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 . This application was filed on 11/09/2022. A Non-Final office action was mailed on 3/14/2025. A Final office action in response to Applicant’s submission of 5/30/2025 was mailed on 8/1/2025. Claims 1-17 were examined.
Continued Examination Under 37 CFR 1.114
A request for continued examination under 37 CFR 1.114, including the fee set forth in 37 CFR 1.17(e), was filed in this application after final rejection. Since this application is eligible for continued examination under 37 CFR 1.114, and the fee set forth in 37 CFR 1.17(e) has been timely paid, the finality of the previous Office action has been withdrawn pursuant to 37 CFR 1.114. Applicant's submission filed on 10/17/2025 has been entered.
Claims 1, 4-6 and 8-17 are being examined.
Response to Arguments and amendments.
This office action addresses the latest amendments related to comparing magnitude of reflected light to detect the tilt of the substrate. Regarding applicant’s argument regarding claim 15, the office action addresses more clearly that the monitoring of substrate surface while scanning across it allows monitoring of zones disposed on the surface and to take any action like controlling etch rate or finishing the process specific to the zones.
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 and 4-6 are rejected under 35 U.S.C. 103 as being unpatentable over of Koyata et al (US 2007/0175863) in view of Takekuma et al (US 2006/0144330) and Chung et al (US 20100236717) or J M Kim (KR 10-2005-0011403) and Lin et al (US 20030218144).
Koyata teaches a liquid etching system (abstract), comprising:
a rotatable spindle to hold a wafer in a face-up orientation (12 Fig 1);
a dispenser arm (27 or 26 Fig 1) movable laterally across the wafer on the support [0035], the dispenser arm supporting a delivery port (26a or 27a) to selectively dispense a liquid onto a portion of a top face of the wafer [0035]; and a
monitoring system (41a or 42a Fig 1) comprising a probe movable laterally across the wafer on the support [0035].
Koyata teaches further that the probe (41a or 42a Fig 1) is secured to and moves with the dispenser arm [0035], that the monitoring system is an optical monitoring system [0038] (note the teaching of a light source and detector [0038]) and a controller configured to receive measurements from the monitoring system (Fig 1, 44).
Koyota teaches a light source and a light detector [0038] but does not explicitly disclose an optical fiber.
Takekuma teaches a substrate processing system (abstract) using liquid just as in an etching system of Koyata and also teaches a rotatable spindle to hold a wafer in a face-up orientation (71 Fig 5 [0069]);
a dispenser arm (81 Fig 5) movable laterally across the wafer on the support [0070], the dispenser arm supporting a delivery port (80 Fig 5) to selectively dispense a liquid onto a portion of a top face of the wafer [0070-0072] and an optical fiber sensor 101 attached to nozzle 85 and the dispenser arm, the optical monitoring system comprises a light source (103 Fig 5), a detector (104 and 105 Fig 5 and [0076] and the optical component (101 and 102 Fig 5) comprises an optical fiber, and
a controller configured to receive measurements from the monitoring system (110 Fig 5) [0077]. Optical monitoring and dispenser arm are attached to a mechanism to move it up/down (Fig 5-81).
It would have been obvious to a person having ordinary skill in the art at the time the invention was filed for Koyata to include an optical fiber as being conventional and convenient.
Koyota in view of Takekuma et al do not explicitly teach that the controller is configured or programmed to determine alignment or the tilt of the wafer using optical system.
It is noted that for etching process to start on a substrate, the substrate has to be loaded on the spindle. Therefore, if the loading is faulty resulting in a misalignment, the following etch process will be a failure. Therefore, the importance of proper alignment could not be overstated. Having to check if the substrate is aligned properly before start of etching would be just common sense. Prior art includes several references to teach detection and in many instances correction of misalignment of the substrate.
For example, Chung et al teach an etching apparatus and states that it is necessary to check positioning abnormality of a substrate before etching process (Para 69). Chung et al teach detection of alignment using a mark or other means like a camera using images (Para 66). Abnormality of loading may also be detected using a gap sensor to detect reduction of light (Para 71)
As another example, J M Kim teaches detection of an alignment state using an optical sensor before etching (See the abstract as below)
A semiconductor etching apparatus and an etching method using the same are provided to check an alignment state of a wafer before etching by using a wafer detecting sensor installed in a shadow ring. A semiconductor etching apparatus includes an electrostatic chuck, a shadow ring, a wafer detecting sensor. The electrostatic chuck (113) is used for fixing a wafer (111). The shadow ring (115) is spaced apart from an edge portion of the wafer. The wafer detecting sensor (123) is installed in the shadow ring to check the existence of the wafer. The wafer detecting sensor is an optical sensor.
