DETAILED ACTION
Priority Claim
Receipt is acknowledged of certified copies of papers required by 37 CFR 1.55.
IDS
All references provided in the IDS dated 11/14/2023 and 05/28/2024 have been considered.
Election/Restrictions
Applicant’s election without traverse of Species A (Claims 1-20) in the reply filed on 04/13/2026 is acknowledged.
Specification
The disclosure is objected to because of the following informalities: claimed features not mentioned in the specification, missing/inconsistent reference numerals, lack of clarity.
There are no reference numerals provided for “a first mark” and “a second mark”. As these are claimed elements, a reference numeral should be provided.
There are no reference numerals provided for “a first light” and “a second light”. As these are claimed elements, a reference numeral should be provided.
In the specification, for example ¶ [0075], reference numeral 32 and 34 is used for ‘diffracted light beams’, reference numeral 32 is used for ‘first-order light beam’ and reference numeral 34 is used for ‘first-order light beam’. It is unclear if 32 and 34 are the same light beam or diffracted light beams.
Drawings
The drawings are objected to under 37 CFR 1.83(a). The drawings must show every feature of the invention specified in the claims. Therefore, the “first mark”, “second mark” must be shown or the feature(s) canceled from the claim(s). No new matter should be entered.
Corrected drawing sheets in compliance with 37 CFR 1.121(d) are required in reply to the Office action to avoid abandonment of the application. Any amended replacement drawing sheet should include all of the figures appearing on the immediate prior version of the sheet, even if only one figure is being amended. The figure or figure number of an amended drawing should not be labeled as “amended.” If a drawing figure is to be canceled, the appropriate figure must be removed from the replacement sheet, and where necessary, the remaining figures must be renumbered and appropriate changes made to the brief description of the several views of the drawings for consistency. Additional replacement sheets may be necessary to show the renumbering of the remaining figures. Each drawing sheet submitted after the filing date of an application must be labeled in the top margin as either “Replacement Sheet” or “New Sheet” pursuant to 37 CFR 1.121(d). If the changes are not accepted by the examiner, the applicant will be notified and informed of any required corrective action in the next Office action. The objection to the drawings will not be held in abeyance.
Claim 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.
Claims 7, 8 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 pre-AIA the applicant regards as the invention.
Regarding Claim 7,
Claim 7, line 2 recites: “a first mark”. The corresponding structure for “a first mark” cannot be determined. It has been interpreted as any position. Claim 8 is rejected by virtue of its dependency on Claim 7.
Claim 7, line 3 recites: “a second mark”. The corresponding structure for “a second mark” cannot be determined. It has been interpreted as any position. Claim 8 is rejected by virtue of its dependency on Claim 7.
Claim 7, line 6 recites: “acquiring a first difference between intensities of diffracted light beams”. It is unclear how “acquiring a first difference between intensities of diffracted light beams” is different from “acquiring a difference between intensities of diffracted light beams” (recited in Claim 5, line 5, the claim from which this claim depends). It has been interpreted to mean any difference between intensities of diffracted light beams. Claim 8 is rejected by virtue of its dependency on Claim 7.
Claim 7, line 9 recites: “acquiring a second difference between intensities of diffracted light beams”. It is unclear how “acquiring a first difference between intensities of diffracted light beams” (Claim 7, line 6) is different from “acquiring a difference between intensities of diffracted light beams” (recited in Claim 5, line 5, the claim from which this claim depends) and “acquiring a second difference between intensities of diffracted light beams”. It has been interpreted to mean any difference between intensities of diffracted light beams. Claim 8 is rejected by virtue of its dependency on Claim 7.
Claim 7, line 12 recites: “the first intensity difference”. There is insufficient antecedent basis as no “a first intensity difference” has been claimed. It has been interpreted to mean any intensity. Claim 8 is rejected by virtue of its dependency on Claim 7.
