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 .
Response to Amendment and Status of Application
This notice is in response to the amendments filed 18 August 2026. Claims 1-4 and 6-22 are pending in the instant application where claims 1-4, 6-11, 13-16, and 18 have been amended.
Response to Arguments
Applicant’s arguments, see Remarks Subsections VII, VIII, and IX, filed 18 August 2026, with respect to independent method claims 19 and 21 have been fully considered and are persuasive. The rejection of claims 19 and 21 have been withdrawn.
Applicant’s arguments with respect to independent claim(s) 1 have been considered but 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 the argument. This is with respect to arguments against the teachings of Liu and Unlu which recite the phase mask acting on light from the sample and not within the illumination path (Remarks Subsections I, II, V, and VI). Claim 1 remains rejected in light of new art, as seen below.
Claim Interpretation
The following is a quotation of 35 U.S.C. 112(f):
(f) Element in Claim for a Combination. – An element in a claim for a combination may be expressed as a means or step for performing a specified function without the recital of structure, material, or acts in support thereof, and such claim shall be construed to cover the corresponding structure, material, or acts described in the specification and equivalents thereof.
The following is a quotation of pre-AIA 35 U.S.C. 112, sixth paragraph:
An element in a claim for a combination may be expressed as a means or step for performing a specified function without the recital of structure, material, or acts in support thereof, and such claim shall be construed to cover the corresponding structure, material, or acts described in the specification and equivalents thereof.
The claims in this application are given their broadest reasonable interpretation using the plain meaning of the claim language in light of the specification as it would be understood by one of ordinary skill in the art. The broadest reasonable interpretation of a claim element (also commonly referred to as a claim limitation) is limited by the description in the specification when 35 U.S.C. 112(f) or pre-AIA 35 U.S.C. 112, sixth paragraph, is invoked.
As explained in MPEP § 2181, subsection I, claim limitations that meet the following three-prong test will be interpreted under 35 U.S.C. 112(f) or pre-AIA 35 U.S.C. 112, sixth paragraph:
(A) the claim limitation uses the term “means” or “step” or a term used as a substitute for “means” that is a generic placeholder (also called a nonce term or a non-structural term having no specific structural meaning) for performing the claimed function;
(B) the term “means” or “step” or the generic placeholder is modified by functional language, typically, but not always linked by the transition word “for” (e.g., “means for”) or another linking word or phrase, such as “configured to” or “so that”; and
(C) the term “means” or “step” or the generic placeholder is not modified by sufficient structure, material, or acts for performing the claimed function.
Use of the word “means” (or “step”) in a claim with functional language creates a rebuttable presumption that the claim limitation is to be treated in accordance with 35 U.S.C. 112(f) or pre-AIA 35 U.S.C. 112, sixth paragraph. The presumption that the claim limitation is interpreted under 35 U.S.C. 112(f) or pre-AIA 35 U.S.C. 112, sixth paragraph, is rebutted when the claim limitation recites sufficient structure, material, or acts to entirely perform the recited function.
Absence of the word “means” (or “step”) in a claim creates a rebuttable presumption that the claim limitation is not to be treated in accordance with 35 U.S.C. 112(f) or pre-AIA 35 U.S.C. 112, sixth paragraph. The presumption that the claim limitation is not interpreted under 35 U.S.C. 112(f) or pre-AIA 35 U.S.C. 112, sixth paragraph, is rebutted when the claim limitation recites function without reciting sufficient structure, material or acts to entirely perform the recited function.
Claim limitations in this application that use the word “means” (or “step”) are being interpreted under 35 U.S.C. 112(f) or pre-AIA 35 U.S.C. 112, sixth paragraph, except as otherwise indicated in an Office action. Conversely, claim limitations in this application that do not use the word “means” (or “step”) are not being interpreted under 35 U.S.C. 112(f) or pre-AIA 35 U.S.C. 112, sixth paragraph, except as otherwise indicated in an Office action.
This application includes one or more claim limitations that do not use the word “means,” but are nonetheless being interpreted under 35 U.S.C. 112(f) or pre-AIA 35 U.S.C. 112, sixth paragraph, because the claim limitation(s) uses a generic placeholder that is coupled with functional language without reciting sufficient structure to perform the recited function and the generic placeholder is not preceded by a structural modifier.
Because this/these claim limitation(s) is/are being interpreted under 35 U.S.C. 112(f) or pre-AIA 35 U.S.C. 112, sixth paragraph, it/they is/are being interpreted to cover the corresponding structure described in the specification as performing the claimed function, and equivalents thereof.
If applicant does not intend to have this/these limitation(s) interpreted under 35 U.S.C. 112(f) or pre-AIA 35 U.S.C. 112, sixth paragraph, applicant may: (1) amend the claim limitation(s) to avoid it/them being interpreted under 35 U.S.C. 112(f) or pre-AIA 35 U.S.C. 112, sixth paragraph (e.g., by reciting sufficient structure to perform the claimed function); or (2) present a sufficient showing that the claim limitation(s) recite(s) sufficient structure to perform the claimed function so as to avoid it/them being interpreted under 35 U.S.C. 112(f) or pre-AIA 35 U.S.C. 112, sixth paragraph.
