Solid-state image sensor

Abstract

Embodiments of the present invention provide a solid-state image sensor. The solid-state image sensor includes a semiconductor substrate having a plurality of photoelectric conversion elements. The photoelectric conversion elements form an N×N pixel array, where N is a positive integer greater than or equal to 3. The solid-state image sensor also includes a modulation layer disposed above the photoelectric conversion elements. The solid-state image sensor further includes a light adjustment structure disposed above the modulation layer and corresponding to the N×N pixel array. The N×N pixel array includes a first pixel region having at least one first pixel. The N×N pixel array also includes a second pixel region adjacent to the first pixel region in a first direction and a second direction different from the first direction, and having a plurality of second pixels. An aperture ratio of the first pixel is different from an aperture ratio of one of the second pixels.

Description

TECHNICAL FIELD

[0001] Embodiments of the present disclosure relate to an image sensor, and more particularly, to a solid-state image sensor having a floating pixel design. BACKGROUND

[0002] Image sensors (e.g., complementary metal-oxidesemiconductor (CMOS) image sensors) have been widely used in various image capturing devices, such as digital still image cameras, digital video cameras, and similar devices. Signal charges can be generated according to the amount of light received in a light-receiving portion (e.g., a photoelectric conversion element) of a solid-state image sensor. In addition, the signal charges generated in the light-receiving portion can be transferred and amplified, thereby obtaining an image signal.

[0003] As image sensors are developed toward small pixels (e.g., pixel size less than 0.7 pm), lower sensitivity can occur due to the small light-receiving area of the small pixels. In a conventional solid-state image sensor, a microlens corresponding to multiple pixels can be used to increase the amount of light, thereby improving quantum efficiency (QE) and / or sensitivity. However, such a structure can easily cause non-uniformity per pixel and increase channel separation.

[0004] In addition, incident light is often concentrated into an isolation structure (e.g., a shallow trench isolation (STI) or a deep trench isolation (DTI)) in a substrate of a conventional solid-state image sensor, which can cause light scattering and degrade image quality. Therefore, there are various challenges to be overcome in the design of a solid-state image sensor. SUMMARY

[0005] In a solid-state image sensor according to some embodiments of the present disclosure, the aperture ratio of different pixel regions can be different, which can optimize light distribution (e.g., prevent incident light from being concentrated into an isolation structure or prevent photoelectric conversion elements from receiving non-uniform light intensity), thereby improving the quality of image signals from the photoelectric conversion elements of the solid-state image sensor.

[0006] According to an embodiment of the disclosure, a solid-state image sensor is provided. The solid-state image sensor includes a semiconductor substrate having a plurality of photoelectric conversion elements. The photoelectric conversion elements form an N×N pixel array, where N is a positive integer greater than or equal to 3. The solid-state image sensor also includes a modulation layer disposed above the photoelectric conversion elements. The solid-state image sensor further includes a light adjustment structure disposed above the modulation layer and corresponding to the N×N pixel array. The N×N pixel array includes a first pixel region having at least one first pixel. The N×N pixel array also includes a second pixel region adjacent to the first pixel region in a first direction and a second direction different from the first direction and having a plurality of second pixels. An aperture ratio of the first pixel is different from an aperture ratio of one of the second pixels.

[0007] In some embodiments, the light adjustment structure is a converging microlens.

[0008] In some embodiments, the solid-state image sensor further includes a grid structure disposed in the modulation layer to divide the modulation layer into a first modulation segment corresponding to the first pixel and a plurality of second modulation segments corresponding to the second pixels. A material of the grid structure includes a transparent dielectric material having a refractive index in a range from 1 to 1.99, or the grid structure is air.

[0009] In some embodiments, a bottom area of the first modulation segment is smaller than a bottom area of one of the second modulation segments.

[0010] In some embodiments, a ratio of the bottom area of the first modulation segment to the bottom area of one of the second modulation segments is less than 0.5, and the first modulation segment is filled with a green, yellow, or transparent material.

[0011] In some embodiments, when the incident light is from a first side of the first modulation segment, an aperture ratio of one of the second modulation segments on a second side opposite to the first side of the first modulation segment is smaller than an aperture ratio of another one of the second modulation segments on the first side of the first modulation segment.

[0012] In some embodiments, the N×N pixel array further includes a third pixel region adjacent to the second pixel region in the first direction and the second direction and having a plurality of third pixels. An aperture ratio of one of the third pixels is different from the aperture ratio of the first pixel and the aperture ratio of one of the second pixels.

[0013] In some embodiments, the grid structure has a first grid width between the first modulation segment and one of the second modulation segments. The grid structure has a second grid width between one of the second modulation segments and one of the third modulation segments. The first grid width is greater than the second grid width.

[0014] In some embodiments, the solid-state image sensor further includes a metal mesh disposed at a bottom of the grid structure.

[0015] In some embodiments, the solid-state image sensor further includes a metal mesh disposed in the modulation layer to divide the modulation layer into a first modulation section and a plurality of second modulation sections. The first modulation section corresponds to the first pixel. The second modulation sections correspond to the second pixels. The metal mesh has a first metal width between one of the first modulation section and the second modulation sections. The metal mesh around the modulation layer has a second metal width. The first metal width is greater than the second metal width.

[0016] In some embodiments, a top area of one of the photoelectric conversion elements corresponding to the first pixel is smaller than a top area of another of the photoelectric conversion elements corresponding to the second pixel.

[0017] In some embodiments, the light adjusting structure is a diverging microlens.

[0018] In some embodiments, a bottom area of the first modulation section is greater than a bottom area of one of the second modulation sections.

[0019] In some embodiments, a top area of one of the photoelectric conversion elements corresponding to the first pixel is greater than a top area of another of the photoelectric conversion elements corresponding to the second pixel.

[0020] In some embodiments, the solid-state image sensor further includes a grid structure disposed in the modulation layer and a color filter layer disposed on the modulation layer. A refractive index of the grid structure is smaller than a refractive index of the modulation layer.

[0021] In some embodiments, the solid-state image sensor further includes an air gap disposed in a space between the grid structure corresponding to the first pixel region and the second pixel region.

[0022] In some embodiments, a ratio of a thickness of the modulation layer to a thickness of the color filter layer is between 0.25 and 1.

[0023] In some embodiments, an aperture ratio in the N x N pixel array varies along a radiation direction of the light adjusting structure.

[0024] In some embodiments, when N = 2n and n is a positive integer, the first pixel region corresponds to four photoelectric conversion elements, and the four photoelectric conversion elements form a P-N junction.

[0025] In some embodiments, the N x N pixel array forms a mosaic pattern, and the mosaic pattern includes an RGB arrangement, a CMY arrangement, or an RYYB arrangement. BRIEF DESCRIPTION OF DRAWINGS

[0026] Embodiments of the present disclosure will be described below in detail with reference to the accompanying drawings. It should be noted that various components are not drawn to scale and are merely intended to illustrate examples. In fact, the sizes of the elements can be enlarged or reduced to clearly show the technical features of the embodiments of the present disclosure.

[0027] FIG. 1 is a partial top view of a solid-state image sensor according to some embodiments of the present disclosure.

[0028] FIG. 2A is a partial cross-sectional view of the solid-state image sensor taken along line A-A' of FIG. 1

[0029] FIG. 2B is a partial cross-sectional view of the solid-state image sensor taken along line B-B' of FIG. 1

[0030] FIG. 2C is a partial cross-sectional view of the solid-state image sensor taken along line A-A' of FIG. 1

[0031] FIG. 2D is a partial cross-sectional view of the solid-state image sensor taken along line A-A' of FIG. 1

[0032] FIG. 2E is a partial cross-sectional view of the solid-state image sensor taken along line A-A' of FIG. 1

[0033] FIG. 2F is a partial cross-sectional view of the solid-state image sensor taken along line A-A' of FIG. 1

[0034] FIG. 2G is a partial cross-sectional view of the solid-state image sensor taken along line A-A' of FIG. 1

[0035] FIG. 2H is a partial cross-sectional view of the solid-state image sensor taken along line A-A' of FIG. 1

[0036] FIG. 2I is a partial cross-sectional view of the solid-state image sensor taken along line A-A' of FIG. 1

[0037] FIG. 2J is a partial cross-sectional view of the solid-state image sensor taken along line A-A' of FIG. 1 ​​​​​​​​​partial cross-sectional view of a solid-state image sensor taken along line A-A' of

[0038] FIG. 2K is a partial cross-sectional view of a solid-state image sensor taken along line A-A' of FIG. 1

[0039] FIG. 3 is a partial top view of a solid-state image sensor according to some embodiments of the disclosure.

