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 .
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and the fee set forth in 37 CFR 1.17(e) has been timely paid, the finality of the previous Office action has been withdrawn pursuant to 37 CFR 1.114.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 March 30, 2026 has been entered.
Status of the Claims
Species 1, as shown in FIGs. 4A-R was elected.
Amendment fled March 30, 2026 is acknowledged. Claims 1, 18 and 29 have been amended. Claims 1-5, 8, 18-19, 21-22, 24-25, 28-31 and 35-38 are pending.
Action on merits of claims 1-5, 8, 18-19, 21-22, 24-25, 28-31 and 35-38 follows.
Claim Rejections - 35 USC § 112
The following is a quotation of the first paragraph of 35 U.S.C. 112(a):
(a) IN GENERAL.—The specification shall contain a written description of the invention, and of the manner and process of making and using it, in such full, clear, concise, and exact terms as to enable any person skilled in the art to which it pertains, or with which it is most nearly connected, to make and use the same, and shall set forth the best mode contemplated by the inventor or joint inventor of carrying out the invention.
Claims 1-5, 8, 18-19, 21-22, 24-25, 28-31 and 35-38 are rejected under 35 U.S.C. 112(a) or 35 U.S.C. 112 (pre-AIA ), first paragraph, as failing to comply with the written description requirement. The claim(s) contains subject matter which was not described in the specification in such a way as to reasonably convey to one skilled in the relevant art that the inventor or a joint inventor, or for applications subject to pre-AIA 35 U.S.C. 112, the inventor(s), at the time the application was filed, had possession of the claimed invention.
There does not appear to be a written description of the claim limitation “depositing (forming), in the first set of trenches, a blocking material that protects the first set of trenches from being etched during formation of a second set of trenches” (amended independent claims 1, 18 and 29) (emphasis added) in the application as filed.
However, the instant application, ¶ [0067] discloses:
[0067] As further shown in FIG. 4K, the second etch operation may result in portions of the first plurality of trenches 408 being exposed in locations where the first plurality of trenches 408 and the second plurality of trenches 418 intersect. However, the blocking material 410 blocks or prevents the exposed portions of the first plurality of trenches 408 from being further etched during the second etch operation, which reduces and/or prevents etch loading and/or over etching at and/or near the intersections of the first plurality of trenches 408 and the second plurality of trenches 418. (Emphasis added).
That means the blocking layer 410 at the intersection of the first 408 and second 418 set of trenches are removed, when the second set of trenches are being etched.
Therefore, the limitation “a blocking material that protects the first set of trenches from being etched during formation of a second set of trenches” is new matter.
Applicant must cancel the un-support new matters in response to the Office Action.
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 1-5, 8, 18-19, 21-22, 24-25, 28-31 and 35-38 are rejected under 35 U.S.C. 112(b) or 35 U.S.C. 112 (pre-AIA ), second paragraph, as being indefinite for failing to particularly point out and distinctly claim the subject matter which the inventor or a joint inventor (or for applications subject to pre-AIA 35 U.S.C. 112, the applicant), regards as the invention.
Amended claims 1, 18 and 29 recites: “depositing (forming), in the first set of trenches, a blocking material that protects the first set of trenches from being etched during formation of a second set of trenches”.
However, according to the disclosure, ¶ [0067], as discussed above, during the etching of the second set of trenches 418, the blocking material 410 at the intersection of the first 408 and second 418, set of trenches are removed to expose the first trenches 408.
Claims 1, 18 and 29 contravene the disclosure, therefore, claims 1, 18 and 29 and all dependent claims are indefinite.
Claim 37 recites the limitation “the method of claim 1, wherein the blocking material is removed from the first set of trenches in a same operation as removal of the second ARC layer and the second photoresist layer”. There is insufficient antecedent basis for this limitation in the claim.
In claim 1, “the second ARC and the second photoresist layer” have never been removed.
Therefore, the limitation of claim 37 lacks antecedent support.
Claim Rejections - 35 USC § 103
The text of those sections of Title 35, U.S. Code not included in this action can be found in a prior Office action.
Claims 1-5, 8, 29-31 and 35-38 are rejected under 35 U.S.C. 103 as being unpatentable over CHO et al. (US. Pub. No. 2021/0202547) of record, in view of DOFUKU (US. Pub. No. 2021/0082984).
