solid-state image sensor

Abstract

This invention provides a solid-state image sensor. The solid-state image sensor includes multiple photoelectric conversion elements. It also includes a first color filter layer and a second color filter layer, with the first color filter layer disposed above the photoelectric conversion elements and the second color filter layer adjacent to it, each having multiple first color filter segments and second color filter segments. Furthermore, the solid-state image sensor includes a first metal mesh structure disposed between the first and second color filter layers. It also includes a second metal mesh structure disposed between the first and second color filter segments. The bottom of the first metal mesh structure has a first mesh width, and the bottom of the second metal mesh structure has a second mesh width smaller than the first mesh width.

Description

Technical Field

[0001] This disclosure relates to an image sensor, and more particularly to a solid-state image sensor comprising a metal mesh structure having different mesh heights. Background Technology

[0002] Solid-state image sensors (e.g., charge-coupled device (CCD) image sensors, complementary metal-oxide-semiconductor (CMOS) image sensors, etc.) are widely used in various imaging devices, such as digital still cameras, digital video cameras, and similar devices. In a solid-state image sensor, the light-sensing portion can be formed at each of multiple pixels, and a signal charge can be generated based on the amount of light received in the light-sensing portion. Furthermore, the signal charge generated in the light-sensing portion can be transmitted and amplified to obtain an image signal.

[0003] In recent years, in order to increase the number of pixels to provide high-resolution images, the trend in image sensors, especially CMOS image sensors, has been to reduce pixel size. However, as pixel size continues to decrease, various challenges remain in the design and manufacturing of image sensors.

[0004] For example, obliquely incident light directly radiating into a solid-state image sensor can be divided into reflected light and transmitted light. However, when this reflected and transmitted light enters a color filter segment with different colors at adjacent pixels, the reflected and transmitted light will have different energies. This difference in energy between the reflected and transmitted light will produce different signal intensities at adjacent pixels with the same color; this phenomenon is called channel separation. Channel separation will lead to a deterioration in image detection performance. Summary of the Invention

[0005] In some embodiments of this disclosure, the solid-state image sensor includes a metal mesh structure with different mesh widths, which can improve channel separation, thereby improving the quality of the image signal from the photoelectric conversion element of the solid-state image sensor.

[0006] According to some embodiments of this disclosure, a solid-state image sensor is provided. The solid-state image sensor includes a plurality of photoelectric conversion elements. The solid-state image sensor also includes a first color filter layer disposed above the photoelectric conversion elements and having a plurality of first color filter segments. The solid-state image sensor further includes a second color filter layer disposed above the photoelectric conversion elements and adjacent to the first color filter layer, and having a plurality of second color filter segments. Furthermore, the solid-state image sensor includes a first metal mesh structure disposed between the first color filter layer and the second color filter layer. The solid-state image sensor also includes a second metal mesh structure disposed between the first color filter segments and between the second color filter segments. The bottom of the first metal mesh structure has a first mesh width, and the bottom of the second metal mesh structure has a second mesh width, wherein the second mesh width is smaller than the first mesh width.

[0007] In some embodiments, the first color filter segment includes a plurality of green filter segments, while the second color filter segment includes a plurality of blue / red filter segments.

[0008] In some embodiments, the bottom of the second metal mesh structure between the green filter segments has a green mesh width, and the bottom of the second metal mesh structure between the blue / red filter segments has a blue / red mesh width, the blue / red mesh width being different from the green mesh width.

[0009] In some embodiments, the difference between the width of the green grid and the width of the blue / red grid is between 0 and 50 nm.

[0010] In some embodiments, the solid-state image sensor further includes a partitioned grid structure disposed on the first metal grid structure and the second metal grid structure. In a cross-section of the solid-state image sensor, the partitioned grid structure is divided into multiple partitioned grid segments.

[0011] In some embodiments, the partitioned grid structure has a partitioned grid width that is greater than or equal to a first grid width.

[0012] In some embodiments, in the edge region of the solid-state image sensor, the second metal mesh structure has an offset relative to the center line of the corresponding dividing mesh segment.

[0013] In some embodiments, the offset is variable.

[0014] In some embodiments, in the edge region of the solid-state image sensor, the second metal mesh structure between the green filter segments has a first offset relative to the center line of each dividing mesh segment, and the second metal mesh structure between the blue / red filter segments has a second offset relative to the center line of each dividing mesh segment, and the first offset is different from the second offset.

[0015] In some embodiments, the difference between the first offset and the second offset is between 0 and 50 nm.

[0016] In some embodiments, in the horizontal direction, the second metal mesh structure is offset toward the side away from the incident light.

[0017] In some embodiments, a first color filter layer or a second color filter layer covers a portion of the second metal mesh structure.

[0018] In some embodiments, photoelectric conversion elements are arranged to correspond to a plurality of phase detection autofocus pixels, a plurality of first regular pixels surrounding the phase detection autofocus pixels, and a plurality of second regular pixels surrounding the first regular pixels.

