DETAILED ACTION
Allowable Subject Matter
Claim 17 is objected to as being dependent upon a rejected base claim, but would be allowable if rewritten in independent form including all of the limitations of the base claim and any intervening claims.
The following is a statement of reasons for the indication of allowable subject matter. Claim 17 recites the details of (1) the intermediate layers being different thickness and (2) that some of the materials have to be the same between layers. These limitations are not found in the prior art.
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 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 1-16 are rejected under 35 U.S.C. 103 as being unpatentable over (US-2021/0288090) by Li et al (“Li”) in view of (US-2012/0267739) by Katsuno et al (“Katsuno”).
Regarding claim 1, Li discloses in FIG. 2 and related text, e.g., an image sensor, comprising:
a substrate (101) having a first surface (the surface facing micro-lenses 119) and a second surface (the surface facing away from micro-lenses 119) opposing each other;
photodiodes (103) in the substrate;
circuit and wiring structures (105) below the first surface of the substrate;
an insulating structure (107,109) on the second surface of the substrate;
a plurality of color filters (115) on the insulating structure; and
a grid structure (121/123) on the insulating structure, wherein at least a portion of the grid structure is between adjacent color filters of the plurality of color filters (see FIG. 2), wherein the plurality of color filters include a first color filter (115B) and a second color filter (115G) configured to selectively transmit light of different wavelength spectra associated with different colors (blue and green respectively);
wherein the insulating structure includes an anti-reflective layer configured to reduce reflection of light (par. 37 of Li: “The high-k film 107 may have a high-refractive index and a light-absorbing ability”; the “light-absorbing ability”, by definition, would “reduce reflection of light”; similarly, the materials recited for layer 109, in par. 38, are also notoriously well-known to be used as part of “anti-reflective layer”; hence, both layers 107 and 109 would read on the limitations).
Li does not disclose “the anti-reflective layer includes a first region having a first thickness, a second region having a second thickness different from the first thickness, and a boundary region between the first region and the second region, the boundary region vertically overlapping with the first color filter and is horizontally offset from a vertical central axis of the grid structure”.
Katsuno discloses in FIG. 2 and related text, e.g., “the anti-reflective layer includes (116/117; they qualify as “anti-reflective layer”, since Katsuno cites some of the same materials (pars. 53-54) as what Li describes for materials of his layers, as recited in claim 1) includes a first region (very center) having a first thickness, a second region having a second thickness (left and right of center) different from the first thickness, and a boundary region between the first region and the second region (where thickness of 117 changes), the boundary region vertically overlapping with the first color filter (see FIG. 2)”.
It would have been obvious to one of ordinary skill in the art at the time of the invention to modify the device of Li with “the anti-reflective layer includes a first region having a first thickness, a second region having a second thickness different from the first thickness, and a boundary region between the first region and the second region, the boundary region vertically overlapping with the first color filter” as taught by Katsuno, in order to allow for waveguide function (this is the purpose of Katsuno’s structure).
When these specific teachings of Katsuno are applied to device of Li it will result in “and is horizontally offset from a vertical central axis of the grid structure”, since Li’s grid structure is located directly on pixel boundaries, and the Katsuno’s waveguide is located directly in the middle of the pixel; thus meeting limitations, in a combined device.
Examiner’s Note 1: please note that Li, in par. 36 teaches interchangeability of front-side and back-side illuminated imagers. Hence, even though one of the imagers above is FSI (Katsuno), this does not mean that his teachings do not apply to BSI imagers, as Li makes clear.
Examiner’s Note 2: as evidence of Examiner’s assertion and not as prior art, that the layers recited by Li for layer 109 are notoriously well-known for being part of anti-reflective layer, see US-4,514,437, column 5, lines 10-15. Hence, this acts as evidence, by use of an ancient reference in semiconductor industry terms, that the teachings are notoriously well-known.
Regarding claim 2, the combined device of Li and Katsuno disclose in cited figures and related text, e.g., wherein, in the insulating structure, the boundary region between the first region and the second region does not vertically overlap the grid structure (see first FIG. 2 of Katsuno; his “boundary region” is nowhere near the pixel boundary; now see FIG. 2 of Li; his grid structure is right on pixel boundary; thus meeting limitations).
