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 .
Specification
The title of the invention is amended in a curative manner. The objection is withdrawn.
Response to Arguments
Applicant’s arguments, see arguments, filed 3/13/2026, with respect to the rejections of claims 1-16 & 21-24 under 35 U.S.C. § 103 have been fully considered and are somewhat persuasive.
Regarding claim 1, the Applicant argues that the Office has not sufficiently established reasoning to explain why Han’s insulating liner 132 may be interpreted as the claimed metal liner. In response, the Examiner asserts that the term “metal liner” may be interpreted broadly in the context of claim 1, as informed by the as-filed specification, because the as-filed specification recites transition metals (tungsten, cobalt, copper, or ruthenium), or metalloids (aluminum) as possible materials for the metal liner. As-filed specification [0026]. In a similar manner, Han teaches materials for the metal liner (recited as an insulating layer) which include transition metals (hafnium, tantalum) or metalloids (aluminum). The fact that Han labels this layer as an insulating layer is immaterial to the issue because the scope of claim 1 allows for the interpretation of Han presented above and below.
Furthermore, the inclusion of a bonded oxide to the metal element of Han does not exclude it from reading on the metal liner of claim 1 because of the scope of claim 1. In other words, the metal liner comprises a metal material which includes a metal element but may include more elements than just an elemental metal. For the above reasons, it is unreasonable to argue that “no person of ordinary skill in the art would regard any of [hafnium oxide, aluminum oxide, and tantalum oxide] as a metal.” A simple solution would be to amend claim 1 to include “the metal liner substantially comprising one of aluminum, tungsten, ruthenium, cobalt, or copper,” as this proposed amendment would require that the materials include one of these materials to a significant extent which would exclude a material such as aluminum oxide from reading on claim 1.
Regarding Ex-parte Wang, the Applicant attempts to use this PTAB decision to argue that the PTAB would not view a metal oxide as reading on a metal (the Appellant advancing this argument with respect to claims 15 and 17). Ex-parte Wang p. 10. This is not convincing, however, because Jefferson, Arpin, and White overturn the Examiner for the same reason as in claim 1. The reason being that the Examiner relies on the specification, “primarily if not solely” to provide the reason why and how a person of ordinary skill in the art would have made the contested combination. Id. p. 8-9. This reliance amounting to impermissible hindsight bias. Id. p. 9. In other words, the administrative judges do not examine the propriety of interpreting a metal oxide as a metal because they did not, at the time, have to. For this reason, a conclusion that the PTAB agrees that a metal oxide cannot be interpreted as a metal misinterprets the decision. The decision of Ex-parte Wang is entered in the record as non-patent literature.
The Applicant’s arguments concerning claim 6 are persuasive. The rejection is withdrawn.
Regarding claim 7, the Applicant asserts that there is no explanation for the modification of placing a light shielding wall below the pixels. However, the light shielding wall of Asatsuma reduces cross-talk as documented in [0293] of Asatsuma. It is not a stretch for the person of ordinary skill in the art to place cross-talk reducing member in a separate location to further reduce cross-talk in that location. The cross-talk reduction gives the person of ordinary skill in the art a reasonable expectation of success for placing the light shielding wall of Asatsuma in more locations to reduce cross-talk.
Regarding claim 21, the Applicant’s arguments are persuasive.
Regarding claims 10 & 11-16, Applicant’s arguments are persuasive.
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 are rejected under 35 U.S.C. 103 as being unpatentable over Jap. Pat. Pub. No. JP2015023259A, which is of record, to Fukumizu et al. (hereinafter “Fukumizu”) in view of U.S. Pat. Pub. No. US 20200075643 A1 to Han et al. (hereinafter “Han”).
Regarding claim 1, Fukumizu teaches an image sensor (fig. 1), comprising:
a first photodiode (middle light receiving section 13; fig. 1) [0011] disposed between a second photodiode (left light receiving section 13; fig. 1) [0011] and a third photodiode (right light receiving section 13; fig. 1) [0011] along a direction (horizontal direction in fig. 1);
a first deep trench isolation feature (insulating film 41 and light-shielding film 42, hereinafter “deep trench isolation feature,” positioned between the center 13 and left 13) [0026] disposed between the first photodiode (center 13) and the second photodiode (left 13); and
a second DTI feature (furthest right deep trench isolation feature 13) [0026] disposed between the first photodiode (center 13) and the third photodiode (right 13),
a dielectric fill material (insulating film 41) [0026] spaced apart (laterally separated) from the first photodiode (right 13) and the second photodiode (left 13),
wherein a depth of the first DTI feature (center left deep trench isolation feature 13) is greater than a depth of the second DTI feature (furthest right deep trench isolation feature 13).