[0019] In some embodiments, the first metal mesh structure is disposed in the region between the phase detection autofocus pixel and the first normal pixel, while the second metal mesh structure is disposed in the region between the first normal pixel and the second normal pixel.

[0020] In some embodiments, the first metal mesh structure has a first mesh height, the second metal mesh structure has a second mesh height, and the second mesh height is lower than the first mesh height.

[0021] In some embodiments, in a cross-sectional view of the solid-state image sensor, the first metal mesh structure and the second metal mesh structure are formed as trapezoids, triangles, or rectangles.

[0022] In some embodiments, the solid-state image sensor further includes a plurality of light-focusing structures disposed on the first color filter layer and the second color filter layer.

[0023] In some embodiments, the thickness of the light-concentrating structure varies.

[0024] In some embodiments, the ratio of the second grid width to the first grid width is between 0.25 and 0.9.

[0025] The beneficial effect of the present invention is that, compared with the conventional mesh structure with a fixed metal mesh width, the solid-state image sensor of the present disclosure includes a first metal mesh structure and a second metal mesh structure with different widths, which can improve channel separation, thereby improving the quality of the image signal from the photoelectric conversion element of the solid-state image sensor. Attached Figure Description

[0026] The embodiments of this disclosure will be described in detail below with reference to the accompanying drawings. It should be noted that the various feature components are not drawn to scale and are only used for illustrative purposes. In fact, the dimensions of the components may be enlarged or reduced to clearly show the technical features of the embodiments of this disclosure.

[0027] Figure 1 This is a top view showing a solid-state image sensor according to an embodiment of the present disclosure.

[0028] Figure 2 Is it displayed along Figure 1 A cross-sectional view of the solid-state image sensor cut by section line A-A'.

[0029] Figure 3 Is it displayed along Figure 1 A cross-sectional view of the solid-state image sensor cut by section line B-B'.

[0030] Figure 4 It corresponds to Figure 2 Another cross-sectional view of the solid-state image sensor.

[0031] Figure 5 It corresponds to Figure 3 Another cross-sectional view of the solid-state image sensor.

[0032] Figure 6 This is a cross-sectional view showing a solid-state image sensor according to another embodiment of the present disclosure.

[0033] Figure 7 This is a cross-sectional view showing a solid-state image sensor according to another embodiment of the present disclosure.

[0034] Figure 8 It corresponds to Figure 7 Another cross-sectional view of the solid-state image sensor.

[0035] Figure 9 This is a cross-sectional view showing a solid-state image sensor according to an embodiment of the present disclosure.

[0036] Figure 10 This is a cross-sectional view showing a solid-state image sensor according to an embodiment of the present disclosure.

[0037] Figure 11 This is a cross-sectional view showing a solid-state image sensor according to another embodiment of the present disclosure.

[0038] Figure 12 This is a cross-sectional view showing a solid-state image sensor according to an embodiment of the present disclosure.

[0039] The attached figures are labeled as follows:

[0040] 10, 12, 14, 16, 18, 20, 22: Solid-state image sensors

[0041] 101: Semiconductor substrate

[0042] 101F: Front surface

[0043] 101B: Backside surface

[0044] 103: Photoelectric conversion element

[0045] 105: Wiring Layer

[0046] 107: High dielectric constant film

[0047] 109: Buffer layer

[0048] 111,111',111”: First metal mesh

[0049] 113,113',113”,113B,113B',113G,113G',113R: Second metal mesh structure

[0050] 115B: Blue filter layer

[0051] 115BS: Blue filter section

[0052] 115G: Green Filter Layer

[0053] 115GS: Green filter section

[0054] 115R: Red filter layer

[0055] 115RS: Red filter section

[0056] 117: Transparent layer

[0057] 119: Concentrating structure

[0058] 119-1: First focusing structure

[0059] 119-2: Second focusing structure

[0060] 121: Divided Grid Structure

[0061] 121S: Separate grid sections

[0062] 121W: Grid width

[0063] D: Horizontal direction

[0064] dB, dB', dG, dG', dR: Offset

[0065] L: Incident light

[0066] MH1: First grid height

[0067] MHR,MHG: Second grid height

[0068] ML1: First thickness

[0069] ML2: Second thickness

[0070] MW1: First grid width

[0071] MW2: Second grid width

[0072] MWB: Blue grid width

[0073] MWG: Green grid width

[0074] MWR: Red grid width

[0075] P1: First normal pixel

[0076] P2: Second normal pixel

[0077] PDAF: Phase Detection Autofocus Pixel

[0078] A-A': Section line

[0079] B-B': Section line Detailed Implementation

[0080] The following disclosure provides many different embodiments or examples to implement the various features of this application. The following disclosure describes specific examples of the various components and their arrangements to simplify the explanation. Of course, these specific examples are not intended to be limiting. For example, if the embodiments of this disclosure describe a first feature formed on or above a second feature, it means that it may include embodiments where the first feature and the second feature are in direct contact, or it may include embodiments where an additional feature is formed between the first feature and the second feature, so that the first feature and the second feature may not be in direct contact.