Regarding claim 3, the combined device of Li and Katsuno disclose in cited figures and related text, e.g., wherein the first thickness is smaller than the second thickness (by considering center portion being “second region/second thickness”, and portion to the left and right being “first region/first thickness”, limitations are met), wherein, in the insulating structure, the first region vertically overlaps the first color filter (see FIG. 2 of Katsuno) and does not vertically overlap the second color filter (it is a “region”; “region” can be arbitrarily defined to stop between pixels and not overlap other pixels; thus limitations are met), wherein the first color filter is a blue color filter configured to selectively transmit blue light, and wherein the second color filter is a green color filter configured to selectively transmit green light (Li teaches both blue and green; Katsuno’s structure applies to both blue and green; thus limitations are met).
Regarding claim 4, the combined device of Li and Katsuno disclose in cited figures and related text, e.g., wherein the plurality of color filters further include a third color filter configured to selectively transmit a wavelength spectrum of light that is different from wavelength spectra of light selectively transmitted by either of the first color filter or the second color filter (par. 40 of Li; “red”), wherein the first color filter is a blue color filter configured to selectively transmit blue light (already discussed above), wherein the second color filter is a green color filter configured to selectively transmit green light (already discussed above), wherein the third color filter is a red color filter configured to selectively transmit red light (already discussed above), and wherein, in the insulating structure, the first region vertically overlaps the first color filter (by considering the center portion to be the “first region”, limitations are met), and the second region vertically overlaps each of the grid structure, the second color filter, and the third color filter (the thinner portion spans between all pixels per Katsuno; hence, limitations are met).
Regarding claim 5, the combined device of Li and Katsuno disclose in cited figures and related text, e.g., wherein each color filter of the plurality of color filters vertically overlaps two or more of the photodiodes (see FIG. 1 of Li; there are 4 regions shown; there is red, blue and two green ones; each region covers 4 photodiodes; thus meeting limitations).
Regarding claim 6, the combined device of Li and Katsuno disclose in cited figures and related text, e.g., wherein the grid structure includes a first portion between color filters configured to selectively transmit light of wavelength spectra associated with different colors among the plurality of color filters (121S between 115BS and 115GS), and a second portion (123S) crossing each color filter of the plurality of color filters in a first direction and a second direction perpendicular to the first direction (see FIG. 1; crossing is shown by 123S and it is in two directions perpendicular to each other).
Regarding claim 7, the combined device of Li and Katsuno disclose in cited figures and related text, e.g., wherein the plurality of color filters further include a third color filter configured to selectively transmit a wavelength spectrum of light that is different from wavelength spectra of light selectively transmitted by either of the first color filter or the second color filter, wherein the first color filter is a blue color filter configured to selectively transmit blue light, wherein the second color filter is a green color filter configured to selectively transmit green light, wherein the third color filter is a red color filter configured to selectively transmit red light (all as in claim 4 above), wherein the insulating structure further includes a third region having a third thickness greater than the second thickness (a “boundary region”, but in “third color filter” area), wherein the first region (center region, in this case; thick portion) vertically overlaps at least a portion of the first color filter (red or green), wherein the second region vertically overlaps at least the second color filter and the grid structure (116/117 directly between pixels; so, overlapping both red and green, and thus meeting limitations), and wherein the third region vertically overlaps at least a portion of the third color filter (as defined above, “third region” is in “third filter”, thus meeting limitations).
Regarding claim 8, the combined device of Li and Katsuno disclose in cited figures and related text, e.g., wherein each color filter of the plurality of color filters vertically overlaps two or more of the photodiodes (see FIG. 1 and claim 5).
Regarding claim 9, the combined device of Li and Katsuno disclose in cited figures and related text, e.g., wherein the grid structure includes a first portion between color filters configured to selectively transmit light of wavelength spectra associated with different colors among the plurality of color filters, and a second portion crossing each color filter of the plurality of color filters in a first direction and a second direction perpendicular to the first direction (see claim 6).