Claim 7, line 12 recites: “a first reference intensity difference”. It is unclear how a first reference intensity difference is obtained. It has been interpreted to mean any intensity. Claim 8 is rejected by virtue of its dependency on Claim 7.
Claim 7, line 13 recites: “the second intensity difference”. There is insufficient antecedent basis as no “a second intensity difference” has been claimed. It has been interpreted to mean any intensity. Claim 8 is rejected by virtue of its dependency on Claim 7.
Claim 7, lines 13- recites: “a second reference intensity difference”. It is unclear how a second reference intensity difference is obtained. It has been interpreted to mean any intensity. Claim 8 is rejected by virtue of its dependency on Claim 7.
Regarding Claim 8,
Claim 8, line 3 recites: “acquiring a third difference between intensities of diffracted light beams”. It is unclear how “acquiring a third difference between intensities of diffracted light beams” is different from “acquiring a difference between intensities of diffracted light beams” (recited in Claim 5, line 5, the claim from which this claim depends), “acquiring a first difference between intensities of diffracted light beams, and “acquiring a second difference between intensities of diffracted light beams”. It has been interpreted to mean any difference between intensities of diffracted light beams.
Claim 8, line 6 recites: “acquiring a fourth difference between intensities of diffracted light beams”. It is unclear how “acquiring a fourth difference between intensities of diffracted light beams” is different from “acquiring a difference between intensities of diffracted light beams” (recited in Claim 5, line 5, the claim from which this claim depends), “acquiring a first difference between intensities of diffracted light beams, “acquiring a second difference between intensities of diffracted light beams”, and “acquiring a third difference between intensities of a diffracted light beams”. It has been interpreted to mean any difference between intensities of diffracted light beams.
Claim 8, line 9 recites: “the third intensity difference”. There is insufficient antecedent basis as no “a third intensity difference” has been claimed. It has been interpreted to mean any intensity.
Claim 8, line 9 recites: “a third reference intensity difference”. It is unclear how a third reference intensity difference is obtained. It has been interpreted to mean any intensity.
Claim 8, line 10 recites: “the fourth intensity difference”. There is insufficient antecedent basis as no “a fourth intensity difference” has been claimed. It has been interpreted to mean any intensity.
Claim 8, lines 9-10 recites: “a fourth reference intensity difference”. It is unclear how a third reference intensity difference is obtained. It has been interpreted to mean any intensity.
Claim Rejections - 35 USC § 102
The following is a quotation of the appropriate paragraphs of 35 U.S.C. 102 that form the basis for the rejections under this section made in this Office action:
A person shall be entitled to a patent unless –
(a)(1) the claimed invention was patented, described in a printed publication, or in public use, on sale or otherwise available to the public before the effective filing date of the claimed invention.
(a)(2) the claimed invention was described in a patent issued under section 151, or in an application for patent published or deemed published under section 122(b), in which the patent or application, as the case may be, names another inventor and was effectively filed before the effective filing date of the claimed invention.
Claim(s) 1-3, 5-7, 9-13, 15-17, 19-20 are rejected under 35 U.S.C. 102(a)(1) and 35 U.S.C. 102(a)(2) as being anticipated by Ho (US 9786569 B1).
Re: Independent Claim 1, Ho discloses:
A method for manufacturing a semiconductor device, the method comprising:
forming a stack (Ho, layers; Fig. 4A, elements 404, 406, collectively, can be considered a stack) on a wafer (Ho, substrate; Fig. 4G, element 402, Col. 4, lines 52 -53, "the substrate is a silicon substrate (e.g. a silicon wafer), wherein the stack includes a plurality of layers of the stack (Ho, Fig. 4A, shows the stack is made up of a plurality of layers, 404, 406);
forming a photoresist pattern (Ho, resist pattern; Fig. 4B, element 408, Col. 5, lines 42-43) on the stack (Ho, Fig. 4B shows 408 over a part of the stack, layer 406);
determining whether a material of at least one layer among the plurality of layers of the stack has changed (Ho, Col. 7, lines 28-36, material gets transferred to the existing layer 406, and therefore the material has changed, see also Col. 7, lines 53-57) and whether at least one process among a plurality of processes for forming the plurality of layers of the stack has changed (Ho, Col. 7, lines 49-55 discloses a change to the forming of layer 406);
changing a first wavelength for overlay measurement upon determination that the material of the at least one layer or the at least one process has changed (Ho, Col. 2, lines 47-63 discloses variable wavelengths used for the various layers);
and measuring an overlay using the changed first wavelength for overlay measurement (Ho, Col. 3).