[0081] It should be understood that additional operational steps may be performed before, during, or after the method, and in other embodiments of the method, some operational steps may be replaced or omitted.

[0082] Furthermore, spatially related terms may be used, such as "below," "below," "lower," "above," "above," "higher," and similar terms. These spatially related terms are used to facilitate the description of the relationship between one or more elements or features in the illustrations and to one or more other elements or features. These spatially related terms include different orientations of the device in use or operation, as well as the orientations described in the accompanying drawings. When the device is turned to a different orientation (rotated 90 degrees or other orientations), the spatially related adjectives used will also be interpreted according to the orientation after the turn.

[0083] In instruction manuals, the terms "about," "approximately," and "roughly" typically indicate within 20%, 10%, 5%, 3%, 2%, 1%, or 0.5% of a given value or range. The given quantity is an approximate quantity; that is, even without specific mention of "about," "approximately," or "roughly," the meaning of "about," "approximately," or "roughly" can still be implied.

[0084] Unless otherwise defined, all terms used herein (including technical and scientific terms) have the same meaning as commonly understood by those skilled in the art to which this disclosure pertains. It is understood that these terms, such as those defined in commonly used dictionaries, should be interpreted as having a meaning consistent with the relevant art and the background or context of this disclosure, and should not be interpreted in an idealized or overly formal manner, unless specifically defined in embodiments of this disclosure.

[0085] The different embodiments disclosed below may reuse the same reference numerals and / or designations. These repetitions are for the purpose of simplicity and clarity and are not intended to limit the specific relationship between the different embodiments and / or structures discussed.

[0086] Based on the direction of light incident on the light-receiving unit, solid-state image sensors can be broadly classified into two types: front-side illuminated (FSI) image sensors, which receive light incident on the front side of the semiconductor substrate, where a wiring layer for the readout circuit is formed; and back-side illuminated (BSI) image sensors, which receive light incident on the back side of the semiconductor substrate, where no wiring layer is formed. For color image imaging, color filter layers are provided in both FSI and BSI image sensors.

[0087] Figure 1 This is a top view showing a solid-state image sensor 10 according to an embodiment of the present disclosure. Figure 2 Is it displayed along Figure 1A cross-sectional view of the solid-state image sensor 10 cut by the section line A-A' in the figure. Figure 3 Is it displayed along Figure 1 The image shows a cross-sectional view of the solid-state image sensor 10 cut by section line B-B'. It should be noted that, for the sake of simplicity... Figures 1 to 3 Some components of the image sensor 10 may be omitted.

[0088] In some embodiments, the solid-state image sensor 10 may be a complementary metal-oxide-semiconductor (CMOS) image sensor or a charge-coupled device (CCD) image sensor, but the embodiments disclosed herein are not limited thereto. Figure 2 and Figure 3 As shown, the solid-state image sensor 10 includes a semiconductor substrate 101, which may be, for example, a wafer or a chip, but is not limited thereto in this disclosure. The semiconductor substrate 101 has a front surface 101F and a back surface 101B opposite to the front surface 101F. A plurality of photoelectric conversion elements 103 (e.g., photodiodes) may be formed in the semiconductor substrate 101.

[0089] In some embodiments, the photoelectric conversion elements 103 in the semiconductor substrate 101 are isolated from each other via an isolation structure (not shown), such as a shallow trench isolation (STI) region or a deep trench isolation (DTI) region. Trenches can be formed in the semiconductor substrate 101 using an etching process, and the trenches can be filled with an insulating or dielectric material to form the isolation structure.

[0090] In some embodiments, the photoelectric conversion element 103 is formed on the back surface 101B of the semiconductor substrate 101, and the wiring layer 105 is formed on the front surface 101F of the semiconductor substrate 101, but this disclosure is not limited thereto. The wiring layer 105 may be an interconnect structure containing multiple wires and vias buried in multiple dielectric layers, and the wiring layer 105 may further contain various circuits required by the solid-state image sensor 10. Incident light can illuminate the back surface 101B and be received by the photoelectric conversion element 103.

[0091] Figure 2 and Figure 3 The solid-state image sensor 10 shown may be referred to as a back-illuminated (BSI) image sensor, but this disclosure is not intended to limit it. In some other embodiments, the solid-state image sensor may be a front-illuminated (FSI) image sensor. For an FSI image sensor, Figure 2 and Figure 3The semiconductor substrate 101 and wiring layer 105 shown can be flipped up and down. In the FSI image sensor, incident light shines on the side of the front surface 101F, passes through the wiring layer 105, and is then received by the photoelectric conversion element 103 formed on the back surface 101B of the semiconductor substrate 101.