Regarding claim 10, the combined device of Li and Katsuno disclose in cited figures and related text, e.g., wherein the color filters further include a third color filter configured to selectively transmit a wavelength spectrum of light that is different from wavelength spectra of light selectively transmitted by either of the first color filter or the second color filter, wherein the first color filter is a blue color filter configured to selectively transmit blue light, wherein the second color filter is a green color filter configured to selectively transmit green light, wherein the third color filter is a red color filter configured to selectively transmit red light (all as in claim 4 above), wherein the insulating structure further includes a third region having a third thickness greater than the second thickness (as in claim 7), wherein the first region vertically overlaps at least a portion of the first color filter, wherein the second region vertically overlaps at least a portion of the second color filter (as in claim 7), and wherein the third region vertically overlaps at least the grid structure and the third color filter (as in claim 7).
Regarding claim 11, the combined device of Li and Katsuno disclose in cited figures and related text, e.g., wherein each of the plurality of color filters vertically overlaps two or more of the photodiodes (as in claim 5).
Regarding claim 12, the combined device of Li and Katsuno disclose in cited figures and related text, e.g., wherein the grid structure includes a first portion between color filters configured to selectively transmit light of wavelength spectra associated with different colors among the plurality of color filters, and a second portion crossing each color filter of the plurality of color filters in a first direction and a second direction perpendicular to the first direction (see claim 6).
Regarding claim 13, the combined device of Li and Katsuno disclose in cited figures and related text, e.g., wherein the insulating structure includes a sequential stack of a lower layer, an intermediate layer and an upper layer (by considering 116/117/118 to be the 3 layers, the limitations are met), wherein the lower layer has a substantially uniform thickness (116), wherein the upper layer has a substantially uniform thickness (118; not specifically stated to be an insulating layer; at the very least obvious to be made of insulating material, in order to prevent electric charge collection), and wherein the intermediate layer (117) includes two or more regions having different thicknesses from each other.
Regarding claim 14, the combined device of Li and Katsuno disclose in cited figures and related text, e.g., an image sensor, comprising:
a substrate having a first surface and a second surface opposing each other (claim 1);
photodiodes in the substrate (claim 1);
circuit and wiring structures below the first surface of the substrate (claim 1);
an insulating structure on the second surface of the substrate (claim 1); and
a plurality of color filters on the insulating structure (claim 1),
wherein the plurality of color filters include a first color filter and a second color filter configured to selectively transmit light of different wavelength spectra associated with different colors (claim 1),
wherein the insulating structure includes an anti-reflective layer configured to reduce reflection of light (see claim 1), and the anti-reflective layer includes a sequential stack of a lower layer, an intermediate layer and an upper layer, wherein the lower layer has a substantially uniform thickness, wherein the upper layer has a substantially uniform thickness, and wherein the intermediate layer includes two or more regions having different thicknesses from each other (claim 13).
Regarding claim 15, the combined device of Li and Katsuno disclose in cited figures and related text, e.g., wherein the intermediate layer includes a first intermediate layer and a second intermediate layer on the first intermediate layer (by considering the layers to be 116-119; limitations are met; 117/118 are the intermediate one), wherein the first intermediate layer (117) includes two or more regions having different thicknesses from each other, and wherein the second intermediate layer (118; not specifically stated to be an insulating layer; at the very least obvious to be made of insulating material, in order to prevent electric charge collection) has a substantially uniform thickness.
Regarding claim 16, the combined device of Li and Katsuno disclose in cited figures and related text, e.g., wherein the intermediate layer includes a first intermediate layer (118) and a second intermediate layer (117) on the first intermediate layer, wherein the second intermediate layer includes two or more regions having different thicknesses from each other (see FIG. 2), and wherein the first intermediate layer has a substantially uniform thickness (see FIG. 2).
Claims 18-20 are rejected under 35 U.S.C. 103 as being unpatentable over (US-2021/0288090) by Li et al (“Li”) in view of (US-2012/0267739) by Katsuno et al (“Katsuno”) as applied to claim(s) above, and further in view of (US-10868070) by Jin et al (“Jin”).
