Solid-state image sensor
By employing a stacked structure of diffraction and absorption layers in the CMOS image sensor, the pixel design was optimized, the problem of reduced filtering efficiency of color filters was solved, and image sensing effects with high signal-to-noise ratio and high transmittance were achieved.
Patent Information
- Application Number
- CN202411283780.5
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Priority Date
- 2024-04-26
- Filing Date
- 2024-09-13
- Publication Date
- 2025-11-04
AI Technical Summary
In the process of reducing pixel size to increase resolution, existing CMOS image sensors reduce the filtering efficiency of color filters, resulting in a decrease in sensing contrast and color performance.
It employs a stacked structure of diffraction and absorption layers. The diffraction layer contains multiple diffraction elements, and the absorption layer contains multiple absorption elements. Pixels are defined by diffraction and absorption elements, and optical performance is optimized by adjusting the shape and arrangement of the elements.
This improves the signal-to-noise ratio (SNR) and light transmittance of the image sensor, while reducing the height of the color filter layer, thus enhancing sensing contrast and color performance.
Smart Images
Figure CN120897538A_ABST
Abstract
Description
Technical Field
[0001] This disclosure relates to an image sensor, and more particularly to a solid-state image sensor comprising a diffraction layer and an absorption layer stacked on top of each other to achieve high signal-to-noise ratio (SNR) performance and high transmittance. Background Technology
[0002] Solid-state image sensors (e.g., complementary metal-oxide-semiconductor (CMOS) image sensors) are widely used in various image-capturing devices, such as digital still cameras, digital camcorders, or the like. In the light-sensing section (e.g., a photoelectric conversion element) of a solid-state image sensor, a signal charge can be generated based on the amount of light received. Furthermore, the signal charge generated by the light-sensing section can be transmitted and amplified to obtain an image signal.
[0003] Recently, the trend in image sensors, represented by CMOS image sensors, has been to gradually reduce the pixel size in order to increase the number of pixels and thus provide high-resolution images. However, thinner color filters may lead to lower filtering efficiency, thereby reducing sensing contrast and color performance. Summary of the Invention
[0004] The purpose of this invention is to provide a solid-state image sensor to solve at least one of the above-mentioned problems.
[0005] According to embodiments of this disclosure, a solid-state image sensor includes a diffraction layer and an absorption layer stacked on top of each other to achieve high signal-to-noise ratio (SNR) performance and high transmittance. Furthermore, in some embodiments, the stacked diffraction layer and absorption layer may be applied to the color filter layer of the solid-state image sensor, thereby reducing the height of the color filter layer.
[0006] Embodiments of this disclosure provide a solid-state image sensor. The solid-state image sensor includes a diffraction layer and an absorption layer. The diffraction layer includes a plurality of diffraction elements having a plurality of top center gaps, while the absorption layer is disposed below the diffraction layer and includes a plurality of absorption elements having a plurality of bottom center gaps. A plurality of pixels of the solid-state image sensor are defined by the diffraction elements and the absorption elements. The pixels are arranged in an array. Each top center gap corresponds to a bottom center gap and a pixel.
[0007] In some embodiments, in a top view, each diffraction element or each absorption element is formed as a split cross, a hollow cross, a split rectangular grid, or a hollow rectangular block.
[0008] In some embodiments, in a top view, each diffraction element has two top horizontal portions arranged along a first direction and two top vertical portions arranged along a second direction perpendicular to the first direction, each top center gap being defined by the top horizontal portions and the top vertical portions, and each top vertical portion being formed as a rectangle having a first width in the first direction and a second width in the second direction.
[0009] In some embodiments, the first width is less than the sum of the width of each top center gap and the second width.
[0010] In some embodiments, the width of each top center gap is greater than a first width, the first width is less than a second width, the top period is defined by the distance between the centers of two adjacent top center gaps, and the distance between the centers of the top horizontal portions is 0.60 to 0.86 top periods.
[0011] In some embodiments, the width of each top center gap is greater than a first width, the first width is greater than a second width, the top period is defined by the distance between the centers of two adjacent top center gaps, and the distance between the centers of the top horizontal portions is 0.63 to 0.77 top periods.
[0012] In some embodiments, the width of each top center gap is less than a first width, the first width is less than a second width, the top period is defined by the distance between the centers of two adjacent top center gaps, and the distance between the centers of the top horizontal portions is 0.52 to 0.91 top periods.
[0013] In some embodiments, the width of each top center gap is less than a first width, the first width is greater than a second width, the top period is defined by the distance between the centers of two adjacent top center gaps, and the distance between the centers of the top horizontal portions is 0.61 to 0.69 top periods.
[0014] In some embodiments, in a top view, each absorbing element has two bottom horizontal portions arranged along a first direction and two bottom vertical portions arranged along a second direction perpendicular to the first direction, each bottom center gap being defined by the bottom horizontal portions and the bottom vertical portions, and each bottom vertical portion being formed as a rectangle having a third width in the first direction and a fourth width in the second direction.
[0015] In some embodiments, the third width is less than the sum of the width of each bottom center gap and the fourth width.
[0016] In some embodiments, the width of each bottom center gap is greater than the third width.
[0017] In some embodiments, the third width is less than the fourth width, the bottom period is defined by the distance between the centers of two adjacent bottom center gaps, and the distance between the centers of the bottom horizontal portions is 0.60 to 0.71 bottom periods.
[0018] In some embodiments, the third width is greater than the fourth width, the bottom period is defined by the distance between the centers of two adjacent bottom center gaps, and the distance between the centers of the bottom horizontal portions is 0.42 to 0.77 bottom periods.
[0019] In some embodiments, the width of each bottom center gap is less than the third width.
[0020] In some embodiments, the third width is less than the fourth width, the bottom period is defined by the distance between the centers of two adjacent bottom center gaps, and the distance between the centers of the bottom horizontal portions is 0.60 to 0.95 bottom periods.
[0021] In some embodiments, the third width is greater than the fourth width, the bottom period is defined by the distance between the centers of two adjacent bottom center gaps, and the distance between the centers of the bottom horizontal portions is 0.57 to 0.69 bottom periods.