[0092] like Figure 2 and Figure 3 As shown, in some embodiments, the solid-state image sensor 10 may also include a high-k dielectric film 107 formed on the back surface 101B of the semiconductor substrate 101 and covering the photoelectric conversion element 103. The material of the high-k dielectric film 107 may include hafnium oxide (HfO2), hafnium tantalum oxide (HfTaO), hafnium titanium oxide (HfTiO), hafnium zirconium oxide (HfZrO), tantalum pentoxide (Ta2O5), or other suitable high-k dielectric materials, but this disclosure is not limited to these. The high-k dielectric film 107 may be formed by a deposition process. The deposition process may be, for example, chemical vapor deposition (CVD), plasma-enhanced chemical vapor deposition (PECVD), atomic layer deposition (ALD), or other deposition techniques. The high-k dielectric film 107 may have a high refractive index and light absorption capability.

[0093] like Figure 2 and Figure 3 As shown, in some embodiments, the solid-state image sensor 10 may further include a buffer layer 109 formed on a high-dielectric-constant film 107. The material of the buffer layer 109 may include silicon oxide, silicon nitride, silicon oxynitride, other suitable insulating materials, or combinations thereof, but this disclosure is not limited thereto. The buffer layer 109 may be formed by a deposition process. Deposition processes include, for example, spin coating, chemical vapor deposition, flowable chemical vapor deposition (FCVD), plasma-enhanced chemical vapor deposition, physical vapor deposition (PVD), or other deposition techniques.

[0094] Reference Figures 1 to 3The solid-state image sensor 10 includes a green filter layer 115G, a blue filter layer 115B, and a red filter layer 115R, which are disposed above the photoelectric conversion element 103. More specifically, the green filter layer 115G has multiple green filter segments 115GS, the blue filter layer 115B has multiple blue filter segments 115BS, and the red filter layer 115R has multiple red filter segments 115RS.

[0095] In some embodiments, the blue filter layer 115B is as follows: Figure 1 and Figure 2 The red filter layer 115R is positioned adjacent to the green filter layer 115G, as shown. Figure 1 and Figure 3 The solid-state image sensor 10 is shown positioned adjacent to the green filter layer 115G, but this embodiment is not limited thereto. In some other embodiments, the solid-state image sensor 10 may also include a white filter layer or a yellow filter layer.

[0096] Reference Figures 1 to 3 The solid-state image sensor 10 includes a first metal mesh structure 111 and a second metal mesh structure 113. More specifically, the first metal mesh structure 111 is as follows: Figure 1 and Figure 2 As shown, it is disposed between the green filter layer 115G and the blue filter layer 115B, and as... Figure 1 and Figure 3 The second metal mesh structure 113 is positioned between the green filter layer 115G and the red filter layer 115R, as shown. Figures 1 to 3 The filter segments shown are located between the green filter segments 115GS, between the blue filter segments 115BS, and between the red filter segments 115RS, but this embodiment is not limited thereto.

[0097] like Figure 2 and Figure 3 As shown in the cross-sectional view of the solid-state image sensor 10, the first metal mesh structure 111 and the second metal mesh structure 113 are formed in a trapezoidal shape, but this disclosure is not limited thereto. In the embodiments of this disclosure, the bottom of the first metal mesh structure 111 has a first mesh width MW1, and the bottom of the second metal mesh structure 113 has a second mesh width MW2, and the second mesh width MW2 is smaller than the first mesh width MW1. In some embodiments, the ratio of the second mesh width MW2 to the first mesh width MW1 may be between about 0.25 and about 0.9 (i.e., MW2 / MW1 = 0.25 to 0.9), but this disclosure is not limited thereto.

[0098] In some embodiments, the materials of the first metal mesh structure 111 and the second metal mesh structure 113 may include tungsten (W), aluminum (Al), metal nitrides (e.g., titanium nitride (TiN)), other suitable materials, or combinations thereof, but the embodiments disclosed herein are not limited thereto. The first metal mesh structure 111 and the second metal mesh structure 113 can be formed by depositing a metal layer on the buffer layer 109, followed by patterning this metal layer using photolithography and etching processes, but the embodiments disclosed herein are not limited thereto.

[0099] In some embodiments, the second metal mesh structure 113 located between the green filter segments 115GS can be as follows: Figures 1 to 3 The second metal mesh structure 113G shown is located between the blue filter segments 115BS. The second metal mesh structure 113 can be as follows: Figure 1 and Figure 2 The structure shown is called the second metal mesh structure 113B, and the second metal mesh structure 113 located between the red filter segments 115RS can be as follows: Figure 1 and Figure 3 The structure shown is referred to as the second metal mesh structure 113R. Furthermore, the bottom of the second metal mesh structure 113G, located between the green filter segments 115GS, has a green mesh width MWG; the bottom of the second metal mesh structure 113B, located between the blue filter segments 115BS, has a blue mesh width MWB; and the bottom of the second metal mesh structure 113R, located between the red filter segments 115RS, has a red mesh width MWR.