Regarding claim 18, the combined device of Li and Katsuno disclose in cited figures and related text substantially the entire claimed structure as recited in above claims, except “wherein the substrate includes one or more inner sidewall surfaces at least partially defining an opening extending into the substrate from the second surface of the substrate, wherein the lower layer of the insulating structure further includes a portion extending into the opening”.
Jin discloses in FIG. 13 and related text, e.g., “wherein the substrate (100) includes one or more inner sidewall surfaces (contains 150/180) at least partially defining an opening extending into the substrate from the second surface of the substrate (see FIG. 13), wherein the lower layer of the insulating structure (150/180) further includes a portion extending into the opening”.
It would have been obvious to one of ordinary skill in the art at the time of the invention to further modify the device of Li and Katsuno with “wherein the substrate includes one or more inner sidewall surfaces at least partially defining an opening extending into the substrate from the second surface of the substrate, wherein the lower layer of the insulating structure further includes a portion extending into the opening” as taught by Jin, in order to provide DTI type insulation between the pixels.
Regarding claim 19, the combined device of Li, Katsuno and Jin disclose in cited figures and related text, e.g., wherein the second surface of the substrate has an uneven structure (due to DTI presence).
Regarding claim 20, the combined device of Li, Katsuno and Jin disclose in cited figures and related text, e.g., an image sensor, comprising:
a substrate having a first surface and a second surface opposing each other (claim 1);
photodiodes in the substrate (claim 1);
a separation structure between the photodiodes in the substrate (DTI structures of Jin);
circuit and wiring structures below the first surface of the substrate (claim 1);
an insulating structure on the second surface of the substrate (claim 1);
a plurality of color filters on the insulating structure (claim 1); and
a grid structure on the insulating structure, wherein at least a portion of the grid structure is between adjacent color filters of the plurality of color filters, wherein the portion of the grid structure vertically overlaps at least a portion of the separation structure (claim 1),
wherein the plurality of color filters include a blue color filter configured to selectively transmit blue light, a green color filter configured to selectively transmit green light, and a red color filter configured to selectively transmit red light (claim 4), wherein the insulating structure includes an anti-reflective layer configured to reduce reflection of light (see claim 1), and the anti-reflective layer includes a sequential stack of a lower layer, an intermediate layer and an upper layer, wherein the lower layer has a substantially uniform thickness, wherein the upper layer has a substantially uniform thickness, wherein the intermediate layer includes two or more regions having different thicknesses from each other (claim 13),
wherein a minimum thickness of a first portion of the insulating structure vertically overlapping the blue color filter is smaller than a maximum thickness of a second portion of the insulating structure vertically overlapping the red color filter (the thin thickness between pixels when compared to thick thickness in middle of pixel, as was described in claims above), and
wherein the lower surface of the grid structure is flat such that the lower surface of the grid structure at least partially defines a plane extending parallel to at least one of the first surface or the second surface of the substrate (see FIG. 2 of Li).
Response to Arguments
Applicant's arguments have been fully considered but they are not persuasive.
In particular, Applicant’s arguments are addressed within rejection of claim 1. See rejection of claim 1, which recites detailed portions of Li reference, Katsuno reference, and an evidence reference, to support Examiner’s assertions in rejection of claim 1, and addressing Applicant’s arguments.
Conclusion
Additional references (if any) are cited on the PTO-892 as disclosing similar features to those of the instant invention.
THIS ACTION IS MADE FINAL. 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 extension fee 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 Alexander Belousov whose telephone number is (571)-272-3167. The examiner can normally be reached on 10 am-4 pm. If attempts to reach the examiner by telephone are unsuccessful, the examiner's supervisor, Jeff Natalini can be reached on 571-272-2266. The fax phone number for the organization where this application or proceeding is assigned is 571-273-8300.
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/Alexander Belousov/Patent Examiner, Art Unit 2894
05/27/26
/Mounir S Amer/ Primary Examiner, Art Unit 2818
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