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 .
Specification
The disclosure is objected to because of the following informalities:
Para. [0088] recites “sample 209” should be “sample 208.”
Appropriate correction is required.
Claim Objections
Claim 1 is objected to because the limitation “using one or more distal sensors…to measure one or more respective portions of the sample surface” omits the phrase “positions of” after “measure.”
Appropriate correction is required.
Claim Rejections - 35 USC § 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.
Claim 14 is 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 14 recites the limitation “the same distance from the stage.” There is insufficient antecedent basis for this limitation in the 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.
Claims 1-20 are rejected under 35 U.S.C. 103 as being unpatentable over US 2007/0035714 A1 [hereinafter Galburt] in view of US 2011/0193574 A1 [hereinafter Boer].
Regarding Claim 1:
Galburt teaches a method of obtaining topographical information about a sample surface (para. [0012]: “Measuring a topography of the Substrate.”), the method comprising:
projecting a multibeam of [irradiation] towards a sample along a multibeam path that intersects the sample in a multibeam processable area to process the sample surface in the multibeam processable area, the multibeam comprising a plurality of sub-beams having paths within the multibeam path (Fig. 1, para. [0049-0050, 0055-0058]: project radiation beam B through aperture 200 (“multibeam path”) onto target portion C (“multibeam-processable area”) of substrate W. Galburt also teaches “divide the radiation beam into a plurality of sub-beams”);
using a group of proximal sensors (Fig. 2- sensor 210/212) positioned proximate to the paths of the plurality of sub-beams to measure positions of respective portions of the sample surface relative to the proximal sensors (Fig. 2 and paras. [0064-0067, 0070-0071, 0080]: each set of sensors 210/212 is positioned immediately adjacent aperture 200 and is “located just outside the path of the exposing light.” The sensors measure the distance between the sensors and respective portions of the substrate surface);
using one or more distal sensors (Fig. 2- sensors 206/208) positioned more remotely from the paths of the sub-beams than the proximal sensors to measure one or more respective portions of the sample surface relative to the one or more distal sensors (Fig. 2 and paras. [0065-0070, 0072]: sensors 206/206 are positioned farther from the multibeam paths than sensors 210/212. All sensors may be gap, capacitive, fluid-gauge, proximity, optical, or acoustic sensors capable of measuring distance to the substrate surface);
providing relative movement between the multibeam processable area and the sample such that the multibeam processable area moves along a processing path in a reference frame of the sample (Figs. 1-3 and paras. [0050-0057, 0065, 0074]: move substrate stage WT338 relative to the exposing beam along movement axis 204 and exposes the substrate by scanning. In the substrate reference frame, the target/exposure area therefore moves along a processing path across the substrate); and
using at least the one or more distal sensors to obtain topographical information about the sample surface in a selected portion of the processing path before the multibeam processable area reaches the selected portion of the processing path (Figs. 2-4, paras. [0073, 0075, 0085-0089]: Galburt designates distal sensors 216/220 as a leading sensor that measures the substrate first and supplies a correction for substrate-surface topography. The leading-control signal is combined with the leading proximal topography sensor signal (from sensors 210 or 212) to generate a topography correction, which is delayed until the measured portion reaches the exposure aperture. Because the sensors and aperture are aligned along movement axis 204, the portion measured by the leading distal sensor distal sensors subsequently reaches the processable area at aperture 200).
However, Galburt does not expressly teach its irradiation beams are “charged particle beams.”
Boer teaches a charged-particle lithography machine whose projection lens and deflector stack forces and scans a plurality of charged-particle beamlets onto wafer surface (Fig. 31 and 32A, para. [0125]).
Therefore, it would have been obvious for an ordinary skilled person in the art, before the effective time of filing, to substitute Boer’s charged particle beamlets and associated projection system for Galburt’s optical sub-beams when a charged particle lithography application was desired. Boer expressly teaches that optical and charged particle lithography systems perform the same basic operation – scanning exposure beams over a wafer – and encounter the same wafer height and focal plane control problem (See Boer paras. [0004-0006]). Galburt also expressly contemplates magnetic, electromagnetic, and electrostatic projection systems (See Galburt para. [0042]). Thus, Galburt’s advance topography sensing and stage control arrangement could operate with Boer’s charged particle beamlets without changing its sensing principle, with the known sensor measurement being used to maintain the wafer in the focal plane of the charged particle projection system as taught by Boer.