[0040] FIG. 4A is a partial cross-sectional view of a solid-state image sensor taken along line C-C' of FIG. 3

[0041] FIG. 4B is a partial cross-sectional view of a solid-state image sensor taken along line C-C' of FIG. 3

[0042] FIG. 4C is a partial cross-sectional view of a solid-state image sensor taken along line C-C' of FIG. 3

[0043] FIG. 3 is a partial top view of a solid-state image sensor according to some embodiments of the disclosure.

[0044] FIG. 4A is a partial cross-sectional view of a solid-state image sensor taken along line D-D' of FIG. 4B

[0045] FIG. 4C is a partial cross-sectional view of a solid-state image sensor taken along line D-D' of FIG. 3

[0046] FIG. 4A-C is a partial cross-sectional view of a solid-state image sensor taken along line D-D' of FIG. 4A

[0047] FIG. 4A is an attention region of an image according to an embodiment of the disclosure.

[0048] FIG. 4A is a partial top view of a solid-state image sensor according to some embodiments of the disclosure.

[0049] FIG. 3 is a partial cross-sectional view of a solid-state image sensor taken along line E-E' of FIG. 3

[0050] ​​​​​​​​FIG. 4A is a partial cross-sectional view of a solid-state image sensor according to some embodiments of the present disclosure.

[0051] FIG. 4A is a partial cross-sectional view of a solid-state image sensor according to some other embodiments of the present disclosure.

[0052] FIG. 3 is a partial plan view of a solid-state image sensor according to an embodiment of the present disclosure.

[0053] FIG. 4B is a partial cross-sectional view of a solid-state image sensor taken along a line F-F’ of FIG. 4B

[0054] FIG. 4B is a partial plan view of a solid-state image sensor according to another embodiment of the present disclosure.

[0055] FIG. 4B is a partial cross-sectional view of a solid-state image sensor taken along a line G-G’ of FIG. 3

[0056] FIG. 4C is a partial plan view of a pixel array of a solid-state image sensor according to some embodiments of the present disclosure.

[0057] FIG. 4C is a partial plan view of a pixel array of a solid-state image sensor according to some other embodiments of the present disclosure.

[0058] FIG. 3 is a partial plan view of a pixel array of a solid-state image sensor according to some other embodiments of the present disclosure.

[0059] Reference signs are as follows:

[0060] 100, 102, 104, 106, 108, 110, 112, 114, 116: solid-state image sensor

[0061] 10: semiconductor substrate

[0062] 11: isolation structure

[0063] 13, 13-4, 13-5, 13-6: photoelectric conversion element

[0064] 20: modulation layer

[0065] 20S1, 20S2, 20S3, 20S4, 20S5, 20S6, 20S11, 20S12, 20S13, 20S14, 20S15: modulation section

[0066] 31, 33, 35: light adjusting structure​​

[0067] 35-1, 35-2, 35-3: sublayer

[0068] 40, 40S1, 40S1', 40S2, 40S2', 40S3, 40S4: mesh structure

[0069] 40G: air gap

[0070] 50, 50S1, 50S2, 50S2', 50S3: metal mesh

[0071] 70: color filter layer

[0072] A5, A6, A7, A10, A11, A13, B2, B3, B4, B5, B6, B8, B9, B12, B14, B15, B18, C1, C3, C4, C7, C9, C11, C13, C15, C16, C17, C19, C23, D2, D4, D6, D10, D16, D20, D22, D24, E1, E5, E21, E25: pixel

[0073] A-A', B-B', C-C', D-D', E-E', F-F', G-G': line

[0074] AJ: P-N junction

[0075] DS2, DS5, DS6, DS13, DS14, DS15: base area

[0076] H A ,H B : thickness

[0077] HI: inner height

[0078] HO: outer height

[0079] LW1, LW2, LW2', LW3, LW4: mesh width

[0080] MW1, MW2, MW2', MW3 metal width

[0081] PA, PA', PA": pixel array

[0082] PA(B): blue pixel array

[0083] PA(C): cyan pixel array

[0084] PA(G): green pixel array

[0085] PA(M): magenta pixel array

[0086] PA(R): red pixel array

[0087] PA(Y): yellow pixel array

[0088] ROI: region of interest

[0089] T4, T5, T6: top area

[0090] X, Y, Z: coordinate axis DETAILED DESCRIPTION

[0091] The following disclosure provides many different embodiments, or examples, for implementing different features of the application. Some examples are described in terms of regions or arrangements of components having particular dimensions relative to each other. Of course, these descriptions are merely examples and are not intended to limit the scope of the application in any way.

[0092] Unless otherwise defined, all terms (including technical and scientific terms) used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this disclosure belongs. It will be further understood that terms, such as those defined in commonly used dictionaries, should be interpreted as having a meaning that is consistent with their meaning in the context of the relevant art and the present disclosure, and will not be interpreted in an overly literal or overly formal sense unless expressly so defined herein.

[0093] FIG. 5 FIG. 1 is a partial top view of a solid-state image sensor 100 according to some embodiments of the present disclosure. FIG. 5 FIG. 2 is a partial cross-sectional view of the solid-state image sensor 100 taken along line A-A’ of FIG. 1. FIG. 6A FIG. 3 is a partial cross-sectional view of the solid-state image sensor 100 taken along line B-B’ of FIG. 1. FIG. 5 FIG. 4 is a partial cross-sectional view of the solid-state image sensor 100 taken along line C-C’ of FIG. 1. FIG. 6B FIG. 5 is a partial cross-sectional view of the solid-state image sensor 100 taken along line D-D’ of FIG. 1. FIG. 5 FIG. 6 is a partial cross-sectional view of the solid-state image sensor 100 taken along line E-E’ of FIG. 1. FIG. 6C FIG. 7 is a partial cross-sectional view of the solid-state image sensor 100 taken along line F-F’ of FIG. 1. FIG. 5 FIG. 8 is a partial cross-sectional view of the solid-state image sensor 100 taken along line G-G’ of FIG. 1.

[0094] In some embodiments, the solid-state image sensor 100 can be a complementary metal-oxide-semiconductor (CMOS) image sensor or a charge coupled device (CCD) image sensor, although embodiments of the present disclosure are not limited thereto.

[0095] It should be noted that FIG. 5 Only one pixel array PA is shown, which includes a pixel CI, a pixel B2, a pixel C3, a pixel B4, a pixel A5, a pixel B6, a pixel C7, a pixel B8, and a pixel C9 corresponding to one light adjusting structure 31. That is, the pixel array PA can be a 3x3 pixel array corresponding to one light adjusting structure 31, and the pixel array PA can correspond to 3x3 photoelectric conversion elements 13 (shown in FIG. 1).FIG. 6A and FIG. 6B ).

[0096] like FIG. 6C As shown, the pixel array PA may include a first pixel region and a second pixel region adjacent to the first pixel region in the X and Y directions. The first pixel region has pixel A5, and the second pixel region has pixels B2, B4, B6, and B8. In some embodiments, the pixel array PA may further include a third pixel region adjacent to the second pixel region in the X and Y directions, the third pixel region having pixels C1, C3, C7, and C9. FIG. 5 As shown, pixels B2 and B8 are positioned above and below pixel A5, respectively, while pixels B4 and B6 are positioned to the left and right of pixel A5, respectively. Furthermore, pixel C1 (or pixel C3, pixel C7, or pixel C9) is arranged diagonally opposite pixel A5.

[0097] Reference FIG. 6A Pixels B2, B4, B6, and B8 can have the same aperture ratio, while pixels C1, C3, C7, and C9 can have the same aperture ratio. However, the aperture ratios of pixel A5, B2 (or B4, B6, or B8), and C1 (or C3, C7, or C9) can be different. FIG. 6A In the illustrated embodiment, the aperture ratio of pixel A5 is less than that of pixel B2 (or pixel B4, pixel B6, or pixel B8), and the aperture ratio of pixel B2 (or pixel B4, pixel B6, or pixel B8) is less than that of pixel C1 (or pixel C3, pixel C7, or pixel C9).

[0098] Reference FIG. 6A and FIG. 6A The solid-state image sensor 100 includes a semiconductor substrate 10 having a plurality of photoelectric conversion elements 13. In some embodiments, the semiconductor substrate 10 may be a wafer or a chip. For example, the semiconductor substrate 10 may contain silicon.

[0099] like FIG. 6A and FIG. 5 As shown, the solid-state image sensor 100 may include an isolation structure 11 disposed in the semiconductor substrate 10. In some embodiments, the isolation structure 11 may include shallow trench isolation (STI) or deep trench isolation (DTI). For example, trenches may be formed in the semiconductor substrate 10 using an etching process, and the trenches may be filled with an insulating or dielectric material to form the isolation structure 11.