Re: Dependent Claim 2, Ho disclose(s) all the limitations of claim 1 on which this claim depends. Ho further discloses:
wherein: the stack (Ho, layers; Fig. 4C, elements 404, 406, collectively, can be considered a stack) includes a first overlay mark (Ho, overlay mark; Fig. 4C, element 404a, can be considered a first overlay mark, see also Fig. 2),
the photoresist pattern (Ho, resist pattern; Fig. 4B, element 408, Col. 5, lines 42-43) includes a second overlay mark (Ho, overlay mark; Fig. 4C, element 408a, can be considered a second overlay mark, see also Fig. 2), and
determining whether the material of the at least one layer has changed includes:
acquiring a stack sensitivity based on a second wavelength (Ho, Col. 6, lines 38-47), the stack sensitivity (Ho, first overlay shift, Fig. 2, step 206) being based on a difference between intensities of diffracted light beams, and light irradiated to the first and second overlay marks being diffracted from the first and second overlay marks such that the diffracted light beams are generated (Ho, Fig. 2, Col. 6, lines 38-54);
comparing the stack sensitivity and a reference stack sensitivity with each other to obtain a Coefficient of Determination (Ho, real exposure-tool-induced overlay shift obtained by subtracting the first overlay shift from the estimate of the exposure-tool-induced overlay shift; Fig. 2, Cols. 6-7, lines 55 - 3);
and determining, when the Coefficient of Determination is greater than or equal to a critical value, that the material of the at least one layer has changed (Ho, Fig. 2, Steps 208 and 212, Cols. 6-7, lines 55 - 3).
Re: Dependent Claim 3, Ho disclose(s) all the limitations of claim 1 on which this claim depends. Ho further discloses:
wherein: forming the stack (Ho, layers; Fig. 4C, elements 404, 406, collectively, can be considered a stack), forming the photoresist pattern (Ho, resist pattern; Fig. 4B, element 408, Col. 5, lines 42-43), and determining whether the material of the at least one layer has changed and whether the at least one process has changed are performed on each of wafers of a lot (Ho, Fig. 2, Cols. 6-7, lines 63-3), and
changing the first wavelength for overlay measurement includes: grouping each of the wafers of the lot, based on the stack sensitivity of each of the wafers of the lot; and
changing the first wavelength for overlay measurement on a group basis (Ho, Fig. 2, Cols. 6-7, lines 63-3).
Re: Dependent Claim 5, Ho disclose(s) all the limitations of claim 1 on which this claim depends. Ho further discloses:
wherein: the stack (Ho, layers; Fig. 4C, elements 404, 406, collectively, can be considered a stack) includes a first overlay mark (Ho, overlay mark; Fig. 4C, element 404a, can be considered a first overlay mark, see also Fig. 2),
the photoresist pattern (Ho, resist pattern; Fig. 4B, element 408, Col. 5, lines 42-43) includes a second overlay mark (Ho, overlay mark; Fig. 4C, element 408a, can be considered a second overlay mark, see also Fig. 2), and
determining whether the at least one process has changed includes: acquiring a difference between intensities of diffracted light beams, and light irradiated to the first and second overlay marks being diffracted from the first and second overlay marks such that the diffracted light beams are generated (Ho, Col. 6, lines 38-54); and
determining whether the at least one process has changed, based on the difference between the intensities of the diffracted light beams (Ho, Fig. 2, steps 206, 208, 212).
