Spectral filter, image sensor and electronic device comprising a spectral filter

Abstract

A spectral filter, and an image sensor and an electronic device each including the spectral filter are provided. The spectral filter includes at least one first filter having a center wavelength in a first wavelength region, and at least one second filter having a center wavelength in a second wavelength region. The first filter includes a plurality of first metal reflection layers vertically spaced apart from each other, and at least one first cavity provided between the plurality of first metal reflection layers. The second filter includes a second metal reflection layer and a Bragg reflection layer vertically spaced apart from each other, and at least one second cavity provided between the second metal reflection layer and the Bragg reflection layer.

Description

[0001] Cross-references to related applications

[0002] This application is based on and claims priority to Korean Patent Application No. 10-2021-0052535 filed with the Korean Intellectual Property Office on April 22, 2021, and Korean Patent Application No. 10-2022-0030947 filed with the Korean Intellectual Property Office on March 11, 2022, the entire disclosure of which is incorporated herein by reference. Technical Field

[0003] This disclosure relates to a spectral filter, and image sensors and electronic devices, each including the spectral filter. Background Technology

[0004] In related technologies, image sensors divide the wavelength band into three parts: red (R), green (G), and blue (B). However, to improve the accuracy of color reproduction and object recognition performance, it is necessary to develop image sensors with spectral filters that divide the wavelength band into even more parts. Existing spectral filters are already used in dedicated cameras that include large and complex optical components, and research and development on technologies for integrating spectral filters onto semiconductor chips in image sensors is ongoing. Summary of the Invention

[0005] A spectral filter is provided, as well as an image sensor and an electronic device, each including the spectral filter.

[0006] Additional aspects will be set forth in part in the description which follows, and will also be apparent in part from the description, or may be learned by practicing the embodiments presented in this disclosure.

[0007] According to one aspect of the embodiments, a spectral filter includes: at least one first filter having a center wavelength in a first wavelength region; and at least one second filter having a center wavelength in a second wavelength region, wherein the first filter includes: a plurality of first metal reflective layers vertically spaced apart from each other; and at least one first cavity disposed between the plurality of first metal reflective layers; and the second filter includes: a second metal reflective layer and a Bragg reflective layer vertically spaced apart from each other; and at least one second cavity disposed between the second metal reflective layer and the Bragg reflective layer.

[0008] The center wavelength in the first wavelength region may be shorter than the center wavelength in the second wavelength region. In this case, the first metal reflective layer may include Al, Ag, Au, Ti, W, or TiN, and the second metal reflective layer may include Cu, Ag, Au, Ti, W, or TiN. The second metal reflective layer may also include polycrystalline silicon.

[0009] The first and second metal reflective layers can have a thickness of approximately 10 nm to approximately 80 nm.

[0010] The Bragg reflector may have a structure in which at least one first material layer and at least one second material layer with different refractive indices are stacked alternately.

[0011] At least one first filter can form a first filter array comprising a plurality of first filters having different center wavelengths, and at least one second filter can form a second filter array comprising a plurality of second filters having different center wavelengths.

[0012] The center wavelength of the first filter can be adjusted by changing the thickness or effective refractive index of the first cavity, and the center wavelength of the second filter can be adjusted by changing the thickness or effective refractive index of the second cavity.

[0013] The first filter may further include a first dielectric layer and a second dielectric layer respectively disposed below and above the first cavity, and the second filter may further include a third dielectric layer and a fourth dielectric layer respectively disposed below and above the second cavity.

[0014] Each of the first to fourth dielectric layers can have a single-layer or multi-layer structure.

[0015] The thickness or effective refractive index of each of the first and second dielectric layers can be adjusted according to the center wavelength of the first filter, and the thickness or effective refractive index of each of the third and fourth dielectric layers can be adjusted according to the center wavelength of the second filter.

[0016] The spectral filter may also include multiple microlenses disposed at at least one first filter and at least one second filter.

[0017] The spectral filter may also include a color filter disposed in the same plane as at least one first filter and at least one second filter.

[0018] The spectral filter may also include an additional filter disposed at at least one first filter and at least one second filter and transmitting a specific wavelength band. The additional filter may include a color filter or a broadband filter.

[0019] A short-wavelength absorption filter may be disposed at a portion of at least one first filter and at least one second filter, and a long-wavelength cutoff filter may be disposed at another portion of at least one first filter and at least one second filter.

[0020] According to one aspect of another embodiment, an image sensor includes: a spectral filter; and a pixel array for receiving light transmitted through the spectral filter, wherein the spectral filter includes: at least one first filter having a center wavelength in a first wavelength region; and at least one second filter having a center wavelength in a second wavelength region, wherein the first filter includes: a plurality of first metallic reflective layers vertically spaced apart from each other; and at least one first cavity disposed between the plurality of first metallic reflective layers; and the second filter includes: a second metallic reflective layer and a Bragg reflective layer vertically spaced apart from each other; and at least one second cavity disposed between the second metallic reflective layer and the Bragg reflective layer.

[0021] The pixel array may include multiple pixels, and each pixel may include a wiring layer, which includes driving circuitry and a photodiode disposed on the wiring layer.

[0022] The center wavelength in the first wavelength region can be shorter than the center wavelength in the second wavelength region.

[0023] The Bragg reflector may have a structure in which at least one first material layer and at least one second material layer with different refractive indices are stacked alternately.

[0024] At least one first filter can form a first filter array comprising a plurality of first filters having different center wavelengths, and at least one second filter can form a second filter array comprising a plurality of second filters having different center wavelengths.

[0025] The center wavelength of the first filter can be adjusted by changing the thickness or effective refractive index of the first cavity, and the center wavelength of the second filter can be adjusted by changing the thickness or effective refractive index of the second cavity.

[0026] The first filter may further include a first dielectric layer and a second dielectric layer respectively disposed below and above the first cavity, and the second filter may further include a third dielectric layer and a fourth dielectric layer respectively disposed below and above the second cavity.

[0027] The thickness or effective refractive index of each of the first and second dielectric layers can be adjusted according to the center wavelength of the first filter, and the thickness or effective refractive index of each of the third and fourth dielectric layers can be adjusted according to the center wavelength of the second filter.

[0028] The spectral filter may also include multiple microlenses disposed at at least one first filter and at least one second filter.

[0029] The spectral filter may also include a color filter disposed in the same plane as at least one first filter and at least one second filter.

[0030] The spectral filter may also include an additional filter disposed at at least one first filter and at least one second filter and transmitting a specific wavelength band.

[0031] Image sensors may also include timing controllers, line decoders, and output circuitry.

[0032] An electronic device comprising the aforementioned image sensor.

[0033] Electronic devices may include mobile phones, smartphones, tablets, smart tablets, digital cameras, camcorders, laptops, televisions, smart TVs, smart refrigerators, security cameras, robots, or medical cameras.

[0034] According to one aspect of yet another embodiment, a spectral filter is disclosed, comprising: a first filter having a center wavelength in a first wavelength region; and a second filter having a center wavelength in a second wavelength region, wherein the first filter comprises: two first metallic reflective layers vertically spaced apart from each other; and a first cavity disposed between the two first metallic reflective layers, and the second filter comprises: a second metallic reflective layer and a Bragg reflective layer vertically spaced apart from each other; and a second cavity disposed between the second metallic reflective layer and the Bragg reflective layer, wherein the second metallic reflective layer and the Bragg reflective layer are made of different materials.

[0035] According to one aspect of an embodiment, an image sensor includes: a spectral filter; and a pixel array for receiving light transmitted through the spectral filter, wherein the spectral filter includes: a first filter having a center wavelength in a first wavelength region; and a second filter having a center wavelength in a second wavelength region, wherein the first filter includes: a plurality of first metallic reflective layers vertically spaced apart from each other; and a first cavity disposed between the plurality of first metallic reflective layers, and the second filter includes: a second metallic reflective layer and a Bragg reflective layer vertically spaced apart from each other; and a cavity disposed between the second metallic reflective layer and the Bragg reflective layer. The second cavity between the two, wherein a plurality of first metal reflective layers include Al, Ag, Au, Ti, W or TiN, and the second metal reflective layer includes Cu, wherein the first filter further includes a first dielectric layer and a second dielectric layer respectively disposed below and above the first cavity, and the second filter further includes a third dielectric layer and a fourth dielectric layer respectively disposed below and above the second cavity, and wherein the center wavelength of the first filter is based on the thickness or effective refractive index of each of the first and second dielectric layers, and the center wavelength of the second filter is based on the thickness or effective refractive index of each of the third and fourth dielectric layers. Attached Figure Description

[0036] The above and other aspects, features, and advantages of some embodiments of this disclosure will become clearer from the following description taken in conjunction with the accompanying drawings, in which:

[0037] FIG. 1 This is a schematic cross-sectional view of an image sensor according to an example embodiment;

[0038] FIG. 2 This is a cross-sectional view of a spectral filter according to an example embodiment;

[0039] FIG. 3A This is a schematic diagram of a filter containing a TiO2 cavity between Cu reflective layers;

[0040] FIG. 3B It includes setting up separately FIG. 3A A schematic diagram of the filter with TiO2 dielectric layers above and below the structure;

[0041] FIG. 4 It shows FIG. 3A filters and FIG. 3B The transmission spectrum of the filter;

[0042] FIG. 5 This is a schematic cross-sectional view of a spectral filter according to another example embodiment;

[0043] FIG. 6 It shows FIG. 5 The transmission spectrum of the spectral filter;

[0044] FIG. 7 This is a schematic cross-sectional view of a spectral filter according to another example embodiment;

[0045] FIG. 8 It shows FIG. 7 The transmission spectrum of the spectral filter;

[0046] FIG. 9 This is a schematic cross-sectional view of a spectral filter according to another example embodiment;

[0047] FIG. 10 This is a schematic cross-sectional view of a spectral filter according to another example embodiment;

[0048] FIG. 11 This is a schematic cross-sectional view of a spectral filter according to another example embodiment;

[0049] FIG. 12 This is a schematic cross-sectional view of a spectral filter according to another example embodiment;

[0050] FIG. 13 This is a schematic cross-sectional view of a spectral filter according to another example embodiment;

[0051] FIG. 14 This is a schematic cross-sectional view of a spectral filter according to another example embodiment;

[0052] FIG. 15 This is a schematic cross-sectional view of a spectral filter according to another example embodiment;

[0053] FIG. 16 It shows FIG. 15 The transmission spectrum of the spectral filter;

[0054] FIG. 17 This is a schematic cross-sectional view of a spectral filter according to another example embodiment;

[0055] FIG. 18A and FIG. 18B The filter structure including Cu metal layers below and above the cavity and the transmission spectrum of this filter structure are shown respectively;

[0056] FIG. 19A and FIG. 19B The filter structure including Si / SiO2 Bragg reflector layers below and above the cavity and the transmission spectrum of this filter structure are shown respectively;

[0057] FIG. 20A and FIG. 20B The filter structure, including a Cu reflective layer below the cavity and a Si / SiO2 Bragg reflective layer above the cavity, and the transmission spectrum of this filter structure are shown respectively.

[0058] FIG. 21 This is a schematic cross-sectional view of a spectral filter according to another example embodiment;

[0059] FIG. 22 This is a schematic cross-sectional view of a spectral filter according to another example embodiment;

[0060] FIG. 23 This is a schematic cross-sectional view of a spectral filter according to another example embodiment;

[0061] FIG. 24 This is a schematic cross-sectional view of a spectral filter according to another example embodiment;

[0062] FIG. 25 This is a schematic cross-sectional view of a spectral filter according to another example embodiment;

[0063] FIG. 26 This is a schematic cross-sectional view of a spectral filter according to another example embodiment;

[0064] FIG. 27 This is a schematic cross-sectional view of a spectral filter according to another example embodiment;

[0065] FIG. 28 It can be used as FIG. 27 A diagram showing an example of a broadband filter with an additional filter;

[0066] FIG. 29 It can be used as FIG. 27 A diagram of another example of a broadband filter with an additional filter;

[0067] FIG. 30 This is a schematic cross-sectional view of a spectral filter according to another example embodiment;

[0068] FIG. 31 This is a block diagram of an image sensor according to an example embodiment;

[0069] FIG. 32 It is applicable FIG. 31 A plan view of an example spectral filter for an image sensor;

[0070] FIG. 33 It is applicable FIG. 31 A plan view of another example of a spectral filter for an image sensor;

[0071] FIG. 34 It is applicable FIG. 31 A plan view of another example of a spectral filter for an image sensor;

[0072] FIG. 35 This is a schematic block diagram of an electronic device including an image sensor according to an example embodiment;

[0073] FIG. 36 yes FIG. 35 A schematic block diagram of the camera module; and

[0074] FIG. 37 to FIG. 38 These are figures illustrating various examples of electronic devices using image sensors according to exemplary embodiments. Detailed Implementation

[0075] Referring now to the embodiments, examples of which are illustrated in the accompanying drawings, wherein similar reference numerals throughout the drawings denote similar elements. In this respect, the presented embodiments may take different forms and should not be construed as limited to the description set forth herein. Therefore, the embodiments are described below only with reference to the accompanying drawings to explain various aspects. The term “and / or” as used herein includes any and all combinations of one or more of the associated listed items. Expressions such as “at least one of…” modify the entire list of elements when following a list of elements, rather than modifying individual elements in the list. For example, the expression “at least one of a, b, and c” should be understood to include only a, only b, only c, both a and b, both a and c, both b and c, all of a, b, and c, or variations thereof.

[0076] In the context of describing the embodiments (especially in the context of the appended claims), the terms “a,” “an,” “the,” and similar designations will be interpreted to cover both the singular and the plural. Unless otherwise stated herein or clearly contradicted by the context, the operation of all methods described herein can be performed in any suitable order, and the embodiments are not limited to the described order of operation.

[0077] In addition, the terms "component," "module," etc., refer to a unit that performs at least one function or operation and can be implemented by hardware, software, or a combination thereof.

[0078] The connecting lines or connectors shown in the various figures are intended to represent exemplary functional relationships and / or physical or logical couplings between various components. Therefore, it should be noted that many alternative or additional functional relationships, physical connections or logical connections may exist in actual devices.

[0079] Unless otherwise stated, the use of any and all examples or exemplary language provided herein is intended only to better illustrate technical ideas and does not constitute a limitation on the scope of the embodiments.

[0080] FIG. 1 This is a cross-sectional schematic diagram of an image sensor 1000 according to an example embodiment. FIG. 1 The image sensor 1000 may include, for example, a complementary metal-oxide-semiconductor (CMOS) image sensor or a charge-coupled device (CCD) image sensor.

[0081] refer to FIG. 1 The image sensor 1000 may include a pixel array 65 and a resonator structure 80 disposed on the pixel array 65. The pixel array 65 may include a plurality of pixels arranged in a two-dimensional (2D) manner, and the resonator structure 80 may include a plurality of resonators disposed corresponding to the plurality of pixels. FIG. 1The illustration shows a pixel array 65 comprising four pixels and a resonator structure 80 comprising four resonators.

[0082] Each pixel of the pixel array 65 may include a photodiode 62 as a photoelectric conversion element and a driving circuit 52 for driving the photodiode 62. The photodiode 62 may be embedded in a semiconductor substrate 61. The semiconductor substrate 61 may be, for example, a silicon substrate. However, this disclosure is not limited thereto. A wiring layer 51 may be provided on the lower surface 61a of the semiconductor substrate 61, and a driving circuit 52, such as a metal-oxide-semiconductor field-effect transistor (MOSFET), may be provided in the wiring layer 51.

