DETAILED ACTION
Table of Contents
I. Notice of Pre-AIA or AIA Status 3
II. Drawings 3
III. Claim Objections 4
IV. Claim Rejections - 35 USC § 103 5
A. Claims 1, 2, 12, and 13 are rejected under 35 U.S.C. 103 as being unpatentable over WO 2020/054282 as evidenced by US 2021/0351223 (collectively “Nomoto”). 5
B. Claims 3, 7, 8, and 10 are rejected under 35 U.S.C. 103 as being unpatentable over Nomoto in view of US 2018/0301484 (“Vaartstra”). 8
C. Claims 9 and 11 are as being unpatentable over Nomoto in view of Vaartstra, as applied to claim 7 above, and further in view of US 2020/0243579 (“Pyo”). 11
D. Claims 4-6 are rejected under 35 U.S.C. 103 as being unpatentable over Nomoto in view of Vaartstra, as applied to claim 3 above, and further in view of US 2017/0170216 (“Lee”). 12
V. Pertinent Prior Art 15
Conclusion 15
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I. 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 .
II. Drawings
Figs. 3, 7B, 8B, 9B, 10B, 14, and 17 are objected to because there is a feature in each that is not given a reference character. An annotated version of Fig. 9B is reproduced below as one example:
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At least one of Figs. 3, 7B, 8B, 9B, 10B, 14, and 17 should label the above-indicated feature with a reference character.
Moreover, at least Fig. 9A is inconsistent with Fig. 9B, and Fig. 10A is inconsistent with Fig. 10B. In this regard, if Figs. 7A, 8A, 9A, and 10A are showing the back surface of the substrate 2, then Figs. 9A and 10A should not show the gate electrodes 21a, 21b, as evidenced by Figs. 9B and 10B because the gate electrodes are shown to contact the p-type semiconductor region 91a2. On the other hand, if Figs. 7A, 8A, 9A, and 10A are showing the top surface of the substrate 2 then it fails to show each of (1) the p-type semiconductor regions 91a2 and (2) the not-labeled material that surrounds each of the p-type regions 91a2, as evidenced by Figs. 7B, 8B, 9B, and 10B.
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.
III. Claim Objections
Claims 4-11 are objected to because of the following informalities:
In each of claims 4 and 7, replace “an incident side” with “a light incident side” for clarity.
In each of claims 4 and 7, replace “the incident side” with “the light incident side” for clarity.
In each of claims 5, 6, and 8-11, before the period, insert “in plan view” for clarity.
Appropriate correction is required.
IV. Claim Rejections - 35 USC § 103
In the event the determination of the status of the application as subject to AIA 35 U.S.C. 102 and 103 (or as subject to pre-AIA 35 U.S.C. 102 and 103) is incorrect, any correction of the statutory basis for the rejection will not be considered a new ground of rejection if the prior art relied upon, and the rationale supporting the rejection, would be the same under either status.
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.
A. Claims 1, 2, 12, and 13 are rejected under 35 U.S.C. 103 as being unpatentable over WO 2020/054282 as evidenced by US 2021/0351223 (collectively “Nomoto”).
The WO and US publications are in the same patent family. The US publication is used for translation purposes and all citations below are from the US publication.
With regard to claim 1, Nomoto discloses, generally in Figs. 1, 2, and 34,
1. [0] A light-receiving element 1/2 [¶ 52, 56, 184] comprising
[1] a pixel array unit 1/2 in which a plurality of pixels is disposed in an array [¶ 52], the pixels being capable of generating an electrical signal according to light incident from outside [¶ 52], wherein each of the plurality of pixels [¶ 55] include
[2a] a photoelectric conversion region 112 of a first conductivity type [n-type (¶ 57)],
[2b] the photoelectric conversion region 112 photoelectrically converting the light incident [¶ 57],
[3] an inter-pixel separation part 15 that defines an outer edge shape of the pixels, and insulates and separates adjacent the pixels [¶ 58], and
[4a] a pinning region 114 of a second conductivity type [p-type (¶ 57)] that is opposite to the first conductivity type [n-type],
[4b] the pinning region 114 being formed between the photoelectric conversion region 112 and a sidewall of the inter-pixel separation part 15, and
[5] the plurality of pixels is disposed in an array so as to form a honeycomb structure in which corner parts where a plurality of sides intersects are obtuse angles in plan view [¶ 58].