Regarding claim 1, the claim recites the limitations “illumination subsystem”, “collection subsystem”, and light detection subsystem” which use the generic placeholder “subsystem” that are coupled with functional language without reciting sufficient structure to perform the recited function and the generic placeholder is not preceded by a structural modifier.
Accordingly, “illumination subsystem” is interpreted under 35 U.S.C. 112(f) as corresponding to a light source (or sources) 204 configured to generate incident light 206 (applicant’s specification [0024]), where the light source(s) may include a broadband lamp, narrow-band laser, light-emitting diode, semiconductor laser, gas laser, pulsed laser, continuous wave laser, etc. (applicant’s specification [0025]), and comprise an objective, telescope optics, 218, relay optics, etc. (applicant’s specification [0028], and any equivalents thereof.
The limitation “collection subsystem” is interpreted under 35 U.S.C. 112(f) as corresponding to an objective, telescope optics, relay optics; any number of lens types (applicant’s specification [0025]), one or more directional filters, and any equivalents thereof.
The limitation “light detection subsystem” is interpreted under 35 U.S.C. 112(f) as corresponding to a relay optics comprised of lenses, mirrors, waveguides, etc., light detectors including complementary metal-oxide-semiconductor (CMOS) image sensors, charge coupled devices (CCDs), hybrid CMOS-CCD image sensors, photomultiplier tubes (e.g., an array of photocathode-based pixels), photodiodes, phototransistors, or any other suitable photon detectors (applicant’s specification [0060]), and any equivalents thereof
Regarding claim 17, the claim recites the limitation “processing device” which uses the generic placeholder “device” that is coupled with functional language without reciting sufficient structure to perform the recited function and the generic placeholder is not preceded by a structural modifier.
Accordingly, the limitation “processing device” is interpreted under 35 U.S.C. 112(f) as corresponding to central processing units (CPUs), application-specific integrated circuits (ASICs), field programmable gate arrays (FPGAs), digital signal processors (DSPs), and network processors (applicant’s specification [0057]) and any equivalents thereof.
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.
This application currently names joint inventors. In considering patentability of the claims the examiner presumes that the subject matter of the various claims was commonly owned as of the effective filing date of the claimed invention(s) absent any evidence to the contrary. Applicant is advised of the obligation under 37 CFR 1.56 to point out the inventor and effective filing dates of each claim that was not commonly owned as of the effective filing date of the later invention in order for the examiner to consider the applicability of 35 U.S.C. 102(b)(2)(C) for any potential 35 U.S.C. 102(a)(2) prior art against the later invention
Claims 1-3, 6-8, 11-12, and 16-18 are rejected under 35 U.S.C. 103 as being unpatentable over US 2022/0268710 A1 by Xuefeng Liu et al. (herein after “Liu”) in view of US 2023/0093989 A1 by Sumeet Mahajan et al. (herein after “Mahajan”).
Regarding claim 1, Liu discloses a sample inspection system (Liu [0063] and fig. 1B disclose a detection device which captures an image of a sample 106 [sample inspection]), comprising:
an illumination subsystem to generate a light incident on a sample (Liu [0053] and fig. 1B discloses an illumination source 112 which directs a beam 114 to sample 106);
a phase mask positioned within an optical path of light (Liu fig. 2 shows a phase mask 202; fig. 1B and [0064] disclose that a continuous degenerate elliptical retarder 104 (CDER – see [0014]); [0108] discloses that the CDER 104 comprises the phase mask 202 (though not shown in the figs.) and is within an optical path of light), the phase mask comprising:
a first region to engage a first potion of light interacting with the phase mask (Liu [0072] and fig. 2 disclose the phase mask 202 with a first segment 204 [first region]; fig. 1B shows the CDER 104 comprising phase mask 202 – including the first portion 204), and
a second region to engage a second portion of the light interacting with the phase mask and impart a phase shift to the second portion relative to the first portion (Liu [0072] and fig. 2 disclose the phase mask 202 has a second segment 206 - the second region interacts with at least a second portion of light i.e. the portion of light which hasn’t engaged with the first portion; the segment 204 [first portion] is formed from a half-wave plate and the segment 206 [second portion] does not rotate the polarization of the light, therefore the second region phase-shifts the second portion relative to the first portion; one of ordinary skill recognizes that waveplates are used to phase shift light (fig. 2 shows a phase shift in the exponential function eiπ); examiner notes that either region 204 or 206 may be termed as the “first region” or “second region” – the claim is satisfied so long as there is a relative phase-shift between the light exiting the first region and the second region);
a collection subsystem comprising one or more optical elements to collect a light generated upon interaction of the incident light with the sample (Liu [0066] discloses any number of beam-conditioning elements to direct or modify the sample light 122 including lenses, filters, apertures, polarizers, phase masks, etc.; any combination of beam-conditioning elements read as the “collection subsystem”); and
a light detection subsystem configured to detect the collected light and generate one or more signals representative of one or more characteristics of the sample (Liu [0063] and fig. 1B discloses at least one detector 110 which captures light configured to capture at least a portion of the sample light 122; fig. 1B and [0051] shows an additional detector 110; [0063] discloses that the detectors 110 may be multi-pixel detector to capture an image of the sample [characteristics of the sample]; the detector 110 may also be a spectroscopic detector to identify wavelengths of the sample light 122 [characteristics of the sample based on wavelengths of light after interacting with the sample]; any and all detectors 110 and equivalent read as the “light detection system”).
