a distal end portion to which a grinding wheel is mounted, the grinding wheel including an annular base and a plurality of grinding stones that are arranged in an annular pattern on one surface of the base (Fig. 15; ¶¶ 0062-0063, grinding unit 70 with spindle 72 and grinding wheel 76 with annular base 78a with annularly arranged grinding stones 78b).
Yoshida discloses:
a holding step of holding the front surface of the workpiece with a holding surface of a chuck table that is rotatable about an axis of a rotary shaft (Figs. 3A-B; ¶¶ 0034-0035, front surface of wafer 1 is held on a surface of chuck table 30 that rotates about its rotary shaft);
a rotary-shaft direction grinding step of grinding the back surface of the workpiece by relatively moving a grinding unit and the chuck table toward each other along the axis of the rotary shaft of the chuck table (Figs. 7A-B, 8A-B, 9A, back surface of wafer 1 is ground by moving the grinding unit 46 towards the chuck table in the axis direction).
Boyd discloses:
an inwardly directed grinding step of grinding the workpiece while rotating the grinding wheel about a central axis of the grinding unit and the holding surface about the axis of the rotary shaft of the chuck table, and simultaneously moving the grinding unit and the chuck table, in the radial direction of the chuck table, from a first position where bottom surfaces of the grinding stones and the axis of the chuck table do not overlap each other to a second position where the bottom surfaces of the grinding stones and the axis of the chuck table overlap each other (Figs. 2A-B, 4; ¶ 0048, the grinding stone of the grinding wheel 260 and the holding surface 201 both rotate as recited, where both the grinding wheel 260 and chuck table 201 move simultaneously in a radial direction (directions 221 and 209a/b, step 413 (Fig. 4)), from the first position to the second position as recited; ¶¶ 0023-0027),
and an outwardly directed grinding step of grinding the workpiece while simultaneously moving the grinding unit and the chuck table, in the radial direction of the chuck table, from the second position where the bottom surfaces of the grinding stones and the axis of the chuck table overlap each other to the first position where the bottom surfaces of the grinding stones and the axis of the chuck table do not overlap each other (Figs. 2A-B, 4; ¶ 0048, both the grinding wheel 260 and chuck table 201 move simultaneously in a radial direction (directions 221 and 209a/b, step 413 (Fig. 4)), from the second position to the first position as recited; ¶¶ 0023-0027).
It would have been obvious to one of ordinary skill in the art before the effective filing date of this application to combine the teachings of Yamamoto with Seddon by modifying the grinding wheel to have an annular base to attach the grinding stones. This would have been obvious to a person of ordinary skill in the art because Seddon teaches an annular arrangement of grinding stones attached to the base of the grinding wheel, but is silent regarding the shape of the base (Seddon Figs. 3f-i; ¶ 0018 “grinding wheel teeth 133”), and it would have been obvious to modify the base to be an annular shape like the arrangement of the grinding stones (“grinding wheel teeth 133”) so that there is additional clearance between a workpiece and the grinding wheel (i.e., the central portion) when the grinding stones become worn and only protrude slightly below the base surface of the grinding wheel. Applicant has not disclosed that having an annular base provides an advantage, solves any stated problem, or is used for any particular purpose and it appears that the device would perform equally well with other designs. Furthermore, absent a teaching as to criticality of this positioning as claimed, this particular arrangement is deemed to have been known by those skilled in the art since the specification and evidence of record fail to attribute any significance (novel or unexpected results) to this particular arrangement. In re Kuhle, 526 F.2d 553, 555 (CCPA 1975).
Further, to the extent Seddon does not disclose a chuck table and/or a rotary shaft, it would have been obvious to one of ordinary skill in the art before the effective filing date of this application to combine the teachings of Yoshida with the Seddon/Yamamoto combination by modifying the object that is holding wafer 100 of Seddon to be a chuck table that is rotatable about an axis of a rotary shaft (Seddon Figs. 3A-B; ¶¶ 0034-0035). This would have been obvious to a person of ordinary skill in the art because the use of a chuck table that is rotatable about its central rotary shaft to hold a wafer is well known in the art (see US 20160064230 A1 (“Nishihara”) Figs. 3-4, rotatable chuck table 10 with shaft; ¶ 0030; Yamamoto Fig. 15; ¶ 0090), and would be a case of simple substitution to the extent this is not already disclosed in Seddon.