Fukumizu does not explicitly teach wherein a quantum efficiency of the second photodiode (left 13) is smaller than a quantum efficiency of the first photodiode (center 13).
The courts have held, however, that where the claimed and prior art products are identical or substantially identical in structure or composition, or are produced by identical or substantially identical processes, claimed properties are presumed to be inherent i.e., a prima facie case of anticipation or obviousness has been established. M.P.E.P. 2112.01 (I).
Fukumizu does not teach that the first DTI feature comprises a metal liner to interface the first photodiode and the second photodiode and that the metal liner spaces the fill material from the first and second photodiodes.
Han, however, teaches an image sensor (fig. 10) (abstract) with a first DTI feature (pixel element isolation film 130; fig. 10) [0032] comprising a metal liner (insulating liner 132, comprising a metal oxide) [0033] to interface the first photodiode (PX furthest right; fig. 10) [0025] and the second photodiode (PX second to furthest right), this liner spacing a fill material (134E; fig. 10) from the first (OBX; fig. 10) [0026] and second photodiodes (PX).
It would have been obvious to a person of ordinary skill in the art before the effective filing date of the invention, to modify the structure of Fukumizu with a metal liner and a dielectric fill material spacing the photodiodes apart as required by claim 1 to serve as a negative fixed charge layer (in the case of the metal liner) as taught by Han [0033] and to effectively isolate the photodiodes from one another (in the case of the dielectric fill material) as taught by Han [0090]-[0091].
The Examiner notes that the interpretation of the metal liner follows the Applicant’s as-filed specification. Indeed, because the as-filed specification recites transition metals (tungsten, cobalt, copper, or ruthenium), or metalloids (aluminum) as possible materials for the metal liner, so Han teaches transition metals (hafnium, tantalum) or metalloids (aluminum) for the metal liner. As-filed specification [0026]; Han [0033].
Regarding claim 2, Fukumizu in view of Han does not teach the image sensor of claim 1, wherein a quantum efficiency of the third photodiode is substantially the same as the quantum efficiency of the first photodiode.
The courts have held, however, that where the claimed and prior art products are identical or substantially identical in structure or composition, or are produced by identical or substantially identical processes, claimed properties are presumed to be inherent i.e., a prima facie case of anticipation or obviousness has been established. M.P.E.P. 2112.01 (I).
Regarding claim 3, Fukumizu in view of Han does not explicitly teach the image sensor of claim 1 wherein the first photodiode (center 13) has a first width along the direction (horizontal), wherein the second photodiode (left 13) has a second width along the direction (horizontal), wherein the first width is greater than the second width.
Fukumizu, however, teaches that the width of the trenches, wherein the DTI features are disposed, may be controlled and thus, as a result, control the width of the first and second photodiode.
It would have been obvious to a person of ordinary skill in the art before the effective filing date of the invention, to control the width of the trenches for the DTI features, and by effect, the width of the first and second photodiodes, to control the loading effect of the etching process as taught by Fukumizu [0051]. Given these established conditions, the person of ordinary skill in the art would arrive at the width relationship recited in claim 3 by way of routine experimentation. M.P.E.P. 2144.05 II (A).
Claims 4-6 are rejected under 35 U.S.C. 103 as being unpatentable over Fukumizu in view of Han and further in view of U.S. Pat. Pub. No. US 20210098519 A1 to Hsu et al. (hereinafter “Hsu”).
Regarding claim 4, Fukumizu in view of Han teaches the image sensor of claim 1, further comprising:
a passivation layer (anti-reflection film 50; fig. 1) [0022] disposed over the first photodiode (center 13) the second photodiode (left 13), and the third photodiode (right 13).
Fukumizu in view of Han does not teach a metal grid embedded in the passivation layer and spanning over the first photodiode, the second photodiode and the third photodiode.
Hsu, however, teaches a metal grid (grid segments 116a, 116b, 116c; fig. 1A) [0018] embedded in the first passivation layer (dielectric structure 119; fig. 1A) [0018] and spanning over the first photodiode (104a), the second photodiode (left 104) and the third photodiode (104b).
It would have been obvious to a person of ordinary skill in the art before the effective filing date of the invention to add a metal grid (including its respective position limitations) to reduce pixel cross talk as taught by Hsu [0020]).
Regarding claim 5, Fukumizu in view of Han and Hsu does not teach, as presently modified, the image sensor of claim 4, further comprising: a metal film embedded in the first passivation layer (50) and disposed between the metal grid (Hsu 116 as modified) and the second photodiode (left 13).
Hsu, however, teaches a metal film (light shield structure 118; fig. 1A) [0019] embedded in the first passivation layer (buffer layer 114) and disposed between the metal grid (Hsu 116 as modified) and the second photodiode (104). In other words, the metal film is between the metal grid and the second photodiode 104 at least at a non-orthogonal angle.