Liu is silent to the illumination subsystem comprising a phase mask positioned within an optical path of the light incident on the sample, and
wherein the phase shift causes a combined electric field of the light incident on the sample, formed using the first portion and the second portion, to have a component perpendicular to a surface of the sample.
However, Mahajan does address this limitation. Liu and Mahajan are considered to be analogous to the present invention because they are sample inspection systems detecting scattered light from the sample surface.
Mahajan discloses “the illumination subsystem comprising a phase mask positioned within an optical path of the light incident on the sample” (Mahajan [0066] and fig. 3 disclose an embodiment of imaging apparatus 200 comprising one or more illumination devices 200; [0069] the illumination device comprises a beam shaping element, such as an airy phase mask before being directed to sample 300 for shaping beam into a desired phase profile [illumination subsystem comprising a phase mask within an optical path of the light incident on the sample]), and
“wherein the phase shift causes a combined electric field of the light incident on the sample, formed using the first portion and the second portion, to have a component perpendicular to a surface of the sample” (Mahajan [0019] discloses that incident light of light to the sample may be perpendicular to a surface of the sample, and in light of the beam shaping by the phase mask within [0069], the phase shift imparted by phase mask generates the electric field of light incident on the sample to have the component perpendicular a surface of the sample; while the claim recites “combined electric field”, the requirement is not that the combined electric field is perpendicular to the surface, just that a component of the combined electric field is perpendicular to the surface).
Therefore, it would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to modify Liu to incorporate the illumination subsystem comprising a phase mask positioned within an optical path of the light incident on the sample, and wherein the phase shift causes a combined electric field of the light incident on the sample, formed using the first portion and the second portion, to have a component perpendicular to a surface of the sample as suggested by Mahajan for the advantage of further obtaining material specific identifiable information from the sample based on the incident light having a desired polarization/phase profile (Mahajan [0019]-[0020]).
Regarding claim 2, Liu when modified by Mahajan discloses the sample inspection system of claim 1, and Liu further teaches the system wherein the second region of the phase mask is to phase-shift the second portion of the light relative to the first portion by a phase shift that is between λ/4 and 3λ/4, wherein λ is a wavelength of the incident light (Liu [0072] discloses that the segment 204 is formed from a half-wave plate, thereby introducing a phase shift of π; the wavelength of the light incident on the first phase mask 202 will be the same for the first and second portions – a phase shift of 2π results in one complete cycle for the wavelength of light incident; a phase shift of π results in a half cycle [i.e. shifting the phase of the incident light by λ/2]).
Regarding claim 3, Liu when modified by Mahajan discloses the sample inspection system of claim 1, and Liu further teaches the system wherein the second region of the first phase mask is to phase-shift the second portion of the light relative to the first portion by half a wavelength of the incident light (Liu [0072] discloses that the segment 204 is formed from a half-wave plate, thereby introducing a phase shift of π; the wavelength of the light incident on the first phase mask 202 will be the same for the first and second portions – a phase shift of 2π results in one complete cycle for the wavelength of light incident; a phase shift of π results in a half cycle [i.e. shifting the phase of the incident light by λ/2]).
Regarding claim 6, Liu when modified by Mahajan discloses the sample inspection system of claim 1, and Liu further teaches the system wherein the first region of the phase mask comprises air or a first material of a first thickness, and wherein the second region of the phase mask comprises at least one of: a second material, or the first material of a second thickness (Liu [0072] discloses that the segment 204 [first region of the first phase mask] is formed from a half-wave plate [first material], and that the segment 206 [second region] comprises a compensating plate having the same thickness as the half-wave plate [the first material has a first thickness, and the second region comprises the first material of a second thickness]; in this case, the first and second thickness are approximately the same)
Regarding claim 7, Liu when modified by Mahajan discloses the sample inspection system of claim 1, and Liu further teaches the system wherein the first region of the phase mask comprises a first material, and wherein the second region comprises the first material, wherein the first material comprises a polarizing material (Liu [0072] discloses that the segment 204 [first region] is formed with a half-wave plate [constructed from a first material]; the half-wave plate is known in the art to rotate the polarization [i.e. first material comprises a polarizing material]; the segment 206 [second region] is constructed from same material as the half-wave plate)
Liu does not explicitly disclose the sample inspection system of claim 1, wherein the second region of the phase mask comprises a second material.