[0022] In some embodiments, the solid-state image sensor further includes an intermediate layer disposed between the diffraction layer and the absorption layer, and each pixel corresponds to a portion of the intermediate layer.
[0023] In some embodiments, the intermediate layer is a color filter layer, and the absorption layer is embedded at the bottom of the intermediate layer.
[0024] In some embodiments, the solid-state image sensor further includes a light-focusing structure disposed above the diffraction layer.
[0025] In some embodiments, the diffraction element comprises tantalum pentoxide, and the absorption element comprises titanium dioxide, titanium, gold, silver, silicon, silicon nitride, graphene, copper, bismuth, palladium, platinum, aluminum, carbon, titanium nitride, aluminum aluminum nitride, amorphous silicon, or a combination thereof. 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, according to industry standard practice, the various feature components are not drawn to scale. In fact, the dimensions of the various feature components may be enlarged or reduced to clearly demonstrate the technical features of the embodiments of this disclosure.
[0027] FIG. 1 This is a partial cross-sectional view of a solid-state image sensor according to some embodiments of the present disclosure.
[0028] FIG. 2AThis is a top view of a diffraction element according to some embodiments of the present disclosure.
[0029] FIG. 2B It is a top view showing one arrangement of multiple diffraction elements.
[0030] FIG. 2C This is a top view showing another arrangement of multiple diffraction elements.
[0031] FIG. 3A This is a top view of a diffraction element according to some other embodiments of the present disclosure.
[0032] FIG. 3B It is a top view showing one arrangement of multiple diffraction elements.
[0033] FIG. 3C This is a top view showing another arrangement of multiple diffraction elements.
[0034] FIG. 4A This is a top view of a diffraction element according to some other embodiments of the present disclosure.
[0035] FIG. 4B A top view showing one arrangement of multiple diffraction elements.
[0036] FIG. 4C A top view showing another arrangement of multiple diffractive elements.
[0037] FIG. 5A This is a top view of a diffraction element according to some other embodiments of the present disclosure.
[0038] FIG. 5B A top view showing one arrangement of multiple diffraction elements.
[0039] FIG. 5C A top view showing another arrangement of multiple diffractive elements.
[0040] FIG. 6A This is a top view showing an absorption element according to some embodiments of the present disclosure.
[0041] FIG. 6B A top view showing one arrangement of multiple absorbing elements.
[0042] FIG. 6C A top view showing another arrangement of multiple absorbing elements.
[0043] FIG. 7A This is a top view of the absorption element according to some other embodiments of the present disclosure.
[0044] FIG. 7B A top view showing one arrangement of multiple absorbing elements.
[0045] FIG. 7C A top view showing another arrangement of multiple absorbing elements.
[0046] FIG. 8A This is a top view of the absorption element according to some other embodiments of the present disclosure.
[0047] FIG. 8B A top view showing one arrangement of multiple absorbing elements.
[0048] FIG. 8C A top view showing another arrangement of multiple absorbing elements.
[0049] FIG. 9A This is a top view of the absorption element according to some other embodiments of the present disclosure.
[0050] FIG. 9B A top view showing one arrangement of multiple absorbing elements.
[0051] FIG. 9C A top view showing another arrangement of multiple absorbing elements.
[0052] FIG. 10 This is a partial cross-sectional view of a solid-state image sensor according to some other embodiments of the present disclosure.
[0053] FIG. 11 The transmission spectrum of a solid-state image sensor according to comparative examples and embodiments of the present disclosure is shown when the intermediate layer is a red filter layer with a thickness of about 300 nanometers.
[0054] FIG. 12 The transmission spectrum of a solid-state image sensor according to comparative examples and embodiments of the present disclosure is shown when the intermediate layer is a green filter layer with a thickness of about 300 nanometers.
[0055] FIG. 13 The transmission spectrum of a solid-state image sensor according to comparative examples and embodiments of the present disclosure is shown when the intermediate layer is a blue filter layer with a thickness of about 300 nanometers.
[0056] The attached figures are labeled as follows:
[0057] 100: Solid-state image sensor
[0058] 10: Diffraction layer
[0059] 10G: Top center gap
[0060] 10P: Diffraction element
[0061] 11: Top horizontal section
[0062] 13: Top vertical section
[0063] 20: Absorption layer
[0064] 20G: Bottom center gap
[0065] 20P: Absorption element
[0066] 21: Bottom horizontal section
[0067] 23: Bottom vertical section
[0068] 30: Intermediate layer
[0069] 41: Semiconductor substrate
[0070] 43: Space Layer
[0071] 45: Concentrating structure
[0072] A-A': line
[0073] P: pixel
[0074] BD, TD: Distance
[0075] BG, BL, BW, TG, TL, TW: Width
[0076] BP: Bottom cycle
[0077] T: Thickness
[0078] TP: Top Cycle
[0079] X, Y, Z: Coordinate axes Detailed Implementation
[0080] The following disclosure provides many different embodiments or examples to implement various features of the invention. Specific examples of the various components and their arrangements described below are provided to simplify this disclosure. Of course, these are merely examples and are not intended to be limiting. For example, if it is stated that a first feature is formed on or above a second feature, it may include embodiments where the first and second feature are in direct contact, or embodiments where other feature is formed between the first and second feature, so that the first and second feature may not be in direct contact.
[0081] It should be understood that other operational steps may be performed before, between, or after the method, and in other embodiments of the method, some operational steps may be replaced or omitted.
[0082] Furthermore, spatially related terms such as “below,” “under,” “down,” “above,” “above,” and similar terms may be used herein to facilitate the description of the relationship between one element or feature and other elements or features in the accompanying drawings. These spatially related terms encompass different orientations of the device in use or operation, as well as the orientations described in the accompanying drawings. The device may be turned to different orientations (rotated 90 degrees or other orientations), and the spatially related adjectives used herein will be interpreted in accordance with the orientation after the turn.
[0083] In this disclosure, the terms "about," "approximately," and "substantially" generally mean within 20%, 10%, 5%, 3%, 2%, 1%, or even 0.5% of a given value. The given values in this disclosure are approximate values. That is, even without a specific description of "about," "approximately," or "substantially," a given value may still contain the meaning of "about," "approximately," or "substantially."