[0083] A resonator structure 80, comprising multiple resonators, may be disposed above a semiconductor substrate 61. Each resonator may be configured to transmit light in a specific desired wavelength region. Each resonator may include a first reflective layer 81 and a second reflective layer 82 spaced apart from each other, and cavities 83a, 83b, 83c, and 83d disposed between the first reflective layer 81 and the second reflective layer 82. Each of the first reflective layer 81 and the second reflective layer 82 may include, for example, a metallic reflective layer or a Bragg reflective layer. Each of the cavities 83a, 83b, 83c, and 83d may be configured to induce resonance of light in a specific desired wavelength region.

[0084] A first functional layer 71 may be disposed between the upper surface 61b of the semiconductor substrate 61 and the resonator structure 80. The first functional layer 71 may improve the transmittance of light incident through the resonator structure 80 toward the photodiode 62. For this purpose, the first functional layer 71 may include a dielectric layer or dielectric pattern with an adjusted refractive index.

[0085] A second functional layer 72 may be disposed on the upper surface of the resonator structure 80. The second functional layer 72 can improve the transmittance of light incident toward the resonator structure 80. For this purpose, the second functional layer 72 may include a dielectric layer or dielectric pattern with an adjusted refractive index. A third functional layer 90 may further be disposed on the upper surface of the second functional layer 72. The third functional layer 90 may include, for example, an anti-reflective layer, a focusing lens, a color filter, a short-wavelength absorption filter, a long-wavelength cutoff filter, etc. However, this is only an example.

[0086] At least one of the first to third functional layers 71, 72 and 90 can, together with the resonator structure 80, constitute the spectral filter described below. The spectral filter according to the example embodiment will be described in detail below.

[0087] FIG. 2 This is a cross-sectional view of a spectral filter according to an example embodiment.

[0088] refer to FIG. 2The spectral filter 1100 may include multiple filters arranged in a 2D manner. FIG. 2 Cross-sectional views of six filters (i.e., first filter 111, second filter 112, third filter 113, fourth filter 121, fifth filter 122 and sixth filter 123) as examples are shown.

[0089] The spectral filter 1100 may include a first filter array 110 and a second filter array 120 disposed on a plane. Although the first filter array 110 and the second filter array 120 may be disposed on substantially the same plane, this disclosure is not limited thereto. The first filter array 110 may include at least one filter having a center wavelength in a first wavelength region. The range of the first wavelength region can be, for example, from about 250 nm to about 600 nm. However, this is merely exemplary, and the first wavelength region may also have various wavelength ranges depending on design considerations. FIG. 2 The first filter array 110 is shown to include first filters to third filters 111, 112 and 113.

[0090] The second filter array 120 may include at least one filter having a center wavelength in a second wavelength region. The second wavelength region may be longer than the first wavelength region. For example, the range of the second wavelength region may be from approximately 600 nm to approximately 1100 nm. However, this is merely exemplary, and the second wavelength region may also have various wavelength ranges depending on design considerations. FIG. 2 The second filter array 120 is shown to include fourth to sixth filters 121, 122 and 123.

[0091] although FIG. 2 The illustration shows a first filter array 110 comprising three filters (i.e., first filters to third filters 111, 112, and 113) and a second filter array 120 comprising three filters (i.e., fourth filters to sixth filters 121, 122, and 123). However, this illustration is merely an example, and the number of filters constituting the first filter array 110 and the second filter array 120, respectively, can vary.

[0092] Each of the first to third filters 111, 112 and 113 constituting the first filter array 110 can transmit a specific center wavelength in the first wavelength region and has a Fabry-Perot structure, wherein a cavity (i.e., the first cavity 141, the second cavity 142 or the third cavity 143) is disposed between two first metal reflective layers 131 and 132 spaced apart from each other.

[0093] When light passes through the first metal reflective layers 131 and 132 and is incident on cavities 141, 142, or 143, the light can be internally reflected within cavities 141, 142, or 143 between the first metal reflective layers 131 and 132, during which constructive and destructive interference occur. Light with a specific center wavelength and satisfying the constructive interference condition can exit outside the filters (i.e., the first filter 111, the second filter 112, or the third filter 113). The wavelength and center wavelength of the light passing through filters 111, 112, or 113 can be determined based on the reflection bands of the first metal reflective layers 131 and 132 and the characteristics of cavities 141, 142, or 143.

[0094] The first metal reflective layers 131 and 132 may comprise a first metal capable of reflecting light in a first wavelength region. For example, the first metal may comprise Al, Ag, Au, Ti, W, TiN, etc. However, this disclosure is not limited thereto. Although the first metal reflective layers 131 and 132 may have a thickness of tens of nanometers, this is merely exemplary. For example, the first metal reflective layers 131 and 132 may have a thickness of approximately 10 nm to approximately 80 nm. In particular, the first metal reflective layers 131 and 132 may have a thickness of approximately 10 nm to approximately 30 nm.

[0095] The first to third cavities 141, 142, and 143 disposed between the first metallic reflective layers 131 and 132 may comprise dielectric materials having a specific refractive index as resonant layers. For example, the first to third cavities 141, 142, and 143 may comprise silicon, silicon oxide, silicon nitride, hafnium oxide, or titanium oxide. However, this disclosure is not limited thereto.

[0096] The first to third filters 111, 112 and 113 can have different center wavelengths in the first wavelength region. For this purpose, the first filter 111, the second filter 112 and the third filter 113 can each include a first cavity 141, a second cavity 142 and a third cavity 143 with different thicknesses. FIG. 2 The diagram illustrates a case where the second cavity 142 is thicker than the first cavity 141, and the third cavity 143 is thicker than the second cavity 142. In this case, among the first to third filters 111, 112, and 113, the third filter 113 can have the longest center wavelength, while the first filter 111 can have the shortest center wavelength. Furthermore, depending on the cavity thickness, some filters can have multiple center wavelengths.

[0097] Each of the fourth to sixth filters 121, 122, and 123 constituting the second filter array 120 can transmit a specific center wavelength in the second wavelength region and has a Fabry-Perot structure, wherein a cavity (i.e., the fourth cavity 161, the fifth cavity 162, or the sixth cavity 163) is disposed between two second metallic reflective layers 151 and 152 spaced apart from each other. The band and center wavelength of light passing through the filter (i.e., the fourth filter 121, the fifth filter 122, or the sixth filter 123) can be determined based on the reflection bands of the second metallic reflective layers 151 and 152 and the characteristics of the cavities 161, 162, or 163.

[0098] The second metal reflective layers 151 and 152 may comprise a second metal capable of reflecting light in a second wavelength region. For example, the second metal may include Cu, Ag, Au, Ti, W, Tin, etc. However, this disclosure is not limited thereto. In addition to the second metal, the second metal reflective layers 151 and 152 may also comprise polycrystalline silicon. Although the second metal reflective layers 151 and 152 may have a thickness of tens of nanometers, this is merely exemplary. For example, the second metal reflective layers 151 and 152 may have a thickness of approximately 10 nm to approximately 80 nm. In particular, the second metal reflective layers 151 and 152 may have a thickness of approximately 40 nm to approximately 50 nm.

[0099] The second metal constituting the second metal reflective layers 151 and 152 can be a different metal from the first metal constituting the first metal reflective layers 131 and 132. For example, when the first metal reflective layers 131 and 132 comprise Al, the second metal reflective layers 151 and 152 can comprise Cu. Furthermore, for example, when the first metal reflective layers 131 and 132 comprise Al, the second metal reflective layers 151 and 152 can comprise Ag. Furthermore, for example, when the first metal reflective layers 131 and 132 comprise Ag, the second metal reflective layers 151 and 152 can comprise Cu.

[0100] The fourth to sixth cavities 161, 162, and 163 disposed between the second metal reflective layers 151 and 152 may comprise a dielectric material having a specific refractive index as a resonant layer. For example, the fourth to sixth cavities 161, 162, and 163 may comprise silicon, silicon oxide, silicon nitride, hafnium oxide, or titanium oxide.

[0101] The fourth to sixth cavities 161, 162, and 163 disposed between the second metal reflective layers 151 and 152 may contain the same material as the first to third cavities 141, 142, and 143 disposed between the first metal reflective layers 131 and 132. In this case, the thickness of the fourth to sixth cavities 161, 162, and 163 disposed between the second metal reflective layers 151 and 152 may be different from the thickness of the first to third cavities 141, 142, and 143 disposed between the first metal reflective layers 131 and 132. The fourth to sixth cavities 161, 162, and 163 disposed between the second metal reflective layers 151 and 152 may contain a material different from the material contained in the first to third cavities 141, 142, and 143 disposed between the first metal reflective layers 131 and 132.

[0102] The fourth to sixth filters 121, 122 and 123 can have different center wavelengths in the second wavelength region. For this purpose, the fourth filter 121, the fifth filter 122 and the sixth filter 123 can respectively include a fourth cavity 161, a fifth cavity 162 and a sixth cavity 163 with different thicknesses. FIG. 2 The diagram illustrates a case where the fifth cavity 162 is thicker than the fourth cavity 161, and the sixth cavity 163 is thicker than the fifth cavity 162. In this case, among the fourth to sixth filters 121, 122, and 123, the sixth filter 123 can have the longest center wavelength, while the fourth filter 121 can have the shortest center wavelength. Furthermore, depending on the cavity thickness, some filters can have multiple center wavelengths.

[0103] As described above, by arranging the first filter array 110 (where the first to third cavities 141, 142 and 143 are disposed between the first metal reflective layers 131 and 132) and the second filter array 120 (where the fourth to sixth cavities 161, 162 and 163 are disposed between the second metal reflective layers 151 and 152) on a plane, a spectral filter having broadband characteristics including a first wavelength region and a second wavelength region (e.g., a wavelength range from ultraviolet light to near-infrared light) can be realized.

[0104] FIG. 3A This is a schematic diagram of a filter 11 containing a TiO2 cavity between Cu reflective layers. FIG. 3B It includes setting up separately FIG. 3A A schematic diagram of the filter 21 with TiO2 dielectric layers above and below the structure.

[0105] FIG. 4 It shows FIG. 3A Filter 11 and FIG. 3B The transmission spectrum of filter 21. FIG. 4 In the text, "A" represents... FIG. 3AThe transmission spectrum of filter 11, where "B" indicates FIG. 3B The transmission spectrum of filter 21. Reference FIG. 4 , FIG. 3B The filter 21 has a higher density than FIG. 3A The filter 11 has high transmittance.

[0106] Therefore, by further depositing TiO2 dielectric layers above and below the structure in which the TiO2 cavity is disposed between the Cu reflective layers, a filter 21 with improved transmittance can be realized. Here, the thickness of the TiO2 dielectric layer can be adjusted according to the center wavelength of the filter 21.

[0107] FIG. 5 This is a schematic cross-sectional view of a spectral filter 1200 according to another example embodiment.

[0108] refer to FIG. 5 The first filter array 210 may include a first filter 211, a second filter 212, and a third filter 213 having a center wavelength in a first wavelength region. The second filter array 220 may include a fourth filter 221, a fifth filter 222, and a sixth filter 223 having a center wavelength in a second wavelength region.

[0109] Each of the first to third filters 211, 212, and 213 constituting the first filter array 210 may include two first metal reflective layers 131 and 132 spaced apart from each other, a cavity 141, 142, or 143 disposed between the first metal reflective layers 131 and 132, and a first dielectric layer 171 and a second dielectric layer 172 disposed below and above the cavities 141, 142, or 143, respectively. The first filter 211, the second filter 212, and the third filter 213 may each include a first cavity 141, a second cavity 142, and a third cavity 143 with different thicknesses, such that the first to third filters 211, 212, and 213 have different center wavelengths in a first wavelength region. The description of the first metal reflective layers 131 and 132 and the first to third cavities 141, 142, and 143 has been provided above.

[0110] A first dielectric layer 171 may be disposed below the first metal reflective layer 131, and a second dielectric layer 172 may be disposed above the first metal reflective layer 132. The first dielectric layer 171 and the second dielectric layer 172 can improve the transmittance of the first to the third filters 211, 212, and 213. The first dielectric layer 171 and the second dielectric layer 172 may have a single-layer structure. Each of the first dielectric layer 171 and the second dielectric layer 172 may include, for example, titanium oxide, silicon nitride, hafnium oxide, silicon oxide, high refractive index polymers, etc. However, the foregoing is provided only as an example.

[0111] The thickness of the first dielectric layer 171 and the second dielectric layer 172 can vary according to the center wavelength of the first filter to the third filter 211, 212 and 213. FIG. 5 The thickness of the first dielectric layer 171 and the second dielectric layer 172 is shown to increase with the center wavelength of the first filter to the third filter 211, 212 and 213. The thickness of each of the first dielectric layer 171 and the second dielectric layer 172 may be from about 10 nm to 20,000 nm; however, this disclosure is not limited thereto.

[0112] Each of the fourth to sixth filters 221, 222, and 223 constituting the second filter array 220 may include two second metallic reflective layers 151 and 152 spaced apart from each other, a cavity 161, 162, or 163 disposed between the second metallic reflective layers 151 and 152, and a third dielectric layer 181 and a fourth dielectric layer 182 disposed below and above the cavities 161, 162, or 163, respectively. The fourth filter 221, the fifth filter 222, and the sixth filter 223 may each include a fourth cavity 161, a fifth cavity 162, and a sixth cavity 163 with different thicknesses, such that the fourth to sixth filters 221, 222, and 223 have different center wavelengths in the second wavelength region. A description of the second metallic reflective layers 151 and 152 and the fourth to sixth cavities 161, 162, and 163 has been provided above.

[0113] The third dielectric layer 181 may be disposed below the second metal reflective layer 151, and the fourth dielectric layer 182 may be disposed above the second metal reflective layer 152. The third dielectric layer 181 and the fourth dielectric layer 182 may improve the transmittance of the fourth to sixth filters 221, 222, and 223. The third dielectric layer 181 and the fourth dielectric layer 182 may have a single-layer structure. Similar to the first dielectric layer 171 and the second dielectric layer 172 described above, each of the third dielectric layer 181 and the fourth dielectric layer 182 may include, for example, titanium oxide, silicon nitride, hafnium oxide, silicon oxide, high refractive index polymers, etc.; however, this disclosure is not limited thereto.

[0114] The thicknesses of the third dielectric layer 181 and the fourth dielectric layer 182 can vary according to the center wavelengths of the fourth to sixth filters 221, 222 and 223. FIG. 5 The thickness of the third dielectric layer 181 and the fourth dielectric layer 182 is shown to increase with the center wavelength of the fourth to sixth filters 221, 222 and 223. The thickness of each of the third dielectric layer 181 and the fourth dielectric layer 182 may be from approximately 10 nm to 20,000 nm; however, this disclosure is not limited thereto.

[0115] FIG. 6 It showsFIG. 5 The transmission spectrum of the spectral filter 1200. Here, the first metal reflective layers 131 and 132 comprise Al, the second metal reflective layers 151 and 152 comprise Cu, and the first to sixth cavities 141, 142, 143, 161, 162, and 163 comprise TiO2. The first to fourth dielectric layers 171, 172, 181, and 182 comprise TiO2. FIG. 6 In the diagram, "C1" represents the transmission spectrum of the first filter array 210, and "C2" represents the transmission spectrum of the second filter array 220.