[0100] In FIG. 5 With FIG. 6B In the embodiment shown, the isolation structures 11 comprise deep trench isolation (DTI) having the same depth. In some other embodiments, the depth of the isolation structures 11 is variable. That is, the depths of the plurality of isolation structures 11 can be different from one another.

[0101] In some embodiments, the isolation structures 11 can define photoelectric conversion elements 13. That is, the photoelectric conversion elements 13 in the semiconductor substrate 10 can be isolated from one another by the isolation structures 11. In some embodiments, the photoelectric conversion elements 13 can be photodiodes.

[0102] In some embodiments, a high-κ film and / or FIG. 6B With FIG. 5 a buffer layer can be formed over the semiconductor substrate 10 and cover the photoelectric conversion elements 13. For example, the material of the high-κ film can comprise hafnium oxide (HfO2), hafnium tantalum oxide (HfTaO), hafnium titanium oxide (HfTiO), hafnium zirconium oxide (HfZrO), tantalum pentoxide (Ta2O5), other suitable high-κ materials, or combinations thereof, while the material of the buffer layer can comprise silicon oxide, silicon nitride, silicon oxynitride, other suitable insulating materials, or combinations thereof.

[0103] Referring to FIG. 6C With FIG. 5 , the solid-state image sensor 100 comprises a modulation layer 20 disposed above the photoelectric conversion elements 13. In some embodiments, the material of the modulation layer 20 can comprise a dielectric material having a refractive index in a range of about 1.0 to about 2.0.

[0104] In embodiments of the present disclosure, the modulation layer 20 can be used to adjust the intensity of light received by the photoelectric conversion elements 13. In some embodiments, the modulation layer 20 can be a color filter layer, such as a red (R) filter layer, a green (G) filter layer, or a blue (B) filter layer. In some other embodiments, the modulation layer 20 can be a white (W) filter layer, a cyan (C) filter layer, a magenta (M) filter layer, a yellow (Y) filter layer, other suitable filter layers, or combinations thereof.

[0105] In some embodiments, the modulation layer has (or can be divided into) a plurality of modulation segments, such as FIG. 7 the modulation segments 20S4, 20S5, and 20S6 shown, or FIG. 7The modulation sections 20S1, 20S2, and 20S3 are shown. In the present embodiment, each modulation section corresponds to one photoelectric conversion element 13. In some other embodiments, each modulation section can correspond to at least two photoelectric conversion elements 13.

[0106] Referring to FIG. 7 With FIG. 8 The solid-state image sensor 100 includes a light adjustment structure 31 disposed above the modulation layer 20, and the light adjustment structure 31 can correspond to the pixel array PA. That is, the light adjustment structure 31 can correspond to nine pixels (i.e., the pixel C1, the pixel B2, the pixel C3, the pixel B4, the pixel A5, the pixel B6, the pixel C7, the pixel B8, and the pixel C9).

[0107] In some embodiments, the light adjustment structure 31 can be a converging microlens for converging incident light. In some embodiments, the material of the light adjustment structure 31 can include glass, epoxy, silicone resin, polyurethane, other suitable materials, or combinations thereof. For example, the light adjustment structure 31 can be a convex microlens as shown in FIG. 9 With FIG. 8 the light adjustment structure 31 can be a convex microlens as shown in

[0108] Referring to FIG. 8 With FIG. 9 In some embodiments, the solid-state image sensor 100 can include a grid structure 40 disposed in the modulation layer 20. In some embodiments, the material of the grid structure 40 can include a transparent dielectric material having a refractive index in a range of about 1 to about 1.99 (e.g., less than or equal to 1.4), or the grid structure 40 can be air, and the grid structure 40 has a refractive index less than that of the modulation layer 20.

[0109] In some embodiments, the grid structure 40 can divide the modulation layer 20 into a plurality of modulation sections. For example, the grid structure 40 can divide the modulation layer 20 into the modulation section 20S5 (which corresponds to the pixel A5), the modulation section 20S2, the modulation section 20S4, the modulation section 20S6 (which correspond to the pixel B2, the pixel B4, the pixel B6, respectively), and the modulation section 20S1, the modulation section 20S3 (which correspond to the pixel C1, the pixel C3, respectively) as shown in FIG. 8 With FIG. 9 the grid structure 40 can divide the modulation layer 20 into the modulation section 20S5 (which corresponds to the pixel A5), the modulation section 20S2, the modulation section 20S4, the modulation section 20S6 (which correspond to the pixel B2, the pixel B4, the pixel B6, respectively), and the modulation section 20S1, the modulation section 20S3 (which correspond to the pixel C1, the pixel C3, respectively) as shown in

[0110] In the present embodiment, the light adjusting structure 31 is a converging microlens and the light adjusting structure 31 corresponds to the pixel array PA (of nine (3x3) pixels). Due to the light adjusting structure 31 (being converging), the incident light is stronger on the center of the pixel array PA than on the periphery of the pixel array PA. For pixel uniformity, the aperture ratio of each pixel can be adjusted to improve the pixel uniformity.

[0111] As FIG. 10 , FIG. 10 and FIGS. 2A-K illustrated, the grid structure 40 can determine the aperture ratio of each pixel such that the aperture ratio of the pixel A5 is smaller than the aperture ratio of the pixel B2 (or the pixel B4, the pixel B6 or the pixel B8), and the aperture ratio of the pixel B2 (or the pixel B4, the pixel B6 or the pixel B8) is smaller than the aperture ratio of the pixel C1 (or the pixel C3, the pixel C7 or the pixel C9). For example, the grid structure 40 has a grid width LW1 between the modulation section 20S5 and the modulation section 20S4 (or the modulation section 20S6) (i.e., the grid structure 40S1 as illustrated), the grid structure 40 has a grid width LW2 between the modulation section 20S2 and the modulation section 20S1 (or the modulation section 20S3) (i.e., the grid structure 40S2 as illustrated), and the grid width LW1 is greater than the grid width LW2. Further, the grid structure 40 around the modulation layer 20 (i.e., the grid structure 40S3 as illustrated) has a grid width LW3, and the grid width LW2 is greater than the grid width LW3. FIGS. 6A-C FIG. 9 FIGS. 4A-C FIG. 10

[0112] In the embodiment as illustrated in FIG. 11 FIG. 11 , due to the grid width LW1 being greater than the grid width LW2 and the grid width LW2 being greater than the grid width LW3, the base area DS5 of the modulation section 20S5 is smaller than the base area DS6 (or DS2) of the modulation section 20S6 (or 20S2), and the base area DS2 (or DS6) of the modulation section 20S2 (or 20S6) is smaller than the base area DS3 of the modulation section 20S3. Therefore, the aperture ratio of different pixel regions of the solid-state image sensor 100 can be different from each other as illustrated in FIG. 11

[0113] Since the aperture ratio of different pixel regions of the solid-state image sensor 100 can be different, it can optimize the light distribution (e.g., prevent the incident light from concentrating to the isolation structure 11 or prevent the phototransduction element 13 from receiving non-uniform light intensity), thereby improving the quality of the image signal from the phototransduction element 13 of the solid-state image sensor 100.

[0114] FIG. 11 is according to another embodiment of the disclosure along FIG. 12 ​​​​​​A partial cross-sectional view of the solid-state image sensor 100 cut by line A-A'. (Refer to...) FIG. 13 In some embodiments, the solid-state image sensor 100 may include a metal mesh 50 disposed in the modulation layer 20. In some embodiments, the material of the metal mesh 50 may include tungsten (W), aluminum (Al), metal nitrides (e.g., titanium nitride (TiN)), other suitable materials, or combinations thereof.

[0115] In some embodiments, such as FIG. 12 As shown, a portion of the metal mesh 50 (i.e., metal mesh 50S3) may be disposed at the bottom of the mesh structure 40, and the metal mesh 50 divides the modulation layer 20 into multiple modulation segments. For example, the metal mesh 50 divides the modulation layer 20 into modulation segment 20S5 (corresponding to pixel A5), modulation segment 20S2 (corresponding to pixel B2) (not shown in the diagram). FIG. 12 (middle), modulation segment 20S4, modulation segment 20S6 (which correspond to pixels B4 and B6 respectively) and modulation segment 20S1, modulation segment 20S3 (which correspond to pixels C1 and C3 respectively) (not shown in FIG. 13 middle).