With respect to claim 1, As best understood by the Examiner, CHO teaches a method substantially as claimed, including:
forming a first photoresist layer (not shown) over a first antireflective coating (ARC) layer (not shown) that is over a substrate (100);
forming a first pattern in the first photoresist layer based on removing one or more portions of the first photoresist layer up to the first ARC layer (not shown);
etching, based on the first pattern, the first ARC layer and the substrate (100) to form a first set of trenches (130Ta) in a first direction (D1) within the substrate;
removing the first photoresist layer after etching the substrate to form the first set of trenches (130Ta);
depositing, in the first set of trenches, a blocking material (ML) that protects the first set of trenches from being etched during formation of a second set of trenches (130Tb);
forming, after removing the first photoresist layer, a second photoresist layer (not shown) over a second ARC layer (not shown) that is over the substrate (100),
wherein the second photoresist layer (not shown) and the second ARC layer (not shown) are formed over the blocking material (ML) in the first set of trenches (130Ta);
forming a second pattern (not shown) in the second photoresist layer based on removing one or more portions of the second photoresist layer up to the second ARC layer;
etching, based on the second pattern, and while the blocking material (ML) remains in the first set of trenches, the second ARC layer and the substrate to form the second set of trenches (130Tb) in a second direction (D2) within the substrate;
removing the blocking material (ML) from the first set of trenches (130Ta) after forming the second set of trenches (130Tb); and
forming, after removing the blocking material (ML), a deep trench isolation (DTI) structure (130) of a pixel array in the first set of trenches (130Ta) and the second set of trenches (130Tb). (See FIGs. 31-35C).
Thus, CHO is shown to teach all the features of the claim with the exception of explicitly showing the formation of the first mask pattern and the second mask pattern.
Note that, the formation of the pattern mask is well-known in the art.
However, DOFUKU teaches a method including:
forming a mask pattern, wherein forming the mask pattern including forming a photoresist layer (152) over a first antireflective coating (ARC) layer (151) that is over a substrate (121); (FIGs. 6A-B)
forming a first pattern in the first photoresist layer (152) based on removing one or more portions of the first photoresist layer (152) up to the first ARC layer (151); and
etching, based on the first pattern, the first ARC layer (151) and the substrate (121) to form a first set of trenches (121A) in a first direction within the substrate;
removing the first photoresist layer (152) after etching the substrate (121) to form the first set of trenches (121A); (FIG. 6C).
Note that, the formation of the second pattern and etching to form the second set of trenches is the same as or repeating the same process of forming the first pattern and etching to form first set of trenches.
Therefore, it would have been obvious to one having ordinary skill in the art at the time of invention was made to form the first pattern and the second pattern of CHO having the photoresist layer over the ARC layer as taught by DOFUKU to provide the etch mask for the formation of the first set of trenches and the second set of trenches.
With respect to claim 2, the method of CHO further comprises: filling the first set of trenches (130Ta) and the second set of trenches (130Tb) with an oxide material to form the DTI structure (130).
With respect to claim 3, the method of CHO further comprises: forming photodiodes (PD) for pixel sensors, wherein the first set of trenches (130Ta) and the second set of trenches (130Tb) are formed in between the photodiodes (PD).
With respect to claim 4, In view of DOFUKU, the method further includes:
forming the first ARC (151) over the substrate prior to forming the first photoresist layer (152) over the first ARC (151); and
removing the first ARC (151) after forming of the first set of trenches and, thus before forming the second photoresist layer (second mask pattern).
With respect to claim 5, the first direction (D1) and the second direction (D2) of CHO are approximately perpendicular such that the first set of trenches (130Ta) and the second set of trenches (130Tb) intersect at a plurality of locations in the substrate.
With respect to claim 8, in view of DOFUKU, a ratio between a depth of the first set of trenches and a width of the first set of trenches is in a range of approximately 5 to 25, thus overlaps claimed range of approximately 20 to approximately 50; and wherein a ratio between a depth of the second set of trenches and a width of the second set of trenches is in the range of approximately 5 to 25, thus overlaps claimed range of 20 to approximately 50.
It is well settled that "[W]here the general conditions of a claim are disclosed in the prior art, it is not inventive to discover the optimum or workable ranges by routine experimentation." In re Aller, 220 F.2d 454, 456, 105 USPQ 233, 235 (CCPA 1955) (Claimed process which was performed at a temperature between 40 ºC and 80 ºC and an acid concentration between 25% and 70% was held to be prima facie obvious over a reference process which differed from the claims only in that the reference process was performed at a temperature of 100 ºC and an acid concentration of 10%.); see also Peterson, 315 F.3d at 1330, 65 USPQ2d at 1382 ("The normal desire of scientists or artisans to improve upon what is already generally known provides the motivation to determine where in a disclosed set of percentage ranges is the optimum combination of percentages.").
