Image sensor

Abstract

To provide an image sensor with improved reliability.SOLUTION: The image sensor 100a includes a sensor substrate 110 including a plurality of first pixels 111 configured to sense light of first wavelengths and a plurality of second pixels 112 configured to sense light of second wavelengths different from the first wavelengths, a first color filter 130a and a second color filter 130b disposed on the sensor substrate and corresponding to the first pixels and the second pixels, respectively, a transparent spacer 140 disposed on the first and second color filters, and a plurality of first and second light receiving units disposed on the spacer and configured to receive incident light. At least one or more meta-microlens arrays 151 including a plurality of nanoposts NP1 arranged to converge on a second pixel, and at least two or more upper anti-reflection layers 160 disposed on a light incident surface of the meta-microlens array, wherein the upper anti-reflection layers are stacked to overlap each other in a vertical direction, and each of the upper anti-reflection layers has a refractive index that increases as the upper anti-reflection layer is closer to the meta-microlens array.SELECTED DRAWING: Figure 5

Description

[Technical Field]

[0001] The present invention relates to an image sensor, and more particularly to an image sensor in which a meta-microlens is applied to reduce the reflectance of the meta-microlens. [Background technology]

[0002] Image sensors typically have a structure for focusing incident light. In one embodiment of the light concentrator, a meta-microlens array is used. Reflection of light from the light-incident surface of the meta-microlens array ultimately reduces the efficiency of the sensing element. Therefore, there is a need to develop technology for anti-reflection coatings, such as oxide films, that reduce the reflectivity of the light-incident surface of the microlens array. Summary of the Invention [Problem to be solved by the invention]

[0003] The present invention has been made in consideration of the above-mentioned problems in the prior art, and an object of the present invention is to provide an image sensor with improved reliability. [Means for solving the problem]

[0004] In order to achieve the above object, an image sensor according to one aspect of the present invention includes a sensor substrate including a plurality of first pixels that sense light of a first wavelength and a plurality of second pixels that sense light of a second wavelength different from the first wavelength; first and second color filters arranged on the upper part of the sensor substrate and corresponding to the first and second pixels, respectively; a transparent spacer arranged on the first and second color filters; at least one meta-microlens array arranged on the spacer and including a plurality of nanoposts arranged to focus incident light onto the plurality of first pixels and the plurality of second pixels; and at least two or more upper anti-reflection layers arranged on the light incident surface of the meta-microlens array, wherein the upper anti-reflection layers are stacked so as to overlap each other vertically, and each refractive index increases as they approach the meta-microlens array.

[0005] According to one embodiment, the image sensor includes a sensor substrate including a plurality of first pixels that sense light of a first wavelength and a plurality of second pixels that sense light of a second wavelength different from the first wavelength; a transparent spacer disposed on the sensor substrate; a first color filter and a second color filter disposed between the sensor substrate and the spacer and corresponding to the first pixels and the second pixels, respectively; a color filter fence disposed between the first color filter and the second color filter; a first meta-microlens array disposed on the spacer and including a plurality of first nanoposts arranged to focus incident light onto the plurality of first pixels and the plurality of second pixels; a second meta-microlens array including a plurality of second nanoposts arranged on top of the spacer and positioned at horizontal positions different from the horizontal positions of the plurality of first nanoposts; a first etch stopper arranged between the spacer and the first meta-microlens array; and at least two or more upper anti-reflection layers arranged on the light incident surface of the second meta-microlens array, wherein the upper anti-reflection layers are stacked and overlap each other vertically, and each refractive index is larger the closer it is to the second meta-microlens array, and the refractive index of the upper anti-reflection layers is smaller than the refractive index of the meta-microlens and larger than the refractive index of air.

[0006] According to one embodiment, the image sensor includes a sensor substrate including a plurality of first pixels that sense light of a first wavelength and a plurality of second pixels that sense light of a second wavelength different from the first wavelength; at least two or more lower anti-reflection layers disposed on an upper surface of the sensor substrate; a transparent spacer disposed on the lower anti-reflection layers; a first color filter and a second color filter disposed between the sensor substrate and the spacer and corresponding to the first pixels and the second pixels, respectively; a first meta-microlens array disposed on the spacer and including a plurality of first nanoposts arranged to focus incident light onto the plurality of first pixels and the plurality of second pixels; and a transparent spacer disposed on the first meta-microlens array and configured to adjust the horizontal positions of the plurality of first nanoposts. a second meta-microlens array including a plurality of second nanoposts arranged at horizontal positions different from the position of the first nanoposts at the spacer and the first meta-microlens array; a first etch stopper arranged between the spacer and the first meta-microlens array; and at least two or more upper anti-reflection layers arranged on the light entrance surface of the second meta-microlens array, wherein the upper anti-reflection layers are stacked so as to overlap each other in the vertical direction, and each of the upper anti-reflection layers has a refractive index that is larger the closer it is to the second meta-microlens array, and each of the first meta-microlens array and the second meta-microlens array changes the phase of light of the first wavelength to focus the light of the first wavelength on a respective first pixel, and changes the phase of light of the second wavelength to focus the light of the second wavelength on a respective second pixel. [Effects of the Invention]