With regard to feature [5] of claim 1, Nomoto does not show the array of pixels arranged in a hexagonal configuration but states that they may be:
The shape of the pixel separation unit 15 is not limited to a rectangular lattice, and may be another topology such as a hexagonal honeycomb lattice.
(Nomoto: ¶ 58; emphasis added)
It would have been obvious to one of ordinary skill in the art, before the effective filing date of the claimed invention, to arrange the pixels in a “hexagonal honeycomb” array because Nomoto explicitly suggests this configuration.
This is all of the limitations of claim 1.
With regard to claim 2, Nomoto further discloses,
2. The light-receiving element according to claim 1, wherein the outer edge shape of the pixels is a regular hexagonal shape.
A “hexagonal honeycomb lattice” is formed by a collection of regular hexagons i.e. hexagons having sides of equal length and 120° angles at the intersection of each side, each hexagon sharing a side with an adjacent hexagon, as evidenced by the Instant Application (Instant Specification; e.g. Figs. 1, 5 and ¶ 38).
With regard to claim 12, Nomoto further discloses,
12. The light-receiving element according to claim 1, wherein the pixel array unit 1/2 further includes an on-chip lens 17 formed for each of the pixels such that the light is condensed on the pixel [¶ 64].
With regard to claim 13, Nomoto further discloses,
13. An electronic apparatus IS, IS1(= 1/2/3) comprising [0] a light-receiving element including
[1] a pixel array unit in which a plurality of pixels is disposed in an array, the pixels being capable of generating an electrical signal according to light incident from outside, wherein each of the plurality of pixels includes
[2a] a photoelectric conversion region of a first conductivity type,
[2b] the photoelectric conversion region photoelectrically converting the light incident,
[3] an inter-pixel separation part that defines an outer edge shape of the pixels, and insulates and separates adjacent the pixels, and
[4a] a pinning region of a second conductivity type that is opposite to the first conductivity type,
[4b] the pinning region being formed between the photoelectric conversion region and a sidewall of the inter-pixel separation part, and
[5] the plurality of pixels is disposed in an array so as to form a honeycomb structure in which corner parts where a plurality of sides intersects are obtuse angles in plan view.
Each of features [0] through [5] has been addressed above, under claim 1. The electronic apparatus includes the substrate 3 with the logic circuit (¶ 54) to form the complete solid-state image sensor IS, IS1.
This is all of the limitations of claim 13.
B. Claims 3, 7, 8, and 10 are rejected under 35 U.S.C. 103 as being unpatentable over Nomoto in view of US 2018/0301484 (“Vaartstra”).
Claim 3 reads,
3. The light-receiving element according to claim 1, wherein each of the plurality of pixels has a dual pixel structure in which the photoelectric conversion region is separated into two by an in-pixel separation part.
The prior art of Nomoto, as explained above, discloses each of the features of claim 1.
Nomoto does not teach the limitations of claim 2.
Vaartstra, like Nomoto, is drawn to a solid-state image sensor having a hexagonally-arranged array of pixels formed by hexagonally-arranged photosensitive regions 110 in Figs. 2A-2C, i.e. photodiodes 502a, 502b in Fig. 5A [¶ 47]) separated by hexagonally-arranged deep trench isolation structures 504, specifically “backside deep trench isolation (“BDTI”) structures” (¶ 47). Vaartstra further teaches that each pixel may be a pixel pair 100 formed under a single lens 102 (¶¶ 26-27) to allow phase-difference auto-focusing (e.g. abstract and ¶¶ 20, 25, 36-42). Fig. 5A of Vaartstra further shows that the pixel pair 502a, 502b in Fig. 5A is separated by a BDTI 504:
Deep trench isolation structures 504 may also be formed within each pixel to physically and electrically isolate the two internal photodiode regions 502a and 502b.