However, Liu does suggest this limitation.
Liu discloses or renders obvious the sample inspection system of claim 1, “wherein the second region of the phase mask comprises a second material” (Liu [0075] discloses that the phase mask 202 may include any number of segments (i.e. beyond a first and second region) formed from any combination of materials in any pattern, therefore, the second region comprising a second material is covered by Liu where the second region can be constructed by a first and second material).
Therefore, it would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to modify Liu and incorporate wherein the second region of the phase mask comprises a second material as suggested by Liu for the advantage of achieving the ability to selectively adjust the phase of regions within the phase mask to reshape the point spread function (PSF) of an image of the sample (i.e. providing a tight PSF for high resolution for images) (Liu [0075]).
Regarding claim 8, Liu when modified by Mahajan discloses the sample inspection system of claim 1, and Liu further teaches the system wherein at least one of the first region of the phase mask or the second region of the phase mask comprises one or more birefringent materials (Liu [0128] and fig. 1B discloses that the polarization-controlling optical elements [which form the CDER 104 in fig. 1B, first phase mask] comprises a segmented waveplate with multiple segments [i.e. first and second regions], which may be formed by birefringent materials).
Regarding claim 11, Liu when modified by Mahajan discloses the sample inspection system of claim 1, and Liu further teaches the system further comprising a polarizing optical element (Liu [0050] fig. 1B discloses a linear polarizer 108 [polarizing optical element]) to:
polarize, prior to interaction with the phase mask, the light interacting with the phase mask, or
polarize, after interaction with the phase mask, at least one of the first portion of the light or the second portion of the light (Liu fig. 1B shows the linear polarizer 108 appearing after the phase mask 202 in the CDER 104; [0051] discloses that the linear polarizer 108 is formed as a polarizing beam splitter [polarize after interaction with the first phase mask]; the first limitation is not addressed due to the “or” statement).
Regarding claim 12, Liu when modified by Mahajan discloses the sample inspection system of claim 11, and Liu further teaches the system wherein the polarizing optical element comprises at least one of: a linear polarizer (Liu [0050] discloses that the polarizer 108 is a linear polarizer; the remaining choices for the polarizing optical element are not considered here due to the “or” statement).
Regarding claim 16, Liu when modified by Mahajan discloses the sample inspection of claim 1, and Liu further teaches the system wherein each of the first region and the second region of the phase mask comprises a plurality of spatially separated portions (Liu [0075] discloses that the phase mask may include any number of segments formed from any combination of materials in any pattern across the pupil plane 130 shown in fig. 1B; therefore the first and second regions may have any number of segments along the pupil plane 130 – since any number of segments in any pattern are across the pupil plane 130, the first region and second region comprise a plurality of spatially separated portions)
Regarding claim 17, Liu when modified by Mahajan discloses the sample inspection system of claim 1, and Liu further teaches the system further comprising: a processing device configured to determine, using the one or more signals, the one or more characteristics of the sample (Liu [0121] discloses that the particle detection system 100 includes a controller 134 which has one or more processors 136; the controller 134 receives, analyzes, and/or processes data from the detector 110 [i.e. associated with the image of the sample] – receiving/analyzing/processing data from the detector related to an image of the sample is equivalent to determining the one or more characteristics of the sample; claim 1 recites the characteristics of the sample related to capturing an image and identify wavelengths of the sample light)
Regarding claim 18, Liu when modified by Mahajan discloses the sample inspection system of claim 1, and Liu further teaches the system wherein the second region of the phase mask is to rotate polarization of the second portion of the light relative to the first portion of the light (Liu [0072] and fig. 2 discloses first phase mask 202 which is comprised of first region 204 and 206 where the first region 204 is comprised of the half wave plate; the half-wave plate rotates the polarization of the first portion of the light relative to the second portion – it is also true to say the polarization of the second portion of the light is rotated relative to the first portion of the light, depending on one’s frame of reference; also, as noted in claim 1, either region 204 or 206 may be termed as the first region or the second region, so that the segment 204 in this instance may be termed as the “second region” and fulfills the relative polarization rotation between the regions 204 and 206).
Claims 4 and 13-14 are rejected under 35 U.S.C. 103 as being unpatentable over Liu in view of Mahajan, and further in view of US 2019/0026885 A1 by David Gready et al. (herein after “Gready”).
Regarding claim 4, Liu when modified by Mahajan discloses the sample inspection system of claim 1 but is silent to the system further comprising an additional phase mask positioned within an optical path of a scattered part of the collected light.
However, Gready does address this limitation. Liu, Mahajan, and Gready are considered to be analogous to the present invention because they are sample inspection systems detecting scattered light from the sample surface.