Re: Dependent Claim 6, Ho disclose(s) all the limitations of claim 5 on which this claim depends. Ho further discloses:
wherein the light (Ho, radiation source; Fig. 1, element 104) includes a first light and a second light having different wavelengths (Ho, Col.2, lines 47-65).
Re: Dependent Claim 7, Ho disclose(s) all the limitations of claim 5 on which this claim depends. Ho further discloses:
wherein: each of the first and second overlay marks (Ho, overlay marks; Fig. 4C, elements 408a and 404a) includes a first mark (Ho, first overlay mark; Fig. 4C, element 404a) for measuring an overlay in a first direction and a second mark (Ho, second overlay mark; Fig. 4C, element 408a) for measuring an overlay in a second direction (Ho, Col. 9, lines 7-23),
and determining whether the at least one process has changed includes: acquiring a first difference between intensities of diffracted light beams, and first light irradiated to the first mark being diffracted from the first mark such that the diffracted light beams are generated;
acquiring a second difference between intensities of diffracted light beams, wherein the first light irradiated to the second mark is diffracted from the second mark such that the diffracted light beams are generated (Ho, Fig. 2, step 204 and 206, Cols. 5 and 6);
comparing the first intensity difference with a first reference intensity difference, and comparing the second intensity difference with a second reference intensity difference (Ho, Col. 8, lines 45-65); and
and determining whether the at least one process has changed, based on the comparing results (Ho, Fig. 2 and 3).
Re: Dependent Claim 9, Ho disclose(s) all the limitations of claim 1 on which this claim depends. Ho further discloses:
wherein: the stack (Ho, layers; Fig. 4C, elements 404, 406, collectively, can be considered a stack) includes a first overlay mark (Ho, overlay mark; Fig. 4C, element 404a, can be considered a first overlay mark, see also Fig. 2),
the photoresist pattern (Ho, resist pattern; Fig. 4B, element 408, Col. 5, lines 42-43) includes a second overlay mark (Ho, overlay mark; Fig. 4C, element 408a, can be considered a second overlay mark, see also Fig. 2),
determining whether the at least one process has changed includes: acquiring an image contrast of each of the first overlay mark and the second overlay mark (Ho, Col. 6, lines 38-54), based on a third wavelength (Ho, Col. 2, lines 32-46);
comparing the image contrast with a reference image contrast and acquiring a Coefficient of Determination based on the comparing result; and
determining, when the Coefficient of Determination is greater than or equal to a critical value, that the at least one process has changed (Ho, Figs. 2-3, Col. 3, lines 37 -55).
Re: Dependent Claim 10, Ho disclose(s) all the limitations of claim 1 on which this claim depends. Ho further discloses:
wherein: the stack (Ho, layers; Fig. 4C, elements 404, 406, collectively, can be considered a stack) includes a first overlay mark (Ho, overlay mark; Fig. 4C, element 404a, can be considered a first overlay mark, see also Fig. 2),
the photoresist pattern (Ho, resist pattern; Fig. 4B, element 408, Col. 5, lines 42-43) includes a second overlay mark (Ho, overlay mark; Fig. 4C, element 408a, can be considered a second overlay mark, see also Fig. 2), and
determining whether the material of the at least one layer has changed includes: measuring an overlay based on a second wavelength (Ho, Figs. 2 and 3);
creating a graph of the overlay based on the second wavelength (Ho, Cols 10 -11, lines 64-31);
comparing the graph and a reference graph with each other (Ho, Cols 10 -11, lines 64-31);
and determining whether the material of the at least one layer has changed, based on the comparing result (Ho, Cols 10 -11, lines 64-31).