(Vaartstra: ¶ 47; emphasis added)
It would have been obvious to one of ordinary skill in the art, before the effective filing date of the claimed invention, to divide each pixel in Nomoto using a BDTI, in order to enable phase-difference auto-focusing, as taught by Vaartstra (supra). As such, Vaartstra may be seen as an improvement to Nomoto in this aspect. See MPEP 2143.)
This is all of the limitations of claim 3.
Claim 7 reads,
7. The light-receiving element according to claim 3, wherein the in-pixel separation part is a second trench including a metal film or oxide film formed from a surface of an incident side of the pixel to a surface on a side opposite to the incident side.
As explained above, Vaartstra uses the BDTI 504 for the define the hexagonal-shaped pixels as well as the in-pixel separation part to “physically and electrically isolate” (Vaartstra: ¶ 47) the photodiodes, 110, 502a, 502b; therefore, the material used must be electrically insulating. Vaartstra does not, however, give a material for the BDTI.
Vaartstra further teaches that each of the BFTI 604 used to form the hexagonal-shaped pixels as well as the in-pixel separation part are formed from the light-incident surface of the semiconductor substrate 402 toward the opposite surface (Vaartstra: Fig. 7A).
It would have been obvious to one of ordinary skill in the art, before the effective filing date of the claimed invention, to make the in-pixel separation part 504 of Vaartstra, used in Nomoto, by forming a trench from the light-incident surface toward the non-light incident surface because Vaartstra teaches that both of the pixel-defining isolation and in-pixel separate can be made from the light-incident surface.
Then the only difference is that Vaartstra does not give a material of the isolation regions 504.
Nomoto uses an oxide film filled with a light-shielding metal to form the deep trench isolations forming the “pixel separation unit 15” that defines each pixel’s “charge generation region 112”:
The pixel separation unit 15 is provided by covering the inside of the excavated pixel isolation groove with an insulating film and filling the pixel isolation groove with a light-shielding metal such as tungsten (W) via this insulating film. Note that as an insulating film for covering the inside of the pixel separation groove, a “fixed charge film” such as a hafnium oxide film (HfO2 film) may be used, and the pixel separation groove may be filled with an insulating film or the like to form the pixel separation unit 15. As a fixed charge film for forming the pixel separation unit 15, an insulating film containing at least one of oxides of Hf, zirconium (Zr), aluminum (Al), tantalum (Ta), titanium (Ti), magnesium (Mg), yttrium (Y), and a lanthanide element can be used in addition to HfO2.
(Nomoto: ¶ 68; emphasis added )
It would have been obvious to one of ordinary skill in the art, before the effective filing date of the claimed invention, to make the in-pixel separation part of Vaartstra, used in Nomoto, from an oxide filled with light-shielding metal, as taught in Nomoto, because Vaartstra is merely silent as to the material such that one having ordinary skill in the art would use known materials for the same purpose of forming BDTI for pixel definition and in-pixel separation, such as the materials Nomoto is already using for pixel definition. As such, the selection of oxide amounts to obvious material choice. (See MPEP 2144.07.)
This is all of the limitations of claim 7.
With regard to claims 8 and 10, Vaartstra further teaches,
8. The light-receiving element according to claim 7, wherein the second trench is positioned at a center of the pixel and is formed from the center of the pixel toward at least one corner part of the inter-pixel separation part [as shown in Fig. 5A of Vaartstra].
10. The light-receiving element according to claim 7, wherein the second trench is positioned on at least one corner part of the inter-pixel separation part and is formed from the corner part of the inter-pixel separation part toward a center of the pixel [as shown in Fig. 5A of Vaartstra].
It would have been obvious to one of ordinary skill in the art, before the effective filing date of the claimed invention, to configure the in-pixel separation part of Vaartstra used in Nomoto as configured in Vaartstra, i.e. from corner to corner, as shown in Fig. 5A, because Vaartstra teaches that this is a suitable configuration for the in-pixel separation part.