Gready discloses the sample inspection system of claim 1, “further comprising an additional phase mask positioned within an optical path of a scattered part of the collected light” (Gready title disclose an image based metrology monitoring process for [0032] a sample 106 on a sample stage 116; [0038] and fig. 1 disclose illumination optical components 112 and collection optical components 124 where each of the components may include phase masks at pupil planes; a phase mask within illumination optical components 112 at the illumination pupil plane is the phase mask of claim 1 and the additional phase mask within collection optical components 124 at the collection pupil plane is the additional phase mask; [0033] recites that the detector 118 shown in fig. 1 receives radiation scattered from the sample 106 [additional phase mask positioned within scattered part of collected light]).
Therefore, it would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to modify Liu and Mahajan to incorporate an additional phase mask positioned within an optical path of a scattered part of the collected light as suggested by Gready for the advantage of modifying the phase of the collected light, thereby imaging the sample 106 using a selected/desired imaging technique (Gready [0038]).
Regarding claim 13, Liu when modified by Mahajan discloses the sample inspection system of claim 1 but is silent to the system wherein the phase mask is positioned at a pupil plane of the illumination subsystem.
However, Gready does address this limitation.
Gready discloses the sample inspection system of claim 1 “wherein the phase mask is positioned at a pupil plane of the illumination subsystem” (Gready [0038], as disclosed within claim 4 above, the illumination optical components 112 comprise at least one phase mask positioned at an illumination pupil plane of the imaging system [phase mask positioned at pupil plane of illumination subsystem]).
Therefore, it would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to modify Liu in view of Mahajan to incorporate wherein the phase mask is positioned at a pupil plane of the illumination subsystem as suggested by Gready for the advantage of modifying the phase of the entire illumination beam for use with a selected imaging technique – were the phase mask not at the pupil plane of the illumination subsystem, the phase of the illumination light may be unequally altering.
Regarding claim 14, Liu when modified by Mahajan discloses the sample inspection system of claim 1 but is silent to the system wherein the phase mask attenuates at least a fraction of (i) the first portion of the light or (ii) the second portion of the light.
However, Gready does address this limitation.
Gready discloses the sample inspection system of claim 1, “wherein the phase mask attenuates at least a fraction of (i) the first portion of the light or (ii) the second portion of the light” (Gready [0038] and claims 4 and 13 above has disclosed the illumination optical components 112 which comprise at least one of a phase mask, filters, apertures, etc. to modify the intensity and/or the phase of illumination beam 104; in the case of a desired modification to both phase and intensity, it would be obvious to combine a phase mask with an intensity filter).
Therefore, it would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to modify Liu in view of Mahajan to incorporate wherein the phase mask attenuates at least a fraction of (i) the first portion of the light or (ii) the second portion of the light as suggested by Gready for the advantage of modifying both the phase and intensity of the illumination light, thereby imaging the sample 106 using a selected/desired imaging technique (Gready [0038]).
Claims 9 and 10 are rejected under 35 U.S.C. 103 as being unpatentable over Liu in view of Mahajan, and further in view of US 2013/0141715 A1 by Yuta Urano et al. (“Urano”).
Regarding claim 9, Liu when modified by Mahajan discloses the sample inspection system of claim 1 but is silent to the system wherein the phase mask comprises at least one of: an acoustic modulator supporting a sound wave that causes the first portion of the light and the second portion of light to form the incident light that dynamically scans the sample, one or more segments made of a liquid crystal material, or a deformable mirror.
However, Urano does address this limitation. Liu, Mahajan, and Urano are considered to be analogous to the present invention because they are in the same field of light-based sample inspection systems.
Urano discloses the sample inspection system of claim 1, “wherein the phase mask comprises at least one of: an acoustic modulator supporting a sound wave that causes the first portion of the light and the second portion of light to form the incident light that dynamically scans the sample, one or more segments made of a liquid crystal material, or a deformable mirror” (Urano [0143] and fig. 18 discloses a polarization modulation element 155 [analogous to the first phase mask of Liu] where the modulation element 155 comprises a liquid crystal element [one or more segments made of a liquid crystal material]).
Therefore, it would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to modify Liu in view of Unlu to incorporate wherein the phase mask comprises one or more segments made of a liquid crystal material as suggested by Urano for the advantage of generating polarization states without the loss of illumination energy (Urano [0134]).
Regarding claim 10, Liu when modified by Mahajan discloses the sample inspection system of claim 1, and Liu further teaches “wherein at least one of (i) a first thickness of the first region of the phase mask or (ii) a first voltage applied to the first region of the phase mask is different from a corresponding one of (i) a second thickness of the second region of the phase mask or (ii) a second voltage applied to the second region of the phase mask” (Liu [0086] discloses that the CDER 104 may be formed from two polarization rotators 402; the CDER 104 is shown along the pupil plane 130 in fig. 1B; [0099] discloses that the polarization rotator 402 includes a phase compensator 410 which has a spatially-varying thickness across the pupil plane 130 [along which the phase mask 202 sits as well; given that the CDER is formed by a phase compensator 410 that has a spatially varying thickness across the pupil plane, one of ordinary skill in the art would consider obvious the first and second regions of the phase mask having thicknesses that are different from one another).