With respect to claim 35, the DTI structure (130) of CHO extends to a depth greater than a depth of the photodiodes.
With respect to claim 36, an aspect ratio of the DTI structure (130) of CHO increases a full well capacity of pixel sensors (PXR) isolated by the DTI structure.
With respect to claim 37, As best understood by the Examiner, the blocking material (ML) of CHO is removed from the first set of trenches in a same operation as removal of the second ARC layer and the second photoresist layer.
Since the blocking material (ML) “may be removed after the formation of the first and second trenches 130Ta and 130Tb” and before the formation of the DTI 130, therefore, it would have been obvious to one having ordinary skill in the art at the time of invention was made to remove the blocking material (ML) and the second pattern in the same operation to simplify the process.
Moreover, the blocking material and the second pattern can be removed in a same or separate operations, hence obvious design choice.
With respect to claim 38, in view of DOFUKU, the DTI structure (130) of CHO has a height in a range of approximately 2 microns to approximately 4 microns and a width in a range of approximately 80 nanometers to approximately 100 nanometers.
It is well settled that "[W]here the general conditions of a claim are disclosed in the prior art, it is not inventive to discover the optimum or workable ranges by routine experimentation." In re Aller, 220 F.2d 454, 456, 105 USPQ 233, 235 (CCPA 1955) (Claimed process which was performed at a temperature between 40 ºC and 80 ºC and an acid concentration between 25% and 70% was held to be prima facie obvious over a reference process which differed from the claims only in that the reference process was performed at a temperature of 100 ºC and an acid concentration of 10%.); see also Peterson, 315 F.3d at 1330, 65 USPQ2d at 1382 ("The normal desire of scientists or artisans to improve upon what is already generally known provides the motivation to determine where in a disclosed set of percentage ranges is the optimum combination of percentages.").
With respect to claim 29, As best understood by the Examiner, CHO teaches a method substantially as claimed, including:
forming photodiodes (PXR) for pixel sensors of a pixel array in a substrate (100);
forming a first photoresist pattern (not shown) in a first layer over the substrate based on removing one or more portions of the first layer (not shown) up to a first antireflective coating (ARC) layer (not shown) that is between the first layer and the substrate;
etching, based on the first photoresist pattern, the substrate (100) to form a first set of trenches (130Ta) between the photodiodes (PXR) in a first direction (D1) within the substrate;
forming, in the first set of trenches (130Ta), a blocking material (ML) that protects the first set of trenches (130Ta) from being etched during formation of a second set of trenches (130Tb);
forming a second photoresist pattern (not shown) in a second layer over the substrate based on removing one or more portions of the second layer up to a second ARC layer (not shown) that is between the second layer and the substrate;
wherein the second layer (not shown) and the second ARC layer (not shown) are formed over the blocking material (ML) in the first set of trenches (130Ta);
etching, based on the second photoresist pattern (not shown) and while the blocking material (ML) layer remains in the first set of trenches (130Ta), the substrate to form the second set of trenches (130Tb) between the photodiodes (PXR) in a second direction (D2) within the substrate;
removing the blocking material (ML) after forming the second set of trenches (130Tb); and
forming, after removing the blocking material (ML), a deep trench isolation (DTI) structure (130) of the pixel array in the first set of trenches (130Ta) and the second set of trenches (130Tb). (FIGs. 31-35C).
Thus, CHO is shown to teach all the features of the claim with the exception of explicitly showing the formation of the first photoresist pattern and the second photoresist pattern.
Note that, the formation of the photoresist pattern is well-known in the art.
However, DOFUKU teaches a method including:
forming a mask pattern, wherein forming the mask pattern including forming a photoresist layer (152) over a first antireflective coating (ARC) layer (151) that is over a substrate (121); (FIGs. 6A-B)
forming a first pattern in the first photoresist layer (152) based on removing one or more portions of the first photoresist layer (152) up to the first ARC layer (151); and
etching, based on the first photoresist pattern (152), the substrate (121) to form a first set of trenches (121A) in a first direction within the substrate. (FIG. 6C).
Note that, “forming a second photoresist pattern and etching to form a second set of trenches in a second direction within the substrate” of CHO is the same as or repeating the formation of the first photoresist pattern and etching to form the first set of trenches.