Note that neither of claims 8 and 10, as currently drafted, limit the extent of the in-pixel separation through the pixel, in plan view; therefore, the in-pixel separate part 504 shown in Fig. 5A of Vaartstra meets the literal requirements of claims 8 and 10.
C. Claims 9 and 11 are as being unpatentable over Nomoto in view of Vaartstra, as applied to claim 7 above, and further in view of US 2020/0243579 (“Pyo”).
Claims 9 and 11 read,
9. The light-receiving element according to claim 7, wherein the second trench is positioned at a center of the pixel and is formed from the center of the pixel toward at least one side of the inter-pixel separation part.
11. The light-receiving element according to claim 7, wherein the second trench is positioned on at least one side of the inter-pixel separation part and is formed from the side of the inter-pixel separation part toward a center of the pixel.
The prior art of Nomoto in view of Vaartstra, as explained above, teaches each of the features of claim 7.
The in-pixel separation part of Vaartstra (used in Nomoto) is not configured as required in claims 9 and 11, i.e. between sides of the hexagon, in plan view.
Pyo, like Vaartstra, teaches a dual pixel structure including two photoelectric conversion regions 110a, 110b to enable phase-difference autofocusing (Pyo: ¶¶ 41, 85). Also like Vaartstra, Pyo divides a given pixel architecture by dividing a given pixel into the two photoelectric conversion regions 110a, 110b using one or more in-pixel deep trench isolations (DTIs) 103, 105 formed from the light-incident surface of the substrate toward the non-light-incident surface of the (Pyo: e.g. Figs. 5A, 5E, 6A, 6B; ¶ 86). Pyo shows a variety of configurations of the in-pixel DTIs that including formed from the center toward the side of the pixel in plan view in, e.g. Figs. 5A, 5E, or only from the side toward the center in, e.g. Figs. 12A, 13B, or both in, e.g. Fig. 13B, 15C.
It would have been obvious to one of ordinary skill in the art, before the effective filing date of the claimed invention, to divide the hexagonal pixel region into the dual pixel configuration of Vaartstra, that is used in Nomoto, using an isolation region formed from the center toward a side of the hexagon in plan view, as taught in Pyo in, e.g. Figs. 5A, 5E, or from a side of the hexagon toward the center, as taught in Pyo in, e.g. Figs. 12A, 13B, because it would be the substitution of one known configuration for dividing a pixel region into a dual-pixel configuration for another known configuration, for the purpose same purpose and the same expected result, of allowing phase difference determination of incident light, in order to enable autofocusing. (see MPEP 2143.)
Thus taking Vaartstra and Pyo, it not critical as to whether the in-pixel separation part is directed, i.e. from or toward a side, or from or toward a corner, of a polygon-shaped pixel, in order to divide said pixel into to a dual pixel configuration, because Vaartstra taken with Pyo shows that the dual pixel configuration—no matter how divided—allows phase differences of incident light on said dual pixel to be determined for performing autofocusing.
This is all of the limitations of claim of claims 9 and 11.
D. Claims 4-6 are rejected under 35 U.S.C. 103 as being unpatentable over Nomoto in view of Vaartstra, as applied to claim 3 above, and further in view of US 2017/0170216 (“Lee”).
Claim 4 reads,
4. The light-receiving element according to claim 3, wherein the in-pixel separation part is a first trench including a metal film or oxide film formed from a surface on a side opposite to an incident side of the pixel to the incident side.
The prior art of Nomoto in view of Vaartstra, as explained above, teaches each of the features of claim 3.
As explained above, Vaartstra uses the BDTI 504 for the define the hexagonal-shaped pixels as well as the in-pixel separation part to “physically and electrically isolate” (Vaartstra: ¶ 47) the photodiodes, 110, 502a, 502b; therefore, the material used must be electrically insulating. Vaartstra does not, however, give a material for the BDTI. Vaartstra also shows that the in-pixel separation part 604 is formed from the light-incident side (Vaartstra: Fig. 7A-7C).