Additionally, while Seddon discloses both the inwardly directed grinding step and the outwardly directed grinding step, Examiner notes that a radial or lateral grinding step is known in the art, and it is known that the a radial or lateral grinding step can be combined with a vertical grinding step, either separately or concurrently (Yoshida Figs. 9A-B; ¶¶ 0070-0071, a vertical grinding step is followed by a radially outward grinding step; Kitano Figs. 9a-c; ¶¶ 0059-0064, a vertical grinding step is concurrently performed with a radially inward grinding step, resulting in a sloped portion 56; see US 20130052812 A1 (“Nakata”) Figs. 4-5; ¶¶ 0022-0025, sloped portion 25 is ground with a vertical grinding step and a radially inward grinding step).
Finally, it would have been obvious to one of ordinary skill in the art before the effective filing date of this application to combine the teachings of Boyd with the Seddon/Yamamoto/Yoshida/Kitano combination to modify the chuck table to move horizontally (radially inward and outward) simultaneously with the horizontal grinding movement (radially inward and outward) of the Seddon grinding unit. This would have been obvious because this is a case of simple substitution, where horizontal movement of the grinding unit alone could be substituted for horizontal movement of both the grinding unit and the chuck table (e.g., in opposite horizontal directions, where their horizontal movement speeds are half of the horizontal movement speed of the grinding unit alone in the unmodified scenario), resulting in predictable, similar grinding results due to the fact the relative horizontal movement between the grinding unit and the chuck table can be controlled to be the same. Boyd discloses moving the grinding unit and/or the chuck table and makes no remarks regarding different results (Boyd ¶ 0048, “The method can also include an operation 413 for moving the wafer and/or grinding wheel relative to one another in a horizontal direction, i.e., parallel to the chuck surface upon which the wafer is being held. For example, in one embodiment, the chuck can be moved in a horizontal direction relative to the grinding wheel. In another embodiment, the grinding wheel can be moved in a horizontal direction relative to the chuck. In yet another embodiment, both the chuck and grinding wheel can be moved in a simultaneous manner.”). Notably, Applicant has not disclosed that the recited simultaneous horizontal movement (radially inward and outward) of both the grinding unit and chuck table provides an advantage, solves any stated problem, or is used for any particular purpose and it appears that the device would perform equally well with other designs. Furthermore, absent a teaching as to criticality of this method as claimed, this particular method is deemed to have been known by those skilled in the art since the specification and evidence of record fail to attribute any significance (novel or unexpected results) to this particular method. In re Kuhle, 526 F.2d 553, 555 (CCPA 1975).
Regarding claim 2, the Seddon/Yamamoto/Yoshida/Kitano/Boyd combination makes obvious the workpiece grinding method of claim 1 as applied above. Seddon further discloses wherein, in the radially directed grinding step (as modified in the Seddon/Yamamoto/Yoshida/Kitano/Boyd combination of claim 1), the inwardly directed grinding step and the outwardly directed grinding step are alternately repeated to grind the workpiece (Figs. 3f-3i; ¶¶ 0025-0031, inwardly and outwardly directed grinding steps shown).
To the extent this limitation is not explicitly disclosed in Seddon, it would have been obvious to one of ordinary skill in the art before the effective filing date of this application to alternately repeat the inwardly and the outwardly directed grinding steps for the reasons stated for claim 1. Examiner notes that in light of the prior art discussed for claim 1, alternately repeating the inwardly and the outwardly directed grinding step is a known procedure to remove material from a workpiece (i.e., to grind going back and forth on the workpiece surface). Applicant has not disclosed that alternately repeating the inwardly and the outwardly directed grinding steps provides an advantage, solves any stated problem, or is used for any particular purpose and it appears that the method would perform equally well with other procedures. Furthermore, absent a teaching as to criticality of this step as claimed, this particular step is deemed to have been known by those skilled in the art since the specification and evidence of record fail to attribute any significance (novel or unexpected results) to this particular step. In re Kuhle, 526 F.2d 553, 555 (CCPA 1975).
Regarding claim 3, the Seddon/Yamamoto/Yoshida/Kitano/Boyd combination makes obvious the workpiece grinding method of claim 1 as applied above. Seddon further discloses wherein the rotary-shaft direction grinding step and the radially directed grinding step (as modified in the Seddon/Yamamoto/Yoshida/Kitano/Boyd combination of claim 1) are concurrently performed to grind the workpiece, and the radially directed grinding step (as modified in the Seddon/Yamamoto/Yoshida/Kitano/Boyd combination of claim 1) includes both the inwardly directed grinding step and the outwardly directed grinding step (Figs. 3f-3i; ¶¶ 0025-0031, inwardly and outwardly directed grinding steps shown, concurrent with vertical grinding step).