[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 should be understood that these terms, such as those defined in commonly used dictionaries, should be interpreted in a meaning consistent with the context of the relevant art and will not be interpreted in an idealized or overly formal manner, unless specifically defined in the embodiments of this disclosure.
[0085] The same reference numerals and / or designations may be used repeatedly in the following embodiments. These repetitions are for simplicity and clarity purposes and are not intended to limit any specific relationship between the various embodiments and / or structures discussed.
[0086] FIG. 1 This is a partial cross-sectional view of a solid-state image sensor 100 according to some embodiments of the present disclosure. It should be noted that, for the sake of brevity, FIG. 1 Some components of the solid-state image sensor 100 have been omitted.
[0087] Reference FIG. 1 In some embodiments, the solid-state image sensor 100 includes a diffraction layer 10 and an absorption layer 20, with the absorption layer 20 disposed below the diffraction layer 10. In some embodiments, the diffraction layer 10 includes a plurality of diffraction elements 10P, each diffraction element 10P having a plurality of top center gaps 10G (see [link to documentation]). FIG. 2A to FIG. 5A The absorber layer 20 includes a plurality of absorber elements 20P, each absorber element 20P having a plurality of bottom center gaps 20G (see [link]). FIG. 6A to FIG. 9AIn some embodiments, a plurality of pixels P of the solid-state image sensor 100 are defined by a diffraction element 10P and an absorption element 20P, and the pixels P are arranged in an array. FIG. 1 (and FIG. 2B , FIG. 2C , FIG. 3B , FIG. 3C , FIG. 4B , FIG. 4C , FIG. 5B , FIG. 5C , FIG. 6B , FIG. 6C , FIG. 7B , FIG. 7C , FIG. 8B , FIG. 8C , FIG. 9B and FIG. 9C As shown in the figure, each top center gap 10G corresponds to a bottom center gap 20G and a pixel P.
[0088] FIG. 2A This is a top view of the diffraction element 10P according to some embodiments of the present disclosure. FIG. 2B This is a top view showing one arrangement of multiple diffraction elements 10P. FIG. 2C This is a top view showing another arrangement of the multiple diffraction elements 10P. For example, FIG. 2B The display shows four diffraction elements 10P, which correspond to four pixels P arranged in a 2×2 array. FIG. 2C The display shows six diffraction elements 10P, which correspond to six pixels P arranged in a 2×3 (or 3×2) array, while FIG. 1 It can be along FIG. 2C The image shows a partial cross-sectional view of the solid-state image sensor 100 cut by line A-A', but the embodiments disclosed herein are not limited thereto.
[0089] Reference FIG. 2A In this embodiment, the diffraction element 10P is formed as a split cross. In some embodiments, the diffraction element 10P comprises tantalum pentoxide (Ta₂O₅), which may have a high refractive index, but this disclosure is not limited thereto. More specifically, in this embodiment, the diffraction element 10P has two top horizontal portions 11 arranged along the X direction and two top vertical portions 13 arranged along the Y direction. The Y direction is perpendicular to the X direction. FIG. 2A As shown, the top center gap 10G is defined by the top horizontal portion 11 and the top vertical portion 13. For example, in FIG. 2A In the top view shown, the top horizontal portion 11 is located to the left and right of the top center gap 10G, while the top vertical portion 13 is located above and below the top center gap 10G.
[0090] likeFIG. 2A As shown, in some embodiments, each top vertical portion 13 is formed as a rectangle having a width TL in the X direction and a width TW in the Y direction. In this embodiment, the top horizontal portion 11 has the same shape and size as the top vertical portion 13, but with a different orientation. More specifically, each top horizontal portion 11 is formed as a rectangle having a width TL in the Y direction and a width TW in the X direction, but this disclosure is not limited thereto.
[0091] In some embodiments, the width TL is less than the sum of the width TG and the width TW of the top center gap 10G. Here, the sum of the width TG and the width TW of the top center gap 10G is equal to the distance between the centers of the top horizontal portions 11 or the distance between the centers of the top vertical portions 13. Furthermore, in this embodiment, the width TG of the top center gap 10G is greater than the width TL, and the width TL is less than the width TW.
[0092] like FIG. 2B and FIG. 2C As shown, in this embodiment, the top period TP is defined by the distance between the centers of two adjacent top center gaps 10G, while the distance TD between the centers of the top horizontal portions 11 (i.e., the sum of the width TG and width TW of the top center gaps 10G) is approximately 0.60 to approximately 0.86 top periods TP. Similarly, in this embodiment, the distance TD between the centers of the top vertical portions 13 (i.e., the sum of the width TG and width TW of the top center gaps 10G) is approximately 0.60 to approximately 0.86 top periods TP.
[0093] exist FIG. 2B In the above, the width TG of the top center gap 10G is about 142 nanometers (nm), the width TL is about 125 nanometers, the width TW is about 203 nanometers, and the distance TD between the centers of the top horizontal portions 11 (or between the centers of the top vertical portions 13) is about 345 nanometers, but the embodiments disclosed herein are not limited thereto.
[0094] exist FIG. 2C In the above, the width TG of the top center gap 10G is about 75 nanometers, the width TL is about 60 nanometers, the width TW is about 130 nanometers, and the distance TD between the centers of the top horizontal portions 11 (or between the centers of the top vertical portions 13) is about 240 nanometers, but the embodiments disclosed herein are not limited thereto.
[0095] FIG. 3A This is a top view of the diffraction element 10P according to some other embodiments of the present disclosure. FIG. 3B This is a top view showing one arrangement of multiple diffraction elements 10P. FIG. 3CThis is a top view showing another arrangement of the multiple diffraction elements 10P. For example, FIG. 3B The display shows four diffraction elements 10P, which correspond to four pixels P arranged in a 2×2 array, while FIG. 3C The present disclosure shows six diffraction elements 10P, which correspond to six pixels P arranged in a 2×3 (or 3×2) array, but the embodiments disclosed are not limited thereto.