Regarding Claim 15:
Galburt in view of Boer teaches an electron-optical apparatus, comprising:
a stage (Galburt -Fig 3. stage 338) configured to support a sample (Galburt -Fig.3. Substrate 340) having a sample surface;
a charged particle device (Boer -Fig. 31);
a sensing system (Galburt -Figs.1 and 2 sensor system 102) comprising: a group of proximal sensors (Galburt -Fig 2. Sensors 210/212) and one or more distal sensors (Galburt -Fig 2. Sensors 206/208);
a control system (Galburt -Fig 3. Controller 342);
The charged particle device and the control unit are each configured to perform steps essentially the same as recited in claim 1.
Regarding Claims 2 and 16:
Galburt in view of Boer teaches the method of claim 1 and the apparatus of claim 15, respectively. Galburt further teaches obtaining topographical information in one portion of the processing path while processing the sample surface using the multibeam in another portion of the processing path (Fig. 3 and paras. [0071. 0075, 0077]: the leading sensors measure topography before exposure while the stage continues scanning and the beam exposes another substrate portion).
Regarding Claim 3:
Galburt in view of Boer teaches the method of claim 1. Galburt further teaches controlling the position and/or orientation of the sample based on the obtained topographical information about the sample surface in the selected portion of the processing path when the multibeam processable area reaches that selected portion (paras. [0088-0089]: the topography measurements are digitally delayed until the measured portion reaches the explorer aperture; controller 342 then drives stage 338 based on the topography correction signal).
Regarding Claims 4 and 17:
Galburt in view of Boer teaches the method of claim 1. Galburt further teaches wherein the one or more distal sensors comprises at least one distal sensor positioned ahead of the multibeam processable area along the processing path (Fig. 2 and paras. [0073 and 0085]: depending on the scan direction, distal control sensor 216 or 220 is the leading sensor positioned ahead of aperture 200).
Regarding Claims 5 and 19:
Galburt in view of Boer teaches the method of claim 1. Galburt further teaches wherein the one or more distal sensors comprises at least one distal sensor configured to measure a portion of the sample surface in a same route as the multibeam processable area (Fig. 2 and para. [0065]: sensors pair 206/208 are positioned on opposite sides of aperture 200 along movement axis 204. Sensors 214/216 and 218/220 therefore measure wafer portions lying along the same scan route that subsequently passes beneath the exposure aperture).
Regarding Claim 6:
Galburt in view of Boer teaches the method of claim 5. Galburt further teaches wherein the at least one distal sensor comprises a distal sensor positioned substantially centrally with respect to a dimension of the multibeam processable area perpendicular to relative movement of the multibeam processable area along the route (Fig. 2 and para. [0065]: movement axis 204 passes through the center of exposure aperture 200. As shown in Fig. 2, outer distal sensors 214/216 and 218/220 are centered on that movement axis).
Regarding Claim 7:
Galburt in view of Boer teaches the method of claim 5. Galburt further teaches wherein
the at least one distal sensor comprises a rear sensor and a forward sensor (Figs. 2-3 and para. [0073]: depending on the scan direction, one of the distal control sensors 216 and 220 is the leading/forward sensor while the other is the trailing/rear sensors),
the rear sensor and the forward sensor being used to simultaneously measure portions of the sample surface on opposite sides of the multibeam processable area (paras. [0073, 0075]: the trailing sensor supplies continuous feedback while the leading sensor supplies additional topography correction, and the focus-control operation uses signals “from both the leading and trailing active control sensors …to keep the wafer surface at the point of exposure in the imaging focal plane”).