[0100] In some embodiments, the second grid width MW2 is variable. For example, such as Figure 1 and Figure 2 As shown, the blue grid width MWB can be different from the green grid width MWG, such as... Figure 1 and Figure 3 As shown, the red grid width MWR may differ from the green grid width MWG, but this disclosure is not limited thereto. In some embodiments, the difference between the green grid width MWG and the blue grid width MWB, or the difference between the green grid width MWG and the red grid width MWR, may be between approximately 0 and 50 nm (i.e., MWB-MWG = 0 ± 50 nm or MWR-MWG = 0 ± 50 nm), but this disclosure is not limited thereto.

[0101] like Figure 2 and Figure 3 As shown, the solid-state image sensor 10 may include a partitioned mesh structure 121, which is disposed on the first metal mesh structure 111 and the second metal mesh structure 113. Figure 2and Figure 3 As shown, in the cross-section of the solid-state image sensor 10, the partition grid structure 121 is divided into multiple partition grid segments 121S.

[0102] In some embodiments, the material of the partition mesh structure 121 may comprise a transparent dielectric material having a low refractive index of about 1.0 to about 1.99. Furthermore, in embodiments of this disclosure, the refractive index of the partition mesh structure 121 is lower than the refractive index of the green filter layer 115G, the blue filter layer 115B, and the red filter layer 115R.

[0103] like Figure 2 As shown, the partition grid structure 121 (partition grid segment 121S) has a partition grid width 121W. In some embodiments, the partition grid width 121W may be greater than or equal to the first grid width MW1 at the bottom of the first metal grid structure 111. That is, the partition grid structure 121 may cover the first metal grid structure 111 and the second metal grid structure 113, but the embodiments disclosed herein are not limited thereto.

[0104] In the sensitivity measurements at different pixels of the same color (i.e., different color filter segments) in the solid-state image sensor 10 according to an embodiment of the present disclosure, Gr pixels (e.g., corresponding to...) Figure 3 The sensitivity difference in the green filter segment (115GS) is approximately 12.4% (normalized sensitivity), for Gb pixels (e.g., corresponding to...). Figure 2 The sensitivity difference in the green filter segment 115GS is approximately 9.9%. However, in conventional solid-state image sensors without metal mesh structures of varying mesh widths, the sensitivity difference for Gr pixels is approximately 16.1% (normalized sensitivity), and for Gb pixels it is approximately 13%. These results demonstrate that the solid-state image sensor 10 according to embodiments of this disclosure can achieve more consistent sensitivity for the same color at different pixels. Therefore, the channel separation problem can be improved, thereby improving the quality of the image signal from the photoelectric conversion elements of the solid-state image sensor.

[0105] like Figure 2 and Figure 3 As shown, in some embodiments, the solid-state image sensor 10 may include a transparent layer 117 disposed on a color filter layer (e.g., a green filter layer 115G, a blue filter layer 115B, or a red filter layer 115R) and a separating mesh structure 121. In some embodiments, the material of the transparent layer 117 may include glass, epoxy resin, silicone resin, polyurethane, other suitable materials, or combinations thereof, but this disclosure is not limited thereto.

[0106] like Figure 2 and Figure 3 As shown, in some embodiments, the solid-state image sensor 10 may include multiple light-focusing structures 119 disposed on a color filter layer (e.g., a green filter layer 115G, a blue filter layer 115B, or a red filter layer 115R) to converge incident light. In particular, the light-focusing structure 119 may be disposed on a transparent layer 117, but this is not a limitation of the embodiments disclosed herein. In some embodiments, the material of the light-focusing structure 119 may be the same as or similar to the material of the transparent layer 117, but this is not a limitation of the embodiments disclosed herein.

[0107] In some embodiments, the light-concentrating structure 119 may be a microlens structure, such as a semi-convex lens or a convex lens, but this disclosure is not limited thereto. In some other embodiments, the light-concentrating structure 119 may be a micro-pyramid structure (e.g., a cone, a square pyramid, etc.) or a micro-trapezoidal structure (e.g., a flat-topped cone, a flat-topped square pyramid, etc.). Alternatively, the light-concentrating structure 119 may be a gradient-index structure.

[0108] exist Figure 2 and Figure 3 In the illustrated embodiments, each focusing structure 119 corresponds to one of the green filter segments 115GS, one of the blue filter segments 115BS, or one of the red filter segments 115RS, but this disclosure is not limited thereto. In some other embodiments, each focusing structure 119 may correspond to at least two of the green filter segments 115GS, at least two of the blue filter segments 115BS, or at least two of the red filter segments 115RS.