[0116] FIG. 7 This is a schematic cross-sectional view of a spectral filter 1300 according to another example embodiment.

[0117] refer to FIG. 7 The first filter array 310 may include at least one filter having a center wavelength in a first wavelength region. The second filter array 320 may include at least one filter having a center wavelength in a second wavelength region.

[0118] For convenience, FIG. 7 The diagram illustrates a case where a first filter array 310 includes one filter (i.e., first filter 315) and a second filter array 320 includes one filter (i.e., second filter 325). When each of the first filter array 310 and the second filter array 320 includes multiple filters, these multiple filters may include cavities with different thicknesses.

[0119] The first filter 315 constituting the first filter array 310 may include two first metal reflective layers 131 and 132 spaced apart from each other, a first cavity 145 disposed between the first metal reflective layers 131 and 132, and a first dielectric layer 371 and a second dielectric layer 372 disposed below and above the first cavity 145, respectively.

[0120] The first dielectric layer 371 may be disposed below the first metal reflective layer 131, and the second dielectric layer 372 may be disposed above the first metal reflective layer 132. Each of the first dielectric layer 371 and the second dielectric layer 372 may include titanium oxide, silicon nitride, hafnium oxide, silicon oxide, high refractive index polymer, etc., but this disclosure is not limited thereto.

[0121] The first dielectric layer 371 may have a single-layer structure. However, this disclosure is not limited thereto, and the first dielectric layer 371 may also have a multi-layer structure. The second dielectric layer 372 may have a multi-layer structure. For example, the second dielectric layer 372 may have a structure in which first material layers 372a and second material layers 372b, which are different from each other, are stacked alternately. The thickness and number of material layers constituting the second dielectric layer 372 can be adjusted according to the center wavelength of the first filter 315. The second dielectric layer 372 may include three or more material layers that are different from each other.

[0122] The second filter 325 constituting the second filter array 320 may include two second metal reflective layers 151 and 152 spaced apart from each other, a second cavity 165 disposed between the second metal reflective layers 151 and 152, and a third dielectric layer 381 and a fourth dielectric layer 382 disposed below and above the second cavity 165, respectively.

[0123] The third dielectric layer 381 may be disposed below the second metal reflective layer 151, and the fourth dielectric layer 382 may be disposed above the second metal reflective layer 152. Similar to the first dielectric layer 371 and the second dielectric layer 372 described above, each of the third dielectric layer 381 and the fourth dielectric layer 382 may include, for example, titanium oxide, silicon nitride, hafnium oxide, silicon oxide, high refractive index polymers, etc.; however, this disclosure is not limited thereto.

[0124] The third dielectric layer 381 can have a single-layer or multi-layer structure. The fourth dielectric layer 382 can have a multi-layer structure. For example, the fourth dielectric layer 382 can have a structure in which first material layers 382a and second material layers 382b, which are different from each other, are stacked alternately. The thickness and number of material layers constituting the fourth dielectric layer 382 can be adjusted according to the center wavelength of the second filter 325. The fourth dielectric layer 382 may include three or more material layers that are different from each other.

[0125] FIG. 8 It shows FIG. 7 The transmission spectrum of the 1300 spectral filter. FIG. 8 It shows in FIG. 7 In the spectral filter 1300, the first filter array 310 includes seven filters with different center wavelengths and the second filter array 320 includes nine filters with different center wavelengths, representing the transmission spectrum.

[0126] The first metal reflective layers 131 and 132 may include Al, the second metal reflective layers 151 and 152 may include Cu, and the first cavity 145 and the second cavity 165 may include a multilayer film of TiO2 and SiN. Each of the first dielectric layer 371 and the third dielectric layer 381 may include SiN, and each of the second dielectric layer 372 and the fourth dielectric layer 382 may include a multilayer film of TiO2 and SiN. FIG. 8 In the diagram, "D1" represents the transmission spectrum of the first filter array 310, and "D2" represents the transmission spectrum of the second filter array 320. (Reference) FIG. 8 The 1300 spectral filter can achieve broadband characteristics and high transmittance.

[0127] FIG. 9 This is a schematic cross-sectional view of a spectral filter 1400 according to another example embodiment. For convenience, FIG. 9 The diagram illustrates a case where the first filter array 410 includes a filter (i.e., the first filter 415) and the second filter array 420 includes a filter (i.e., the second filter 425).

[0128] The first filter 415 constituting the first filter array 410 may include three first metal reflective layers 431, 432 and 433 spaced apart from each other, and two first cavities 441 and 442 disposed between the first metal reflective layers 431, 432 and 433.

[0129] The first metal reflective layers 431, 432, and 433 may include a first metal capable of reflecting light in a first wavelength region. The first cavities 441 and 442 may include dielectric materials such as silicon, silicon oxide, silicon nitride, hafnium oxide, titanium oxide, etc.

[0130] The second filter 425 constituting the second filter array 420 may include three second metal reflective layers 451, 452 and 453 spaced apart from each other, and two second cavities 461 and 462 disposed between the second metal reflective layers 451, 452 and 453.

[0131] The second metal reflective layers 451, 452, and 453 may include a second metal capable of reflecting light in a second wavelength region. The second cavities 461 and 462 may include dielectric materials such as silicon, silicon oxide, silicon nitride, hafnium oxide, titanium oxide, etc.

[0132] Although the foregoing embodiments describe a first filter 415 comprising two cavities (i.e., first cavities 441 and 442) and a second filter 425 comprising two cavities (i.e., second cavities 461 and 462), each of the first filter 415 and the second filter 425 may also comprise three or more cavities. Furthermore, although the foregoing embodiments describe a first filter 415 and the second filter 425 both having a multi-cavity structure, one of the first filter 415 and the second filter 425 may have a single-cavity structure, and the other may have a multi-cavity structure.

[0133] FIG. 10 This is a schematic cross-sectional view of a spectral filter 1500 according to another example embodiment. For convenience, FIG. 10 The diagram illustrates a case where the first filter array 510 includes a filter (i.e., the first filter 515) and the second filter array 520 includes a filter (i.e., the second filter 525).

[0134] refer to FIG. 10 The first filter 515 constituting the first filter array 510 may include three first metal reflective layers 431, 432, and 433 spaced apart from each other, two first cavities 441 and 442 disposed between the first metal reflective layers 431, 432, and 433, and a first dielectric layer 571 and a second dielectric layer 572 disposed below and above the first cavities 441 and 442, respectively. A description of the first metal reflective layers 431, 432, and 433 and the first cavities 441 and 442 has been provided above.

[0135] The first dielectric layer 571 may be disposed below the first metal reflective layer 431, and the second dielectric layer 572 may be disposed above the first metal reflective layer 433. The first dielectric layer 571 and the second dielectric layer 572 may improve transmittance and have a single-layer or multi-layer structure. Each of the first dielectric layer 571 and the second dielectric layer 572 may include, for example, titanium oxide, silicon nitride, hafnium oxide, silicon oxide, high refractive index polymers, etc., but this disclosure is not limited thereto.

[0136] The second filter 525 constituting the second filter array 520 may include three second metal reflective layers 451, 452, and 453 spaced apart from each other, two second cavities 461 and 462 disposed between the second metal reflective layers 451, 452, and 453, and a third dielectric layer 581 and a fourth dielectric layer 582 disposed below and above the second cavities 461 and 462, respectively. A description of the second metal reflective layers 451, 452, and 453 and the second cavities 461 and 462 has been provided above.

[0137] The third dielectric layer 581 may be disposed below the second metal reflective layer 451, and the fourth dielectric layer 582 may be disposed above the second metal reflective layer 453. The third dielectric layer 581 and the fourth dielectric layer 582 may have a single-layer or multi-layer structure, and may include, for example, titanium oxide, silicon nitride, hafnium oxide, silicon oxide, high refractive index polymers, etc., but this disclosure is not limited thereto.

[0138] FIG. 11 This is a schematic cross-sectional view of a spectral filter 1600 according to another example embodiment.

[0139] refer to FIG. 11 The first filter array 610 may include at least one filter having a center wavelength in a first wavelength region, and the second filter array 620 may include at least one filter having a center wavelength in a second wavelength region. FIG. 11 The diagram shows a first filter array 610 including a first filter 611, a second filter 612 and a third filter 613, and a second filter array 620 including a fourth filter 621, a fifth filter 622 and a sixth filter 623.

[0140] Each of the first to third filters 611, 612, and 613 constituting the first filter array 610 may include two first metallic reflective layers 631 and 632 spaced apart from each other, and a cavity (i.e., a first cavity 641, a second cavity 642, or a third cavity 643) disposed between the first metallic reflective layers 631 and 632. The description of the first metallic reflective layers 631 and 632 has been provided above and will not be repeated here.

[0141] The first to third filters 611, 612, and 613 may have different center wavelengths in the first wavelength region. For this purpose, the first filter 611, the second filter 612, and the third filter 613 may each include a first cavity 641, a second cavity 642, and a third cavity 643 with different effective refractive indices. Each of the first to third cavities 641, 642, and 643 may include a first material layer and at least one second material layer disposed in the first material layer and having a refractive index different from that of the first material layer.

[0142] FIG. 11 The illustration shows that each of the first to third cavities 641, 642 and 643 includes a first material layer and a plurality of second material layers arranged side by side in the first material layer and perpendicular to the first metal reflective layer 631. FIG. 11The illustration shows a second material layer with a mesa structure. However, this disclosure is not limited to this; the second material layer can be connected to the first metal reflective layers 631 and 632 disposed above and below it via, for example, an damascene process. Here, each of the first and second material layers can include, for example, silicon, silicon oxide, silicon nitride, titanium oxide, etc. In particular, the first material layer can include silicon oxide, and the second material layer can include titanium oxide.

[0143] The effective refractive index of the first to third cavities 641, 642 and 643 can be changed based on the width of the second material layer. FIG. 11 The diagram illustrates a second material layer with an increasing width from the first cavity 641 to the third cavity 643. In this case, among the first to third cavities 641, 642, and 643, the third cavity 643 can have the largest effective refractive index, while the first cavity 641 can have the smallest effective refractive index. Among the first to third filters 611, 612, and 613, the third filter 613 can have the longest center wavelength, while the first filter 611 can have the shortest center wavelength. Furthermore, depending on the cavity thickness or effective refractive index, some filters can have multiple center wavelengths.

[0144] The foregoing embodiments describe a situation where multiple second material layers are disposed perpendicular to the first metal reflective layer 631; however, this disclosure is not limited thereto, and multiple second material layers may be disposed parallel to the first metal reflective layer 631.

[0145] Each of the fourth to sixth filters 621, 622, and 623 constituting the second filter array 620 may include two second metallic reflective layers 651 and 652 spaced apart from each other, and a cavity (i.e., a fourth cavity 661, a fifth cavity 662, or a sixth cavity 663) disposed between the second metallic reflective layers 651 and 652. The description of the second metallic reflective layers 651 and 652 has been provided above and will not be repeated here.

[0146] The fourth to sixth filters 621, 622, and 623 may have different center wavelengths in the second wavelength region. For this purpose, the fourth filter 621, the fifth filter 622, and the sixth filter 623 may each include a fourth cavity 661, a fifth cavity 662, and a sixth cavity 663 with different effective refractive indices. Each of the fourth to sixth cavities 661, 662, and 663 may include a first material layer and at least one second material layer disposed in the first material layer and having a refractive index different from that of the first material layer.

[0147] FIG. 11The illustration shows each of the fourth to sixth cavities 661, 662, and 663 comprising a first material layer and a plurality of second material layers arranged side-by-side within the first material layer and perpendicular to the second metal reflective layer 651. Here, each of the first and second material layers may include, for example, silicon, silicon oxide, silicon nitride, titanium oxide, etc.

[0148] The effective refractive index of the fourth to sixth cavities 661, 662 and 663 can be changed based on the width of the second material layer. FIG. 11 The diagram illustrates a second material layer with an increasing width from the fourth cavity 661 to the sixth cavity 663. In this case, among the fourth to sixth cavities 661, 662, and 663, the sixth cavity 663 can have the largest effective refractive index, while the fourth cavity 661 can have the smallest effective refractive index. Among the fourth to sixth filters 621, 622, and 623, the sixth filter 623 can have the longest center wavelength, while the fourth filter 621 can have the shortest center wavelength. Furthermore, depending on the cavity thickness or effective refractive index, some filters can have multiple center wavelengths.

[0149] The foregoing embodiments describe a case where both the first filter array 610 and the second filter array 620 have a single-cavity structure. However, both the first filter array 610 and the second filter array 620 can have a multi-cavity structure. Furthermore, one of the first filter array 610 and the second filter array 620 can have a single-cavity structure, while the other can have a multi-cavity structure.

[0150] FIG. 12 This is a schematic cross-sectional view of a spectral filter 1700 according to another example embodiment. FIG. 12 The spectral filter 1700 can be used with FIG. 11 The spectral filter 1600 is the same, except that in the spectral filter 1700, the cavity also includes an etch stop layer.

[0151] The first filter 711, second filter 712, and third filter 713 constituting the first filter array 710 may each include a first cavity 741, a second cavity 742, and a third cavity 743 with different effective refractive indices. Here, each of the first to third cavities 741, 742, and 743 may include an etch stop layer 740a disposed on the first metal reflective layer 631, a first material layer disposed on the etch stop layer 740a, and at least one second material layer disposed in the first material layer. The etch stop layer 740a can facilitate a patterning process for forming the cavities. The etch stop layer 740a may include, for example, silicon oxide, titanium oxide, hafnium oxide, etc., but this disclosure is not limited thereto. The etch stop layer 740a may include a material with an etch rate two or more times (e.g., five or more times) lower than the etch rate of the dielectric material constituting the first to third cavities 741, 742, and 743. Specifically, when the first to third cavities 741, 742 and 743 comprise silicon oxide, the etch stop layer 740a may comprise hafnium oxide.

[0152] The fourth filter 721, fifth filter 722, and sixth filter 723 constituting the second filter array 720 may each include a fourth cavity 761, a fifth cavity 762, and a sixth cavity 763 with different effective refractive indices. Here, each of the fourth to sixth cavities 761, 762, and 763 may include an etch stop layer 760a disposed on the second metal reflective layer 651, a first material layer disposed on the etch stop layer 760a, and at least one second material layer disposed in the first material layer.

[0153] FIG. 13 This is a schematic cross-sectional view of a spectral filter 1800 according to another example embodiment. FIG. 13 The spectral filter 1800 can be used with FIG. 12 The spectral filter 1700 is the same as that of the spectral filter 1800, except that in the spectral filter 1800, the first dielectric layer 871 and the second dielectric layer 872 are respectively disposed at the lower part and the upper part of the first filter array 810, and the third dielectric layer 881 and the fourth dielectric layer 882 are respectively disposed at the lower part and the upper part of the second filter array 820.

[0154] refer to FIG. 13Each of the first filter 811, the second filter 812, and the third filter 813 constituting the first filter array 810 may include two first metal reflective layers 631 and 632 spaced apart from each other, a cavity (i.e., a first cavity 841, a second cavity 842, or a third cavity 843) disposed between the first metal reflective layers 631 and 632, and a first dielectric layer 871 and a second dielectric layer 872 disposed below and above the cavities 841, 842, or 843, respectively. The first filter 811, the second filter 812, and the third filter 813 may each include a first cavity 841, a second cavity 842, and a third cavity 843 with different effective refractive indices, such that the first filter to the third filter 811, 812, and 813 have different center wavelengths in a first wavelength region.