[0116] Similarly, in this embodiment, as FIG. 12 and FIG. 12 As shown, the metal mesh 50 can determine the aperture ratio of each pixel, so that the aperture ratio of different pixel regions of the solid-state image sensor 100 can be adjusted as follows: FIG. 12 The two are different from each other. For example, the metal mesh 50 is between modulation segment 20S5 and modulation segment 20S4 (or modulation segment 20S6) (i.e., FIG. 13 The metal mesh 50S1 shown has a metal width MW1, and the metal mesh 50 surrounding the modulation layer 20 (i.e., FIG. 13 The metal mesh 50S3 shown has a metal width MW3, and the metal mesh width MW1 is greater than the metal width MW3.

[0117] Furthermore, in some embodiments, the metal mesh 50 is located between modulation segment 20S2 and modulation segment 20S1 (or modulation segment 20S3) (i.e., not shown in the diagram). FIG. 13 It may have another metal width that is less than the metal width MW1 and greater than the metal width MW3.

[0118] FIG. 13 According to another embodiment of this disclosure, along FIG. 13 A partial cross-sectional view of the solid-state image sensor 100 cut by line A-A'. FIG. 12 The solid-state image sensor 100 shown is similar to FIG. 13 The solid-state image sensor 100 is shown. (And...) FIG. 12One difference in the solid-state image sensor 100 shown is that... FIG. 13 The solid-state image sensor 100 shown may further include a metal mesh 50 disposed at the bottom of the mesh structure.

[0119] Similarly, in this embodiment, as FIG. 13 and FIG. 13 As shown, the mesh structure 40 (including the metal mesh 50 at its bottom) determines the aperture ratio of each pixel, allowing the aperture ratio of different pixel regions of the solid-state image sensor 100 to be adjusted as follows: FIG. 13 The grid widths are different from each other. For example, the grid width LW1 is greater than the grid width LW3, which makes the bottom area DS5 of modulation segment 20S5 smaller than the bottom area DS6 (or DS2) of modulation segment 20S6 (or 20S2).

[0120] FIG. 14 According to another embodiment of this disclosure, along FIG. 15 A partial cross-sectional view of the solid-state image sensor 100 cut by line A-A'. (Refer to...) FIG. 14 In some embodiments, the plurality of photoelectric conversion elements 13 of the solid-state image sensor 100 may be different from each other due to the offset of the isolation structure 11. For example, the position of the isolation structure 11 may be adjusted to form different photoelectric conversion elements 13.

[0121] like FIG. 14 As shown, photoelectric conversion element 13-4 can correspond to pixel B4, photoelectric conversion element 13-5 can correspond to pixel A5, and photoelectric conversion element 13-6 can correspond to pixel B6. In this embodiment, as... FIG. 15 and FIG. 14 As shown, the isolation structure 11 (i.e., the offset of the isolation structure 11) determines the aperture ratio of each pixel, so that the aperture ratio of different pixel regions of the solid-state image sensor 100 can be as follows: FIG. 14 The results shown are different from each other.

[0122] For example, the top area T5 of the photoelectric conversion element 13-5 corresponding to pixel A5 may be smaller than the top area T4 of the photoelectric conversion element 13-4 corresponding to pixel B4 or the top area T6 of the photoelectric conversion element 13-6 corresponding to pixel B6. In some embodiments, the top area T4 of the photoelectric conversion element 13-4 corresponding to pixel B4 (or the top area T6 of the photoelectric conversion element 13-6 corresponding to pixel B6) may be smaller than the photoelectric conversion element (not shown) corresponding to pixel C1 (or pixel C3, pixel C7 or pixel C9). FIG. 14 The top area of ​​).

[0123] FIG. 14 According to some other embodiments of this disclosure, along FIG. 15a sectional view of a portion of the solid-state image sensor 100 taken along the line A-A' of FIG. 14 In the embodiment shown, a bottom area DS4 of the modulation section 20S4 (corresponding to the pixel B4), a bottom area DS5 of the modulation section 20S5 (corresponding to the pixel A5), and a bottom area DS6 of the modulation section 20S6 (corresponding to the pixel B6) can be the same, while the isolation structure 11 (i.e., an offset of the isolation structure 11) can determine the aperture ratio of each pixel, so that the aperture ratios of different pixel regions of the solid-state image sensor 100 can be different from each other as shown in FIG. 15

[0124] As shown in FIG. 14 The mesh structure 40 of the solid-state image sensor 100 can divide the modulation layer 20 into a plurality of modulation sections, as shown in FIG. 15 A portion of the metal mesh 50 can be disposed at the bottom of the mesh structure 40, while another portion of the metal mesh 50 can divide the modulation layer 20 into a plurality of modulation sections, as shown in FIG. 16 The metal mesh 50 of the solid-state image sensor 100 can be disposed at the bottom of the mesh structure 40, while both the mesh structure 40 and the metal mesh 50 can divide the modulation layer 20 into a plurality of modulation sections.

[0125] FIG. 17 is a sectional view of a portion of the solid-state image sensor 100 taken along the line A-A' of FIG. 18 FIG. 1 The solid-state image sensor 100 shown is similar to the solid-state image sensor 100 shown in FIG. 16 and FIG. 17 The mesh structure 40 between the modulation section 20S5 and the modulation section 20S4 (or the modulation section 20S6) (i.e., the mesh structure 40S1 shown in FIG. 18 ) can have a mesh width LW1, the mesh structure 40 (i.e., the mesh structure 40S3 shown in FIG. 3 ) around the pixel array PA (the modulation section 20S4 and the modulation section 20S6) can have a mesh width LW3, and the mesh width LW1 is greater than the mesh width LW3, so that the bottom area DS5 of the modulation section 20S5 (corresponding to the photoelectric conversion element 13-5) is smaller than the bottom area DS6 (or DS4) of the modulation section 20S6 (or 20S4) (corresponding to the photoelectric conversion element 13-6 (or 13-4)). In addition, the isolation structure 11 can be offset, so that the top area T5 of the photoelectric conversion element 13-5 corresponding to the pixel A5 can be smaller than the top area T4 of the photoelectric conversion element 13-4 corresponding to the pixel B4 or the top area T6 of the photoelectric conversion element 13-6 corresponding to the pixel B6.

[0126] ​​Therefore, the isolation structure 11 and the mesh structure 40 can determine the aperture ratio of each pixel, so that the aperture ratio of different pixel regions of the solid-state image sensor 100 can be adjusted as follows: FIG. 5 The light intensity received by the photoelectric conversion elements 13-4, 13-5, and 13-6 is more uniform than that of the pixel B4 or B6.

[0127] FIG. 7 According to another embodiment of this disclosure, along FIG. 8 A partial cross-sectional view of the solid-state image sensor 100 cut by line A-A'. (See attached image.) FIG. 12 As shown, the isolation structure 11 can be like FIG. 14 The isolation structure 11 shown is offset in the same way, and the metal mesh 50 is between modulation segment 20S5 and modulation segment 20S4 (or modulation segment 20S6) (i.e., FIG. 16 The metal mesh 50S1 shown has a metal width MW1, and surrounds the pixel array PA (modulation segment 20S4 and modulation segment 20S6) with a metal mesh 50 (i.e., FIG. 17 The metal mesh 50 (S3) shown has a metal width MW3, and the metal mesh width MW1 is greater than the metal width MW3. In this embodiment, the isolation structure 11 (i.e., the offset of the isolation structure 11) and the metal mesh 50 can determine the aperture ratio of each pixel, so that the aperture ratio of different pixel regions of the solid-state image sensor 100 can be as follows: FIG. 18 The results shown are different from each other.

[0128] FIG. 16 According to another embodiment of this disclosure, along FIG. 17 A partial cross-sectional view of the solid-state image sensor 100 cut by line A-A'. (See attached image.) FIG. 18 As shown, the isolation structure 11 can be like FIG. 16 The isolation structure 11 shown is offset in the same way, and the grid width LW1 is greater than the grid width LW3. In this embodiment, the isolation structure 11 (i.e., the offset of the isolation structure 11) and the grid structure 40 (including the metal grid 50 disposed at its bottom) can determine the aperture ratio of each pixel, so that the aperture ratio of different pixel regions of the solid-state image sensor 100 can be as follows: FIG. 17 The results shown are different from each other.

[0129] FIG. 18 This is a partial top view of a solid-state image sensor 102 according to some embodiments of the present disclosure. ​ According to an embodiment of this disclosure, along ​ A partial cross-sectional view of the solid-state image sensor 102 cut by line C-C'. ​ According to another embodiment of this disclosure, along ​a portion of the solid-state image sensor 102 cut by a line C-C'. ​ is a portion of the solid-state image sensor 102 cut by a line C-C' along ​ a portion of the solid-state image sensor 102 cut by a line C-C'. It should be noted that, for simplicity, ​ , ​ , ​ and ​ some components of the solid-state image sensor 102 can be omitted.