[0109] Figure 4 It corresponds to Figure 2 Another cross-sectional view of the solid-state image sensor 10. Figure 5 It corresponds to Figure 3 Another cross-sectional view of the solid-state image sensor 10. For example, Figure 2 and Figure 3 This is a cross-sectional view corresponding to the central region of the solid-state image sensor 10, and Figure 4 and Figure 5 It is a cross-sectional view corresponding to the edge (or periphery) region (outside the central region) of the solid-state image sensor 10.

[0110] Reference Figure 4 and Figure 5In the edge region of the solid-state image sensor 10, the second metal mesh structure 113 is offset relative to the center line of the corresponding dividing mesh segment 121S. For example, the second metal mesh structure 113 (i.e., the second metal mesh structure 113G) between the green filter segments 115GS is as follows: Figure 4 and Figure 5 The second metal mesh structure 113 (i.e., the second metal mesh structure 113B) is shown to have an offset dG relative to the center line of the corresponding dividing grid segment 121S, and is located between the blue filter segments 115BS. Figure 4 The second metal mesh structure 113 (i.e., the second metal mesh structure 113R) is offset by a dB relative to the center line of the corresponding dividing grid segment 121S, while the second metal mesh structure 113 between the red filter segments 115RS is as follows: Figure 5 The center line of the corresponding dividing grid segment 121S is offset by a dR.

[0111] In some embodiments, the offset of the second metal mesh structure 113 relative to the center line of the corresponding dividing mesh segment 121S is variable. That is, in Figure 4 and Figure 5 The offsets dG, dB, and dR shown may be the same, but this disclosure is not limited thereto. In some embodiments, the difference between offset dG and offset dB or the difference between offset dG and offset dR may be between about 0 and 50 nm (i.e., dG-dB = 0 ± 50 nm or dG-dR = 0 ± 50 nm), but this disclosure is not limited thereto.

[0112] Furthermore, in some embodiments, the second metallic mesh structure 113 is offset towards the side away from the incident light L in the horizontal direction. For example, such as Figure 4 and Figure 5 As shown, the horizontal direction D can be parallel to the top surface of the green filter layer 115G, the blue filter layer 115B, and the red filter layer 115R. The incident light L comes from the left side, while the second metal mesh structure 113 (e.g., the second metal mesh structure 113G, the second metal mesh structure 113B, and the second metal mesh structure 113R) is offset to the right. However, the embodiments disclosed herein are not limited thereto.

[0113] In some embodiments, such as Figure 4 and Figure 5 As shown, the light-concentrating structure 119 also has an offset relative to the color filter layers (e.g., green filter layer 115G, blue filter layer 115B, red filter layer 115R) in the edge region of the solid-state image sensor 10, but this disclosure is not limited thereto.

[0114] In the foregoing embodiments, the partition mesh structure 121 completely covers the second metal mesh structure 113. That is, the second metal mesh structure 113 may be disposed inside the partition mesh structure 121, but this disclosure is not limited thereto.

[0115] Figure 6 This is a cross-sectional view showing a solid-state image sensor 12 according to another embodiment of the present disclosure. Figure 6 The solid-state image sensor 12 shown has the same characteristics as... Figure 4 The solid-state image sensor 10 shown has a similar structure. Furthermore, Figure 6 This is a cross-sectional view corresponding to the edge region of the solid-state image sensor 12.

[0116] Reference Figure 6 ,and Figure 4 The difference in the solid-state image sensor 10 shown is that, Figure 6 The color filter layer of the solid-state image sensor 12 shown may cover a portion of the second metal mesh structure 113. More specifically, as... Figure 6 As shown, the blue filter layer 115B (blue filter segment 115BS) can cover a portion of the second metal mesh structure 113B', while the green filter layer 115G (green filter segment 115GS) can cover a portion of the second metal mesh structure 113G'. That is, compared to... Figure 4 The solid-state image sensor 10 shown has an offset dB' that can be greater than offset dB and an offset dG' that can be greater than offset dG, such that a portion of the second metal mesh structure 113 can extend beyond the corresponding dividing mesh structure 121, but this disclosure is not limited thereto.

[0117] Figure 7 This is a cross-sectional view showing a solid-state image sensor 14 according to another embodiment of the present disclosure. Figure 8 It corresponds to Figure 7 Another cross-sectional view of the solid-state image sensor 14. For example, Figure 7 This is a cross-sectional view corresponding to the central region of the solid-state image sensor 14, and Figure 8 It is a cross-sectional view corresponding to the edge (or periphery) region of the solid-state image sensor 14 (which is outside the central region).

[0118] Reference Figure 7 and Figure 8 The photoelectric conversion element 103 can be arranged to correspond to a plurality of phase detection auto focus pixels (PDAF), a plurality of first regular pixels P1 surrounding the phase detection auto focus pixels (PDAF), and a plurality of second regular pixels P2 surrounding the first regular pixels P1.