Regarding Claim 8:
Galburt in view of Boer teaches the method of claim 5. Galburt further teaches lateral sensor pairs 224/226, and a line-by-line exposure process in which the exposure area is moved over successive routes until the substrate is exposed (Fig. 2 and para. [0056]). Boer further teaches sensors A-C measure a line of the wafer surface, the calculated topography is stored and as the wafer advances, the stored information is used when that previously measured line reaches projection lens 104 (Figs. 31, 32A and paras. [0182-0184]). Thus, the combined system can be further modified to configure the side sensors 224/226 of Galburt as look-ahead sensor for an adjacent processing route as taught in Boer. In the modified system, sensor 224/226 measures a surface portion in the next adjacent route while the multibeam processable area processes the current route to obtain the height information for the next route during the current exposure. After the current route is completed, the stage shifts laterally and moves the multibeam processable area along the adjacent route and over the previously measured portion, as recited in claim 8.
Regarding Claims 9 and 18:
Galburt in view of Boer teaches the method of claim 1 and the apparatus of claim 15, respectively. Galburt further teaches wherein the group of proximal sensors comprise four proximal sensors positioned to measure four respective portions of the sample surface defining vertices of a shape having four sides (each proximal sensor set 210/212 contains four sensors. Fig. 2 shows corresponding proximal sensors on opposite sides of aperture 200; four corresponding upper/lower sensors define the vertices of a rectangular).
Regarding Claim 10:
Galburt in view of Boer teaches the method of claim 1. Galburt further teaches wherein the shape is a rectangle and the one or more distal sensors comprise a first distal sensor configured to measure a respective portion of the sample surface that is aligned with a center of the rectangle in a direction parallel to a first side of the rectangle (Fig. 2 and para. [0065]: for the rectangle defined using proximal sensors from sets 210/212, distal sensors 214/216 or 218/220 are aligned with its center along movement axis 204, parallel to the horizontal sides of the rectangle).
Regarding Claim 11:
Galburt in view of Boer teaches the method of claim 1. Galburt further teaches wherein the one or more distal sensors further comprises a second distal sensor configured to measure a portion of the sample surface that is aligned with the center of the rectangle in a direction parallel to a second side of the rectangle, the second side being orthogonal to the first side (claim 6, Fig. 2, paras. [0069, 0076]: additional distal pair 224/226 is positioned on central longitudinal axis 222, perpendicular to movement axis 204. It therefore supplies as second distal sensor aligned with the rectangle center parallel to its orthogonal side).
Regarding Claim 12:
Galburt in view of Boer teaches the method of claim 9. Boer further teaches wherein the one or more distal sensors comprise at least one distal sensor positioned such that the at least one distal sensor and two of the proximal sensors are configured to measure respective portions of the sample surface that, together with a center of the multibeam processable area, define vertices of a rhombus (Fig. 32A: distal sensor A, proximal sensors D and B, and the center of lens 104 form the four vertices of a square, which is a rhombus).
Regarding Claims 13 and 20:
Galburt in view of Boer teaches the method of claim 2 and the apparatus of claim 15, respectively. Galburt further teaches positioning distal sensor 216, proximal set 210 and center of exposure aperture 200 successively along movement axis 204, and selecting sensor spacing as a distance D, and using that distance and scan velocity to establish the time at which a previously measured surface portion reaches the exposure aperture (Figs. 2-3, paras. [0065, 0068, 0070-0071, 0080]. Therefore, it would have been obvious to align one proximal sensor with sensor 216 along axis 204 and position sensor 216 at an equal successive spacing from the proximal sensor, since Galburt’s sensors are positionally configurable, and using a common spacing D along the scan direction permits measurements acquired at successive locations to be registered using the same known distance vs. scan time relationship. As such, in the resulting arrangement, the vector from distal sensor 216 to the aligned proximal sensor 210 is substantially equal to the vector from that proximal sensor to the center of aperture 200, as claimed.
Regarding Claim 14:
Galburt in view of Boer teaches the method of claim 1. Galburt further teaches wherein the proximal sensors and the one or more distal sensors are positioned at substantially the same distance from the stage (Fig. 3 and para. [0070, 0074]: all proximal and distal sensors are mounted to common support plate 100/projection optics above stage 338. Fig. 3 depicts their sensing surfaces at substantially the same stage-facing level).
Conclusion
Any inquiry concerning this communication or earlier communications from the examiner should be directed to JING WANG whose telephone number is (571)272-2504. The examiner can normally be reached M-F 7:30-17:00.
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/JING WANG/Examiner, Art Unit 2881
/WYATT A STOFFA/Primary Examiner, Art Unit 2881
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