It would have been obvious to a person of ordinary skill in the art before the effective filing date of the invention to add a metal film between the grid and the second photo diode to minimize blooming as taught by Hsu [0020].
Claim 7 is rejected under 35 U.S.C. 103 as being unpatentable over Fukumizu in view of Han, as applied to claim 6 above, and further in view of W.O. Pat. Pub. No. WO 2021124964 A1 to Asatsuma et al. (hereinafter “Asatsuma”).
Regarding claim 7, Fukumizu teaches wherein the first metal structure (30) is spaced apart from the first DTI feature (center left 13) by the first dielectric layer (first dielectric layer).
Fukumizu does not teach the image sensor of claim 6, wherein the first metal structure (30) has a ring shape and extends completely around a portion of the second dielectric layer (33) directly below the second photodiode (left 13).
Asatsuma, however, teaches that metal structures (light-shielding wall 350; fig. 34) [0268] which have ring-like shapes (fig. 34) may be used to surround pixels [0268] to reduce cross-talk [0004]. This teaching of Asatsuma gives the person of ordinary skill in the art a reasonable expectation of success regarding the shape of the first metal structure. And although the metal structure of Asatsuma is disposed above a photodiode, the POSITA would have a reasonable expectation of success regarding a metal structure being disposed below the photodiodes to reduce cross-talk below. It thus would have been obvious to a person of ordinary skill in the art before the effective filing date of the invention to modify the first metal structure of Fukumizu to comprise a ring shape to reduce cross talk as taught by Asatsuma [0004] & [0268]. The metal structure of Asatsuma being cross-talk reducing members which may be used to reduce cross-talk wherever needed.
Claims 8 & 9 are rejected under 35 U.S.C. 103 as being unpatentable over Fukumizu in view of Han, as applied to claim 6 above, and further in view of U.S. Pat. Pub. No. US 20220093665 A1 to Park et al. (hereinafter “Park”).
Regarding claim 8, Fukumizu in view of Han does not teach the image sensor of claim 6, further comprising:
a second etch stop layer disposed below the second dielectric layer;
a third dielectric layer dispose below the second etch stop layer; and
a second metal structure embedded in the second etch stop layer and the third dielectric layer,
wherein the second metal structure is disposed directly below the second photodiode,
wherein a vertical projection area of the second metal structure is greater than a vertical projection area of the second photodiode, wherein the first metal structure is in direct contact with the second metal structure.
Park, however, teaches an image sensor further comprising:
a second etch stop layer (wiring dielectric layer 222; fig. 11) [0048] disposed below the second dielectric layer (wiring dielectric layer 221; fig. 11) [0048];
a third dielectric layer (wiring dielectric layer 223; fig. 11) [0048] dispose below the second etch stop layer (222); and
a second metal structure (wiring vias and lines 211 and 213; fig. 11) [0048] embedded in the second etch stop layer (222) and the third dielectric layer (223),
wherein the second metal structure (211 and 213) is disposed directly below the second photodiode (photoelectric conversion 110b; fig. 13),
wherein a vertical projection area (projection if viewed from D3; fig. 11) of the second metal structure (211 and 213) is greater than a vertical projection area of the second photodiode (110b),
wherein the first metal structure (211 of layer 221) is in direct contact with the second metal structure (211 and 213).
It would have been obvious to a person of ordinary skill in the art before the effective filing date of the invention, to add a second metal structure (including its position limitations), a second etch stop layer, & third dielectric layer dielectric layer (including its position limitations) to the image sensor of Fukumizu in view of Han to facilitate signal processing of the photoelectric regions as taught by Park [0049]; the second metal structure having a larger vertical projection (than 110b) to allow for connection to more photoelectric conversion regions as taught by Park [0049].
Regarding claim 9, Fukumizu in view of Han and Park teaches the image sensor of claim 6, wherein the first metal structure (30) comprises an array of metal posts (fig. 1) surrounding a rectangular vertical projection area (fig. 2) of the second photodiode (13; this element being disposed beneath 20(22) and 20(21) in fig. 2).
Allowable Subject Matter
Claim 6 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.
Claims 10-16 & 21-24 allowed. The claims are allowed because the amendments to each of claim 10 and 21 distinguish these claims over any found reference available. Claims 11-16 and 22-24 are allowable by virtue of their dependence on an allowable claim.
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 ETHAN EDWARD CUTLER whose telephone number is (703)756-5415. The examiner can normally be reached Monday-Friday 7:30 am - 5:00 pm Eastern Time.
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, N. Drew Richards can be reached on (571) 272-1736. 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.
/ETHAN EDWARD CUTLER/Examiner, Art Unit 2892
/NORMAN D RICHARDS/Supervisory Patent Examiner, Art Unit 2892