Regarding the amendment dated 10/17/2025, detection of tilt using optical means is disclosed in Chung et al and J M Kim. Lin et al however disclose detection of tilt explicitly by using variation of reflected light due to tilt. Lin et al teach that intensity of reflected light reduces due to tilt (Para 34 and Fig 7).
Regarding claims 4 tilt causes reduced magnitude of reflected light (Lin, Fig 7).
Regarding claims 5 the misalignment or tilt is detected from a perpendicular beam in Lin and Koyota.
Regarding claim 6 Kim discloses detection using reflectance from opposite edges as in Fig 2 and 3a and 3b.
Claims 6 and 8-16 are rejected under 35 U.S.C. 103 as being unpatentable over of Koyata et al (US 2007/0175863) in view of Takekuma et al (US 2006/0144330), (Chung et al (US 20100236717) or J M Kim (KR 10-2005-0011403)), Lin et al (US 20030218144), Mauer et al (US 20160126148) and Levy et al (US 20100271621).
Koyota in view of Takekuma et al, Chung and JM Kim as discussed above disclose detection of abnormal loading with optical means. Additionally, Lin et al explicitly disclose detection of tilt from magnitude of reflectance.
They, however do not explicitly disclose detection from
Mauer et al teach a system for wet etching and teach an imaging device (Fig 4, 600) for wafer inspection before and after an etch process (Abstract). Mauer et al disclose a much more versatile wafer inspection system including spectral coherence interferometry (Para 203).
Mauer et al teach a platform 610 for holding a wafer in a horizontal orientation. The platform 610 can move in any number of different directions (x, y, z) and is rotatable. The imaging device 600 includes a non-contact measurement component 620 that measures at least the thickness of the wafer and is configured to detect (measure) and generate a surface profile for the wafer. The non-contact measurement component 620 includes imaging equipment and can be part of an automated device to allow movement of the component 620 with respect to the wafer on the platform 610. For example, the non-contact measurement component 620 can be in the form of an arm or the like that can move in any number of different directions (x, y, z) with respect to the wafer and/or rotate. These facilities allow it to measure properties like wafer thickness, bow, warp, flatness; surface roughness; total thickness variation (TTV), optical inspection pattern recognition; and TSV depth, etc. (Para 68-70).
Therefore, it would be obvious to be able to determine tilt or misalignment of the wafer before processing from the light reflectance in Koyota or Takekuma in view of the teaching of Mauer et al.
Levy et al additionally teach detection and correction of misalignment and tilt after transfer to a stage for processing (Abstract, para 160, 182-183, 234, 243, 337,558 and 563).
Regarding claims 6 additionally, Levy discloses detection of misalignment by reflectance from edge (Fig 2A, 2B and Para 159-160 and 163). It would be obvious that reflectance from edge would vary depending upon the degree of misalignment.
Regarding claims 8-9 wafer type is disclosed to be detected by Mauer et al.
Regarding claim 10 spectrometer for measurements of the substrate are disclose by Mauer et al (para 203) and Levy et al (Fig 11a and description for example para 188)
Regarding claim 11 etching rate measurement is disclosed by Mauer et al (para 07, 13, 81) and Levy et al (Para 441).
Regarding claims 12-15, etch rate control using concentration of etchant or flow rate is disclosed in Mauer et al (Para 81). Regarding 15 additionally, the probe moves across the substrate laterally as shown in Koyota, Takekuma and Mauer disclosing optical monitoring of radial positions belonging to annular zones.
Regarding claim 16 the limitation of housing although Koyata et al do not explicitly disclose a housing but a housing would need to be there with all the dispensing of liquid and needed hardware. Takekuma with all the other things discussed below discloses a housing (CP and wall 70) with a mechanism for rotating a substrate.
Claims 15-17 are also rejected under 35 U.S.C. 103 as being unpatentable over of Koyata et al (US 2007/0175863) in view of Takekuma et al (US 2006/0144330), Mauer et al (US 20160126148), and Mauer et al (US 20140242731).