Liu when modified by Unlu is silent to the sample inspection system of claim 1, wherein the phase mask comprises an electro-optic modulator.
However, Urano does address this limitation.
Urano discloses the sample inspection system of claim 1, “wherein the phase mask comprises an electro-optic modulator” (Urano [0134] and fig. 18 discloses the polarization modulation element 155 [equivalent to the phase mask of Liu] where the modulation element 155 comprises an electro-optic modulator).
Therefore, it would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to modify Liu in view of Unlu to incorporate wherein the phase mask comprises an electro-optic modulator as suggested by Urano for the advantage of generating polarization states without the loss of illumination energy (Urano [0134]).
Claim 15 is rejected under 35 U.S.C. 103 as being unpatentable over Liu in view of Unlu, and further in view of US 2017/0276613 A1 by Sheng Liu and Guoheng Zhao (“Zhao”).
Regarding claim 15, Liu when modified by Mahajan discloses the sample inspection system of claim 1 but is silent to the system further comprising: an actuator configured to perform at least one of:
repositioning the phase mask,
replacement of the phase mask with a different phase mask, or
removal of the phase mask from the optical path of the light incident on the sample.
However, Zhao does address this limitation. Liu, Mahajan, and Zhao are considered to be analogous to the present invention because they are in the same field of light-based sample inspection systems.
Zhao discloses the sample inspection system of claim 1, “further comprising: an actuator configured to perform at least one of:
“repositioning the phase mask” (Zhao fig. 7 shows a similar sample inspection device to that of Liu with a plurality of components arranged along a collection path up to an image sensor 718 ([0091]); [0126] discloses motor mechanisms [i.e. a band actuator and motor], where these motor mechanisms may be configured to move other components of the inspection system including collection mirrors, apertures, polarizers, analyzers, waveplates, etc.; the first phase mask 202 of Liu is comprised of a half-wave plate, and therefore the actuator of Zhao covers repositioning the first phase mask; the remaining limitations are not considered due to the “at least one of” statement).
Therefore, it would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to modify Liu in view of Mahajan to incorporate an actuator configured to reposition the phase mask as suggested by Zhao for the advantage of optimizing the position of the first phase mask as needed for different iterations of the illumination and collection subsystems.
Allowable Subject Matter
Claims 19-22 are allowed.
The following is an examiner’s statement of reasons for allowance:
The prior art of record neither anticipates nor renders obvious the claimed subject matter of the instant application as a whole either taken alone or in combination. In particular, a thorough search for pertinent prior art did not locate any prior art that discloses or suggests all limitations of the invention disclosed in the instant application.
Regarding claim 19, the concept of “a method to perform an optical inspection of a sample, the method comprising:
generating a source light;
directing the source light to a first phase mask, wherein the first phase mask comprises:
a first region interacting with a first portion of the light, and
a second region (i) interacting with a second portion of the light and (ii) phase-shifting the second portion of the light relative to the first portion of the light to facilitate constructive interference of the first portion of the light with the second portion of the light along a direction of resonant polarization of one or more defects of the sample, and
a filter separating the first region from the second region and reducing intensity of a third portion of the source light;
illuminating the sample using the source light;
collecting a light generated upon interaction of the source light with the sample;
directing the collected light to a light detection sensor to generate one or more signals; and
determining, using the one or more signals, one or more characteristics of the sample” is considered to define patentable subject matter over the prior art of record.
The closest prior art is generally regarded to be Liu in view of US 2019/0162647 A1 by Selim M. Unlu et al. (herein after “Unlu”), which recites a method to perform an optical inspection of a sample (Liu [0039] discloses methods for particle detection via imaging of a sample [optical inspection of a sample]), the method comprising:
generating a source light (Liu [0053] and fig. 1B shows an illumination source 112 which generates an illumination beam 114 [generating a source light]);
directing light to a first phase mask (Liu fig. 2 shows a phase mask 202; fig. 1B shows light directed to a continuous degenerate elliptical retarder 104 (CDER – see [0014]); [0108] discloses that the CDER 104 comprises the phase mask 202; light is seen being directed through the first phase mask within fig. 1B), wherein the first phase mask comprises:
a first region interacting with a first portion of the light (Liu [0072] and fig. 2 disclose the phase mask 202 with a first segment 204 [first region]; fig. 1B shows the CDER 104 comprising phase mask 202 – including the first portion 204 – interacting with light as the light is directed through the phase mask 202 [first region interacts with a first portion of the light]), and
a second region (i) interacting with a second portion of the light and (ii) phase-shifting the second portion of the light relative to the first portion of the light (Liu [0072] and fig. 2 disclose the phase mask 202 has a second segment 206; as above, the phase mask 202 – including the second portion 206 – is shown interacting with light as the light is directed through the first phase mask 202; the segment 204 [first portion] is formed from a half-wave plate and the segment 206 [second portion] does not rotate the polarization of the light, therefore the second region phase-shifts the second portion relative to the first portion; one of ordinary skill recognizes that waveplates are used to phase shift light (fig. 2 shows a phase shift in the exponential function eiπ); examiner notes that either region 204 or 206 may be termed as the “first region” or “second region” – the claim is satisfied so long as there is a relative phase-shift between the light exiting the first region and the second region, which has been shown), and