[0155] The first dielectric layer 871 can be disposed below the first metal reflective layer 631, and the second dielectric layer 872 can be disposed above the first metal reflective layer 632. The first dielectric layer 871 and the second dielectric layer 872 can improve the transmittance of the first filter to the third filter 811, 812 and 813.

[0156] Each of the first dielectric layer 871 and the second dielectric layer 872 may include a first material layer and at least one second material layer disposed in the first material layer and having a refractive index different from that of the first material layer. The first and second dielectric layers may include, for example, titanium oxide, silicon nitride, hafnium oxide, silicon oxide, high-refractive-index polymers, etc., but this disclosure is not limited thereto. The effective refractive index of the first dielectric layer 871 and the second dielectric layer 872 can be adjusted by changing the width of the second material layer according to the center wavelength of the first to third filters 811, 812, and 813. Each of the first dielectric layer 871 and the second dielectric layer 872 may also include an etch stop layer.

[0157] Each of the fourth filter 821, fifth filter 822, and sixth filter 823 constituting the second filter array 820 may include two second metal reflective layers 651 and 652 spaced apart from each other, a cavity (i.e., fourth cavity 861, fifth cavity 862, or sixth cavity 863) disposed between the second metal reflective layers 651 and 652, and a third dielectric layer 881 and a fourth dielectric layer 882 disposed below and above cavities 861, 862, or 863, respectively. The fourth filter 821, fifth filter 822, and sixth filter 823 may each include a fourth cavity 861, a fifth cavity 862, and a sixth cavity 863 with different effective refractive indices, such that the fourth to sixth filters 821, 822, and 823 have different center wavelengths in the second wavelength region.

[0158] A third dielectric layer 881 may be disposed below the second metal reflective layer 651, and a fourth dielectric layer 882 may be disposed above the second metal reflective layer 652. Each of the third dielectric layer 881 and the fourth dielectric layer 882 may include a first material layer and at least one second material layer disposed in the first material layer and having a refractive index different from that of the first material layer. The effective refractive index of the third dielectric layer 881 and the fourth dielectric layer 882 may be adjusted by changing the width of the second material layer according to the center wavelength of the fourth to sixth filters 821, 822 and 823. Each of the third dielectric layer 881 and the fourth dielectric layer 882 may also include an etch stop layer.

[0159] FIG. 14 This is a schematic cross-sectional view of a spectral filter 1900 according to another example embodiment.

[0160] refer to FIG. 14 The first filter array 910 may include at least one filter having a center wavelength in a first wavelength region, and the second filter array 920 may include at least one filter having a center wavelength in a second wavelength region. FIG. 14 The diagram shows a first filter array 910 including a first filter 911, a second filter 912 and a third filter 913, and a second filter array 920 including a fourth filter 921, a fifth filter 922 and a sixth filter 923.

[0161] The first wavelength region can be shorter than the second wavelength region. For example, the first wavelength region can range from approximately 250 nm to approximately 600 nm, and the second wavelength region can range from approximately 600 nm to approximately 1100 nm. However, this is just an example, and the first and second wavelength regions can vary depending on design considerations. Alternatively, the first wavelength region can be longer than the second wavelength region.

[0162] Each of the first to third filters 911, 912 and 913 constituting the first filter array 910 can transmit a specific center wavelength in the first wavelength region and has a Fabry-Perot structure, wherein a cavity (i.e., the first cavity 941, the second cavity 942 or the third cavity 943) is disposed between two metal reflective layers 931 and 932 spaced apart from each other.

[0163] When light passes through metal reflective layers 931 and 932 and is incident on cavities 941, 942, or 943, the light can be internally reflected within cavities 941, 942, or 943 between the metal reflective layers 931 and 932, during which constructive and destructive interference occur. Light with a specific center wavelength that satisfies the constructive interference condition can exit outside the filters (i.e., the first filter 911, the second filter 912, or the third filter 913). The wavelength and center wavelength of the light passing through filters 911, 912, or 913 can be determined based on the reflection bands of reflective layers 931 and 932 and the characteristics of cavities 941, 942, or 943.

[0164] Metal reflective layers 931 and 932 may include a specific metal capable of reflecting light in a first wavelength region. When the first wavelength region is shorter than the second wavelength region, metal reflective layers 931 and 932 may include, for example, Al, Ag, Au, Ti, W, TiN, etc. When the first wavelength region is longer than the second wavelength region, metal reflective layers 931 and 932 may include, for example, Cu, Ag, Au, TiN, Ti, W, etc. However, the above items are provided by way of example only. Metal reflective layers 931 and 932 may also include polycrystalline silicon. Metal reflective layers 931 and 932 may have a thickness of tens of nanometers; however, this disclosure is not limited thereto. For example, metal reflective layers 931 and 932 may have a thickness of about 10 nm to about 80 nm.

[0165] The first to third cavities 941, 942, and 943 disposed between the metal reflective layers 931 and 932 may comprise, for example, silicon, silicon oxide, silicon nitride, or titanium oxide; however, this disclosure is not limited thereto. The first to third filters 911, 912, and 913 may have different center wavelengths in the first wavelength region. For this purpose, the first filter 911, the second filter 912, and the third filter 913 may each comprise a first cavity 941, a second cavity 942, and a third cavity 943 with different thicknesses. Although not shown in the figures, since the first filter 911, the second filter 912, and the third filter 913 each comprise cavities with different effective refractive indices, the first to third filters 911, 912, and 913 may have different center wavelengths.

[0166] Each of the fourth to sixth filters 921, 922 and 923 constituting the second filter array 920 can transmit a specific center wavelength in the second wavelength region and has a Fabry-Perot structure, wherein a cavity (i.e., the fourth cavity 961, the fifth cavity 962 or the sixth cavity 963) is disposed between two Bragg reflector layers 951 and 952 spaced apart from each other.

[0167] When light passes through Bragg reflectors 951 and 952 and is incident on cavities 961, 962, or 963, the light can be internally reflected within cavities 961, 962, or 963 between Bragg reflectors 951 and 952, during which constructive and destructive interference occur. Light with a specific center wavelength and satisfying the constructive interference condition can exit outside the filters (i.e., the first filter 921, the second filter 922, or the third filter 923). The wavelength and center wavelength of the light passing through filters 921, 922, or 923 can be determined based on the reflection bands of Bragg reflectors 951 and 952 and the characteristics of cavities 961, 962, or 963.

[0168] Bragg reflector layers 951 and 952 can be distributed Bragg reflectors (DBRs). Bragg reflector layers 951 and 952 can have a structure in which at least one first material layer 951a and 952a with different refractive indices and at least one second material layer 951b and 952b are alternately stacked. The first material layer 951a and 952a or the second material layer 951b and 952b can comprise, for example, silicon oxide, titanium oxide, silicon nitride, or silicon. However, this is only an example.

[0169] When one of the first material layers 951a and 952a and the second material layers 951b and 952b constituting the Bragg reflector layers 951 and 952 includes a material (e.g., silicon) capable of absorbing light in the first wavelength region (e.g., short-wavelength light), light in the first wavelength region can be prevented from passing through the fourth filter to the sixth filter 921, 922 and 923.

[0170] The fourth to sixth cavities 961, 962 and 963 disposed between the Bragg reflector layers 951 and 952 may comprise, for example, silicon, silicon oxide, silicon nitride, hafnium oxide or titanium oxide; however, this disclosure is not limited thereto.

[0171] The fourth to sixth filters 921, 922, and 923 can have different center wavelengths in the second wavelength region. For this purpose, the fourth filter 921, the fifth filter 922, and the sixth filter 923 can each include a fourth cavity 961, a fifth cavity 962, and a sixth cavity 963 with different thicknesses. Although not shown in the figures, since the fourth filter 921, the fifth filter 922, and the sixth filter 923 each include cavities with different effective refractive indices, they can have different center wavelengths.

[0172] As described above, by arranging the first filter array 910 (where the first to third cavities 941, 942 and 943 are disposed between the metal reflective layers 931 and 932) and the second filter array 920 (where the fourth to sixth cavities 961, 962 and 963 are disposed between the Bragg reflective layers 951 and 952) on a plane, a spectral filter with broadband characteristics in the first wavelength region and the second wavelength region can be realized.

[0173] FIG. 15 This is a schematic cross-sectional view of a spectral filter 2000 according to another example embodiment. For convenience, FIG. 15 The diagram illustrates a case where the first filter array 1010 includes a filter (i.e., the first filter 1015) and the second filter array 1020 includes a filter (i.e., the second filter 1025).

[0174] refer to FIG. 15 The first filter 1015 constituting the first filter array 1010 may include two metal reflective layers 1031 and 1032 spaced apart from each other, and a first cavity 1045 disposed between the metal reflective layers 1031 and 1032. The metal reflective layers 1031 and 1032 and the first cavity 1045 have been described above.

[0175] The second filter 1025 constituting the second filter array 1020 may have a multi-cavity structure. Specifically, the second filter 1025 may include three Bragg reflector layers 1051, 1052, and 1053 spaced apart from each other, and two second cavities 1061 and 1062 disposed between the Bragg reflector layers 1051, 1052, and 1053. A description of the Bragg reflector layers 1051, 1052, and 1053 and the second cavities 1061 and 1062 has been provided above. The number of first and second material layers constituting each of the Bragg reflector layers 1051, 1052, and 1053 may vary. Although... FIG. 15 The illustration shows a second filter 1025 comprising two cavities (i.e., second cavities 1061 and 1062), but this disclosure is not limited thereto, and the second filter 1025 may include three or more cavities.

[0176] FIG. 16 It shows FIG. 15 The transmission spectrum of the 2000 spectral filter. FIG. 16 It shows in FIG. 15 In the spectral filter 2000, the first filter array 1010 includes four filters with different center wavelengths and the second filter array 1020 includes four filters with different center wavelengths, representing the transmission spectrum.

[0177] In the first filter array 1010, the metal reflective layers 1031 and 1032 comprise Al, and the first cavity 1045 comprises a multilayer of TiO2 and SiN. In the second filter array 1020, the Bragg reflective layers 1051, 1052, and 1053 comprise Si and SiO2, and the second cavities 1061 and 1062 comprise SiO2. FIG. 16 In the diagram, "S1" represents the transmission spectrum of the first filter array 1010, and "S2" represents the transmission spectrum of the second filter array 1020.

[0178] The foregoing embodiments illustrate a case where the first filter 1015 has a single-cavity structure and the second filter 1025 has a multi-cavity structure. However, the first filter 1015 can have a multi-cavity structure, and the second filter 1025 can have a single-cavity structure. Furthermore, both the first filter 1015 and the second filter 1025 can have a multi-cavity structure.

[0179] FIG. 17 This is a schematic cross-sectional view of a spectral filter 7100 according to another example embodiment.

[0180] refer to FIG. 17 The first filter array 1710 may include at least one filter having a center wavelength in a first wavelength region, and the second filter array 1720 may include at least one filter having a center wavelength in a second wavelength region. FIG. 17 The diagram shows a first filter array 1710 including a first filter 1711, a second filter 1712 and a third filter 1713, and a second filter array 1720 including a fourth filter 1721, a fifth filter 1722 and a sixth filter 1723.

[0181] The first wavelength region can be shorter than the second wavelength region. For example, the first wavelength region can range from approximately 250 nm to approximately 600 nm, and the second wavelength region can range from approximately 600 nm to approximately 1100 nm. However, this is just an example, and the first and second wavelength regions can vary depending on design considerations.

[0182] Each of the first to third filters 1711, 1712, and 1713 constituting the first filter array 1710 can transmit a specific center wavelength in a first wavelength region and has a Fabry-Perot structure, wherein a cavity (i.e., a first cavity 1141, a second cavity 1142, or a third cavity 1143) is disposed between two first metallic reflective layers 1131 and 1132 spaced apart from each other. The wavelength and center wavelength of light passing through the filter (i.e., the first filter 1711, the second filter 1712, or the third filter 1713) can be determined based on the reflection bands of the first metallic reflective layers 1131 and 1132 and the characteristics of the cavities 1141, 1142, or 1143.

[0183] The first metal reflective layers 1131 and 1132 may include a specific metal capable of reflecting light in a first wavelength region. When the first wavelength region is a short wavelength region and the second wavelength region is a long wavelength region, the first metal reflective layers 1131 and 1132 may include, for example, Al, Ag, Au, Ti, W, TiN, etc. However, the above items are provided by way of example only. The first metal reflective layers 1131 and 1132 may have a thickness of tens of nanometers; however, this disclosure is not limited thereto. For example, the first metal reflective layers 1131 and 1132 may have a thickness of about 10 nm to about 80 nm.

[0184] The first to third cavities 1141, 1142, and 1143 disposed between the first metal reflective layers 1131 and 1132 may comprise, for example, silicon, silicon oxide, silicon nitride, or titanium oxide; however, this disclosure is not limited thereto. The first to third filters 1711, 1712, and 1713 may have different center wavelengths in the first wavelength region. Therefore, the first filter 1711, the second filter 1712, and the third filter 1713 may each comprise a first cavity 1141, a second cavity 1142, and a third cavity 1143 with different thicknesses.

[0185] The first dielectric layer 1171 may be further disposed below each of the first to third cavities 1141, 1142, and 1143, and the second dielectric layer 1172 may be further disposed above the first to third cavities 1141, 1142, and 1143. The first dielectric layer 1171 and the second dielectric layer 1172 may improve the transmittance of the first to third filters 1711, 1712, and 1713. The first dielectric layer 1171 and the second dielectric layer 1172 may have a single-layer structure or a multi-layer structure. Each of the first dielectric layer 1171 and the second dielectric layer 1172 may include, for example, titanium oxide, silicon nitride, hafnium oxide, silicon oxide, high refractive index polymers, etc. However, the foregoing is provided by way of example only.

[0186] The thicknesses of the first dielectric layer 1171 and the second dielectric layer 1172 can vary according to the center wavelengths of the first filter to the third filter 1711, 1712 and 1713. FIG. 17 The thickness of the first dielectric layer 1171 and the second dielectric layer 1172 is shown to increase with the center wavelength of the first to the third filters 1711, 1712 and 1713. The thickness of each of the first dielectric layer 1171 and the second dielectric layer 1172 may be from about 10 nm to 20,000 nm; however, this disclosure is not limited thereto.

[0187] Each of the fourth to sixth filters 1721, 1722, and 1723 constituting the second filter array 1720 can transmit a specific center wavelength in the second wavelength region and has a Fabry-Perot structure, wherein cavities (i.e., the fourth cavity 1161, the fifth cavity 1162, and the sixth cavity 1163) are disposed between a second metallic reflective layer 1151 and a Bragg reflective layer 1152 spaced apart from each other. The second metallic reflective layer 1151 may be disposed below the fourth to sixth cavities 1161, 1162, and 1163, and the Bragg reflective layer 1152 may be disposed above the fourth to sixth cavities 1161, 1162, and 1163. The wavelength and center wavelength of light passing through the filters (i.e., the fourth filter 1721, the fifth filter 1722, or the sixth filter 1723) can be determined based on the reflection bands of the second metallic reflective layer 1151 and the Bragg reflective layer 1152 and the characteristics of cavities 1161, 1162, or 1163.