[0130] Similarly, ​ only one pixel array PA is shown, which includes a pixel CI, a pixel B2, a pixel C3, a pixel B4, a pixel A5, a pixel B6, a pixel C7, a pixel B8, and a pixel C9 corresponding to one light adjustment structure 33. That is, the pixel array PA can be a 3x3 pixel array corresponding to one light adjustment structure 33, and the pixel array PA can correspond to 3x3 photoelectric conversion elements 13 (shown in ​ ).

[0131] Referring to ​ , the solid-state image sensor 102 includes a semiconductor substrate 10 having a plurality of photoelectric conversion elements 13. In some embodiments, the solid-state image sensor 102 can include an isolation structure 11 disposed in the semiconductor substrate 10, and the photoelectric conversion elements 13 can be isolated from each other by the isolation structure 11. The solid-state image sensor 102 also includes a modulation layer 20 disposed above the photoelectric conversion elements 13.

[0132] Referring to ​ , the solid-state image sensor 102 includes a light adjustment structure 33 disposed above the modulation layer 20, and the light adjustment structure 33 can correspond to the pixel array PA. That is, the light adjustment structure 33 can correspond to nine pixels (i.e., a pixel CI, a pixel B2, a pixel C3, a pixel B4, a pixel A5, a pixel B6, a pixel C7, a pixel B8, and a pixel C9). In the present embodiment, the light adjustment structure 33 can be a diverging microlens as shown in ​ , and the light adjustment structure 33 can correspond to a pixel array (having nine (3x3) pixels). Due to the (diverging) light adjustment structure 33, the incident light is stronger on the periphery of the pixel array PA than on the center of the pixel array PA. For pixel uniformity, the aperture ratio of each pixel can be adjusted to improve the pixel uniformity.

[0133] As shown in ​ , the pixel B2, the pixel B4, the pixel B6, and the pixel B8 can have the same aperture ratio, while the pixel CI, the pixel C3, the pixel C7, and the pixel C9 can have the same aperture ratio. In ​In the illustrated embodiment, the aperture ratio of pixel A5 is greater than the aperture ratio of pixel B2 (or pixel B4, pixel B6, or pixel B8), and the aperture ratio of pixel C1 (or pixel C3, pixel C7, or pixel C9) is equal to the aperture ratio of pixel A5. For example, as shown in FIG. 1A, the aperture ratio of pixel A5 is greater than the aperture ratio of pixel B2, and the aperture ratio of pixel C1 is equal to the aperture ratio of pixel A5. ​ As shown, the grid width LW1 is greater than the grid width LW3, such that the base area DS5 of the modulation section 20S5 is greater than the base area DS6 of the modulation section 20S6. Further, in some embodiments, the base area of the modulation section 20S1 (corresponding to pixel C1) can be equal to the base area DS5 of the modulation section 20S5.

[0134] In the illustrated embodiment, the grid structure 40 (including the metal grid 50 disposed at the bottom thereof) can determine the aperture ratio of each pixel, such that the aperture ratios of the plurality of pixels can be as shown in FIG. 1A. ​ In some other embodiments, the metal grid 50 or the grid structure 40 without the metal grid 50 can also determine the aperture ratio of each pixel, which is not repeated herein. ​ In the illustrated embodiment, the grid structure 40 (with or without the metal grid 50) has a fixed width, such that the base area DS4 of the modulation section 20S4 (corresponding to pixel B4), the base area DS5 of the modulation section 20S5 (corresponding to pixel A5), and the base area DS6 of the modulation section 20S6 (corresponding to pixel B6) can be equal. Further, the plurality of photoelectric conversion elements 13 of the solid-state image sensor 102 can be different from each other due to the offset of the isolation structure 11. For example, the position of the isolation structure 11 can be adjusted to form different photoelectric conversion elements 13.

[0135] Referring to FIG. 1A, ​ In the illustrated embodiment, the grid structure 40 (with or without the metal grid 50) has a fixed width, such that the base area DS4 of the modulation section 20S4 (corresponding to pixel B4), the base area DS5 of the modulation section 20S5 (corresponding to pixel A5), and the base area DS6 of the modulation section 20S6 (corresponding to pixel B6) can be equal. Further, the plurality of photoelectric conversion elements 13 of the solid-state image sensor 102 can be different from each other due to the offset of the isolation structure 11. For example, the position of the isolation structure 11 can be adjusted to form different photoelectric conversion elements 13.

[0136] As shown, the isolation structure 11 can be offset, such that the top area T5 of the photoelectric conversion element 13-5 corresponding to pixel A5 can be greater than the top area T4 of the photoelectric conversion element 13-4 corresponding to pixel B4 or the top area T6 of the photoelectric conversion element 13-6 corresponding to pixel B6. Thus, the light intensity received by the photoelectric conversion element 13-4, the photoelectric conversion element 13-5, and the photoelectric conversion element 13-6 can be more uniform. Further, in some embodiments, the top area of the photoelectric conversion element corresponding to pixel C1 (not shown in FIG. 1A) can be equal to the top area T5 of the photoelectric conversion element 13-5 corresponding to pixel A5. ​ ​ As shown, the isolation structure 11 can be offset, such that the top area T5 of the photoelectric conversion element 13-5 corresponding to pixel A5 can be greater than the top area T4 of the photoelectric conversion element 13-4 corresponding to pixel B4 or the top area T6 of the photoelectric conversion element 13-6 corresponding to pixel B6. Thus, the light intensity received by the photoelectric conversion element 13-4, the photoelectric conversion element 13-5, and the photoelectric conversion element 13-6 can be more uniform. Further, in some embodiments, the top area of the photoelectric conversion element corresponding to pixel C1 (not shown in FIG. 1A) can be equal to the top area T5 of the photoelectric conversion element 13-5 corresponding to pixel A5.

[0137] In the illustrated embodiment, the grid structure 40 (with or without the metal grid 50) has a fixed width, such that the base area DS4 of the modulation section 20S4 (corresponding to pixel B4), the base area DS5 of the modulation section 20S5 (corresponding to pixel A5), and the base area DS6 of the modulation section 20S6 (corresponding to pixel B6) can be equal. Further, the plurality of photoelectric conversion elements 13 of the solid-state image sensor 102 can be different from each other due to the offset of the isolation structure 11. For example, the position of the isolation structure 11 can be adjusted to form different photoelectric conversion elements 13. ​ In the illustrated embodiment, the grid structure 40 (with or without the metal grid 50) has a fixed width, such that the base area DS4 of the modulation section 20S4 (corresponding to pixel B4), the base area DS5 of the modulation section 20S5 (corresponding to pixel A5), and the base area DS6 of the modulation section 20S6 (corresponding to pixel B6) can be equal. Further, the plurality of photoelectric conversion elements 13 of the solid-state image sensor 102 can be different from each other due to the offset of the isolation structure 11. For example, the position of the isolation structure 11 can be adjusted to form different photoelectric conversion elements 13. ​ In the illustrated embodiment, the grid structure 40 (with or without the metal grid 50) has a fixed width, such that the base area DS4 of the modulation section 20S4 (corresponding to pixel B4), the base area DS5 of the modulation section 20S5 (corresponding to pixel A5), and the base area DS6 of the modulation section 20S6 (corresponding to pixel B6) can be equal. Further, the plurality of photoelectric conversion elements 13 of the solid-state image sensor 102 can be different from each other due to the offset of the isolation structure 11. For example, the position of the isolation structure 11 can be adjusted to form different photoelectric conversion elements 13.

[0138] Referring​​ , the grid structure 40 (with or without the metal grid 50 disposed on the bottom) can have a grid width LW1 and a grid width LW3, and the grid width LW1 is greater than the grid width LW3, such that a bottom area DS5 of the modulation section 20S5 corresponding to the pixel A5 is greater than a bottom area DS6 of the modulation section 20S6 corresponding to the pixel B6; the isolation structure 11 can be offset, such that a top area T5 of the photoelectric conversion element 13-5 corresponding to the pixel A5 can be greater than a top area T4 of the photoelectric conversion element 13-4 corresponding to the pixel B4 or a top area T6 of the photoelectric conversion element 13-6 corresponding to the pixel B6.

[0139] In ​ the illustrated embodiment, the isolation structure 11 (i.e., the offset of the isolation structure 11) and the grid structure 40 (with or without the metal grid 50) can determine the aperture ratio of each pixel, such that the aperture ratios of the plurality of pixels can be as illustrated in ​ .