[0007] According to the image sensor of the present invention, a multi-layer anti-reflection film is formed on the top of the meta-microlens array, and the refractive index of each of the anti-reflection films is different, thereby reducing the reflection of light generated at the light incident surface of the meta-microlens array and improving the efficiency of the sensor. In addition, the anti-reflection film is simply stacked vertically, eliminating the need for separate photolithography and etching processes, thereby reducing process costs and optimizing the process.

[0008] The effects of the present invention are not limited to the effects described above, and other effects not mentioned will be clearly derived and understood by a person having ordinary skill in the art to which the exemplary embodiments of the present invention pertain from the following description. In other words, unintended effects resulting from implementing the exemplary embodiments of the present invention will also be derived from the exemplary embodiments of the present invention by a person having ordinary skill in the art. [Brief explanation of the drawings]

[0009] [Figure 1] 1 is a block diagram illustrating an image sensor according to an embodiment of the present invention; [Figure 2] 2A to 2C are diagrams illustrating various pixel arrangements of a pixel array of an image sensor according to an embodiment of the present invention. [Figure 3] 2A to 2C are diagrams illustrating various pixel arrangements of a pixel array of an image sensor according to an embodiment of the present invention. [Figure 4] 2A to 2C are diagrams illustrating various pixel arrangements of a pixel array of an image sensor according to an embodiment of the present invention. [Figure 5] 1 is a cross-sectional view of an image sensor according to an embodiment of the present invention; [Figure 6] FIG. 2 is a plan view showing the arrangement of pixels in a pixel array. [Figure 7] 1 is a plan view illustrating an example of the configuration of a meta-microlens array included in an image sensor according to an embodiment of the present invention. [Figure 8] 10 is a cross-sectional view of an image sensor according to another embodiment of the present invention. [Figure 9] FIG. 10 is a cross-sectional view of an image sensor according to yet another embodiment of the present invention. [Figure 10A] FIG. 6 is an enlarged view of a first example of region A in FIG. 5. [Figure 10B] FIG. 6 is an enlarged view of a second example of region A in FIG. 5. [Figure 10C] FIG. 6 is an enlarged view of a third example of region A in FIG. 5. [Figure 10D] FIG. 6 is an enlarged view of a fourth example of region A in FIG. 5. [Figure 10E]FIG. 6 is an enlarged view of a fifth example of region A in FIG. 5. [Figure 10F] FIG. 6 is an enlarged view of a sixth example of region A in FIG. 5. [Figure 10G] FIG. 7 is an enlarged view of a seventh example of region A in FIG. 5. [Figure 10H] FIG. 7 is an enlarged view of an eighth example of region A in FIG. 5. [Figure 10I] FIG. 9 is an enlarged view of a ninth example of region A in FIG. 5. [Figure 10J] FIG. 13 is an enlarged view of a tenth example of region A in FIG. 5. [Figure 10K] FIG. 6 is an enlarged view of an eleventh example of region A in FIG. 5. [Figure 10L] FIG. 6 is an enlarged view of a twelfth example of region A in FIG. 5. [Figure 11] 4 is a graph showing reflectance according to wavelength of an image sensor according to an embodiment of the present invention; [Figure 12] 1 is a graph showing average reflectance of an image sensor according to an embodiment of the present invention. [Figure 13] FIG. 1 is a block diagram of an electronic device including a multi-camera module. [Figure 14] FIG. 14 is a detailed block diagram of the camera module of FIG. 13. [Figure 15] 1 is a block diagram showing a configuration of an image sensor according to an embodiment of the present invention; [Figure 16] 1 is a block diagram that schematically illustrates an electronic device including an image sensor according to one embodiment. [Figure 17] FIG. 17 is a block diagram illustrating the camera module of FIG. 16. DETAILED DESCRIPTION OF THE INVENTION

[0010] The present invention may be modified in various ways and may have various forms, and therefore, an embodiment will be described in detail with reference to the drawings. However, this is not intended to limit the present invention to the specific disclosed form. Furthermore, the embodiment described below is merely an example, and various modifications are possible from such an embodiment.