[0096] Reference FIG. 3A In this embodiment, the diffraction element 10P is formed as a hollow cross. FIG. 3A As shown, in some embodiments, each top vertical portion 13 is formed as a rectangle having a width TL in the X direction and a width TW in the Y direction. In this embodiment, the top horizontal portion 11 has the same shape and size as the vertical portion 13, but with a different orientation. More specifically, each top horizontal portion 11 is formed as a rectangle having a width TL in the Y direction and a width TW in the X direction, but this disclosure is not limited thereto.
[0097] In some embodiments, the width TL is less than the sum of the width TG and the width TW of the top center gap 10G. Here, the sum of the width TG and the width TW of the top center gap 10G is equal to the distance between the centers of the top horizontal portions 11 or the distance between the centers of the top vertical portions 13. Furthermore, in this embodiment, the width TG of the top center gap 10G is less than the width TL, and the width TL is less than the width TW. In other words, a portion of the top horizontal portion 11 may overlap with a portion of the top vertical portion 13.
[0098] like FIG. 3B and FIG. 3C As shown, in this embodiment, the top period TP is defined by the distance between the centers of two adjacent top center gaps 10G, and the distance TD between the centers of the top horizontal portions 11 (i.e., the sum of the width TG and width TW of the top center gaps 10G) is approximately 0.52 to approximately 0.91 top periods TP. Similarly, in this embodiment, the distance TD between the centers of the top vertical portions 13 (i.e., the sum of the width TG and width TW of the top center gaps 10G) is approximately 0.52 to approximately 0.91 top periods TP.
[0099] exist FIG. 3B In the above, the width TG of the top center gap 10G is about 75 nanometers, the width TL is about 175 nanometers, the width TW is about 284 nanometers, and the distance TD between the centers of the top horizontal portions 11 (or between the centers of the top vertical portions 13) is about 361 nanometers, but the embodiments disclosed herein are not limited thereto.
[0100] exist FIG. 3CIn the above, the width TG of the top center gap 10G is about 75 nanometers, the width TL is about 80 nanometers, the width TW is about 130 nanometers, and the distance TD between the centers of the top horizontal portions 11 (or between the centers of the top vertical portions 13) is about 210 nanometers, but the embodiments disclosed herein are not limited thereto.
[0101] FIG. 4A This is a top view of the diffraction element 10P according to some other embodiments of the present disclosure. FIG. 4B A top view showing one arrangement of multiple diffraction elements 10P. FIG. 4C A top view showing another arrangement of multiple diffraction elements 10P. For example, FIG. 4B The display shows four diffraction elements 10P, which correspond to four pixels P arranged in a 2×2 array, while FIG. 4C The present disclosure shows six diffraction elements 10P, which correspond to six pixels P arranged in a 2×3 (or 3×2) array, but the embodiments disclosed are not limited thereto.
[0102] Reference FIG. 4A In this embodiment, the diffraction element 10P is formed as a split rectangular grid. For example... FIG. 4A As shown, in some embodiments, each top vertical portion 13 is formed as a rectangle having a width TL in the X direction and a width TW in the Y direction. In this embodiment, the top horizontal portion 11 has the same shape and size as the vertical portion 13, but with a different orientation. More specifically, each top horizontal portion 11 is formed as a rectangle having a width TL in the Y direction and a width TW in the X direction, but this disclosure is not limited thereto.
[0103] In some embodiments, the width TL is less than the sum of the width TG and the width TW of the top center gap 10G. Here, the sum of the width TG and the width TW of the top center gap 10G is equal to the distance between the centers of the top horizontal portions 11 or the distance between the centers of the top vertical portions 13. Furthermore, in this embodiment, the width TG of the top center gap 10G is greater than the width TL, and the width TL is greater than the width TW.
[0104] like FIG. 4B and FIG. 4CAs shown, in this embodiment, the top period TP is defined by the distance between the centers of two adjacent top center gaps 10G, and the distance TD between the centers of the top horizontal portions 11 (i.e., the sum of the width TG and width TW of the top center gaps 10G) is approximately 0.63 to approximately 0.77 top periods TP. Similarly, in this embodiment, the distance TD between the centers of the top vertical portions 13 (i.e., the sum of the width TG and width TW of the top center gaps 10G) is approximately 0.63 to approximately 0.77 top periods TP.
[0105] exist FIG. 4B In the above, the width TG of the top center gap 10G is about 200 nanometers, the width TL is about 180 nanometers, the width TW is about 110 nanometers, and the distance TD between the centers of the top horizontal portions 11 (or between the centers of the top vertical portions 13) is about 310 nanometers, but the embodiments disclosed herein are not limited thereto.
[0106] exist FIG. 4C In the above, the width TG of the top center gap 10G is about 175 nanometers, the width TL is about 155 nanometers, the width TW is about 95 nanometers, and the distance TD between the centers of the top horizontal portions 11 (or between the centers of the top vertical portions 13) is about 250 nanometers, but the embodiments disclosed herein are not limited thereto.
[0107] FIG. 5A This is a top view of the diffraction element 10P according to some other embodiments of the present disclosure. FIG. 5B A top view showing one arrangement of multiple diffraction elements 10P. FIG. 5C A top view showing another arrangement of multiple diffraction elements 10P. For example, FIG. 5B The display shows four diffraction elements 10P, which correspond to four pixels P arranged in a 2×2 array, while FIG. 5C The present disclosure shows six diffraction elements 10P, which correspond to six pixels P arranged in a 2×3 (or 3×2) array, but the embodiments disclosed are not limited thereto.
[0108] Reference FIG. 5A In this embodiment, the diffraction element 10P is formed as a hollow rectangular block. For example... FIG. 5A As shown, in some embodiments, each top vertical portion 13 is formed as a rectangle having a width TL in the X direction and a width TW in the Y direction. In this embodiment, the top horizontal portion 11 has the same shape and size as the vertical portion 13, but with a different orientation. More specifically, each top horizontal portion 11 is formed as a rectangle having a width TL in the Y direction and a width TW in the X direction, but this disclosure is not limited thereto.