a filter separating the first region from the second region and reducing intensity of a third portion of the source light (Unlu [0012] discloses that the phase mask comprised of two or more concentric regions where one of the regions has a transmittivity or reflectivity greater or less than the other region(s); where the transmittivity of at least one region vs the other region is different, the region with the lesser transmittivity is considered as a filter which reduces the intensity of transmitted light [reducing intensity of a third portion of light]);
illuminating the sample using the source light (Liu [0053] and fig. 1B show the illumination beam 114 directed along illumination pathway 116 to the sample);
collecting a light generated upon interaction of the source light with the sample (Liu [0061] discloses an objective lens 126 which collects at least a portion of the sample light 122 [the sample light 122 being the light generated upon interaction of the source light with the sample]);
directing the collected light to a light detection sensor to generate one or more signals (Liu [0063] and fig. 1B discloses at least one detector 110; the light after being incident on the sample is collected by objective lens 126, and directed to the detector; the detector 110 may be a multi-pixel detector [generate one or more signals]); and
determining, using the one or more signals, one or more characteristics of the sample (Liu [0063] discloses that the detectors 110 are multi-pixel detectors as indicated above, and are used to capture an image of the sample [characteristics of the sample]; the detector 110 may also be a spectroscopic detector to identify wavelengths of the sample light 122 [characteristics of the sample based on wavelengths of light after interacting with the sample]).
The combination of Liu and Unlu is silent to the second region of the phase mask interacting with the source light to facilitate constructive interference of the first portion of the light with the second portion of the light along a direction of resonant polarization of one or more defects of the sample. Applicant’s arguments with respect to this limitation and examiner’s previous assertion that “there is no step or structure linked to the facilitation of constructive interference that clearly distinguishes over Liu (Remarks Section VII.) is persuasive. Therefore, the rejection of claim 19 is withdrawn.
Claim 20 is allowable due to its dependence on the allowable subject matter recited within claim 19 above.
Regarding claim 21, the concept of “a method to perform an optical inspection of a sample, the method comprising:
generating a source light;
illuminating the sample using the source light;
collecting light generated upon interaction of the source light with the sample;
directing at least a part of the collected light to a plurality of phase masks wherein each phase mask of the plurality of phase masks comprises at least:
a first region to engage a first portion of light interacting with a respective phase mask of the plurality of phase masks, and
a second region to (i) engage a second portion of the light interacting with the respective phase mask and (ii) phase-shift the second portion of the collected light relative to the first portion of the collected light;
wherein the plurality of phases masks comprises:
a first phase mask within an optical path of the collected light, wherein positioning of the first phase mask facilitates constructive interference of the collected light along a direction of resonant polarization of one or more defects of the sample, and
a second phase mask within an optical path of the collected light, wherein positioning of the second phase mask facilitates constructive interference of the collected light generated by the resonant polarization of the one or more defects of the sample;
directing the collected light to a light detection sensor to generate one or more signals; and
determining, using the one or more signals, one or more characteristics of the sample” is considered to define patentable subject matter over the prior art of record.
The closest prior art is generally regarded to be Liu in view of Unlu, which discloses a method to perform an optical inspection of a sample (Liu [0039] discloses methods for particle detection via imaging of a sample [optical inspection of a sample]), the method comprising:
generating a source light (Liu [0053] and fig. 1B shows an illumination source 112 which generates an illumination beam 114 [generating a source light]);
illuminating the sample using the source light (Liu [0053] and fig. 1B show the illumination beam 114 directed along illumination pathway 116 to the sample);
collecting light generated upon interaction of the source light with the sample (Liu [0061] discloses a collection pathway 124 where an objective lens 126 collects at least a portion of the sample light 122 [the sample light 122 being light generated upon interaction of the source light with the sample]);
directing at least a part of the collected light to a phase mask (Liu fig. 2 shows a phase mask 202; fig. 1B shows light collected by the objective lens 126 feeding into a [0064] continuous degenerate elliptical retarder 104 (CDER – see [0014]); [0108] discloses that the CDER 104 comprises the phase mask 202 (though not shown in the figs.), and therefore the phase mask 202 is within the collection pathway 124 [positioned to interact with the collected light]), [or a plurality of phase masks] (Unlu fig. 2 and [0043]-[0044] disclose a multi arm detection system comprising an illumination arm from light source 222 and two detectors 232, 242; there are a plurality of masks 224, 236, and 246 [plurality of phase masks]; Unlu [0012] discloses that phase mask(s) are used for controlling the phase of the illuminating and reflected light with two or more concentric regions, i.e. a bullseye shape top left of fig. 2 [the phase mask of the plurality of phase masks has a first region and a second region via the at least two concentric regions – [0012] recites such that masks at both the illuminating arm and reflecting arms have the two or more concentric regions (i.e. each mask 224, 236, and 246 share the concentric region features)), wherein each phase mask of the plurality of phase masks comprises at least:
a first region to engage a first portion of light interacting with a respective phase mask of the plurality of phase masks (Liu [0072] and fig. 2 disclose the phase mask 202 with a first segment 204 [first region]; fig. 1B shows the CDER 104 comprising phase mask 202 – including the first portion 204 – is disposed along the collection pathway 124 [the first region interacts with at least a first portion of light]; here, “a respective phase mask” is considered as the phase mask 202 itself – the light is interacting with the phase mask itself), and a second region to (i) engage a second portion of the light interacting with the respective phase mask of the plurality of phase masks and (ii) phase shift the second portion relative to the first portion of the collected light (Liu [0072] and fig. 2 disclose the phase mask 202 has a second segment 206; as above, the phase mask 202 (including the second portion) is disposed along collection pathway 124 [the second region interacts with at least a second portion of light i.e. the portion of light which hasn’t engaged with the first portion]; the segment 204 [first portion] is formed from a half-wave plate and the segment 206 [second portion] does not rotate the polarization of the light, therefore the second region phase-shifts the second portion relative to the first portion; one of ordinary skill recognizes that waveplates are used to phase shift light (fig. 2 shows a phase shift in the exponential function eiπ); examiner notes that either region 204 or 206 may be termed as the “first region” or “second region” – the claim is satisfied so long as there is a relative phase-shift between the light exiting the first region and the second region, which has been shown; as with the preceding limitation, “the respective phase mask” is considered as the phase mask 202 itself – the light is interacting with the phase mask itself);
wherein the plurality of phase masks comprises:
a first phase mask within an optical path of the collected light (Unlu [0046] discloses a plurality of phase masks where masks 236 and 246 are positioned along collection arms and are positioned to capture components of reflected [and scattered] light from the sample 100 – the “second phase mask” is addressed via Liu below); and
a second phase mask within an optical path of the collected light (Liu [0070] discloses a modification of the phase of the sample light 122 across the pupil plane 130 (i.e. across the CDER 104 containing phase mask 202, see fig. 1B));
directing the collected light to a light detection sensor to generate one or more signals (Liu [0063] and fig. 1B discloses at least one detector 110 which appears on the side of the collection pathway 124 after interaction with the CDER 104; the detector 110 may be a multi-pixel detector [generate one or more signals]); and
determining, using the one or more signals, one or more characteristics of the sample (Liu [0063] discloses that the detectors 110 are multi-pixel detectors as indicated above, and are used to capture an image of the sample [characteristics of the sample]; the detector 110 may also be a spectroscopic detector to identify wavelengths of the sample light 122 [characteristics of the sample based on wavelengths of light after interacting with the sample]).
The combination of Liu and Unlu is silent to wherein positioning of the first phase mask facilitates constructive interference of the collected light along a direction of resonant polarization of one or more defects of the sample and wherein positioning of the second phase mask facilitates constructive interference of the collected light generated by the resonant polarization of the one or more defects of the sample.
As recited within the reasons for allowance for claim 19, applicant’s arguments with respect to this limitation and examiner’s previous assertion that “there is no step or structure linked to the facilitation of constructive interference that clearly distinguishes over Liu (Remarks Section VII.) is persuasive. Therefore, the rejection of claim 21 is withdrawn.
Claim 22 is allowable due to its dependence on the allowable subject matter recited within claim 21 above.
Any comments considered necessary by applicant must be submitted no later than the payment of the issue fee and, to avoid processing delays, should preferably accompany the issue fee. Such submissions should be clearly labeled “Comments on Statement of Reasons for Allowance.”
Documents Considered but not Relied Upon
The following document(s) were considered but not relied up on for the rejection set forth in this action:
US 2025/0191170 A1 by Iftach Galon et al. which recites the placement of a phase mask within both illumination and collection arms of a sample inspection apparatus, analogous to the claimed invention but does not recite the facilitation of constructive interference along a direction of resonant polarization due to the placement of the phase masks.
US 2015/0355098 A1 by David Hsieh et al. which recites the placement of a phase mask within an illumination arm of a sample inspection apparatus, analogous to the configuration of amended claim 1.
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.
Any inquiry concerning this communication or earlier communications from the examiner should be directed to JOSHUA M CARLSON whose telephone number is (571)270-0065. The examiner can normally be reached Mon-Fri. 8:00AM - 5:00PM.
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If attempts to reach the examiner by telephone are unsuccessful, the examiner’s supervisor, Tarifur R Chowdhury can be reached at (571) 272-2287. The fax phone number for the organization where this application or proceeding is assigned is 571-273-8300.
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/JOSHUA M CARLSON/Examiner, Art Unit 2877
/TARIFUR R CHOWDHURY/Supervisory Patent Examiner, Art Unit 2877