Re: Independent Claim 11, Ho discloses:
A method for manufacturing a semiconductor device, the method comprising:
forming a stack (Ho, layers; Fig. 4A, elements 404, 406, collectively, can be considered a stack) on a wafer (Ho, substrate; Fig. 4G, element 402, Col. 4, lines 52 -53, "the substrate is a silicon substrate (e.g. a silicon wafer), wherein the stack includes a plurality of layers of the stack (Ho, Fig. 4A, shows the stack is made up of a plurality of layers, 404, 406);
forming a photoresist pattern (Ho, resist pattern; Fig. 4B, element 408, Col. 5, lines 42-43) on the stack (Ho, Fig. 4B shows 408 over a part of the stack, layer 406);
determining whether a material of at least one layer among the plurality of layers of the stack has changed (Ho, Col. 7, lines 28-36, material gets transferred to the existing layer 406, and therefore the material has changed) and whether at least one process among a plurality of processes for forming the plurality of layers of the stack has changed (Ho, Col. 7, lines 49-55 discloses a change to the forming of layer 406);
changing a first wavelength for overlay measurement upon determination that the material of the at least one layer or the at least one process has changed (Ho, Col. 2, lines 47-63 discloses variable wavelengths used for the various layers);
aligning the wafer using the changed first wavelength for alignment (Ho, Col. 3, lines 19-36);
and developing the photoresist pattern to generate a developed photoresist pattern (Ho, Col. 3, lines 19-36).
Re: Dependent Claim 12, Ho disclose(s) all the limitations of claim 11 on which this claim depends. Ho further discloses:
wherein: the stack (Ho, layers; Fig. 4C, elements 404, 406, collectively, can be considered a stack) includes an alignment mark (Ho, overlay mark; Fig. 4C, element 404a, can be considered an alignment mark, Col. 3, lines 19-20, see also Fig. 2), and
determining whether the material of the at least one layer has changed includes:
acquiring a wafer quality, based on a second wavelength, the wafer quality being based on a difference between intensities of diffracted light beams (Ho, Col. 6, lines 38-47) light irradiated to the alignment mark being diffracted from the alignment mark such that the diffracted light beams are generated;
comparing the wafer quality and a reference wafer quality with each other;
and determining whether the material of the at least one layer has changed, based on the comparing result (Ho, Fig. 2, Steps 208 and 212, Cols. 6-7, lines 55 - 3).
Re: Dependent Claim 13, Ho disclose(s) all the limitations of claim 12 on which this claim depends. Ho further discloses:
wherein: forming the stack (Ho, layers; Fig. 4C, elements 404, 406, collectively, can be considered a stack), forming the photoresist pattern (Ho, resist pattern; Fig. 4B, element 408, Col. 5, lines 42-43), and determining whether the material of the at least one layer has changed and whether the at least one process has changed are performed on each of wafers of a lot (Ho, Fig. 2, Cols. 6-7, lines 63-3), and
changing the first wavelength for alignment includes:
grouping each of the wafers of the lot, based on the wafer quality of each of the wafers of the lot (Ho, Fig. 2, Cols. 6-7, lines 63-3); and
changing the first wavelength for alignment on a group basis (Ho, Fig. 2, Cols. 6-7, lines 63-3).
Re: Dependent Claim 15, Ho disclose(s) all the limitations of claim 11 on which this claim depends. Ho further discloses:
wherein: the stack (Ho, layers; Fig. 4C, elements 404, 406, collectively, can be considered a stack) includes an alignment mark (Ho, overlay mark; Fig. 4C, element 404a, can be considered an alignment mark, Col. 3, lines 19-20, see also Fig. 2), and
determining whether the material of the at least one layer has changed includes: identifying a position of the alignment mark based on a second wavelength (Ho, Col. 7, lines 28-55);
generating a graph of the position of the alignment mark based on the second wavelength (Ho, Cols 10 -11, lines 64-31);
comparing the graph and a reference graph with each other (Ho, Cols 10 -11, lines 64-31); and
determining whether the material of the at least one layer has changed, based on the comparing result (Ho, Cols 10 -11, lines 64-31).