[0188] When the first wavelength region is a short wavelength region and the second wavelength region is a long wavelength region, the second metal reflective layer 1151 may include, for example, Cu, Ag, Au, Ti, W, TiN, etc. However, the foregoing is provided by way of example only. The second metal reflective layer 1151 may also include polycrystalline silicon. The thickness of the second metal reflective layer 1151 may be tens of nanometers; however, this disclosure is not limited thereto. For example, the second metal reflective layer 1151 may have a thickness of about 10 nm to about 80 nm.

[0189] The Bragg reflector layer 1152 may be a DBR (Dielectric-Reflective Brush). The Bragg reflector layer 1152 may have a structure in which at least one first material layer 1152a and at least one second material layer 1152b with different refractive indices are alternately stacked. The first material layer 1152a or the second material layer 1152b may comprise, for example, silicon oxide, titanium oxide, silicon nitride, or silicon. However, this is only an example. In particular, the first material layer 1152a may comprise silicon oxide, and the second material layer 1152b may comprise silicon.

[0190] When one of the first material layer 1152a and the second material layer 1152b constituting the Bragg reflector layer 1152 includes a material (e.g., silicon) capable of absorbing light in the first wavelength region (e.g., short-wavelength light), light in the first wavelength region can be prevented from passing through the fourth filter to the sixth filter 1721, 1722 and 1723.

[0191] The fourth to sixth cavities 1161, 1162 and 1163 disposed between the second metal reflective layer 1151 and the Bragg reflective layer 1152 may comprise, for example, silicon, silicon oxide, silicon nitride, hafnium oxide or titanium oxide; however, this disclosure is not limited thereto.

[0192] The fourth to sixth filters 1721, 1722 and 1723 can have different center wavelengths in the second wavelength region. For this purpose, the fourth filter 1721, the fifth filter 1722 and the sixth filter 1723 can respectively include a fourth cavity 1161, a fifth cavity 1162 and a sixth cavity 1163 with different thicknesses.

[0193] The third dielectric layer 1181 may be further disposed below the second metallic reflective layer 1151, and the fourth dielectric layer 1182 may be further disposed above the Bragg reflective layer 1152. The third dielectric layer 1181 and the fourth dielectric layer 1182 can improve the transmittance of the fourth to sixth filters 1721, 1722 and 1723. The third dielectric layer 1181 and the fourth dielectric layer 1182 may have a single-layer structure or a multi-layer structure. Similar to the first dielectric layer 1171 and the second dielectric layer 1172 described above, each of the third dielectric layer 1181 and the fourth dielectric layer 1182 may include, for example, titanium oxide, silicon nitride, hafnium oxide, silicon oxide, high refractive index polymers, etc.; however, this disclosure is not limited thereto.

[0194] The thicknesses of the third dielectric layer 1181 and the fourth dielectric layer 1182 can vary according to the center wavelengths of the fourth to sixth filters 1721, 1722 and 1723. FIG. 17 The thickness of the third dielectric layer 1181 and the fourth dielectric layer 1182 is shown to increase with the center wavelength of the fourth to sixth filters 1721, 1722 and 1723. The thickness of each of the third dielectric layer 1181 and the fourth dielectric layer 1182 may be from about 10 nm to 20,000 nm; however, this disclosure is not limited thereto.

[0195] According to the embodiment, since the fourth to sixth filters 1721, 1722 and 1723 constituting the second filter array 1720 have a structure in which the fourth to sixth cavities 1161, 1162 and 1163 are disposed between the second metal reflective layer 1151 and the Bragg reflective layer 1152, the transmittance of light in the second wavelength region can be further improved.

[0196] FIG. 18A A filter structure (“Cu-Cu structure”) including Cu metal layers below and above cavity 1160 is shown. FIG. 18B It shows FIG. 18A The transmission spectrum of the Cu-Cu structure. FIG. 18A In the middle, the lower dielectric layer includes a SiN / SiO2 multilayer, and the upper dielectric layer includes a TiO2 layer. In addition, cavity 1160 includes a SiN layer.

[0197] FIG. 19A This illustrates a filter structure (“Si / SiO2 DBR-Si / SiO2 DBR structure”) including Si / SiO2 Bragg reflector layers below and above cavity 1160. FIG. 19B It shows FIG. 19A Transmission spectra of Si / SiO2 DBR-Si / SiO2 DBR structures. FIG. 19A In the middle, the lower dielectric layer includes a SiN / SiO2 multilayer, and the upper dielectric layer includes a SiO2 layer. In addition, cavity 1160 includes a SiN layer.

[0198] FIG. 20A The filter structure shown includes a Cu metal reflective layer below cavity 1160 and a Si / SiO2 DBR layer above cavity 1160 (“Cu-Si / SiO2 DBR structure”). FIG. 20B It shows FIG. 20A Transmission spectra of Cu-Si / SiO2 DBR structures.

[0199] exist FIG. 20A In the middle, the lower dielectric layer includes a SiN / SiO2 multilayer, and the upper dielectric layer includes a SiO2 layer. In addition, cavity 1160 includes a SiN layer. FIG. 18A , FIG. 19A and FIG. 20A The filter structure shown can have a center wavelength of approximately 930 nm.

[0200] refer to FIG. 18B , FIG. 19B and FIG. 20B ,and FIG. 18A Compared to the Cu-Cu structure, FIG. 20A The Cu-Si / SiO2 DBR structure can exhibit improved transmittance. Furthermore, similar to... FIG. 18AThe Cu-Cu structure, and FIG. 19A Compared to the Si / SiO2 DBR-Si / SiO2 DBR structure, FIG. 20A The Cu-Si / SiO2 DBR structure can have a constant full width at half maximum (FWHM) of the transmission peak.

[0201] The foregoing embodiments describe a case where both the first filter array 1710 and the second filter array 1720 have a single-cavity structure. However, both the first filter array 1710 and the second filter array 1720 can have a multi-cavity structure. Furthermore, one of the first filter array 1710 and the second filter array 1720 can have a single-cavity structure, while the other can have a multi-cavity structure.

[0202] FIG. 21 This is a schematic cross-sectional view of a spectral filter 7200 according to another example embodiment.

[0203] refer to FIG. 21 The first filter array 2710 may include at least one filter having a center wavelength in a first wavelength region, and the second filter array 2720 may include at least one filter having a center wavelength in a second wavelength region. FIG. 21 The diagram shows a first filter array 2710 including a first filter 2711, a second filter 2712 and a third filter 2713, and a second filter array 2720 including a fourth filter 2721, a fifth filter 2722 and a sixth filter 2723.

[0204] Each of the first to third filters 2711, 2712, and 2713 can have a Fabry-Perot structure, wherein a cavity (i.e., a first cavity 2141, a second cavity 2142, or a third cavity 2143) is disposed between two first metallic reflective layers 2131 and 2132 spaced apart from each other. The first metallic reflective layers 2131 and 2132 and the first to third cavities 2141, 2142, and 2143 are referenced above. FIG. 17 Therefore, any redundant descriptions of it are omitted.

[0205] The first dielectric layer 2171 may be further disposed below each of the first to third cavities 2141, 2142, and 2143, and the second dielectric layer 2172 may be further disposed above the first to third cavities 2141, 2142, and 2143. The first dielectric layer 2171 and the second dielectric layer 2172 may improve the transmittance of the first to third filters 2711, 2712, and 2713.

[0206] The first dielectric layer 2171 may include a first material layer and at least one second material layer disposed in the first material layer and having a refractive index different from that of the first material layer. The first and second material layers may include, for example, titanium oxide, silicon nitride, hafnium oxide, silicon oxide, high-refractive-index polymers, etc., but this disclosure is not limited thereto. The effective refractive index of the first dielectric layer 2171 can be adjusted by changing the width of the second material layer according to the center wavelength of the first to third filters 2711, 2712, and 2713. Here, the first dielectric layer 2171 may also include an etch stop layer.

[0207] The second dielectric layer 2172 disposed above each of the first to third cavities 2141, 2142 and 2143 can be referenced as above. FIG. 17 As described. That is, the thickness of the second dielectric layer 2172 can vary according to the center wavelength of the first to the third filters 2711, 2712 and 2713. FIG. 21 The thickness of the second dielectric layer 2172 is shown to increase with the center wavelength of the first to the third filters 2711, 2712 and 2713.

[0208] Although not shown in the figure, the second dielectric layer 2172 may have a structure similar to that of the first dielectric layer 2171. In this case, the second dielectric layer 2172 may include a first material layer and at least one second material layer disposed within the first material layer and having a refractive index different from that of the first material layer. The effective refractive index of the second dielectric layer 2172 can be adjusted by changing the width of the second material layer according to the center wavelength of the first to third filters 2711, 2712, and 2713.

[0209] Each of the fourth to sixth filters 2721, 2722, and 2723 may have a Fabry-Perot structure, wherein cavities (i.e., the fourth cavity 2161, the fifth cavity 2162, or the sixth cavity 2163) are disposed between a second metallic reflective layer 2151 and a Bragg reflective layer 2152 spaced apart from each other. The Bragg reflective layer 2152 may have a structure in which at least one first material layer 2152a and at least one second material layer 2152b with different refractive indices are alternately stacked. The second metallic reflective layer 2151, the fourth to sixth cavities 2161, 2162, and 2163, and the Bragg reflective layer 2152 are as described above. FIG. 17 Therefore, any redundant descriptions of it are omitted.

[0210] The third dielectric layer 2181 may be further disposed below the second metallic reflective layer 2151, and the fourth dielectric layer 2182 may be further disposed above the Bragg reflective layer 2152. The third dielectric layer 2181 and the fourth dielectric layer 2182 can improve the transmittance of the fourth to sixth filters 2721, 2722 and 2723.

[0211] The third dielectric layer 2181 may include a first material layer and at least one second material layer disposed in the first material layer and having a refractive index different from that of the first material layer. The first and second material layers may include, for example, titanium oxide, silicon nitride, hafnium oxide, silicon oxide, high-refractive-index polymers, etc., but this disclosure is not limited thereto. The effective refractive index of the third dielectric layer 2181 can be adjusted by changing the width of the second material layer according to the center wavelength of the fourth to sixth filters 2721, 2722, and 2723. Here, the third dielectric layer 2181 may also include an etch stop layer.

[0212] The fourth dielectric layer 2182 disposed above each of the fourth to sixth cavities 2161, 2162 and 2163 can be referenced as above. FIG. 17 As described. That is, the thickness of the fourth dielectric layer 2182 can vary according to the center wavelength of the fourth to sixth filters 2721, 2722 and 2723. FIG. 21 The thickness of the fourth dielectric layer 2182 is shown to increase with the center wavelength of the fourth to sixth filters 2721, 2722 and 2723.

[0213] Although not shown in the figure, the fourth dielectric layer 2182 may have a structure similar to that of the third dielectric layer 2181. In this case, the fourth dielectric layer 2182 may include a first material layer and at least one second material layer disposed in the first material layer and having a refractive index different from that of the first material layer. The effective refractive index of the fourth dielectric layer 2182 can be adjusted by changing the width of the second material layer according to the center wavelength of the fourth to sixth filters 2721, 2722 and 2723.

[0214] FIG. 22 This is a schematic cross-sectional view of a spectral filter 7300 according to another example embodiment.

[0215] refer to FIG. 22 The first filter array 3710 may include at least one filter having a center wavelength in a first wavelength region, and the second filter array 3720 may include at least one filter having a center wavelength in a second wavelength region. FIG. 22The diagram illustrates a first filter array 3710 comprising a first filter 3711, a second filter 3712, and a third filter 3713, and a second filter array 3720 comprising a fourth filter 3721, a fifth filter 3722, and a sixth filter 3723.

[0216] Each of the first to third filters 3711, 3712, and 3713 can have a Fabry-Perot structure, wherein a cavity (i.e., the first cavity 3141, the second cavity 3142, or the third cavity 3143) is disposed between two first metallic reflective layers 3131 and 3132 spaced apart from each other. As the first metallic reflective layers 3131 and 3132 are referenced above... FIG. 17 Therefore, any redundant descriptions of it are omitted.

[0217] The first filter 3711, the second filter 3712, and the third filter 3713 may each include a first cavity 3141, a second cavity 3142, and a third cavity 3143 with different effective refractive indices. Each of the first to third cavities 3141, 3142, and 3143 may include a first material layer and at least one second material layer disposed in the first material layer and having a refractive index different from that of the first material layer. Here, each of the first to third cavities 3141, 3142, and 3143 may also include an etch stop layer.

[0218] FIG. 22 The illustration shows each of the first to third cavities 3141, 3142, and 3143 comprising a first material layer and a plurality of second material layers disposed side-by-side within the first material layer. Here, each of the first and second material layers may include, for example, silicon, silicon oxide, silicon nitride, titanium oxide, etc. Specifically, the first material layer may include silicon oxide, and the second material layer may include titanium oxide.

[0219] The effective refractive index of the first to third cavities 3141, 3142, and 3143 can be varied based on the width of the second material layer. For example, among the first to third cavities 3141, 3142, and 3143, the third cavity 3143 can have the largest effective refractive index, while the first cavity 3141 can have the smallest effective refractive index. In this case, among the first to third filters 3711, 3712, and 3713, the third filter 3713 can have the longest center wavelength, while the first filter 3711 can have the shortest center wavelength.

[0220] The first dielectric layer 3171 may be further disposed below each of the first to third cavities 3141, 3142, and 3143, and the second dielectric layer 3172 may be further disposed above the first to third cavities 3141, 3142, and 3143. As described above, the first dielectric layer 3171 and the second dielectric layer 3172... FIG. 17 Therefore, any redundant description thereof is omitted. Meanwhile, the first dielectric layer 3171 and / or the second dielectric layer 3172 may have the same... FIG. 21 The first dielectric layer is similar to the structure of 2171.

[0221] Each of the fourth to sixth filters 3721, 3722, and 3723 may have a Fabry-Perot structure, wherein a cavity (i.e., the fourth cavity 3161, the fifth cavity 3162, or the sixth cavity 3163) is disposed between a second metallic reflective layer 3151 and a Bragg reflective layer 3152 spaced apart from each other. The Bragg reflective layer 3152 may have a structure in which at least one first material layer 3152a and at least one second material layer 3152b with different refractive indices are alternately stacked. As the second metallic reflective layer 3151 and the Bragg reflective layer 3152 are referenced above... FIG. 17 Therefore, any redundant descriptions of it are omitted.

[0222] The fourth filter 3721, the fifth filter 3722, and the sixth filter 3723 may each include a fourth cavity 3161, a fifth cavity 3162, and a sixth cavity 3163 having different effective refractive indices. Each of the fourth to sixth cavities 3161, 3162, and 3163 may include a first material layer and at least one second material layer disposed in the first material layer and having a refractive index different from that of the first material layer.

[0223] FIG. 22 The illustration shows each of the fourth to sixth cavities 3161, 3162, and 3163 comprising a first material layer and a plurality of second material layers disposed side-by-side within the first material layer. Here, each of the first and second material layers may include, for example, silicon, silicon oxide, silicon nitride, titanium oxide, etc. Specifically, the first material layer may include silicon oxide, and the second material layer may include titanium oxide.

[0224] The effective refractive index of cavities 3161, 3162, and 3163 can be varied based on the width of the second material layer. For example, among cavities 3161, 3162, and 3163, cavity 3163 can have the largest effective refractive index, while cavity 3161 can have the smallest effective refractive index. In this case, among filters 3721, 3722, and 3723, filter 3723 can have the longest center wavelength, while filter 3721 can have the shortest center wavelength.