[0119] In this embodiment, in the region corresponding to the phase detection autofocus pixel PDAF, each color filter segment (e.g., the green filter segment 115GS) may correspond to at least two photoelectric conversion elements 103; in the region corresponding to the first regular pixel P1 or the second regular pixel P2, each color filter segment (e.g., the green filter segment 115GS) may correspond to one photoelectric conversion element 103, but the embodiments of the present disclosure are not limited thereto.

[0120] In some embodiments, as Figure 7 shown, the first metal grid structure 111 may be correspondingly disposed in the region between the phase detection autofocus pixel PDAF and the first regular pixel P1, and the second metal grid structure 113 may be correspondingly disposed in the region between the first regular pixel P1 and the second regular pixel P2, but the embodiments of the present disclosure are not limited thereto.

[0121] Similarly, in this embodiment, the bottom of the first metal grid structure 111 has a first grid width MW1, the bottom of the second metal grid structure 113 has a second grid width MW2, and the second grid width MW2 is less than the first grid width MW1. In some embodiments, the ratio of the second grid width MW2 to the first grid width MW1 may be between about 0.25 and about 0.9 (i.e., MW2 / MW1 = 0.25 to 0.9), but the embodiments of the present disclosure are not limited thereto. In addition, in the edge region of the solid-state image sensor 14, the second metal grid structure 113 has an offset (e.g., offset dG) relative to the center line of the corresponding partition grid segment 121S.

[0122] Figure 9 is a cross-sectional view showing a solid-state image sensor 16 according to an embodiment of the present disclosure. Referring to Figure 9 , the solid-state image sensor 16 may have a structure similar to that of the solid-state image sensor 10 shown in Figure 3 . Different from the solid-state image sensor 10 shown in Figure 3 , in the solid-state image sensor 16 shown in Figure 9 , the first metal grid structure 111 may have a first grid height MH1, and the second metal grid structure 113 may have a second grid height MHR (or MHG). In this embodiment, the second grid height MHR (or MHG) may be lower than the first grid height MH1 (i.e., MHR < MH1 or MHG < MH1).

[0123] In addition, in some embodiments, the second grid height of the second metal grid structure 113 is variable. For example, as Figure 9 shown, the second grid height MHR may be higher than the second grid height MHG, but the embodiments of the present disclosure are not limited thereto.​​

[0124] In the foregoing embodiments, the first metal mesh structure 111 and the second metal mesh structure 113 are shown as trapezoids in a cross-sectional view of the solid-state image sensor, but the embodiments disclosed herein are not limited thereto.

[0125] Figure 10 This is a cross-sectional view showing a solid-state image sensor 18 according to an embodiment of the present disclosure. Figure 11 This is a cross-sectional view showing a solid-state image sensor 20 according to another embodiment of the present disclosure. (Refer to...) Figure 10 In the cross-sectional view of the solid-state image sensor 18, the first metal mesh structure 111' and the second metal mesh structure 113' form a triangle, but this embodiment is not limited thereto. (See also...) Figure 11 In the cross-sectional view of the solid-state image sensor 20, the first metal mesh structure 111” and the second metal mesh structure 113” are formed into a rectangle, but the embodiments disclosed herein are not limited thereto.

[0126] Figure 12 This is a cross-sectional view showing a solid-state image sensor 22 according to an embodiment of the present disclosure. (Refer to...) Figure 12 The solid-state image sensor 22 may have the same characteristics as... Figure 3 The solid-state image sensor 10 shown has a similar structure. (And...) Figure 3 The difference between the solid-state image sensor 10 and the solid-state image sensor 22 is that the thickness of the light-concentrating structures (119-1, 119-2) can be different. More specifically, as... Figure 12 As shown, the solid-state image sensor 22 may include multiple light-gathering structures 119-1 and 119-2 disposed on a first light-gathering structure 119-1 and multiple second light-gathering structures 119-2, which are disposed on a color filter layer (e.g., a green filter layer 115G, a blue filter layer 115B, or a red filter layer 115R). In this embodiment, the first light-gathering structure 119-1 may have a first thickness ML1, and the second light-gathering structure 119-2 may have a second thickness ML2, and the first thickness ML1 may be greater than the second thickness ML2, but this embodiment is not limited thereto.

[0127] In summary, compared to traditional mesh structures with a fixed metal mesh width, the solid-state image sensor of this disclosure includes a first metal mesh structure and a second metal mesh structure with different widths, which can improve channel separation and thereby improve the quality of the image signal from the photoelectric conversion element of the solid-state image sensor.