Re: Independent Claim 16, Ho disclose(s):
A method for manufacturing a semiconductor device, the method comprising:
forming a stack (Ho, layers; Fig. 4A, elements 404, 406, collectively, can be considered a stack) on a wafer (Ho, substrate; Fig. 4G, element 402, Col. 4, lines 52 -53, "the substrate is a silicon substrate (e.g. a silicon wafer), wherein the stack includes a plurality of layers of the stack (Ho, Fig. 4A, shows the stack is made up of a plurality of layers, 404, 406);
forming a photoresist pattern (Ho, resist pattern; Fig. 4B, element 408, Col. 5, lines 42-43) on the stack (Ho, Fig. 4B shows 408 over a part of the stack, layer 406);
aligning the wafer, and then developing the photoresist pattern to aligning the wafer, and then developing the photoresist pattern to generate a developed photoresist pattern (Ho, Figs. 2-3, Col. 3, lines 19-36);
determining whether a material of at least one layer of the plurality of layers of the stack has changed (Ho, Col. 7, lines 28-36, material gets transferred to the existing layer 406, and therefore the material has changed) and whether at least one process among a plurality of process for forming the plurality of layers of the stack has changed (Ho, Col. 7, lines 49-55 discloses a change to the forming of layer 406);
changing a measurement wavelength upon determination that the material of the at least one layer or the at least one process has changed (Ho, Figs. 2 and 3);
and aligning the wafer and/or measuring an overlay of the developed photoresist pattern using the changed measurement wavelength (Ho, Figs. 2-3, Cols 2-3).
Re: Dependent Claim 17, Ho disclose(s) all the limitations of claim 16 on which this claim depends. Ho further discloses:
wherein: forming the stack (Ho, layers; Fig. 4C, elements 404, 406, collectively, can be considered a stack, forming the photoresist pattern (Ho, resist pattern; Fig. 4B, element 408, Col. 5, lines 42-43,and determining whether the material of the at least one layer has changed, and whether the at least one process has changed are performed on each of wafers of a lot (Ho, Cols. 6-7, lines 66-3), and
changing the measurement wavelength includes:
grouping each of the wafers of the lot; and
and changing the measurement wavelength on a group basis (Ho, Col. 6, lines 16-27).
Re: Dependent Claim 19, Ho disclose(s) all the limitations of claim 16 on which this claim depends. Ho further discloses:
further comprising determining whether the overlay is greater than or equal to a critical value (Ho, threshold; Fig. 2, steps 206, 208, Col. 6, lines 38-54, see also Col. 7, lines 4-15).
Re: Dependent Claim 20, Ho disclose(s) all the limitations of claim 19 on which this claim depends. Ho further discloses:
further comprising: removing the developed photoresist pattern (Ho, resist layer; Fig. 4B, element 408) upon determination that the overlay is equal to or greater than the critical value;
and etching the stack using the developed photoresist pattern upon determination that the overlay is smaller than the critical value (Ho, Figs. 2-3, Col. 7, lines 4-62).
Claim Rejections - 35 USC § 103
The following is a quotation of AIA 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 of this title, 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 4, 14, 18 are rejected under AIA 35 U.S.C. 103 as being unpatentable over Ho (US 9786569 B1) in view of Hsieh (US 10969697 B1).
Re: Dependent Claim 4, Ho discloses all the limitations of claim 2 on which this claim depends. Ho further discloses:
wherein: forming the stack (Ho, layers; Fig. 4C, elements 404, 406, collectively, can be considered a stack, forming the photoresist pattern (Ho, resist pattern; Fig. 4B, element 408, Col. 5, lines 42-43,and determining whether the material of the at least one layer has changed, and whether the at least one process has changed are performed on each of the wafers (Ho, Cols. 6-7, lines 66-3),
Ho does not explicitly disclose:
provided for a predefined period of time, and
changing the first wavelength for overlay measurement includes: grouping each of the wafers provided for the predefined period of time, based on the stack sensitivity of each of the wafers; and changing the first wavelength for overlay measurement based on a group basis.