[0225] The third dielectric layer 3181 may be further disposed below each of the fourth to sixth cavities 3161, 3162, and 3163, and the fourth dielectric layer 3182 may be further disposed above the fourth to sixth cavities 3161, 3162, and 3163. As the third dielectric layer 3181 and the fourth dielectric layer 3182 are as described above... FIG. 17 Therefore, any redundant description thereof is omitted. Meanwhile, the third dielectric layer 3181 and / or the fourth dielectric layer 3182 may have the same... FIG. 21 The third dielectric layer is similar to the structure of 2181.

[0226] FIG. 23 This is a schematic cross-sectional view of a spectral filter 7400 according to another example embodiment.

[0227] refer to FIG. 23 The first filter array 4710 may include at least one filter having a center wavelength in a first wavelength region, and the second filter array 4720 may include at least one filter having a center wavelength in a second wavelength region. FIG. 23 The diagram illustrates a first filter array 4710 comprising a first filter 4711, a second filter 4712, and a third filter 4713, and a second filter array 4720 comprising a fourth filter 4721, a fifth filter 4722, and a sixth filter 4723.

[0228] Each of the first to third filters 4711, 4712, and 4713 may have a Fabry-Perot structure, wherein a cavity (i.e., a first cavity 4141, a second cavity 4142, or a third cavity 4143) is disposed between two first metallic reflective layers 4131 and 4132 spaced apart from each other. A first dielectric layer 4171 and a second dielectric layer 4172 may be further disposed below and above the first to third cavities 4141, 4142, and 4143, respectively. The first metallic reflective layers 4131 and 4132, the first to third cavities 4141, 4142, and 4143, and the first dielectric layer 4171 and the second dielectric layer 4172 are as described above. FIG. 17Therefore, any redundant description of it is omitted. Meanwhile, the first to third cavities 4141, 4142, and 4143 can have the same... FIG. 22 The first to third cavities 3141, 3142 and 3143 have similar structures, and the first dielectric layer 4171 and / or the second dielectric layer 4172 may have the same structure as the first to third cavities 3141, 3142 and 3143. FIG. 21 The first dielectric layer is similar to the structure of 2171.

[0229] Each of the fourth to sixth filters 4721, 4722, and 4723 may have a Fabry-Perot structure, wherein a cavity (i.e., the fourth cavity 4161, the fifth cavity 4162, or the sixth cavity 4163) is disposed between a Bragg reflective layer 4151 and a second metallic reflective layer 4152 spaced apart from each other. A third dielectric layer 4181 and a fourth dielectric layer 4182 may be further disposed below and above the fourth to sixth cavities 4161, 4162, and 4163, respectively. The fourth to sixth cavities 4161, 4162, and 4163, as well as the third dielectric layer 4181 and the fourth dielectric layer 4182, are referenced above. FIG. 17 Therefore, any redundant description of it is omitted. Meanwhile, the fourth to sixth cavities 4161, 4162, and 4163 can have the same... FIG. 22 The fourth to sixth cavities 3161, 3162 and 3163 have similar structures, and the third dielectric layer 4181 and / or the fourth dielectric layer 4182 may have the same structure as the fourth dielectric layer 3161, 3162 and 3163. FIG. 21 The third dielectric layer is similar to the structure of 2181.

[0230] A Bragg reflector layer 4151 may be disposed beneath the fourth to sixth cavities 4161, 4162, and 4163. The Bragg reflector layer 4151 may be a DBR (Dielectric-Reflective Bragg Blend). The Bragg reflector layer 4151 may have a structure in which at least one first material layer 4151a and at least one second material layer 4151b with different refractive indices are alternately stacked. The first material layer 4151a or the second material layer 4151b may comprise, for example, silicon oxide, titanium oxide, silicon nitride, or silicon. However, this is only an example. In particular, the first material layer 4151a may comprise silicon oxide, and the second material layer 4151b may comprise silicon.

[0231] When one of the first material layer 4151a and the second material layer 4151b constituting the Bragg reflector layer 4151 includes a material (e.g., silicon) capable of absorbing light in the first wavelength region (e.g., short-wavelength light), light in the first wavelength region can be prevented from passing through the fourth filter to the sixth filter 4721, 4722 and 4723.

[0232] The second metal reflective layer 4152 may be disposed above the fourth to sixth cavities 4161, 4162, and 4163. When the first wavelength region is a short wavelength region and the second wavelength region is a long wavelength region, the second metal reflective layer 4152 may include, for example, Cu, Ag, Au, Ti, W, TiN, etc.; however, this disclosure is not limited thereto. The second metal reflective layer 4152 may also include polycrystalline silicon.

[0233] FIG. 24 This is a schematic cross-sectional view of a spectral filter 7500 according to another example embodiment.

[0234] refer to FIG. 24 The first filter array 5710 may include at least one filter having a center wavelength in a first wavelength region, and the second filter array 5720 may include at least one filter having a center wavelength in a second wavelength region. FIG. 24 The diagram shows a first filter array 5710 including a first filter 5711, a second filter 5712 and a third filter 5713, and a second filter array 5720 including a fourth filter 5721, a fifth filter 5722 and a sixth filter 5723.

[0235] Each of the first to third filters 5711, 5712, and 5713 may have a Fabry-Perot structure, wherein a cavity (i.e., the first cavity 5141, the second cavity 5142, or the third cavity 5143) is disposed between the first metallic reflective layer 5131 and the first Bragg reflective layer 5132. Each of the fourth to sixth filters 5721, 5722, and 5723 may have a Fabry-Perot structure, wherein a fourth cavity 5161, a fifth cavity 5162, or a sixth cavity 5163 is disposed between the second metallic reflective layer 5151 and the second Bragg reflective layer 5152.

[0236] When the first wavelength region is a short wavelength region and the second wavelength region is a long wavelength region, the first metal reflective layer 5131 may include, for example, Al, Ag, Au, Ti, W, TiN, etc., and the second metal reflective layer 5151 may include, for example, Cu, Ag, Au, Ti, W, TiN, etc. The second metal reflective layer 5151 may also include polycrystalline silicon.

[0237] Each of the first Bragg reflector layer 5132 and the second Bragg reflector layer 5152 may have the following structure: at least one first material layer 5132a or 5152a with different refractive indices and at least one second material layer 5132b or 5152b are stacked alternately. The first material layers 5132a and 5152a or the second material layers 5132b and 5152b may comprise, for example, silicon oxide, titanium oxide, silicon nitride, or silicon. However, this is only an example.

[0238] The first to third cavities 5141, 5142, and 5143 can have different thicknesses. Furthermore, the first to third cavities 5141, 5142, and 5143 can be as follows: FIG. 22 The fourth to sixth cavities 5161, 5162, and 5163 have different effective refractive indices. Furthermore, the fourth to sixth cavities 5161, 5162, and 5163 can be as follows: FIG. 22 The figures show different effective refractive indices.

[0239] The first dielectric layer 5171 and the second dielectric layer 5172 may be further disposed below and above the first to third cavities 5141, 5142, and 5143, respectively. The first dielectric layer 5171 and the second dielectric layer 5172 are as described above. FIG. 17 As described above. Simultaneously, the first dielectric layer 5171 and / or the second dielectric layer 5172 may have the same... FIG. 21 The first dielectric layer is similar to the structure of 2171.

[0240] The third dielectric layer 5181 and the fourth dielectric layer 5182 can be further disposed below and above the fourth to sixth cavities 5161, 5162, and 5163, respectively. The third dielectric layer 5181 and the fourth dielectric layer 5182 are referenced above. FIG. 17 As described above. Simultaneously, the third dielectric layer 5181 and / or the fourth dielectric layer 5182 may have the same... FIG. 21 The third dielectric layer is similar to the structure of 2181.

[0241] The foregoing embodiments illustrate a configuration where the first metal reflective layer 5131 and the first Bragg reflective layer 5132 are respectively disposed below and above the first to third cavities 5141, 5142, and 5143, and the second metal reflective layer 5151 and the second Bragg reflective layer 5152 are respectively disposed below and above the fourth to sixth cavities 5161, 5162, and 5163. However, this disclosure is not limited thereto; the first Bragg reflective layer 5132 and the first metal reflective layer 5131 may be disposed below and above the first to third cavities 5141, 5142, and 5143, and the second Bragg reflective layer 5152 and the second metal reflective layer 5151 may be disposed below and above the fourth to sixth cavities 5161, 5162, and 5163, respectively.

[0242] FIG. 25 This is a schematic cross-sectional view of a spectral filter 2100 according to another example embodiment.

[0243] Reference FIG. 25The spectral filter 2100 may include a first filter array 1110, a second filter array 1120, and a microlens array 1150 disposed on the first filter array 1110 and the second filter array 1120. The first filter array 1110 may include a first filter 1111, a second filter 1112, and a third filter 1113 having a center wavelength in a first wavelength region, and the second filter array 1120 may include a fourth filter 1121, a fifth filter 1122, and a sixth filter 1123 having a center wavelength in a second wavelength region.

[0244] The first filter array 1110 can be any one of the first filter arrays 110 to 1010 and 1710 to 5710 described above, and the second filter array 1120 can be any one of the second filter arrays 120 to 1020 and 1720 to 5720 described above. Descriptions of the first filter array 1110 and the second filter array 1120 are omitted.

[0245] A microlens array 1150, comprising multiple microlenses 1150a, may be disposed above a first filter array 1110 and a second filter array 1120. The microlenses 1150a may be used to focus external light onto corresponding filters among the first to sixth filters 1111, 1112, 1113, 1121, 1122 and 1123.

[0246] FIG. 25 The illustration shows a microlens 1150a configured to correspond one-to-one with the first to sixth filters 1111, 1112, 1113, 1121, 1122, and 1123. However, this is merely exemplary, and multiple filters among the first to sixth filters 1111, 1112, 1113, 1121, 1122, and 1123 may be configured to correspond to a single microlens 1150a.

[0247] FIG. 26 This is a schematic cross-sectional view of a spectral filter 2200 according to another example embodiment.

[0248] refer to FIG. 26 The spectral filter 2200 may include a first filter array 1210, a second filter array 1220, and a color filter array 1230. The first filter array 1210, the second filter array 1220, and the color filter array 1230 may be arranged on substantially the same plane.

[0249] The first filter array 1210 may include a first filter 1211, a second filter 1212, and a third filter 1213 having a center wavelength in a first wavelength region, and the second filter array 1220 may include a fourth filter 1221, a fifth filter 1222, and a sixth filter 1223 having a center wavelength in a second wavelength region. The first filter array 1210 may be any one of the first filter arrays 110 to 1010 and 1710 to 5710 described above, and the second filter array 1220 may be any one of the second filter arrays 120 to 1020 and 1720 to 5720 described above. Descriptions of the first filter array 1210 and the second filter array 1220 are omitted.

[0250] The color filter array 1230 may include, for example, a red color filter 1231, a green color filter 1232, and a blue color filter 1233. The red color filter 1231 can transmit red light with a wavelength of approximately 600 nm to approximately 700 nm, the green color filter 1232 can transmit green light with a wavelength of approximately 500 nm to approximately 600 nm, and the blue color filter 1233 can transmit blue light with a wavelength of approximately 400 nm to approximately 500 nm. For example, typical color filters used in color display devices such as liquid crystal display devices and organic light-emitting display devices can be used as the red color filter 1231, green color filter 1232, and blue color filter 1233. A microlens array 1250 including multiple microlenses 1250a may be further disposed above the first filter array 1210, the second filter array 1220, and the color filter array 1230.

[0251] According to the embodiment, information about the center wavelengths of the first to sixth filters 1211, 1212, 1213, 1221, 1222 and 1223 can be obtained not only by using the first filter array 1210 and the second filter array 1220, but also by using the color filter array 1230 to obtain information about the wavelengths of red, green and blue light.

[0252] FIG. 27 This is a schematic cross-sectional view of a spectral filter 2300 according to another example embodiment.

[0253] refer to FIG. 27The spectral filter 2300 may include a first filter array 1310, a second filter array 1320, and an additional filter array 2500 disposed on the first filter array 1310 and the second filter array 1320. The first filter array 1310 may include a first filter 1311, a second filter 1312, and a third filter 1313 having a center wavelength in a first wavelength region, and the second filter array 1320 may include a fourth filter 1321, a fifth filter 1322, and a sixth filter 1323 having a center wavelength in a second wavelength region.

[0254] The first filter array 1310 can be any one of the first filter arrays 110 to 1010 and 1710 to 5710 described above, and the second filter array 1320 can be any one of the second filter arrays 120 to 1020 and 1720 to 5720 described above. Descriptions of the first filter array 1310 and the second filter array 1320 are omitted.

[0255] The additional filter array 2500 may include multiple additional filters (i.e., a first additional filter 2501, a second additional filter 2502, and a third additional filter 2503). FIG. 27 The illustration shows a first additional filter 2501 configured to correspond to the first filter 1311 and the second filter 1312, a second additional filter 2502 configured to correspond to the third filter 1313 and the fourth filter 1321, and a third additional filter 2503 configured to correspond to the fifth filter 1322 and the sixth filter 1323. However, this is merely exemplary, and each of the first to third additional filters 2501, 2502, and 2503 may be configured to correspond to one or more of the first to sixth filters 1311, 1312, 1313, 1321, 1322, and 1323.

[0256] Each of the first to third supplementary filters 2501, 2502, and 2503 can block light in a wavelength band that is substantially impenetrable by the corresponding filters 1311, 1312, 1313, 1321, 1322, and 1323. For example, when the first filter 1311 and the second filter 1312 have a center wavelength in the band of approximately 400 nm to approximately 500 nm, the first supplementary filter 2501 can be a blue filter that transmits blue light. Furthermore, when the third filter 1313 and the fourth filter 1321 have a center wavelength in the band of approximately 500 nm to approximately 600 nm, the second supplementary filter 2502 can be a green filter that transmits green light. When the fifth filter 1322 and the sixth filter 1323 have a center wavelength in the band of approximately 600 nm to approximately 700 nm, the third additional filter 2503 can be a red filter that transmits red light.

[0257] The additional filter array 2500 can be a color filter array. In this case, the first to third additional filters 2501, 2502, and 2503 can be a blue color filter, a green color filter, and a red color filter, respectively. For example, typical color filters used in color display devices such as liquid crystal display devices and organic light-emitting display devices can be used as blue, green, and red color filters.

[0258] The additional filter array 2500 can be a broadband filter array. In this case, the first to third additional filters 2501, 2502, and 2503 can respectively include a first broadband filter, a second broadband filter, and a third broadband filter. Each of the first to third broadband filters can have, for example, a multi-cavity structure or a metal mirror structure.

[0259] FIG. 28 It can be used as FIG. 27 A diagram of another example of a broadband filter 2510 consisting of the first additional filter to the third additional filters 2501, 2502 and 2503.

[0260] refer to FIG. 28 The broadband filter 2510 may include a plurality of reflective layers 2513, 2514 and 2515 spaced apart from each other, and a plurality of cavities 2511 and 2512 disposed between the plurality of reflective layers 2513, 2514 and 2515. FIG. 28 Three reflective layers 2513, 2514 and 2515 and two cavities 2511 and 2512 are shown; however, the number of reflective layers 2513, 2514 and 2515 and cavities 2511 and 2512 can vary.