[0109] In some embodiments, the width TL is less than the sum of the width TG and the width TW of the top center gap 10G. Here, the sum of the width TG and the width TW of the top center gap 10G is equal to the distance between the centers of the top horizontal portions 11 or the distance between the centers of the top vertical portions 13. Furthermore, in this embodiment, the width TG of the top center gap 10G is less than the width TL, and the width TL is greater than the width TW. In other words, a portion of the top horizontal portion 11 may overlap with a portion of the top vertical portion 13.
[0110] like FIG. 5B and FIG. 5C As shown, in this embodiment, the top period TP is defined by the distance between the centers of two adjacent top center gaps 10G, and the distance TD between the centers of the top horizontal portions 11 (i.e., the sum of the width TG and width TW of the top center gaps 10G) is approximately 0.61 to approximately 0.69 top periods TP. Similarly, in this embodiment, the distance TD between the centers of the top vertical portions 13 (i.e., the sum of the width TG and width TW of the top center gaps 10G) is approximately 0.61 to approximately 0.69 top periods TP.
[0111] exist FIG. 5B In the above, the width TG of the top center gap 10G is about 140 nanometers, the width TL is about 220 nanometers, the width TW is about 135 nanometers, and the distance TD between the centers of the top horizontal portion 11 (or between the centers of the top vertical portion 13) is about 280 nanometers, but the embodiments disclosed herein are not limited thereto.
[0112] exist FIG. 5C In the above, the width TG of the top center gap 10G is about 140 nanometers, the width TL is about 170 nanometers, the width TW is about 105 nanometers, and the distance TD between the centers of the top horizontal portions 11 (or between the centers of the top vertical portions 13) is about 245 nanometers, but the embodiments disclosed herein are not limited thereto.
[0113] FIG. 6A This is a top view of the absorption element 20P according to some embodiments of the present disclosure. FIG. 6B A top view showing one arrangement of multiple absorption elements 20P. FIG. 6C A top view showing another arrangement of multiple absorption elements 20P. For example, FIG. 6B The display shows four absorption elements 20P, which correspond to four pixels P arranged in a 2×2 array. FIG. 6C The display shows six absorption elements 20P, which correspond to six pixels P arranged in a 2×3 (or 3×2) array, while FIG. 1 It can be along FIG. 6CThe image shows a partial cross-sectional view of the solid-state image sensor 100 cut by line A-A', but the embodiments disclosed herein are not limited thereto.
[0114] Reference FIG. 6A In this embodiment, the absorber element 20P is formed as a split cross. In some embodiments, the absorber element 20P comprises titanium dioxide, titanium, gold, silver, silicon, silicon nitride, graphene, copper, bismuth, palladium, platinum, aluminum, carbon, titanium nitride, aluminum aluminum nitride, amorphous silicon, or combinations thereof, but this disclosure is not limited thereto. More specifically, in this embodiment, the absorber element 20P has two bottom horizontal portions 21 arranged along the X direction and two bottom vertical portions 23 arranged along the Y direction. The Y direction is perpendicular to the X direction. FIG. 6A As shown, the bottom center gap 20G is defined by the bottom horizontal portion 21 and the bottom vertical portion 23. For example, in FIG. 6A In the top view shown, the bottom horizontal portion 21 is located to the left and right of the bottom center gap 20G, while the bottom vertical portion 23 is located above and below the bottom center gap 20G.
[0115] like FIG. 6A As shown, in some embodiments, each bottom vertical portion 23 is formed as a rectangle having a width BL in the X direction and a width BW in the Y direction. In this embodiment, the bottom horizontal portion 21 has the same shape and size as the vertical portion 23, but with a different orientation. More specifically, each bottom horizontal portion 21 is formed as a rectangle having a width BL in the Y direction and a width BW in the X direction, but this disclosure is not limited to this embodiment.
[0116] In some embodiments, the width BL is less than the sum of the widths BG and BW of the bottom center gap 20G. Here, the sum of the widths BG and BW of the bottom center gap 20G is equal to the distance between the centers of the bottom horizontal portions 21 or the distance between the centers of the bottom vertical portions 23. Furthermore, in this embodiment, the width BG of the bottom center gap 20G is greater than the width BL, and the width BL is less than the width BW.
[0117] like FIG. 6B and FIG. 6C As shown, in this embodiment, the bottom period BP is defined by the distance between the centers of two adjacent bottom center gaps 20G, and the distance BD between the centers of the bottom horizontal portions 21 (i.e., the sum of the widths BG and BW of the bottom center gaps 20G) is approximately 0.60 to approximately 0.71 bottom periods BP. Similarly, in this embodiment, the distance BD between the centers of the bottom vertical portions 23 (i.e., the sum of the widths BG and BW of the bottom center gaps 20G) is approximately 0.60 to approximately 0.71 bottom periods BP.
[0118] existFIG. 6B In the embodiment, the width BG of the bottom center gap 20G is about 140 nanometers, the width BL is about 120 nanometers, the width BW is about 145 nanometers, and the distance BD between the centers of the bottom horizontal portions 21 (or between the centers of the bottom vertical portions 23) is about 285 nanometers, but the embodiments disclosed herein are not limited thereto.
[0119] exist FIG. 6C In the embodiment, the width BG of the bottom center gap 20G is about 100 nanometers, the width BL is about 100 nanometers, the width BW is about 145 nanometers, and the distance BD between the centers of the bottom horizontal portions 21 (or between the centers of the bottom vertical portions 23) is about 240 nanometers, but the embodiments disclosed herein are not limited thereto.
[0120] FIG. 7A This is a top view of the absorption element 20P according to some other embodiments of the present disclosure. FIG. 7B A top view showing one arrangement of multiple absorption elements 20P. FIG. 7C A top view showing another arrangement of multiple absorption elements 20P. For example, FIG. 7B The display shows four absorption elements 20P, which correspond to four pixels P arranged in a 2×2 array, while FIG. 7C The present disclosure shows six absorption elements 20P, which correspond to six pixels P arranged in a 2×3 (or 3×2) array, but is not limited thereto.