Therefore, it would have been obvious to one having ordinary skill in the art at the time of invention was made to form the first photoresist pattern and the second photoresist pattern of CHO having the first and second photoresist layer over the first and second ARC layer, respectively, as taught by DOFUKU to provide the etch mask for the formation of the first set of trenches and the second set of trenches.
With respect to claim 30, in view of DOFUKU, the first layer (152) is a first photoresist layer, further includes: removing the first photoresist layer (152), wherein the second layer (152) is a second photoresist layer that is formed after removing the first photoresist layer.
With respect to claim 31, the blocking material (ML) of CHO includes one or more of an ARC material, or a photoresist material.
Claims 18-19, 21-22, 24-25 and 28 are rejected under 35 U.S.C. 103 as being unpatentable over CHO ‘547 in view of DOFUKU ‘984 and JANGJIAN et al. (US. Patent No. 9,219,092) of record.
With respect to claim 18, As best understood by the Examiner, CHO teaches a method substantially as claimed including:
forming a plurality of trenches in a substrate of a pixel array based on:
forming a first pattern (not shown) in a first material layer over the substrate based on removing one or more portions of the first material layer (not shown) up to a first antireflective coating (ARC) layer that is between the first material (not shown) and the substrate (100);
forming a first subset (130Ta) of trenches, of the plurality of trenches, in the substrate (100) based on the first pattern (not shown);
forming, in the first subset (130Ta) of trenches, a blocking material (ML) that protects the first subset (130Ta) of the trenches from being etched during formation of a second subset (130Tb) of trenches;
forming a second pattern (not shown) in a third material layer over the substrate based on removing one or more portions of the third material layer (not shown) up to a second ARC layer that is between the third material (not shown) and the substrate (100);
wherein the third material and the second ARC layer (not shown) are formed over the blocking material (ML) in the first subset (130Ta) of trenches;
removing the blocking material (ML) after forming the second subset (130Tb) of trenches;
filling, after removing the blocking material (ML), the plurality of trenches to form a deep trench isolation (DTI) structure (130) in the substrate (100);
forming a metal layer (210) over the substrate and over the DTI structure (130);
etching through the metal layer (210) to form a grid structure (210);
forming color filter regions (200) for the pixel sensors in between the grid structure (210); and
forming a micro-lens layer (220) of the pixel array over the grid structure (210) and over the color filter regions (200). (See FIGs. 4A, 31-35C).
Thus, CHO is shown to teach all the features of the claim with the exception of explicitly showing the formation of the first patterns and second patterns; and the grid structure including a dielectric layer and a metal layer.
However, DOFUKU teaches a method including:
forming a plurality of trenches in a substrate of an array based on:
forming a first pattern in a first material layer (152) over substrate (121) based on removing one or more portions of the first material layer (152) up to a first anti-reflective coating (151) that is between the first material layer (152) and the substrate (121);
forming a first subset of trenches (121A), of the plurality of trenches, in the substrate based on the first pattern;
forming a second pattern is a third material layer (152) over the substrate based on removing one or more portions of the third material layer (152) up to a second ARC layer (151) that is between the third material layer (152) and the substrate. (See FIGs. 6A-C).
Note that, “forming the second pattern and forming the second set of trenches, based on the second pattern” of CHO is the same as or repeating the same formation of the first pattern and forming the first set of trenches.
Therefore, it would have been obvious to one having ordinary skill in the art at the time of invention was made to form the first pattern and the second pattern CHO having the first pattern and the second pattern in the first material and the third material, respectively, over the first and second ARC layer that is between the first and third layer and the substrate, respectively, as taught by DOFUKU to provide the etch mask for the formation of the first subset and the second subset of trenches.
Further, JANGJIAN teaches a method including:
forming a dielectric layer (38) over substrate (26) and over photodiodes (24);
forming a metal layer (42) over the dielectric layer (38);
etching through the metal layer (42) and into a portion of the dielectric layer (38) to form a grid structure (46). (See FIGs. 1-2).
Therefore, it would have been obvious to one having ordinary skill in the art before the filling date of the claimed invention to form the grid structure of CHO including forming the dielectric layer over the substrate and etching through the metal layer and into a portion of the dielectric layer as taught by JANGJIAN to protect the ARC from etching.