Hsieh discloses:
provided for a predefined period of time, and changing the first wavelength for overlay measurement includes: grouping each of the wafers provided for the predefined period of time, based on the stack sensitivity of each of the wafers; and changing the first wavelength for overlay measurement based on a group basis (Hsieh, Col. 3, lines 3 - 26).
Ho discloses an overlay measurement system, process on wafers, and determining whether the material of the at least one process has changed. Ho does not explicitly disclose performing on each of the wafers for a predefined period of time. Hsieh discloses an overlay tool and the metrology method largely dependent on measurement time. Ho and Hsieh both disclose overlay measurements and tools, and are therefore analogous art. It would be obvious to a person of ordinary skill in the art (POSITA) before the effective filing date to include measurements on the wafers of the lot for a predetermined time, as disclosed by Hsieh, arriving at the invention as claimed, for the benefit of robust overlay measurements (Hsieh, Col. 3, lines 3-26).
Re: Dependent Claim 14, Ho discloses all the limitations of claim 12 on which this claim depends. Ho further discloses:
wherein: forming the stack (Ho, layers; Fig. 4C, elements 404, 406, collectively, can be considered a stack, forming the photoresist pattern (Ho, resist pattern; Fig. 4B, element 408, Col. 5, lines 42-43,and determining whether the material of the at least one layer has changed, and whether the at least one process has changed are performed on each of the wafers (Ho, Cols. 6-7, lines 66-3),
Ho does not explicitly disclose:
provided for a predefined period of time, and
changing the first wavelength for alignment includes: grouping each of the wafers provided for the predefined period of time, based on the wafer quality of each of the wafers; and changing the first wavelength for alignment based on a group basis.
Hsieh discloses:
provided for a predefined period of time, and changing the first wavelength for alignment includes: grouping each of the wafers provided for the predefined period of time, based on the wafer quality of each of the wafers; and changing the first wavelength for alignment based on a group basis (Hsieh, Col. 3, lines 3 - 26).
Ho discloses an overlay measurement system, process on wafers, and determining whether the material of the at least one process has changed. Ho does not explicitly disclose performing on each of the wafers for a predefined period of time. Hsieh discloses an overlay tool and the metrology method largely dependent on measurement time. Ho and Hsieh both disclose overlay measurements and tools, and are therefore analogous art. It would be obvious to a person of ordinary skill in the art (POSITA) before the effective filing date to include measurements on the wafers of the lot for a predetermined time, as disclosed by Hsieh and arriving at the invention as claimed, for the benefit of robust overlay measurements (Hsieh, Col. 3, lines 3-26).
Re: Dependent Claim 18, Ho discloses all the limitations of claim 16 on which this claim depends. Ho further discloses:
wherein: forming the stack (Ho, layers; Fig. 4C, elements 404, 406, collectively, can be considered a stack, forming the photoresist pattern (Ho, resist pattern; Fig. 4B, element 408, Col. 5, lines 42-43,and determining whether the material of the at least one layer has changed, and whether the at least one process has changed are performed on each of wafers (Ho, Cols. 6-7, lines 66-3) of a lot,
Ho does not explicitly disclose:
provided for a predefined period of time, and
changing the first wavelength for overlay measurement includes: grouping each of the wafers provided for the predefined period of time, based on the stack sensitivity of each of the wafers; and changing the first wavelength for overlay measurement based on a group basis.
Hsieh discloses:
provided for a predefined period of time, and
changing the first wavelength for overlay measurement includes: grouping each of the wafers provided for the predefined period of time, based on the stack sensitivity of each of the wafers; and changing the first wavelength for overlay measurement based on a group basis (Hsieh, Col. 3, lines 3 - 26).