[0140] ​ is a partial top view of the solid-state image sensor 104 according to some embodiments of the present disclosure. In ​ the illustrated embodiment, the light source can be disposed on the right side of the pixel array PA, such that the incident light can come from the right side of the pixel array PA. In some other embodiments, the light source can be disposed on the left side of the pixel array PA, such that the incident light can come from the left side of the pixel array PA. ​ is a partial cross-sectional view of the solid-state image sensor 104 taken along the line D-D’ of ​ according to an embodiment of the present disclosure. ​ is a partial cross-sectional view of the solid-state image sensor 104 taken along the line D-D’ of ​ according to another embodiment of the present disclosure. ​ is a partial cross-sectional view of the solid-state image sensor 104 taken along the line D-D’ of ​ according to another embodiment of the present disclosure. It should be noted that, for simplicity, ​ , ​ , ​ and ​ some components of the solid-state image sensor 104 can be omitted.

[0141] In ​ the illustrated embodiment, due to the light adjustment structure 31 (converging), the incident light on the leftmost pixel (e.g., the pixel B4) of the pixel array PA (having nine (3x3) pixels) will be stronger than the other pixels (e.g., the pixel A5 and / or the pixel B6). For pixel uniformity, the aperture ratio of each pixel can be adjusted to improve the pixel uniformity.

[0142] For example, as ​As shown, the incident light comes from the right side, the grid structure 40 has a grid width LW2 between the modulation section 20S6 and the modulation section 20S5 (i.e., between the pixel B6 and the pixel A5), and / or the metal grid 50 has a metal width MW2 between the modulation section 20S6 and the modulation section 20S5 (i.e., between the pixel B6 and the pixel A5). ​ As shown, the grid structure 40S2 has a grid width LW2, and / or the metal grid 50 has a metal width MW2 between the modulation section 20S6 and the modulation section 20S5 (i.e., between the pixel B6 and the pixel A5). ​ As shown, the metal grid 50S2 has a metal width MW2, the grid structure 40 has a grid width LW2 between the modulation section 20S5 and the modulation section 20S4 (i.e., between the pixel A5 and the pixel B4), and / or the metal grid 50 has a metal width MW2 between the modulation section 20S5 and the modulation section 20S4 (i.e., between the pixel A5 and the pixel B4). ​ As shown, the grid structure 40S2’ has a grid width LW2’, and / or the metal grid 50 has a metal width MW2’ between the modulation section 20S5 and the modulation section 20S4 (i.e., between the pixel A5 and the pixel B4). ​ As shown, the metal grid 50S2’ has a metal width MW2’, and the grid width LW2’ is greater than the grid width LW2 and / or the metal width MW2’ is greater than the metal width MW2, such that a bottom area DS4 of the modulation section 20S4 corresponding to the pixel B4 is less than a bottom area DS5 of the modulation section 20S5 corresponding to the pixel A5, and the bottom area DS5 of the modulation section 20S5 corresponding to the pixel A5 is less than a bottom area DS6 of the modulation section 20S6 corresponding to the pixel B6.

[0143] That is, the grid structure 40 and / or the metal grid 50 can determine the aperture ratio of each pixel such that the aperture ratio of the pixel B6 (i.e., the pixel located at the right side of the pixel A5) is greater than the aperture ratio of the pixel A5 as shown, and the aperture ratio of the pixel A5 is greater than the aperture ratio of the pixel B4 (i.e., the pixel located at the left side of the pixel A5) as shown. ​ ​

[0144] Referring to FIG. 1, the pixel A1 is located at the left side of the pixel A2, the pixel A2 is located at the right side of the pixel A1, the pixel A3 is located at the left side of the pixel A4, and the pixel A4 is located at the right side of the pixel A3. ​ In the present embodiment, the bottom area DS4 of the modulation section 20S4 corresponding to the pixel B4, the bottom area DS5 of the modulation section 20S5 corresponding to the pixel A5, and the bottom area DS6 of the modulation section 20S6 corresponding to the pixel B6 can be equal, and the isolation structure 11 can be shifted to determine the aperture ratio of each pixel.

[0145] As shown, the top area T4 of the photoelectric conversion element 13-4 corresponding to the pixel B4 can be less than the top area T5 of the photoelectric conversion element 13-5 corresponding to the pixel A5, and the top area T5 of the photoelectric conversion element 13-5 corresponding to the pixel A5 can be less than the top area T6 of the photoelectric conversion element 13-6 corresponding to the pixel B6, such that the aperture ratio of the plurality of pixels can be as shown. ​ ​

[0146] Referring to FIG. 1, the pixel A1 is located at the left side of the pixel A2, the pixel A2 is located at the right side of the pixel A1, the pixel A3 is located at the left side of the pixel A4, and the pixel A4 is located at the right side of the pixel A3. ​ ​​​​In this embodiment, the grid structure 40 (with or without the metal grid 50) can be adjusted such that the base area DS4 of the modulation section 20S4 corresponding to the pixel B4 is smaller than the base area DS5 of the modulation section 20S5 corresponding to the pixel A5, and the base area DS5 of the modulation section 20S5 corresponding to the pixel A5 is smaller than the base area DS6 of the modulation section 20S6 corresponding to the pixel B6. In addition, the isolation structure 11 can be shifted such that the top area T4 of the photoelectric conversion element 13-4 corresponding to the pixel B4 is smaller than the top area T5 of the photoelectric conversion element 13-5 corresponding to the pixel A5, and the top area T5 of the photoelectric conversion element 13-5 corresponding to the pixel A5 is smaller than the top area T6 of the photoelectric conversion element 13-6 corresponding to the pixel B6.

[0147] In this embodiment, the grid structure 40 (with or without the metal grid 50) and the isolation structure 11 can determine the aperture ratio of each pixel such that the aperture ratios of the plurality of pixels can be as shown in ​

[0148] ​ is a region of interest (ROI) of an image according to an embodiment of the present disclosure. Referring to ​ , the region of interest (ROI) can be formed by nine pixel arrays (PAs), and each pixel array (PA) can have nine (3x3) (or more) pixels as shown in the foregoing embodiments. As shown in ​ , the pixel arrays (PAs) can be formed in irregular shapes. For example, the shape of each pixel array (PA) can be modified according to the position of the light spot (LS).

[0149] When the pixel array (PA) is used for phase detection auto focus (PDAF), pixel binning can be used in the pixel array (PA). In some embodiments, at low light intensity, three adjacent pixels can be binned. The PDAF function can be performed by comparing the signal strength of the left pixel with the signal strength of the right pixel or comparing the signal strength of the top pixel with the signal strength of the bottom pixel. In the case of top / bottom, the top can be binned using the pixels C1, B2, and C3, and the bottom can be binned using the pixels C7, B8, and C9. For the case of left / right, the left can be binned using the pixels C1, B4, and C7, and the right can be binned using the pixels C3, B6, and C9. In some embodiments, at medium light intensity, the PDAF function can be performed by comparing the signal strength of the pixel B2 with the signal strength of the pixel B8 (top / bottom) or with the signal strength of the pixel B6 (left / right).

[0150] ​​ is a partial top view of the solid-state image sensor 108 according to some embodiments of the present disclosure.

[0151] ​ is a partial cross-sectional view of the solid-state image sensor 108 taken along the line E-E’ of ​ For simplicity, ​ and ​ some components of the solid-state image sensor 108 can be omitted.

[0152] In some embodiments, the pixel array PA can be designed to be half-shielded to reduce the focus time for PDAF function. As shown in ​ and ​ , the grid structure 40 (including the metal grid 50 disposed at the bottom thereof) between the modulation section 20S5 (corresponding to the pixel A5) and the modulation section 20S6 (corresponding to the pixel B6) or the modulation section 20S4 (corresponding to the pixel B4) (e.g., the grid structures 40S1 and 40S1’) can be adjusted so that the bottom area DS5 of the modulation section 20S5 is smaller than the bottom area DS6 (or DS4) of the modulation section 20S6 (or 20S4). For example, the ratio of the bottom area DS5 of the modulation section 20S5 to the bottom area DS6 (or DS4) of the modulation section 20S6 (or 20S4) can be less than 0.5. In the present embodiment, the modulation section 20S5 can be filled with green material. In some other embodiments, the modulation section 20S5 can be filled with yellow or transparent material to improve the sensitivity in low light environment.

[0153] ​ is a partial cross-sectional view of the solid-state image sensor 110 according to some embodiments of the present disclosure. It should be noted that, for simplicity, ​ some components of the solid-state image sensor 110 can be omitted.