To the extent this limitation is not explicitly disclosed in Seddon, it would have been obvious to one of ordinary skill in the art before the effective filing date of this application to perform the rotary-shaft direction grinding step (vertical grinding step) and the radially directed grinding step concurrently for the reasons stated for claim 1 (Kitano Figs. 9a-c; ¶¶ 0059-0064, a vertical grinding step is concurrently performed with a radially inward grinding step). Applicant has not disclosed that concurrently performing the rotary-shaft direction grinding step and the radially directed grinding step provides an advantage, solves any stated problem, or is used for any particular purpose and it appears that the method would perform equally well with other procedures. Furthermore, absent a teaching as to criticality of this step as claimed, this particular step is deemed to have been known by those skilled in the art since the specification and evidence of record fail to attribute any significance (novel or unexpected results) to this particular step. In re Kuhle, 526 F.2d 553, 555 (CCPA 1975).
Regarding claim 4, the Seddon/Yamamoto/Yoshida/Kitano/Boyd combination makes obvious the workpiece grinding method of claim 1 as applied above. Yamamoto further discloses wherein, in the holding step, the workpiece is held with the holding surface having a planarity of smaller than 10 µm in terms of roughness, and in the rotary-shaft direction grinding step and the radially directed grinding step, the workpiece held with the holding surface having the planarity is ground (Figs. 10A-C, 15; ¶¶ 0049, 0069, 0090, wafer 11 is held on a porous plate 32 having a holding surface 32a with a planar roughness of 5.0µm or less).
The obviousness rationale for claim 4 is the same as for claim 1, with the addition that it would have been obvious to one of ordinary skill in the art before the effective filing date of this application to modify Seddon to use the porous chuck design (having the recited roughness) of Yamamoto to hold the wafer during the recited grinding steps. This would have been obvious to a person of ordinary skill in the art because the use of a porous chuck with this level of planarity promotes an even suction force across the entire surface of the wafer, preventing wafer warpage and reducing defects in the process (Yamamoto ¶¶ 0069-0070, “As described above, the holding surface 32a of the porous plate 32 is flat and has a center-line average roughness Ra of 5.0 μm or less or a maximum height Ry of 25 μm or less. The pores 53 that are present between the glass particles 51 are spatially interconnected, providing a flow channel for a gas that extends from the reverse side 32d of the porous plate 32 to the holding surface 32a thereof...Since the porous plate 32 according to the present invention is made of glass particles 51 that are highly uniform in diameter and are nearly spherical compared to ceramics particles, the pores 53 provided by the interstices between the glass particles 51 are more uniform in size than the pores in a porous plate made of ceramics particles that are irregular in shape. Inasmuch as the highly uniform pores 53 are thus exposed on the holding surface 32a of the porous plate 32 of the porous chuck table 30 according to the present invention, the suction force developed in the holding surface 32a is rendered more uniform than the suction force developed in the holding surface of the porous plate made of ceramics particles”).
Response to Amendment
Applicant’s Amendment and remarks have been considered. Claims 1-5 are pending. Claim 5 has been withdrawn from further consideration under 37 C.F.R. § 1.142(b) as being drawn to a nonelected invention. Claims 1-4.
Claims – In light of Applicant’s claim amendments, the § 112(b) rejections are hereby withdrawn. However, see new § 112(b) rejection due to amendments.
Response to Arguments
Applicant’s arguments with respect to claim 1 have been considered. With respect to Seddon, Applicant mischaracterizes (Reply at 6-7) this reference because Seddon explicitly discloses a grinding wheel rotating about a central axis of the grinding unit (Figs. 3f-i, grinding wheel 140 rotates around spindle as shown), and at least inherently discloses a holding surface on a “chuck table” that rotates about its axis (¶ 0018, “a first grinding operation with grinder or grinding wheel 132 rotating and semiconductor wafer 100 rotating”). Further, this concept and the related limitations are made obvious by Yoshida as explained in the rejection of claim 1 above.
With respect to the “simultaneous moving the grinding unit and the chuck table, in the radial direction” limitation, Applicant’s arguments are moot because the new ground of rejection does not rely on any reference applied in the prior rejection of record for any teaching or matter specifically challenged in these arguments.
Applicant does not present any further arguments concerning the remaining claims.
Conclusion
Applicant’s amendment necessitated the new ground(s) of rejection presented in this Office action. Accordingly, THIS ACTION IS MADE FINAL. MPEP § 706.07(a). Applicant is reminded of the extension of time policy as set forth in 37 C.F.R. § 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 extension fee pursuant to 37 C.F.R. § 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 date of this final action.
Any inquiry concerning this communication or earlier communications from the examiner should be directed to KENT N SHUM whose telephone number is (703)756-1435. The examiner can normally be reached 1230-2230 EASTERN TIME M-TH.
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/KENT N SHUM/Examiner, Art Unit 3723
/MONICA S CARTER/Supervisory Patent Examiner, Art Unit 3723