Koyata, Takekuma et al and Mauer `148 are discussed above as teaching almost all limitations of these claims.
Additionally, Koyata et al teach that the controller may determine where more etching is needed based on thickness and adjust the moving speed (this impacts the dwell time) of the port (supply nozzle 26 or 27) or a flow rate of the etchant to obtain uniform etching of the substrate [0039].
Regarding etch rate control, and etch end point however, Mauer et al `731 disclose these features more explicitly.
Mauer teaches that an optical based end-point detection device (Fig. 5, 500) in a wet etching device (400) [0128] can be used with a controller configured to detect the light signature and compare it to a reference signature for a substrate [0128] and that the light signature (the nature of the light reflected off the substrate surface and collected by the CCD) varies depending on the surface composition [0128].
It would have been obvious to a person having ordinary skill in the art at the time the invention was filed to modify the optical detection system of Koyota to include the controller configured to compare the light signature to reference signatures and to include the CCD light detector of Mauer as the light detector because Mauer teaches that this detector may be used for endpoint detection and teaches the apparatus may be automatically controlled using the controller configured to receive signals and compare them to a reference signal. In this configuration the controller is configured to compare an initial light signature of the surface which is a function of surface composition because Mauer teaches the controller also takes a measurement prior to etching [0125].
3It would have been obvious to a person having ordinary skill in the art at the time the invention was filed to include the aspect of the controller taking a measurement prior to etching because Koyata does not limit when measurements are taken and Mauer teaches this allows for an etching recipe to be chosen based on the substrate [0125-0126]. The ability to take a measurement prior to etching and compare to reference signals which is a function of surface composition results in the ability to determine if the initial surface composition is wrong which would result in the ability to determine if the wafer is an improper type. It is noted that Mauer generated recipe according to substrate. Therefore, it routinely identifies a substrate. Therefore, it would identify a substrate which should not be there.
Mauer teaches the etch rate may be determined [0134] and monitored during etching [0130-0131] and that the system may adjust the recipe [0133] and that adjustments may be made based on the desired etch rate [0125].
It would have been obvious to a person having ordinary skill in the art at the time the invention was made to modify Koyata to include the controller that is configured to adjust dwell time or flow rate based on thickness to be further configured to do so in response to the etch rate compared to a desired etch rate because Koyata teaches these adjustments may be made to control the etching [0039] and Mauer teaches etching rate may be determined and compared to desired etch rates and adjusted when not at the desired values to obtain the desired values [0125]. This represents use of known technique (control and adjustments based on desired etch rate as taught by Mauer) to improve similar devices (controller to provide control of the substrate etching uniformity) in the same way (improved control of the substrate etching uniformity by an automated controller).
It is noted that since Koyota, Takekuma et al and both Mauer`148 and Mauer`731 dis close scanning the surface of the substrate in order to monitor its entire surface they disclose monitoring process parameters for the entire surface. Therefore, monitoring any number of spatially disposed zones on it for process parameters like etch rate and endpoint in order to take process action like controlling etch rate and finish processing at end point of all zones would have been obvious.
Regarding claim 17 therefore monitoring for endpoint on all the zones would have been obvious.
Conclusion
The prior art made of record and not relied upon is considered pertinent to applicant's disclosure.
Saito et al (US 2006/0057804) discloses projection and reception of reflected light by a single probe (Fig 3) in exactly the same way as disclosed in applicant’s specification.
DenBoef (US 20100231889) discloses tilt (Fig 6 and para 42) and misalignment detection (Para 56).
Cai et al (US 20140071457) discloses alignment and tilt detection by optical means.
Morita (US 5853483) teaches a liquid processing apparatus (Col 1, ln 5-20), with light supply to a substrate surface and a collector for collecting light reflected from the surface, the controller may be configured to determine if the wafer is in the correct position or correct type (Col 8, ln 39-47).
Any inquiry concerning this communication or earlier communications from the examiner should be directed to RAM N KACKAR whose telephone number is (571)272-1436. The examiner can normally be reached 09:00 AM-05:00 PM.
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RAM N. KACKAR
Primary Examiner
Art Unit 1716
/RAM N KACKAR/Primary Examiner, Art Unit 1716