With respect to claim 19, forming the plurality of trenches of CHO comprises:
forming the first subset (130Ta) of the plurality of trenches by etching the first subset (130Ta) of the plurality of trenches using the first pattern; and
forming the second subset (130Tb) of the plurality of trenches by etching the second subset (130Tb) of the plurality of trenches using a second photoresist pattern.
With respect to claim 21, in view of DOFUKU, the first pattern is a first photoresist pattern and the first material (152) is a first photoresist layer.
With respect to claim 22, in view of DOFUKU, the method of CHO further includes:
removing the first pattern, hence, removing the first material layer (152) after forming the first subset (130Ta) of trenches; and
forming the second pattern, hence forming that third material layer (152), after removing the first pattern, hence removing the material layer (152), wherein the third material layer (152) is a second photoresist layer and the second pattern is a second photoresist pattern.
With respect to claim 24, the first subset (130Ta) of trenches of CHO is formed in a first direction (D1) and the second subset (130Tb) of trenches is formed in a second direction (D2).
With respect to claim 25, the first subset (130Ta) of trenches and the second subset (130Tb) of trenches of CHO intersect at a plurality of locations in the substrate.
With respect to claim 28, in view of DOFUKU, a ratio between a depth of the first set of trenches and a width of the first set of trenches is in a range of approximately 5 to 25, thus overlaps claimed range of approximately 20 to approximately 50; and wherein a ratio between a depth of the second set of trenches and a width of the second set of trenches is in the range of approximately 5 to 25, thus overlaps claimed range of 20 to approximately 50.
It is well settled that "[W]here the general conditions of a claim are disclosed in the prior art, it is not inventive to discover the optimum or workable ranges by routine experimentation." In re Aller, 220 F.2d 454, 456, 105 USPQ 233, 235 (CCPA 1955) (Claimed process which was performed at a temperature between 40 ºC and 80 ºC and an acid concentration between 25% and 70% was held to be prima facie obvious over a reference process which differed from the claims only in that the reference process was performed at a temperature of 100 ºC and an acid concentration of 10%.); see also Peterson, 315 F.3d at 1330, 65 USPQ2d at 1382 ("The normal desire of scientists or artisans to improve upon what is already generally known provides the motivation to determine where in a disclosed set of percentage ranges is the optimum combination of percentages.").
Response to Arguments
Applicant's arguments filed June 30, 2026 have been fully considered but they are not persuasive.
Applicant argues:
Accordingly, CHO teaches that the mask layer ML is etched during formation of the second trenches 130Tb. Specifically, CHO states that formation of the second trenches includes "etching the substrate 100 and the mask layer ML using the second mask pattern as an etch mask." Thus, CHO's mask layer ML is not configured to protect the first trenches from being etched during formation of the second trenches, as recited in amended claim 1. Rather, CHO teaches that the mask layer ML itself is etched during formation of the second trenches.
In contrast, amended claim 1 recites depositing a blocking material in the first set of trenches "that protects the first set of trenches from being etched during formation of a second set of trenches," and further recites etching to form the second set of trenches "while the blocking material remains in the first set of trenches." These limitations require that the blocking material protects the first set of trenches during formation of the second set of trenches, such that the first set of trenches are not etched during the formation of the second set of trenches.
However, Applicant cites ¶ [0118] of CHO that includes: “A mask layer ML may be formed on the first surface 100a of the substrate 100 to fill the first trenches 130Ta. Thereafter, second trenches 130Tb may be formed in the substrate 100. The second trenches 130Tb may be formed to cross the first trenches 130Ta. [As] an example, the second trenches 130Tb may be extended in the second direction D2 and may be spaced apart from each other in the first direction D1. The formation of the second trenches 130Tb may include a second mask pattern (not shown) on the mask layer ML to have openings exposing regions, on which the second trenches 130Tb will be formed, and etching the substrate 100 and the mask layer ML using the second mask pattern as an etch mask”.
¶ [0120], teaches: “[0120] Referring to FIGS. 31 and 35A to 35C, the mask layer ML may be removed after the formation of the first and second trenches 130Ta and 130Tb.”.
Removing the blocking material ML of CHO occurred after the formation of the second trenches 130Tb, means the blocking material ML is remained in the first trenches 130Ta when the second trenches 130Tb are formed, hence, protect the first set of trenches from being etched during formation of a second set of trenches. See FIGs. 33-34C.
Thus, CHO’s masking layer ML is indeed, corresponding to the claimed blocking material.
The limitations are met. The rejection is maintained.
Conclusion
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/ANH D MAI/Primary Examiner, Art Unit 2893
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