[0128] The components of several embodiments have been outlined above to enable those skilled in the art to better understand the views expressed in the embodiments of this disclosure. Those skilled in the art should understand that they can design or modify other processes and structures based on the embodiments of this disclosure to achieve the same purpose and / or advantages as the embodiments described herein. Those skilled in the art should also understand that such equivalent structures do not depart from the spirit and scope of this disclosure, and that they can make various changes, substitutions, and replacements without departing from the spirit and scope of this disclosure. Therefore, the scope of protection of this disclosure is determined by the appended claims. Furthermore, although this disclosure has been described above with reference to several preferred embodiments, it is not intended to limit the scope of this disclosure.

[0129] References to features, advantages, or similar language throughout this specification are not intended to imply that all features and advantages achievable using this disclosure should or may be implemented in any single embodiment of this disclosure. Rather, language relating to features and advantages is to be understood as meaning that a particular feature, advantage, or characteristic described in connection with an embodiment is included in at least one embodiment of this disclosure. Thus, the discussion of features and advantages, as well as similar language, throughout this specification may, but does not necessarily, represent the same embodiments.

[0130] Furthermore, in one or more embodiments, the features, advantages, and characteristics described in this disclosure may be combined in any suitable manner. Based on the description herein, those skilled in the art will recognize that this disclosure may be implemented without one or more specific features or advantages of a particular embodiment. In other instances, additional features and advantages may be identified in certain embodiments that may not be present in all embodiments of this disclosure.

Claims

1. A solid-state image sensor, comprising: Multiple photoelectric conversion elements; A first color filter layer is disposed above the plurality of photoelectric conversion elements and has a plurality of first color filter segments; A second color filter layer is disposed above the plurality of photoelectric conversion elements and adjacent to the first color filter layer, and has a plurality of second color filter segments; A first metal mesh structure is disposed between the first color filter layer and the second color filter layer; A second metal mesh structure is disposed between a plurality of first color filter segments and a plurality of second color filter segments; and A partitioned mesh structure is disposed on the first metal mesh structure and the second metal mesh structure. The first metal mesh structure has a first mesh width at its bottom, and the second metal mesh structure has a second mesh width at its bottom, which is smaller than the first mesh width. In a cross-section of the solid-state image sensor, the dividing mesh structure is divided into multiple dividing mesh segments. In an edge region of the solid-state image sensor, the second metal mesh structure is offset relative to the center line of each dividing mesh segment.

2. The solid-state image sensor of claim 1, wherein the plurality of first color filter segments include a plurality of green filter segments, and the plurality of second color filter segments include a plurality of blue / red filter segments, the bottom of the second metal mesh structure between the plurality of green filter segments has a green mesh width, the bottom of the second metal mesh structure between the plurality of blue / red filter segments has a blue / red mesh width, the blue / red mesh width is different from the green mesh width, and the difference between the green mesh width and the blue / red mesh width is between 0 nm and 50 nm.

3. The solid-state image sensor of claim 1, wherein in the cross-section of the solid-state image sensor, the dividing grid structure has a dividing grid width greater than or equal to the first grid width.

4. The solid-state image sensor of claim 1, wherein the plurality of first color filter segments include a plurality of green filter segments, and the plurality of second color filter segments include a plurality of blue / red filter segments.

5. The solid-state image sensor of claim 4, wherein in the edge region of the solid-state image sensor, a second metal mesh structure between the plurality of green filter segments has a first offset relative to the center line of each of the dividing mesh segments, and a second metal mesh structure between the plurality of blue / red filter segments has a second offset relative to the center line of each of the dividing mesh segments, the first offset being different from the second offset, and the difference between the first offset and the second offset being between 0 nm and 50 nm.

6. The solid-state image sensor of claim 1, wherein in a horizontal direction, the second metal mesh structure is offset toward the side away from the incident light.

7. The solid-state image sensor as described in claim 1, The first color filter layer or the second color filter layer covers a portion of the second metal mesh structure.

8. The solid-state image sensor of claim 1, wherein the plurality of photoelectric conversion elements are arranged to correspond to a plurality of phase detection autofocus pixels, a plurality of first normal pixels surrounding the plurality of phase detection autofocus pixels, and a plurality of second normal pixels surrounding the plurality of first normal pixels, the first metal mesh structure being disposed in the region between the plurality of phase detection autofocus pixels and the plurality of first normal pixels, and the second metal mesh structure being disposed in the region between the plurality of first normal pixels and the plurality of second normal pixels.

9. The solid-state image sensor of claim 1, wherein the first metal mesh structure has a first mesh height, the second metal mesh structure has a second mesh height, the second mesh height being lower than the first mesh height, and in a cross-sectional view of the solid-state image sensor, the first metal mesh structure and the second metal mesh structure are formed as a trapezoid, triangle, or rectangle, and the ratio of the second mesh width to the first mesh width is between 0.25 and 0.

9.

10. The solid-state image sensor of claim 1, further comprising: Multiple light-concentrating structures are disposed on the first color filter layer and the second color filter layer, wherein the multiple light-concentrating structures have different thicknesses.

Images