[0261] Each of reflective layers 2513, 2514, and 2515 may be a DBR. Each of reflective layers 2513, 2514, and 2515 may have a structure in which multiple material layers with different refractive indices are stacked alternately. Furthermore, each of cavities 2511 and 2512 may include a material with a specific refractive index, or two or more materials with different refractive indices.

[0262] FIG. 29 It can be used as FIG. 27 A diagram of another example of a broadband filter 2520 consisting of a first additional filter to a third additional filter 2501, 2502 or 2503.

[0263] refer to FIG. 29 The broadband filter 2520 may include two metal mirror layers 2522 and 2523 spaced apart from each other and a cavity 2521 disposed between the metal mirror layers 2522 and 2523.

[0264] FIG. 30 This is a schematic cross-sectional view of a spectral filter 3000 according to another example embodiment.

[0265] Reference FIG. 30 The spectral filter 3000 may include a first filter array 1410, a second filter array 1420, a short-wavelength absorption filter 1610 and a long-wavelength cutoff filter 1620 disposed on the first filter array 1410 and the second filter array 1420.

[0266] The first filter array 1410 may include a first filter 1411, a second filter 1412, and a third filter 1413 having a center wavelength in a first wavelength region, and the second filter array 1420 may include a fourth filter 1421, a fifth filter 1422, and a sixth filter 1423 having a center wavelength in a second wavelength region.

[0267] The first filter array 1410 can be any one of the first filter arrays 110 to 1010 described above, and the second filter array 1420 can be any one of the second filter arrays 120 to 1020 described above. Descriptions of the first filter array 1410 and the second filter array 1420 are omitted.

[0268] Short-wavelength absorption filter 1610 can be disposed in some of the filters among the first to sixth filters 1411, 1412, 1413, 1421, 1422 and 1423 (i.e., first filter 1411, third filter 1413 and fifth filter 1422), and long-wavelength cutoff filter 1620 can be disposed in other filters among the first to sixth filters 1411, 1412, 1413, 1421, 1422 and 1423 (i.e., second filter 1412, fourth filter 1421 and sixth filter 1423). Although FIG. 30 The illustration shows each of the short-wavelength absorption filter 1610 and the long-wavelength cutoff filter 1620 configured to correspond to one of the first to sixth filters 1411, 1412, 1413, 1421, 1422 and 1423, but the disclosure is not limited thereto, and each of the short-wavelength absorption filter 1610 and the long-wavelength cutoff filter 1620 may be configured to correspond to two or more of the first to sixth filters 1411, 1412, 1413, 1421, 1422 and 1423.

[0269] The short-wavelength absorption filter 1610 can, for example, block short-wavelength light such as visible light. The short-wavelength absorption filter 1610 can be manufactured, for example, by depositing silicon on some of the filters 1411, 1412, 1413, 1421, 1422, and 1423 (i.e., the first filter 1411, the third filter 1413, and the fifth filter 1422), wherein silicon is a material capable of absorbing visible light. The first filter 1411, the third filter 1413, and the fifth filter 1422, including the short-wavelength absorption filter 1610, can transmit near-infrared (NIR) light with wavelengths longer than visible light.

[0270] The long-wavelength cutoff filter 1620 can, for example, cut off light with long wavelengths such as NIR light. The long-wavelength cutoff filter 1620 may include an NIR light cutoff filter. The second filter 1412, the fourth filter 1421, and the sixth filter 1423, which include the long-wavelength cutoff filter 1620, can transmit visible light with wavelengths shorter than those of NIR light.

[0271] According to the embodiment, since the short-wavelength absorption filter 1610 and the long-wavelength cutoff filter 1620 are disposed on the first filter array 1410 and the second filter array 1420, a spectral filter 3000 having broadband characteristics capable of realizing the visible light band to the NIR band can be manufactured.

[0272] FIG. 31 This is a schematic block diagram of an image sensor 1000 according to an example embodiment.

[0273] refer to FIG. 31 The image sensor 1000 may include a spectral filter 9100, a pixel array 4100, a timing controller (T / C) 4010, a row decoder 4020, and an output circuit 4030. The spectral filter 9100 may include multiple filters that transmit light in different wavelength regions and are arranged in a 2D manner. The pixel array 4100 may include multiple pixels that detect light of different wavelengths transmitted through the multiple filters. Specifically, the pixel array 4100 may include pixels arranged in a 2D manner along multiple rows and columns. The row decoder 4020 may select one of the rows of the pixel array 4100 in response to a row address signal output from the timing controller 4010. The output circuit 4030 may output a light detection signal from the pixels arranged along the selected row, column by column. For this purpose, the output circuit 4030 may include a column decoder and an analog-to-digital converter (ADC). For example, the output circuit 4030 may include multiple ADCs arranged for each column between the column decoder and the pixel array 4100, or a single ADC arranged at the output of the column decoder. The timing controller 4010, line decoder 4020, and output circuit 4030 can be implemented as a single chip or as separate chips. A processor for processing the image signal output through the output circuit 4030 can be implemented as a single chip containing the timing controller 4010, line decoder 4020, and output circuit 4030. The pixel array 4100 can include multiple pixels that detect light of different wavelengths, and the pixels can be arranged in various ways.

[0274] FIG. 32 It is applicable FIG. 31 A plan view of an example of the spectral filter 9100 of the image sensor 1000.

[0275] refer to FIG. 32 The spectral filter 9100 may include multiple filter groups 9110 arranged in a 2D manner. Each filter group 9110 may include sixteen filters arranged in a 4×4 array (i.e., first filter F1, second filter F2, third filter F3, fourth filter F4, fifth filter F5, sixth filter F6, seventh filter F7, eighth filter F8, ninth filter F9, tenth filter F10, eleventh filter F11, twelfth filter F12, thirteenth filter F13, fourteenth filter F14, fifteenth filter F15 and sixteenth filter F16).

[0276] The first filter F1 and the second filter F2 can have center wavelengths UV1 and UV2 in the ultraviolet region. The third filter F3 to the fifth filter F5 can have center wavelengths B1 to B3 in the blue light region. The sixth filter F6 to the eleventh filter F11 can have center wavelengths G1 to G6 in the green light region. The twelfth filter F12 to the fourteenth filter F14 can have center wavelengths R1 to R3 in the red light region. The fifteenth filter F15 and the sixteenth filter F16 can have center wavelengths NIR1 and NIR2 in the NIR region.

[0277] FIG. 33 It is applicable FIG. 31 A plan view of another example of the spectral filter 9100 for an image sensor. For ease of illustration, FIG. 33 This is a plan view of a filter group 9120.

[0278] refer to FIG. 33 Each filter group 9120 may include nine filters (i.e., first filters F1 to ninth filters F9) arranged in a 3×3 array. First filters F1 and second filters F2 may have center wavelengths UV1 and UV2 in the ultraviolet region, and fourth filters F4, fifth filters F5, and seventh filters F7 may have center wavelengths B1 to B3 in the blue light region. Third filters F3 and sixth filters F6 may have center wavelengths G1 and G2 in the green light region, and eighth filters F8 and ninth filters F9 may have center wavelengths R1 and R2 in the red light region.

[0279] FIG. 34 It is applicable FIG. 31 A plan view of another example of the spectral filter 9100 for an image sensor. For ease of illustration, FIG. 34 This is a plan view of a 9130 filter group.

[0280] refer to FIG. 34Each filter group 9130 may include twenty-five filters arranged in a 5×5 array (i.e., filters F1 to F16 (first to sixteenth), F17 (seventeenth), F18 (eighteenth), F19 (nineteenth), F20 (twentieth), F21 (twenty-first), F22 (twenty-second), F23 (twenty-third), F24 (twenty-fourth), and F25 (twenty-fifth). Filters F1 to F3 may have center wavelengths UV1 to UV3 in the ultraviolet region, and filters F6, F7, F8, F11, and F12 may have center wavelengths B1 to B5 in the blue light region. The fourth filter F4, the fifth filter F5, the ninth filter F9, the sixteenth filter F16, the seventeenth filter F17, the twenty-first filter F21, and the twenty-second filter F22 can have center wavelengths G1 to G7 in the green light region, and the tenth filter F10, the thirteenth filter F13, the fourteenth filter F14, the fifteenth filter F15, the eighteenth filter F18, and the nineteenth filter F19 can have center wavelengths R1 to R6 in the red light region. The twentieth filter F20, the twenty-third filter F23, the twenty-fourth filter F24, and the twenty-fifth filter F25 can have center wavelengths NIR1 to NIR4 in the NIR region.

[0281] The image sensor 1000 with the aforementioned spectral filter can be used in various high-performance optical devices or high-performance electronic devices. Electronic devices may include, for example, smartphones, mobile phones, cellular phones, personal digital assistants (PDAs), laptops, personal computers (PCs), various portable devices, home appliances, security cameras, medical cameras, automobiles, Internet of Things (IoT) devices, and other mobile or non-mobile computing devices, but this disclosure is not limited thereto.

[0282] In addition to the image sensor 1000, the electronic device may also include a processor (e.g., an application processor (AP)) for controlling the image sensor, controlling multiple hardware or software components and performing various data processing and calculations by driving an operating system or application via the processor. The processor may also include a graphics processing unit (GPU) and / or an image signal processor. When the processor includes an image signal processor, the processor can be used to store and / or output images (or videos) acquired by the image sensor.

[0283] FIG. 35 This is a schematic block diagram of an electronic device ED01 including an image sensor 1000. (Reference) FIG. 35In the network environment ED00, electronic device ED01 can communicate with another electronic device ED02 through a first network ED98 (e.g., a short-range wireless communication network), or with another electronic device ED04 and / or server ED08 through a second network ED99 (e.g., a long-range wireless communication network). Electronic device ED01 can communicate with electronic device ED04 through server ED08. Electronic device ED01 may include a processor ED20, a memory ED30, an input device ED50, an audio output device ED55, a display device ED60, an audio module ED70, a sensor module ED76, an interface ED77, a haptic module ED79, a camera module ED80, a power management module ED88, a battery ED89, a communication module ED90, a user identification module ED96, and / or an antenna module ED97. In electronic device ED01, some components (e.g., the display device ED60) may be omitted, or other components may be added. Some components may be implemented as an integrated circuit. For example, the sensor module ED76 (e.g., a fingerprint sensor, an iris sensor, an illuminance sensor, etc.) can be implemented by embedding it in the display device ED60 (e.g., a display, etc.). Furthermore, when the image sensor 1000 includes spectral functionality, some functions of the sensor module ED76 (e.g., a color sensor and an illuminance sensor) can be implemented by the image sensor 1000, rather than by a separate sensor module.

[0284] Processor ED20 can control one or more other components (such as hardware and software components) of electronic device ED01 connected to processor ED20 by executing software (such as program ED40, etc.) and perform various data processing or calculations. As part of the data processing or calculation, processor ED20 can load commands and / or data received from other components (such as sensor module ED76, communication module ED90, etc.) into volatile memory ED32, process the commands and / or data stored in volatile memory ED32, and store the result data in non-volatile memory ED34. Processor ED20 may include a main processor ED21 (such as a central processing unit, application processor, etc.) and an auxiliary processor ED23 (such as a graphics processing unit, image signal processor, sensor hub processor, communication processor, etc.) that can operate independently of or with the main processor ED21. The auxiliary processor ED23 can use less power than the main processor ED21 and can perform specialized functions.

[0285] When the main processor ED21 is inactive (i.e., in sleep mode), the auxiliary processor ED23 can replace the main processor ED21, or when the main processor ED21 is active (i.e., in application execution mode), it can work together with the main processor ED21 to control the functions and / or states related to some components of the electronic device ED01 (e.g., display device ED60, sensor module ED76, communication module ED90, etc.). The auxiliary processor ED23 (e.g., image signal processor, communication processor, etc.) can be implemented as part of other functionally related components (e.g., camera module ED80, communication module ED90, etc.).

[0286] Memory ED30 can store various data required by the components of electronic device ED01 (e.g., processor ED20, sensor module ED76, etc.). Data may include, for example, software (e.g., program ED40, etc.) and input and / or output data regarding commands associated with it. Memory ED30 may include volatile memory ED32 and / or non-volatile memory ED34. Non-volatile memory ED34 may include internal memory ED36 fixedly installed in electronic device ED01 and removable external memory ED38.

[0287] The program ED40 can be stored as software in the memory ED30 and may include the operating system ED42, middleware ED44 and / or application ED46.

[0288] Input device ED50 can receive commands and / or data from outside electronic device ED01 (e.g., from a user) to be used by components of electronic device ED01 (e.g., processor ED20). Input device ED50 may include a microphone, mouse, keyboard, and / or digital pen (e.g., stylus).

[0289] Audio output device ED55 can output audio signals to the external device ED01. Audio output device ED55 may include a speaker and / or a receiver. The speaker can be used for general purposes such as multimedia playback or recording playback, and the receiver can be used to answer incoming calls. The receiver can be implemented by coupling it as part of the speaker or by using a separate, independent device.

[0290] Display device ED60 can visually provide information to the outside of electronic device ED01. Display device ED60 may include a display, holographic device or projector and control circuitry for controlling the corresponding device. Display device ED60 may include touch circuitry configured to detect touch and / or sensor circuitry configured to measure the intensity of the force generated by the touch (e.g., pressure sensor).

[0291] The audio module ED70 can convert sound into electrical signals or vice versa. The audio module ED70 can acquire sound through the input device ED50, or output sound through the speakers and / or headphones of another electronic device (such as electronic device ED02, etc.) connected to the audio output device ED55 and / or electronic device ED01 via wired or wireless means.

[0292] The sensor module ED76 can detect the operating status (e.g., power, temperature, etc.) or external environmental status (e.g., user status, etc.) of the electronic device ED01, and generate electrical signals and / or data values ​​corresponding to the detected status. The sensor module ED76 may include gesture sensors, gyroscope sensors, barometric pressure sensors, magnetic sensors, accelerometers, grip sensors, proximity sensors, color sensors, infrared (IR) sensors, biometric sensors, temperature sensors, humidity sensors, and / or illuminance sensors.

[0293] Interface ED77 can support one or more specified protocols for electronic device ED01 to connect to another electronic device (such as electronic device ED02, etc.) via wired or wireless means. Interface ED77 may include a High Definition Multimedia Interface (HDMI), a Universal Serial Bus (USB) interface, an SD card interface, and / or an audio interface.

[0294] The connection terminal ED78 may include a connector for physically connecting electronic device ED01 to another electronic device (such as electronic device ED02, etc.). The connection terminal ED78 may include an HDMI connector, a USB connector, an SD card connector, and / or an audio connector (such as a headphone connector, etc.).

[0295] The haptic module ED79 can convert electrical signals into mechanical stimuli (such as vibration, motion, etc.) or electrical stimuli that can be perceived by the user through touch or motion. The haptic module ED79 may include a motor, a piezoelectric device, and / or an electrical stimulation device.

[0296] The ED80 camera module can capture still images and video. The ED80 camera module may include a lens assembly with one or more lenses. FIG. 1 The image sensor 1000, image signal processor, and / or flash are included. The lens assembly included in the camera module ED80 can collect light emitted from the object for image capture.

[0297] The power management module ED88 can manage the power supplied to the electronic device ED01. The power management module ED88 can be implemented as part of a power management integrated circuit (PMIC).

[0298] Battery ED89 can supply power to the components of electronic device ED01. Battery ED89 may include non-rechargeable primary batteries, rechargeable secondary batteries, and / or fuel cells.