Lee, like Vaartstra, teaches a dual pixel structure including two photoelectric converters 144L, 144R to enable phase-difference autofocusing (Lee: ¶¶ 60-62). Also like Vaartstra, Lee teaches that the photoelectric converters 230L, 230R are separated by an isolation region that extends through the thickness of the semiconductor substrate (250 in Fig. 7; ¶¶ 75-77), from the light-incident surface of the substrate toward the non-light-incident surface (251 in Fig. 11; ¶ 93-95), or from the non-light-incident surface toward the light-incident surface (252 in Fig. 12; ¶ 97-98). In addition, Lee teaches that the in-pixel separation 250 may be made from an oxide (¶ 75).
It would have been obvious to one of ordinary skill in the art, before the effective filing date of the claimed invention, to form the in-pixel separation part of Vaartstra used in Nomoto from an oxide filled trench formed from, e.g. the non-light-incident side of the semiconductor substrate 1 in Nomoto, because Lee provides that it is a matter of design choice as to both the surface from which the in-pixel separation part and the extent through said semiconductor substrate. (See MPEP 2143.)
Moreover, as evidenced by instant claim 7, supra, the surface side from which the in-pixel isolation is formed is not critical since Applicant claims that it may be formed from either side of the substrate, as evidenced by at least instant claims 4 and 7.
This is all of the limitations of claim 4.
Claim 5 reads,
5. The light-receiving element according to claim 4, wherein the first trench is positioned at a center of the pixel and is formed from the center of the pixel toward at least one corner part of the inter-pixel separation part.
The limitations of claim 5 have been addressed above under the rejection of claim 8. That discussion is incorporated here.
Claim 6 reads,
6. The light-receiving element according to claim 4, wherein the first trench is positioned at a center of the pixel and is formed from the center of the pixel toward at least one side of the inter-pixel separation part.
As explained above, the in-pixel separation part of Vaartstra (used in Nomoto) is directed toward the corners of the hexagon, in plan view, and is not, consequently, configured as required in claim 6, i.e. toward the sides of the hexagon.
Although Lee teaches a square-shaped pixel, the pixel is divided into a dual pixel configuration using an isolation extending from side to side of the square, in plan view, as shown in Fig. 8 of Lee.
It would have been obvious to one of ordinary skill in the art, before the effective filing date of the claimed invention, to divide the hexagonal pixel region into the dual pixel configuration of Vaartstra, that is used in Nomoto, using an isolation region formed from the center toward the sides of the hexagon in plan view, as taught in Fig. 8 of Lee because it would be the substitution of one known configuration for dividing a pixel region into a dual-pixel configuration for another known configuration, for the purpose same purpose and the same expected result, of allowing phase difference determination of incident light, in order to enable autofocusing. (see MPEP 2143.)
Thus taking Vaartstra and Lee, it is a matter of design choice as to whether the in-pixel separation part is directed, i.e. from or toward a side, or from or toward a corner, of a polygon-shaped pixel, in order to divide said pixel into to a dual pixel configuration, because Vaartstra taken with Lee shows that the dual pixel configuration—no matter how divided—allows phase differences of incident light on said dual pixel to be determined for performing autofocusing.
This is all of the limitations of claim 6.
V. Pertinent Prior Art
The prior art made of record and not relied upon is considered pertinent to applicant's disclosure.
US 2022/0013552 (“Baek”) is cited for disclosing information similar to Vaartstra, i.e. a hexagonal pixel shape (or square) (¶¶ 37, 56, 137, 155) divided into a dual-pixel configuration using an in-pixel isolation structure for the purposes of phase-difference autofocusing (¶ 141).
US 2022/0173139 (“Lee”) is cited for teaching a variety of configurations for an in-pixel isolation structure for dividing a pixel region into a dual-pixel configuration for phase-difference autofocusing (¶¶ 3, 47). See Figs. 3, 12, 21A-21D, 23A-23D, 24A-24D, 25A-25D, and associated text.
Conclusion
Any inquiry concerning this communication or earlier communications from the examiner should be directed to ERIK KIELIN whose telephone number is (571)272-1693. The examiner can normally be reached Mon-Fri: 10:00 AM-7:00 PM.
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Signed,
/ERIK KIELIN/
Primary Examiner, Art Unit 2814