[0154] In the foregoing embodiments, the light adjustment structure can be a spherical microlens (e.g., the light adjustment structure 31 shown in ​ , ​ , ​ the light adjustment structure 33 shown in ​ In some other embodiments, the light adjustment structure can be an asymmetric spherical microlens, or can not be a microlens. As shown in ​As shown, the light adjustment structure 35 of the solid-state image sensor 110 can be a multi-layer structure. In some embodiments, the light adjustment structure 35 can include a sub-layer 35-3 disposed on the modulation layer 20, a sub-layer 35-2 disposed on the sub-layer 35-3, and a sub-layer 35-1 disposed on the sub-layer 35-2. In some embodiments, the refractive index of the sub-layer 35-3 can be greater than the refractive index of the sub-layer 35-2, and the refractive index of the sub-layer 35-2 can be greater than the refractive index of the sub-layer 35-1. The number of sub-layers of the light adjustment structure 35 can be adjusted according to actual needs.

[0155] ​ is a partial cross-sectional view of the solid-state image sensor 112 according to some other embodiments of the present disclosure. It should be noted that, for simplicity, ​ some components of the solid-state image sensor 112 can be omitted.

[0156] Referring to ​ , the solid-state image sensor 112 can have a low-refraction hybrid scheme. That is, the solid-state image sensor 112 can include a color filter layer 70 disposed on the modulation layer 20 to filter light, and the refractive index of the grid structure 40 can be less than the refractive index of the modulation layer 20 to split light. Therefore, the stacked modulation layer 20 and color filter layer 70 can improve channel separation of the modulation section 20S5 (and modulation sections 20S4 and 20S6).

[0157] In some embodiments, the solid-state image sensor 112 can further include an air gap 40G disposed in the grid structure 40. In particular, the air gap 40G can be disposed in the grid structure 40 in a space corresponding to between the first pixel region and the second pixel region or between the second pixel region and the third pixel region (e.g., in the grid structure 40S1 as shown). ​

[0158] In some embodiments, the thickness H A of the modulation layer 20 can be different from the thickness H B of the color filter layer 70. For example, the ratio of the thickness H A of the modulation layer 20 to the thickness H B of the color filter layer 70 can be between about 0.25 and about 1.

[0159] In embodiments of the present disclosure, the pixel array PA can include N x N photoelectric conversion elements, N being a positive integer greater than or equal to 3 (e.g., N = 2n + 1 and n being a positive integer). ​ is a partial top view of the solid-state image sensor 114 according to an embodiment of the present disclosure. ​ is a partial cross-sectional view taken along ​ ​A partial cross-sectional view of the solid-state image sensor 114 cut by line F-F'. It should be noted that, for simplicity, ​ and ​ Some components of the solid-state image sensor 114 may be omitted.

[0160] exist ​ In the illustrated embodiment, the pixel array PA' is a 5×5 pixel array corresponding to 5×5 photoelectric conversion elements. Furthermore, the aperture ratio of each pixel is not shown. ​ In the example, the light adjustment structure 31 can be a converging microlens for converging incident light, and the aperture ratio of each pixel can be varied along the radiation direction of the light adjustment structure 31. Specifically, the aperture ratio of each pixel can increase gradually along the radiation direction of the light adjustment structure 31. ​ In the illustrated embodiment, pixels B8, B12, B14, and B18 may have the same aperture ratio; pixels C3, C7, C9, C11, C15, C17, C19, and C23 may have the same aperture ratio; pixels D2, D4, D6, D10, D16, D20, D22, and D24 may have the same aperture ratio; and pixels E1, E5, E21, and E25 may have the same aperture ratio.

[0161] In some embodiments, such as ​ As shown, the grid structure 40 is located between modulation segment 20S13 and modulation segment 20S12 (or modulation segment 20S14) (i.e., ​ The grid structure 40S2 shown has a grid width LW2, and the grid structure 40 is located between modulation segment 20S12 and modulation segment 20S11 (or between modulation segment 20S14 and modulation segment 20S15) (i.e., ​ The grid structure 40S3 shown has a grid width LW3, while the grid structure 40 surrounding the modulation layer 20 (i.e., ​ The grid structure shown (40S4) has a grid width of LW4. For example... ​ As shown, the grid width LW2 is greater than the grid width LW3, and the grid width LW3 is greater than the grid width LW4.

[0162] Therefore, as ​ and ​ As shown, the bottom area DS13 of the modulation segment 20S13 corresponding to pixel A13 is smaller than the bottom area DS14 of the modulation segment 20S14 corresponding to pixel B14, and the bottom area DS14 of the modulation segment 20S14 corresponding to pixel B14 is smaller than the bottom area DS15 of the modulation segment 20S15 corresponding to pixel C15.

[0163] In the present embodiment, as shown in ​ With ​ reference to FIG. 1, the grid structure 40 (and / or the metal grid 50) can determine the aperture ratio of each pixel such that the aperture ratio of the pixel A13 is less than that of the pixel B8 (or the pixel B12, the pixel B14, or the pixel B18), the aperture ratio of the pixel B8 (or the pixel B12, the pixel B14, or the pixel B18) is less than that of the pixel C3 (or the pixel C7, the pixel C9, the pixel C11, the pixel C15, the pixel C17, the pixel C19, or the pixel C23), the aperture ratio of the pixel C3 (or the pixel C7, the pixel C9, the pixel C11, the pixel C15, the pixel C17, the pixel C19, or the pixel C23) is less than that of the pixel D2 (or the pixel D4, the pixel D6, the pixel D10, the pixel D16, the pixel D20, the pixel D22, or the pixel D24), and the aperture ratio of the pixel D2 (or the pixel D4, the pixel D6, the pixel D10, the pixel D16, the pixel D20, the pixel D22, or the pixel D24) is less than that of the pixel E1 (or the pixel E5, the pixel E21, or the pixel E25).

[0164] Further, in some embodiments, the grid structure 40 (i.e., the grid structure 40S4 shown in ​ ) surrounding the modulation layer 20 can have an outer height HO, and the grid structure 40 between the modulation segments 20S11, 20S12, 20S13, 20S14, 20S15, etc. (i.e., the grid structure 40S2, the grid structure 40S3 shown in ​ ) can have an inner height HI, and the inner height HI is lower than the outer height HO as shown in ​ .

[0165] In some other embodiments of the present disclosure, the pixel array PA can include NxN photoelectric conversion elements, where N=2n and n is a positive integer. ​ is a partial top view of a solid-state image sensor 116 according to another embodiment of the present disclosure. ​ is a partial cross-sectional view of the solid-state image sensor 116 taken along the line G-G’ of ​ . It should be noted that, for simplicity, some components of the solid-state image sensor 116 can be omitted in ​ and ​ .

[0166] In the embodiment shown in ​ , the pixel array PA” is a 4x4 pixel array corresponding to 4x4 photoelectric conversion elements. Further, the aperture ratio of each pixel is not shown in ​For example, the light adjusting structure 31 can be a condensing microlens for condensing incident light, and the aperture ratio of each pixel can vary along the radiation direction of the light adjusting structure 31. In particular, the aperture ratio of each pixel can increase along the radiation direction of the light adjusting structure 31. In the embodiment shown, the pixel B2, the pixel B3, the pixel B5, the pixel B8, the pixel B9, the pixel B12, the pixel B14, and the pixel B15 can have the same aperture ratio, and the pixel C1, the pixel C4, the pixel C13, and the pixel C16 can have the same aperture ratio. ​

[0167] Referring to ​ With ​ In some embodiments, the modulation section 20S6 can correspond to the pixel A6, the pixel A7, the pixel A10, and the pixel A11. In other words, the first pixel region can correspond to four (2x2) photoelectric conversion elements 13. Further, the four photoelectric conversion elements 13 can form the P-N junction AJ.

[0168] In ​ With ​ In the embodiment shown, the grid width LW1 is greater than the grid width LW3. In this embodiment, as ​ With ​ As shown, the grid structure 40 (and / or the metal grid 50) can determine the aperture ratio of each pixel such that the aperture ratio of the pixel A6 (or the pixel A7, the pixel A10, or the pixel A11) is smaller than the aperture ratio of the pixel B5 (or the pixel B2, the pixel B3, the pixel B8, the pixel B9, the pixel B12, the pixel B14, or the pixel B15), and the aperture ratio of the pixel B5 (or the pixel B2, the pixel B3, the pixel B8, the pixel B9, the pixel B12, the pixel B14, or the pixel B15) can be smaller than the aperture ratio of the pixel C1 (or the pixel C4, the pixel C13, or the pixel C16).