[0299] Communication module ED90 can establish a direct (wired) communication channel and / or a wireless communication channel between electronic device ED01 and another electronic device (e.g., electronic device ED02, electronic device ED04, server ED08, etc.), and supports communication through the established communication channel. Communication module ED90 can operate independently of processor ED20 (e.g., application processor, etc.) and may include one or more communication processors supporting wired and / or wireless communication. Communication module ED90 may include wireless communication module ED92 (e.g., cellular communication module, short-range wireless communication module, Global Navigation Satellite System (GNSS) communication module, etc.) and / or wired communication module ED94 (e.g., local area network (LAN) communication module, power line communication module, etc.). In the above communication modules, the corresponding communication module can communicate with another electronic device through a first network ED98 (e.g., a short-range communication network such as Bluetooth, WiFi Direct, or Infrared Data Association (IrDA)) or a second network ED99 (e.g., a long-range communication network such as a cellular network, the Internet, or computer network (LAN, WAN, etc.). These various types of communication modules can be integrated into a single component (e.g., a single chip) or implemented as multiple separate components (e.g., multiple chips). The wireless communication module ED92 can verify and authenticate the electronic device ED01 in a communication network such as the first network ED98 and / or the second network ED99 by using user information (e.g., International Mobile Subscriber Identity (IMSI)) stored in the user identification module ED96.

[0300] Antenna module ED97 can transmit signals and / or power to or from an external source (e.g., another electronic device). The antenna may include a transmitter formed with a conductive pattern on a substrate (e.g., a printed circuit board (PCB)). Antenna module ED97 may include one or more antennas. When antenna module ED97 includes multiple antennas, communication module ED90 can select from these antennas an antenna suitable for a communication method used in a communication network such as first network ED98 and / or second network ED99. Signals and / or power can be transmitted or received between communication module ED90 and another electronic device via the selected antenna. Other components besides the antenna (e.g., RFIC, etc.) may be included as part of antenna module ED97.

[0301] Some components can be connected to each other through communication methods between peripheral devices (such as bus, general purpose input and output (GPIO), serial peripheral interface (SPI), mobile industrial processor interface (MIPI), etc.) and can exchange signals (such as commands, data, etc.).

[0302] Commands or data can be sent or received between electronic device ED01 and external electronic device ED04 via server ED08 connected to the second network ED99. Electronic devices ED02 and ED04 can be of the same or different type as electronic device ED01. All or part of the operations performed in electronic device ED01 can be performed in one or more of electronic devices ED02, ED04, and ED08. For example, when electronic device ED01 needs to perform a function or service, it can request one or more electronic devices to perform part or all of that function or service, instead of performing it itself. The one or more electronic devices receiving the request can perform additional functions or services related to the request and send the results of the execution back to electronic device ED01. Cloud computing, distributed computing, and / or client-server computing technologies can be used for this purpose.

[0303] FIG. 36 yes FIG. 35 A schematic block diagram of the ED80 camera module. (Reference) FIG. 36 The camera module ED80 may include a lens assembly CM10, a flash CM20, and an image sensor 1000 (e.g., FIG. 12 The camera module ED80 may include an image sensor 1000, an image stabilizer CM40, a memory CM50 (e.g., buffer memory), and / or an image signal processor CM60. A lens assembly CM10 can collect light emitted from an object for image capture. The camera module ED80 may include multiple lens assemblies CM10, in which case the camera module ED80 may be a dual-camera system, a 360-degree camera, or a spherical camera. Some lens assemblies CM10 may have the same lens properties (e.g., angle of view, focal length, autofocus, f-number, optical zoom, etc.) or different lens properties. Lens assemblies CM10 may include wide-angle lenses or telephoto lenses.

[0304] The flash CM20 can emit light to enhance light emitted or reflected from an object. The flash CM20 may include one or more light-emitting diodes (e.g., red, green, and blue (RGB) LEDs, white LEDs, infrared LEDs, ultraviolet LEDs, etc.) and / or a xenon lamp. The image sensor 1000 may include... FIG. 1The image sensor 1000 converts light emitted or reflected from an object and transmitted through the lens assembly CM10 into electrical signals, thereby obtaining an image corresponding to the object. The image sensor 1000 may include one or more sensors selected from image sensors with different properties, such as an RGB sensor, a black-and-white (BW) sensor, an IR sensor, or a UV sensor. Each sensor included in the image sensor 1000 may be implemented as a charge-coupled device (CCD) sensor and / or a complementary metal-oxide-semiconductor (CMOS) sensor.

[0305] Image stabilizer CM40 can respond to movement of camera module ED80 or electronic device ED01 including camera module ED80 by moving one or more lenses or image sensor 1000 included in lens assembly CM10 in a specific direction, or by compensating for negative effects caused by movement by controlling the movement characteristics of image sensor 1000 (e.g., adjusting readout timing). Image stabilizer CM40 can detect movement of camera module ED80 or electronic device ED01 by using a gyroscope sensor (not shown) or accelerometer sensor (not shown) disposed inside or outside camera module ED80. Image stabilizer CM40 can be implemented optically.

[0306] The memory CM50 can store some or all of the image data acquired by the image sensor 1000 for subsequent image processing operations. For example, when multiple images are acquired at high speed, only the low-resolution image is displayed, while the acquired raw data (e.g., Bayer pattern data, high-resolution data, etc.) is stored in the memory CM50. The memory CM50 can then be used to transfer the raw data of the selected (e.g., user-selected) image to the image signal processor CM60. The memory CM50 can be incorporated into the memory ED30 of the electronic device ED01, or configured as a separate memory operating independently.

[0307] Image signal processor CM60 can perform image processing on images acquired by image sensor 1000 or image data stored in memory CM50. Image processing may include depth map generation, 3D modeling, panorama generation, feature point extraction, image compositing, and / or image compensation (e.g., noise reduction, resolution adjustment, brightness adjustment, blurring, sharpening, softening, etc.). Image signal processor CM60 can perform control (e.g., exposure time control or readout timing control, etc.) on components included in camera module ED80 (e.g., image sensor 1000, etc.). Images processed by image signal processor CM60 can be stored again in memory CM50 for additional processing or provided to external components of camera module ED80 (e.g., memory ED30, display device ED60, electronic device ED02, electronic device ED04, server ED08, etc.). Image signal processor CM60 may be incorporated into processor ED20 or configured as a separate processor operating independently of processor ED20. When the image signal processor CM60 is configured as a processor separate from the processor ED20, the image processed by the image signal processor CM60 can undergo additional image processing by the processor ED20 and then be displayed by the display device ED60.

[0308] Electronic device ED01 may include multiple camera modules ED80 with different attributes or functions. In this case, one of the camera modules ED80 may be a wide-angle camera, while another may be a telephoto camera. Similarly, one of the camera modules ED80 may be a front-facing camera, while another may be a rear-facing camera.

[0309] The image sensor 1000 according to the embodiment can be applied to FIG. 37 The mobile phone or smartphone 5100m shown in (a) FIG. 37 The tablet computer or smart tablet computer 5200 shown in (b) FIG. 37 The digital camera or camcorder 5300 shown in (c) FIG. 37 The notebook computer 5400 shown in (d) FIG. 37 The television or smart TV 5500 shown in (e) is an example. For instance, a smartphone 5100m or a smart tablet 5200 may include multiple high-resolution cameras, each equipped with a high-resolution image sensor. By using high-resolution cameras, depth information of objects in an image can be extracted, the image can be adjusted for focus, or objects in an image can be automatically identified.

[0310] Furthermore, the image sensor 1000 can be applied to FIG. 38 The smart refrigerator 5600 shown in (a) FIG. 38 The security camera 5700 shown in (b) FIG. 38Robot 5800 shown in (c) FIG. 38 Examples include the medical camera 5900 shown in (d). For instance, the smart refrigerator 5600 can automatically identify food in the refrigerator using an image sensor and notify the user of the presence of specific food, the type of food input or output, etc., via a smartphone. The security camera 5700 can provide ultra-high resolution images and can identify objects or people in images in dark environments using high sensitivity. The robot 5800 can be set up in disaster or industrial sites where people cannot directly access it and can provide high-resolution images. The medical camera 5900 can provide high-resolution images for diagnosis or surgery, and therefore can dynamically adjust the field of view.

[0311] Furthermore, the image sensor 1000 can be applied to, for example... FIG. 38 The vehicle 6000 is shown in (e). The vehicle 6000 may include a plurality of onboard cameras 6010, 6020, 6030, and 6040 disposed at different locations. Each of the onboard cameras 6010, 6020, 6030, and 6040 may include an image sensor according to an embodiment. The vehicle 6000 can provide the driver with various information about the interior or periphery of the vehicle 6000 by using the onboard cameras 6010, 6020, 6030, and 6040, thereby automatically identifying objects or people in the images and providing information necessary for autonomous driving.

[0312] According to an example embodiment, a spectral filter with broadband characteristics can be realized by providing a filter using a first metal reflective layer and a filter using a second metal reflective layer on a plane. According to another example embodiment, a spectral filter with broadband characteristics can be realized by providing a filter using a metal reflective layer and a filter using a Bragg reflective layer on a plane. According to another example embodiment, a spectral filter with improved transmittance can be realized by providing a filter using a first metal reflective layer and a filter using both a second metal reflective layer and a Bragg reflective layer on a plane. According to another example embodiment, an image sensor including the above-described spectral filter and an electronic device including the image sensor can be provided.

[0313] It should be understood that the embodiments described herein should be considered in a descriptive sense and not for limiting purposes only. The description of features or aspects in each embodiment should generally be considered as applicable to other similar features or aspects in other embodiments. Although one or more embodiments have been described with reference to the accompanying drawings, those skilled in the art will understand that various changes in form and detail may be made without departing from the spirit and scope defined by the appended claims.

Claims

1. A spectral filter, comprising: A first filter having a center wavelength in a first wavelength region; as well as The second filter has the center wavelength in the second wavelength region. The first filter includes: Two first metallic reflective layers arranged vertically and spaced apart from each other; and The first cavity disposed between the two first metal reflective layers, and The second filter includes: A second metallic reflective layer and a Bragg reflective layer arranged vertically and spaced apart from each other; and A second cavity is disposed between the second metal reflective layer and the Bragg reflective layer. The second metal reflective layer and the Bragg reflective layer are made of different materials.

2. The spectral filter according to claim 1, wherein, The center wavelength in the first wavelength region is shorter than the center wavelength in the second wavelength region.

3. The spectral filter according to claim 2, wherein, The two first metal reflective layers include Al, Ag, Au, Ti, W or TiN, and the second metal reflective layer includes Cu, Ag, Au, Ti, W or TiN.

4. The spectral filter according to claim 2, wherein, The second metal reflective layer also includes polycrystalline silicon.

5. The spectral filter according to claim 1, wherein, The first metal reflective layer and the second metal reflective layer have a thickness of 10 nm to 80 nm.

6. The spectral filter according to claim 1, wherein, The two first metal reflective layers include Al, Ag, Au, Ti, W or TiN, and the second metal reflective layer includes Cu.

7. The spectral filter according to claim 1, wherein, The first filter further includes a first filter array, which includes a plurality of first filters with different center wavelengths, and the second filter further includes a second filter array, which includes a plurality of second filters with different center wavelengths.

8. The spectral filter according to claim 1, wherein, The center wavelength of the first filter is based on the thickness or effective refractive index of the first cavity, and the center wavelength of the second filter is based on the thickness or effective refractive index of the second cavity.

9. The spectral filter according to claim 1, wherein, The first filter further includes a first dielectric layer and a second dielectric layer respectively disposed below and above the first cavity, and the second filter further includes a third dielectric layer and a fourth dielectric layer respectively disposed below and above the second cavity.

10. The spectral filter according to claim 9, wherein, Each of the first dielectric layer, the second dielectric layer, the third dielectric layer, and the fourth dielectric layer has a single-layer or multi-layer structure.

11. The spectral filter according to claim 9, wherein, The thickness or effective refractive index of each of the first and second dielectric layers is based on the center wavelength of the first filter, and the thickness or effective refractive index of each of the third and fourth dielectric layers is based on the center wavelength of the second filter.

12. The spectral filter according to claim 1 further includes a plurality of microlenses disposed at the first filter and the second filter.

13. The spectral filter according to claim 1 further includes a color filter disposed on the same plane as the first filter and the second filter.

14. The spectral filter of claim 1 further comprises an additional filter disposed at the first filter and the second filter and configured to transmit a specific wavelength band.

15. The spectral filter according to claim 14, wherein, The additional filter includes a color filter or a broadband filter.

16. The spectral filter according to claim 1, wherein, A short-wavelength absorption filter is disposed at a portion of the first filter and the second filter, and a long-wavelength cutoff filter is disposed at the other portion of the first filter and the second filter.

17. An image sensor, comprising: Spectral filters; as well as A pixel array that receives light transmitted through the spectral filter. The spectral filter includes: A first filter having a center wavelength in a first wavelength region; and The second filter has the center wavelength in the second wavelength region. The first filter includes: A plurality of first metallic reflective layers arranged vertically and spaced apart from each other; and A first cavity disposed between the plurality of first metal reflective layers, and The second filter includes: A second metallic reflective layer and a Bragg reflective layer arranged vertically and spaced apart from each other; and A second cavity is disposed between the second metal reflective layer and the Bragg reflective layer. The plurality of first metal reflective layers include Al, Ag, Au, Ti, W, or TiN, and the second metal reflective layer includes Cu. The first filter further includes a first dielectric layer and a second dielectric layer respectively disposed below and above the first cavity, and the second filter further includes a third dielectric layer and a fourth dielectric layer respectively disposed below and above the second cavity. The center wavelength of the first filter is based on the thickness or effective refractive index of each of the first and second dielectric layers, and the center wavelength of the second filter is based on the thickness or effective refractive index of each of the third and fourth dielectric layers.

18. The image sensor according to claim 17, wherein, The pixel array includes a plurality of pixels, and each of the plurality of pixels includes a wiring layer, the wiring layer including a driving circuit and a photodiode disposed thereon.

19. The image sensor according to claim 17, wherein, The center wavelength in the first wavelength region is shorter than the center wavelength in the second wavelength region.

20. The image sensor according to claim 17, wherein, The first filter further includes a first filter array, which includes a plurality of first filters with different center wavelengths, and the second filter further includes a second filter array, which includes a plurality of second filters with different center wavelengths.

21. The image sensor according to claim 17, wherein, The center wavelength of the first filter is based on the thickness or effective refractive index of the first cavity, and the center wavelength of the second filter is based on the thickness or effective refractive index of the second cavity.

22. The image sensor according to claim 17, wherein, The spectral filter also includes a plurality of microlenses disposed at the first filter and the second filter.

23. The image sensor according to claim 17, wherein, The spectral filter also includes a color filter disposed on the same plane as the first filter and the second filter.

24. The image sensor according to claim 17, wherein, The spectral filter also includes an additional filter disposed at the first filter and the second filter and configured to transmit a specific wavelength band.

25. The image sensor of claim 17 further includes a timing controller, a line decoder, and an output circuit.

26. An electronic device comprising the image sensor according to claim 17.

27. The electronic device according to claim 26, wherein, The electronic devices include mobile phones, smartphones, tablet computers, smart tablet computers, digital cameras, camcorders, laptop computers, televisions, smart televisions, smart refrigerators, security cameras, robots, or medical cameras.

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