Ho discloses an overlay measurement system, process on wafers, and determining whether the material of the at least one process has changed. Ho does not explicitly disclose performing on each of the wafers for a predefined period of time. Hsieh discloses an overlay tool and the metrology method largely dependent on measurement time. Ho and Hsieh both disclose overlay measurements and tools, and are therefore analogous art. It would be obvious to a person of ordinary skill in the art (POSITA) before the effective filing date to include measurements on the wafers of the lot for a predetermined time, as disclosed by Hsieh, arriving at the invention as claimed, for the benefit of robust overlay measurements (Hsieh, Col. 3, lines 3-26).
Claims 8 is rejected under AIA 35 U.S.C. 103 as being unpatentable over Ho (US 9786569 B1).
Re: Dependent Claim 8, Ho discloses all the limitations of claim 7 on which this claim depends. Ho further discloses:
wherein: determining whether the at least one process has changed further includes: acquiring a third difference between intensities of diffracted light beams, second light irradiated to the first mark being diffracted from the first mark such that the diffracted light beams are generated;
comparing the third intensity difference with a third reference intensity difference, and determining whether the at least one process has changed, based on the comparing results, the second light being polarized light of the first light (Ho, Figs. 2-3 demonstrates checking overlay shift which determines whether the process has changed)
Ho does not explicitly disclose:
acquiring a fourth difference between intensities of diffracted light beams, the second light irradiated to the second mark being diffracted from the second mark such that the diffracted light beams are generated; and comparing the fourth intensity difference with a fourth reference intensity difference;
Ho discloses acquiring intensity differences but does not explicitly disclose a fourth intensity difference. It would be obvious to a POSITA before the effective filing date to perform a re-work for a fourth time (in Ho, Fig. 3), acquiring a fourth intensity difference, meeting the invention as claimed, for the benefit of better layer alignment.
Prior art made of record and not relied upon are considered pertinent to current application disclosure.
Demirer (US 11221561 B2), Van Mierlo (US 20250044709 A1), Cekli (US 9753377 B2), Abdulhalim (US 20150300815 A1), and Den Boef (US 8339595 B2) disclose overlay measurement tools, lithographic apparatuses, pattern forming and transferring, techniques to control misalignment between two layers.
Conclusion
Any inquiry concerning this communication or earlier communications from the examiner should be directed to NIMARTA KAUR CHOWDHARY whose telephone number is (571)272-7679. The examiner can normally be reached usually Monday - Thursday, 6:45 AM - 4:45 PM (EST).
Examiner interviews are available via telephone, in-person, and video conferencing using a USPTO supplied web-based collaboration tool. To schedule an interview, applicant is encouraged to use the USPTO Automated Interview Request (AIR) at http://www.uspto.gov/interviewpractice.
If attempts to reach the examiner by telephone are unsuccessful, the examiner’s supervisor, Leonard Chang can be reached at (571) 270-3691. The fax phone number for the organization where this application or proceeding is assigned is 571-273-8300.
Information regarding the status of published or unpublished applications may be obtained from Patent Center. Unpublished application information in Patent Center is available to registered users. To file and manage patent submissions in Patent Center, visit: https://patentcenter.uspto.gov. Visit https://www.uspto.gov/patents/apply/patent-center for more information about Patent Center and https://www.uspto.gov/patents/docx for information about filing in DOCX format. For additional questions, contact the Electronic Business Center (EBC) at 866-217-9197 (toll-free). If you would like assistance from a USPTO Customer Service Representative, call 800-786-9199 (IN USA OR CANADA) or 571-272-1000.
/NIMARTA KAUR CHOWDHARY/ Examiner, Art Unit 2898
/Leonard Chang/ Supervisory Patent Examiner, Art Unit 2898
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