[0169] ​ is a partial top view of a pixel array of a solid-state image sensor 100 according to some embodiments of the present disclosure. ​ is a partial top view of a pixel array of a solid-state image sensor 100 according to some other embodiments of the present disclosure. ​ is a partial top view of a pixel array of a solid-state image sensor 100 according to some other embodiments of the present disclosure.

[0170] It should be noted that in some embodiments, the pixel array PA shown can be one of ​ ​ , ​ or ​ In some other embodiments, the pixel array PA shown, ​ ​ ​​​the pixel array PA, ​ the pixel array PA, ​ the pixel array PA, ​ the pixel array PA' or ​ the pixel array PA" can also be ​ , ​ or ​ one of the pixel arrays shown.

[0171] Referring to ​ , ​ and ​ , multiple pixel arrays can form a mosaic pattern. As shown in ​ , the mosaic pattern can include a red pixel array PA(R), a green pixel array PA(G), and a blue pixel array PA(B), which can be referred to as an RGB arrangement. As shown in ​ , the mosaic pattern can include a cyan pixel array PA(C), a magenta pixel array PA(M), and a yellow pixel array PA(Y), which can be referred to as a CMY arrangement. As shown in ​ , the mosaic pattern can include a red pixel array PA(R), a yellow pixel array PA(Y), and a blue pixel array PA(B), which can be referred to as an RYYB arrangement. However, the present disclosure is not limited to the above-mentioned arrangements and colors.

[0172] In summary, according to embodiments of the present disclosure, a solid-state image sensor includes a pixel array, and multiple pixels of each pixel can have different aperture ratios. This can optimize light distribution (e.g., prevent incident light from concentrating to an isolation structure or prevent photoelectric conversion elements from receiving non-uniform light intensity), thereby improving the quality of image signals from photoelectric conversion elements of the solid-state image sensor.

[0173] The components of the above summary of several embodiments are outlined so that those skilled in the art in the technical field of the present disclosure can have a better understanding of the viewpoints of the embodiments of the present disclosure. Those skilled in the art in the technical field of the present disclosure should understand that they can design or modify other processes and structures based on the embodiments of the present disclosure to achieve the same purposes and / or advantages as the embodiments introduced herein. Those skilled in the art in the technical field of the present disclosure should also understand that such equivalent structures do not deviate from the spirit and scope of the present disclosure, and they can make various changes, substitutions, and replacements without departing from the spirit and scope of the present disclosure. Therefore, the scope of protection of the present disclosure is defined by the appended claims. In addition, although the present disclosure has been disclosed as above with several preferred embodiments, it is not intended to limit the present disclosure.

Claims

1. A solid-state image sensor, comprising: A semiconductor substrate has multiple photoelectric conversion elements, and the multiple photoelectric conversion elements form an N×N pixel array, where N is a positive integer greater than or equal to 3; A modulation layer is disposed above the plurality of photoelectric conversion elements; as well as An optical adjustment structure is disposed on the modulation layer, wherein the N×N pixel array shares the optical adjustment structure, and the N×N pixel array includes: A first pixel region having at least one first pixel; A second pixel region is adjacent to the first pixel region in a first direction and in a second direction different from the first direction, and has a plurality of second pixels. Wherein the aperture ratio of at least one first pixel is different from the aperture ratio of one of the plurality of second pixels; and A grid structure is disposed in the modulation layer to divide the modulation layer into a first modulation segment corresponding to the at least one first pixel and a plurality of second modulation segments corresponding to a plurality of second pixels. The bottom area of ​​the first modulation segment is smaller than the bottom area of ​​one of the plurality of second modulation segments, the ratio of the bottom area of ​​the first modulation segment to the bottom area of ​​one of the plurality of second modulation segments is less than 0.5, and the first modulation segment is filled with green, yellow or transparent material.

2. The solid-state image sensor as claimed in claim 1, wherein the light adjustment structure is a converging microlens. The mesh structure is made of a transparent dielectric material having a refractive index in the range of 1 to 1.99, or the mesh structure is made of air.

3. The solid-state image sensor of claim 1, wherein when an incident light comes from a first side of the first modulation segment, the aperture ratio of one of the plurality of second modulation segments located on a second side opposite to the first side of the first modulation segment is less than the aperture ratio of another of the plurality of second modulation segments located on the first side of the first modulation segment.

4. The solid-state image sensor of claim 1, wherein the N×N pixel array further comprises: A third pixel region, adjacent to the second pixel region in the first direction and the second direction, and having multiple third pixels. The aperture ratio of one of the plurality of third pixels is different from the aperture ratio of the at least one first pixel and the aperture ratio of one of the plurality of second pixels. The grid structure has a first grid width between the first modulation segment and one of the plurality of second modulation segments. The grid structure has a second grid width between one of the plurality of second modulation segments and one of the plurality of third modulation segments, and the first grid width is greater than the second grid width.

5. The solid-state image sensor of claim 1, wherein the light adjustment structure is a converging microlens, and the solid-state image sensor further comprises: A metal mesh is disposed in the modulation layer to divide the modulation layer into a first modulation segment corresponding to the at least one first pixel and a plurality of second modulation segments corresponding to a plurality of second pixels. The metal mesh has a first metal width between the first modulation segment and one of the plurality of second modulation segments, and the metal mesh surrounding the modulation layer has a second metal width, wherein the first metal width is greater than the second metal width.

6. The solid-state image sensor of claim 1, wherein when the light adjustment structure is a converging microlens, the top area of ​​one of the plurality of photoelectric conversion elements corresponding to the at least one first pixel is smaller than the top area of ​​the other of the plurality of photoelectric conversion elements corresponding to the plurality of second pixels; and when the light adjustment structure is a diverging microlens, the top area of ​​one of the plurality of photoelectric conversion elements corresponding to the at least one first pixel is larger than the top area of ​​the other of the plurality of photoelectric conversion elements corresponding to the plurality of second pixels.

7. The solid-state image sensor as described in claim 1, The light adjustment structure is a diverging microlens, and the solid-state image sensor also includes: A grid structure is disposed in the modulation layer to divide the modulation layer into a first modulation segment corresponding to the at least one first pixel and a plurality of second modulation segments corresponding to a plurality of second pixels. The material of the mesh structure includes a transparent dielectric material having a refractive index in the range of 1 to 1.99, or the mesh structure is air.

8. The solid-state image sensor of claim 7, wherein the bottom area of ​​the first modulation segment is larger than the bottom area of ​​one of the plurality of second modulation segments, and the solid-state image sensor further comprises: A metal mesh is placed at the bottom of the mesh structure.

9. The solid-state image sensor of claim 7, wherein the N×N pixel array further comprises: A third pixel region, adjacent to the second pixel region in the first direction and the second direction, and having multiple third pixels. The aperture ratio of one of the plurality of third pixels is different from the aperture ratio of the at least one first pixel and the aperture ratio of one of the plurality of second pixels. The grid structure has a first grid width between the first modulation segment and one of the plurality of second modulation segments. The grid structure surrounding the modulation layer has a second grid width, and the first grid width is greater than the second grid width.

10. The solid-state image sensor as claimed in claim 1, The light adjustment structure is a diverging microlens, and the solid-state image sensor also includes: A metal mesh is disposed in the modulation layer to divide the modulation layer into a first modulation segment corresponding to the at least one first pixel and a plurality of second modulation segments corresponding to a plurality of second pixels. The metal mesh has a first metal width between the first modulation segment and one of the plurality of second modulation segments, and the metal mesh surrounding the modulation layer has a second metal width, wherein the first metal width is greater than the second metal width.

11. The solid-state image sensor of claim 1, further comprising: A color filter layer is disposed on the modulation layer; and An air gap is provided in the space between the first pixel region and the second pixel region of the mesh structure. The refractive index of the grid structure is less than that of the modulation layer.

12. The solid-state image sensor of claim 1, further comprising: A color filter layer is disposed on the modulation layer; The refractive index of the grid structure is less than that of the modulation layer, and the ratio of the thickness of the modulation layer to the thickness of the color filter layer is between 0.25 and 1.

13. The solid-state image sensor of claim 1, wherein the aperture ratio in the N×N pixel array varies along the radiation direction of the light-adjusting structure.

14. The solid-state image sensor of claim 1, wherein when N=2n and n is a positive integer, the first pixel region corresponds to four photoelectric conversion elements, and the four photoelectric conversion elements form a PN junction.

15. The solid-state image sensor of claim 1, wherein the N×N pixel array forms a mosaic pattern, and the mosaic pattern includes an RGB arrangement, a CMY arrangement, or an RYYB arrangement.

Images