[0121] Reference FIG. 7A In this embodiment, the absorption element 20P is formed as a hollow cross. For example... FIG. 7A As shown, in some embodiments, each bottom vertical portion 23 is formed as a rectangle having a width BL in the X direction and a width BW in the Y direction. In this embodiment, the bottom horizontal portion 21 has the same shape and size as the vertical portion 23, but with a different orientation. More specifically, each bottom horizontal portion 21 is formed as a rectangle having a width BL in the Y direction and a width BW in the X direction, but this disclosure is not limited to this embodiment.
[0122] In some embodiments, the width BL is less than the sum of the widths BG and BW of the bottom center gap 20G. Here, the sum of the widths BG and BW of the bottom center gap 20G is equal to the distance between the centers of the bottom horizontal portions 21 or the distance between the centers of the bottom vertical portions 23. Furthermore, in this embodiment, the width BG of the bottom center gap 20G is less than the width BL, and the width BL is less than the width BW. In other words, a portion of the bottom horizontal portion 21 may overlap with a portion of the bottom vertical portion 23.
[0123] like FIG. 7B and FIG. 7CAs shown, in this embodiment, the bottom period BP is defined by the distance between the centers of two adjacent bottom center gaps 20G, and the distance BD between the centers of the bottom horizontal portions 21 (i.e., the sum of the widths BG and BW of the bottom center gaps 20G) is approximately 0.60 to approximately 0.95 bottom periods BP. Similarly, in this embodiment, the distance BD between the centers of the bottom vertical portions 23 (i.e., the sum of the widths BG and BW of the bottom center gaps 20G) is approximately 0.60 to approximately 0.95 bottom periods BP.
[0124] exist FIG. 7B In the embodiment, the width BG of the bottom center gap 20G is about 140 nanometers, the width BL is about 155 nanometers, the width BW is about 240 nanometers, and the distance BD between the centers of the bottom horizontal portions 21 (or between the centers of the bottom vertical portions 23) is about 380 nanometers, but the embodiments disclosed herein are not limited thereto.
[0125] exist FIG. 7C In the embodiment, the width BG of the bottom center gap 20G is about 100 nanometers, the width BL is about 100 nanometers, the width BW is about 143 nanometers, and the distance BD between the centers of the bottom horizontal portions 21 (or between the centers of the bottom vertical portions 23) is about 240 nanometers, but the embodiments disclosed herein are not limited thereto.
[0126] FIG. 8A This is a top view of the absorption element 20P according to some other embodiments of the present disclosure. FIG. 8B A top view showing one arrangement of multiple absorption elements 20P. FIG. 8C A top view showing another arrangement of multiple absorption elements 20P. For example, FIG. 8B The display shows four absorption elements 20P, which correspond to four pixels P arranged in a 2×2 array, while FIG. 8C The present disclosure shows six absorption elements 20P, which correspond to six pixels P arranged in a 2×3 (or 3×2) array, but is not limited thereto.
[0127] Reference FIG. 8A In this embodiment, the absorbing element 20P is formed as a split rectangular grid. For example... FIG. 8A As shown, in some embodiments, each bottom vertical portion 23 is formed as a rectangle having a width BL in the X direction and a width BW in the Y direction. In this embodiment, the bottom horizontal portion 21 has the same shape and size as the vertical portion 23, but with a different orientation. More specifically, each bottom horizontal portion 21 is formed as a rectangle having a width BL in the Y direction and a width BW in the X direction, but this disclosure is not limited to this embodiment.
[0128] In some embodiments, the width BL is less than the sum of the widths BG and BW of the bottom center gap 20G. Here, the sum of the widths BG and BW of the bottom center gap 20G is equal to the distance between the centers of the bottom horizontal portions 21 or the distance between the centers of the bottom vertical portions 23. Furthermore, in this embodiment, the width BG of the bottom center gap 20G is greater than the width BL, and the width BL is greater than the width BW.
[0129] like FIG. 8B and FIG. 8C As shown, in this embodiment, the bottom period BP is defined by the distance between the centers of two adjacent bottom center gaps 20G, and the distance BD between the centers of the bottom horizontal portions 21 (i.e., the sum of the widths BG and BW of the bottom center gaps 20G) is approximately 0.42 to approximately 0.77 bottom periods BP. Similarly, in this embodiment, the distance BD between the centers of the bottom vertical portions 23 (i.e., the sum of the widths BG and BW of the bottom center gaps 20G) is approximately 0.42 to approximately 0.77 bottom periods BP.
[0130] exist FIG. 8B In the embodiment, the width BG of the bottom center gap 20G is about 200 nanometers, the width BL is about 180 nanometers, the width BW is about 110 nanometers, and the distance BD between the centers of the bottom horizontal portions 21 (or between the centers of the bottom vertical portions 23) is about 310 nanometers, but the embodiments disclosed herein are not limited thereto.
[0131] exist FIG. 8C In the embodiment, the width BG of the bottom center gap 20G is about 110 nanometers, the width BL is about 110 nanometers, the width BW is about 60 nanometers, and the distance BD between the centers of the bottom horizontal portions 21 (or between the centers of the bottom vertical portions 23) is about 170 nanometers, but the embodiments disclosed herein are not limited thereto.
[0132] FIG. 9A This is a top view of the absorption element 20P according to some other embodiments of the present disclosure. FIG. 9B A top view showing one arrangement of multiple absorption elements 20P. FIG. 9C A top view showing another arrangement of multiple absorption elements 20P. For example, FIG. 9B The display shows four absorption elements 20P, which correspond to four pixels P arranged in a 2×2 array, while FIG. 9C The present disclosure shows six absorption elements 20P, which correspond to six pixels P arranged in a 2×3 (or 3×2) array, but is not limited thereto.
[0133] Reference FIG. 9A In this embodiment, the absorption element 20P is formed as a hollow rectangular block. For example... FIG. 9AAs shown, in some embodiments, each bottom vertical portion 23 is formed as a rectangle having a width BL in the X direction and a width BW in the Y direction. In this embodiment, the bottom horizontal portion 21 has the same shape and size as the vertical portion 23, but with a different orientation. More specifically, each bottom horizontal portion 21 is formed as a rectangle having a width BL in the Y direction and a width BW in the X direction, but this disclosure is not limited to this embodiment.
[0134] In some embodiments, the width BL is less than the sum of the widths BG and BW of the bottom center gap 20G. Here, the sum of the widths BG and BW of the bottom center gap 20G is equal to the distance between the centers of the bottom horizontal portions 21 or the distance between the centers of the bottom vertical portions 23. Furthermore, in this embodiment, the width BG of the bottom center gap 20G is less than the width BL, and the width BL is greater than the width BW. In other words, a portion of the bottom horizontal portion 21 may overlap with a portion of the bottom vertical portion 23.
[0135] like FIG. 9B and FIG. 9C As shown, in this embodiment, the bottom period BP is defined by the distance between the centers of two adjacent bottom center gaps 20G, and the distance BD between the centers of the bottom horizontal portions 21 (i.e., the sum of the widths BG and BW of the bottom center gaps 20G) is approximately 0.57 to approximately 0.69 bottom periods BP. Similarly, in this embodiment, the distance BD between the centers of the bottom vertical portions 23 (i.e., the sum of the widths BG and BW of the bottom center gaps 20G) is approximately 0.57 to approximately 0.69 bottom periods BP.
[0136] exist FIG. 9B In the embodiment, the width BG of the bottom center gap 20G is about 140 nanometers, the width BL is about 220 nanometers, the width BW is about 135 nanometers, and the distance BD between the centers of the bottom horizontal portions 21 (or between the centers of the bottom vertical portions 23) is about 280 nanometers, but the embodiments disclosed herein are not limited thereto.
[0137] exist FIG. 9C In the embodiment, the width BG of the bottom center gap 20G is about 142 nanometers, the width BL is about 143 nanometers, the width BW is about 88 nanometers, and the distance BD between the centers of the bottom horizontal portions 21 (or between the centers of the bottom vertical portions 23) is about 230 nanometers, but the embodiments disclosed herein are not limited thereto.
[0138] It should be noted that the aforementioned diffraction element 10P and absorption element 20P can be combined in various ways. For example, FIG. 2A The diffraction element 10P shown can be set in FIG. 6A , FIG. 7A , FIG. 8Aor FIG. 9A Above the absorption element 20P shown. Similarly, FIG. 3A The diffraction element 10P shown can be set in FIG. 6A , FIG. 7A , FIG. 8A or FIG. 9A Above the absorption element 20P shown. FIG. 4A The diffraction element 10P shown can be set in FIG. 6A , FIG. 7A , FIG. 8A or FIG. 9A Above the absorption element 20P shown. FIG. 5A The diffraction element 10P shown can be set in FIG. 6A , FIG. 7A , FIG. 8A or FIG. 9A Above the absorption element 20P shown.
[0139] Back FIG. 1 In some embodiments, the solid-state image sensor 100 further includes an intermediate layer 30 disposed between the diffraction layer 10 and the absorption layer 20, with each pixel P corresponding to a portion of the intermediate layer 30 (i.e., FIG. 1 (A portion of the intermediate layer 30 is shown). Furthermore, in some embodiments, the absorption layer 20 is disposed at the bottom of the intermediate layer 30. In other words, the absorption layer 20 is embedded at the bottom of the intermediate layer 30, but this disclosure is not limited thereto. In some embodiments, the intermediate layer 30 is a color filter layer. For example, the intermediate layer 30 may be a red filter layer, a green filter layer, or a blue filter layer. Alternatively, the intermediate layer 30 may be a yellow filter layer, a white filter layer, or a cyan filter layer. In other embodiments, there is no intermediate layer 30 between the diffraction layer 10 and the absorption layer 20, and this solid-state image sensor can be applied to an infrared-pass (IR-pass) solid-state image sensor.
[0140] FIG. 10 This is a partial cross-sectional view of a solid-state image sensor 100 according to some other embodiments of the present disclosure. It should be noted that, for the sake of brevity, FIG. 10 Some components of the solid-state image sensor 100 have been omitted.
[0141] Reference FIG. 10 In some embodiments, the solid-state image sensor 100 includes a semiconductor substrate 41. The semiconductor substrate 41 may be a wafer or a chip. For example, the semiconductor substrate 41 may include silicon, but this disclosure is not limited thereto. In some embodiments, the semiconductor substrate 41 has a plurality of photoelectric conversion elements (not shown).
[0142] Photoelectric conversion elements can be used to receive light of different colors. For example, photoelectric conversion elements can be used to receive red light, green light, or blue light, but the embodiments disclosed herein are not limited thereto. Semiconductor substrate 41 may have other photoelectric conversion elements that can be used to receive yellow light, white light, cyan light, or IR / NIR light, and can be adjusted according to actual needs.
[0143] Reference FIG. 10 In some embodiments, the solid-state image sensor 100 includes an absorption layer 20 and a diffraction layer 10, with the absorption layer 20 disposed above the semiconductor substrate 41 and the diffraction layer 10 disposed above the absorption layer 20. In this embodiment, the solid-state image sensor 100 also includes an intermediate layer 30 disposed between the diffraction layer 10 and the absorption layer 20. In some embodiments, the thickness T of the intermediate layer 30 is approximately 200 nanometers to approximately 500 nanometers.
[0144] Reference FIG. 10 In some embodiments, the solid-state image sensor 100 further includes a light-concentrating structure 45 disposed above the diffraction layer 10. In this embodiment, the light-concentrating structure 45 may be a microlens structure, such as a semi-convex lens or a convex lens, but the embodiments disclosed herein are not limited thereto. In addition, the solid-state image sensor 100 includes a spatial layer 43 disposed between the diffraction layer 10 and the light-concentrating structure 45.
[0145] FIG. 11 The transmission spectra of solid-state image sensors according to comparative examples (R_REF) and embodiments of the present disclosure (R_META) are shown when the intermediate layer 30 is a red filter layer with a thickness of about 300 nanometers. FIG. 12 The transmission spectrum of the solid-state image sensor according to the comparative example (G_REF) and the embodiment of the present disclosure (G_META) is shown when the intermediate layer 30 is a green filter layer with a thickness of about 300 nanometers. FIG. 13 The transmission spectra of solid-state image sensors according to comparative example (B_REF) and embodiments of the present disclosure (B_META) are shown when the intermediate layer 30 is a blue filter layer with a thickness of approximately 300 nanometers. Here, the solid-state image sensor of the present disclosure embodiment may have the same characteristics as... FIG. 10 The solid-state image sensor 100 shown has the same or similar structure, while the solid-state image sensor of the comparative example does not include the diffraction layer 10 and the absorption layer 20.
[0146] like FIG. 11 to FIG. 13 FIG. 10 FIG. 11 to FIG. 13As shown, compared to the solid-state image sensor of the comparative example, the solid-state image sensor of this disclosure embodiment can have higher sensing contrast. Furthermore, the solid-state image sensor of this disclosure embodiment can have improved SNR performance (e.g., an increase of 5%) and reduced crosstalk (e.g., reduced from 21% to 10% at 530 nm). In addition, the height of the color filter layer can be shortened while maintaining high color performance.
[0147] The foregoing outlines features of several embodiments 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 given above with reference to several embodiments, it is not intended to limit the scope of this disclosure.
[0148] References to features, advantages, or similar language throughout this specification do not 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.
[0149] Furthermore, in one or more embodiments, the features, advantages, and characteristics described herein 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 some embodiments that may not be present in all embodiments of this disclosure.
Claims
1. A solid-state image sensor, comprising: A diffraction layer comprising a plurality of diffraction elements, wherein the plurality of diffraction elements have a plurality of top center gaps; as well as An absorption layer is disposed below the diffraction layer and includes a plurality of absorption elements, wherein the plurality of absorption elements have a plurality of bottom center gaps; The solid-state image sensor has multiple pixels defined by multiple diffraction elements and multiple absorption elements, and the multiple pixels are arranged in an array, with each top center gap corresponding to one of the multiple bottom center gaps and one of the multiple pixels.
2. The solid-state image sensor of claim 1, wherein, in a top view, each of the diffraction elements or each of the absorption elements is formed as a split cross, a hollow cross, a split rectangular grid, or a hollow rectangular block.
3. The solid-state image sensor of claim 2, wherein in the top view, each of the diffraction elements has two top horizontal portions arranged along a first direction and two top vertical portions arranged along a second direction perpendicular to the first direction, each top center gap being defined by the two top horizontal portions and the two top vertical portions, each top vertical portion being formed as a rectangle having a first width in the first direction and a second width in the second direction, and the first width being less than the sum of the width of each top center gap and the second width.
4. The solid-state image sensor of claim 3, wherein the width of each of the top center gaps is greater than the first width, the first width is less than the second width, a top period is defined by the distance between the centers of two adjacent top center gaps, and the distance between the centers of two top horizontal portions is 0.60 to 0.86 of the top periods.
5. The solid-state image sensor of claim 3, wherein the width of each of the top center gaps is greater than the first width, the first width is greater than the second width, a top period is defined by the distance between the centers of two adjacent top center gaps, and the distance between the centers of two top horizontal portions is 0.63 to 0.77 of the top periods.
6. The solid-state image sensor of claim 3, wherein the width of each of the top center gaps is less than the first width, the first width is less than the second width, a top period is defined by the distance between the centers of two adjacent top center gaps, and the distance between the centers of two top horizontal portions is 0.52 to 0.91 of the top periods.
7. The solid-state image sensor of claim 3, wherein the width of each of the top center gaps is less than the first width, the first width is greater than the second width, a top period is defined by the distance between the centers of two adjacent top center gaps, and the distance between the centers of two top horizontal portions is 0.61 to 0.69 of the top periods.
8. The solid-state image sensor of claim 2, wherein in the top view, each of the absorbing elements has two bottom horizontal portions arranged along a first direction and two bottom vertical portions arranged along a second direction perpendicular to the first direction, each bottom center gap is defined by the two bottom horizontal portions and the two bottom vertical portions, each bottom vertical portion is formed as a rectangle having a third width in the first direction and a fourth width in the second direction, and the third width is less than the sum of the width of each bottom center gap and the fourth width.
9. The solid-state image sensor of claim 8, wherein the width of each bottom center gap is greater than the third width, the third width is less than the fourth width, a bottom period is defined by the distance between the centers of two adjacent bottom center gaps, and the distance between the centers of two bottom horizontal portions is 0.60 to 0.71 of the bottom periods.
10. The solid-state image sensor of claim 8, wherein the width of each bottom center gap is greater than the third width, the third width is greater than the fourth width, a bottom period is defined by the distance between the centers of two adjacent bottom center gaps, and the distance between the centers of two bottom horizontal portions is 0.42 to 0.77 of the bottom periods.
11. The solid-state image sensor of claim 8, wherein the width of each bottom center gap is less than the third width, the third width is less than the fourth width, a bottom period is defined by the distance between the centers of two adjacent bottom center gaps, and the distance between the centers of two bottom horizontal portions is 0.60 to 0.95 of the bottom periods.
12. The solid-state image sensor of claim 8, wherein the width of each bottom center gap is less than the third width, the third width is greater than the fourth width, a bottom period is defined by the distance between the centers of two adjacent bottom center gaps, and the distance between the centers of two bottom horizontal portions is 0.57 to 0.69 of the bottom periods.
13. The solid-state image sensor of claim 1, further comprising: An intermediate layer is disposed between the diffraction layer and the absorption layer, wherein each pixel corresponds to a portion of the intermediate layer; and A light-gathering structure is positioned above the diffraction layer. The intermediate layer is a color filter layer, and the absorption layer is embedded at the bottom of the intermediate layer.
14. The solid-state image sensor of claim 1, wherein the diffraction element comprises tantalum pentoxide, and the absorption element comprises titanium dioxide, titanium, gold, silver, silicon, silicon nitride, graphene, copper, bismuth, palladium, platinum, aluminum, carbon, titanium nitride, aluminum aluminum nitride, amorphous silicon, or a combination thereof.