[0011] The use of any examples or exemplary terms is merely for the purpose of illustrating the technical idea in detail, and the scope is not limited by such examples or exemplary terms, since the scope is not limited by the claims.

[0012] Unless otherwise specified, in this specification, the vertical direction is defined as the Z direction, and the first and second horizontal directions are each defined as horizontal directions perpendicular to the Z direction. The first horizontal direction is referred to as the X direction, and the second horizontal direction is referred to as the Y direction. The vertical level refers to the height level in the vertical direction (Z direction). The first horizontal direction and horizontal width refer to the length in the horizontal direction (X direction and / or Y direction), and the vertical length refers to the length in the vertical direction (Z direction).

[0013] FIG. 1 is a block diagram illustrating an image sensor according to an embodiment of the present invention.

[0014] Referring to FIG. 1, an image sensor 100 according to this embodiment includes a pixel array 10 and a number of circuits for controlling the pixel array 10 .

[0015] In this embodiment, the circuitry for controlling the pixel array 10 includes a column driver 20, a row driver 30, a timing controller 40, and a readout circuit 50.

[0016] The image sensor 100 operates according to a control command received from the image processor 70, converts light transmitted from an external object into an electrical signal, and outputs the electrical signal to the image processor 70. The image sensor 100 is a complementary metal oxide semiconductor (CMOS) image sensor.

[0017] The pixel array 10 includes a plurality of pixel units PXU arranged in a two-dimensional array structure along a plurality of row lines and a plurality of column lines in a matrix. In this specification, a row (or row) refers to a group of unit pixels arranged horizontally among the plurality of unit pixels included in the pixel array 10, and a column (or column) refers to a group of unit pixels arranged vertically among the plurality of unit pixels included in the pixel array 10.

[0018] Each of the pixel units PXU has a multi-pixel structure including a plurality of photodiodes. In each of the pixel units PXU, the photodiodes receive light transmitted from an object and generate charges. The image sensor 100 performs an auto-focus function using a phase difference between pixel signals generated by the photodiodes included in each of the pixel units PXU. Each of the pixel units PXU includes a pixel circuit for generating a pixel signal from the charges generated by the photodiodes.

[0019] The column driver 20 includes a correlated double sampler, an analog-to-digital converter, etc. The correlated double sampler is connected through a column line to a pixel unit PXU included in a row selected by a row selection signal supplied by the row driver 30, and performs correlated double sampling to detect a reset voltage and a pixel voltage. The analog-to-digital converter converts the reset voltage and the pixel voltage detected by the correlated double sampler into digital signals and transmits them to a readout circuit 50.

[0020] The readout circuit 50 includes a latch or buffer circuit for temporarily storing digital signals, an amplifier circuit, etc., and temporarily stores or amplifies the digital signals received from the column driver 20 to generate image data. The operation timings of the column driver 20, row driver 30, and readout circuit 50 are determined by a timing controller 40, which operates according to control commands transmitted from an image processor 70.

[0021] The image processor 70 processes the image data output from the readout circuit 50 and outputs the processed image data to a display device or stores the processed image data in a storage device such as a memory. When the image sensor 100 is installed in an autonomous vehicle, the image processor 70 processes the processed image data and transmits the processed image data to a main controller or the like that controls the autonomous vehicle.

[0022] 2 to 4 are diagrams showing various pixel arrangements of a pixel array of an image sensor according to an embodiment of the present invention.

[0023] The pixel array 10 includes a plurality of pixels that sense light of different wavelengths. The pixel arrangement can be implemented in various ways. For example, FIGS. 2 to 4 illustrate various pixel arrangements of the pixel array 10 of the image sensor 100.

[0024] First, FIG. 2 shows a Bayer pattern commonly used in image sensors 100. Referring to FIG. 2, one unit pattern includes four quadrant regions, and the first to fourth quadrant regions are blue (B), green (G), red (R), and green (G) pixels, respectively. Such unit patterns are repeatedly arranged two-dimensionally along a first direction (X direction) and a second direction (Y direction). That is, within a 2×2 array of unit patterns, two green (G) pixels are arranged diagonally on one side, and one blue (B) pixel and one red (R) pixel are arranged diagonally on the other side. Looking at the overall pixel arrangement, a first row in which a plurality of green (G) pixels and a plurality of blue (B) pixels are alternately arranged along the first direction, and a second row in which a plurality of red (R) pixels and a plurality of green (G) pixels are alternately arranged along the first direction, are repeatedly arranged along the second direction.

[0025] The pixel array 10 may be arranged in various ways, such as a tetrahedral or nona-lattice pattern, in addition to the Bayer pattern. For example, referring to FIG. 3, a CYGM-type arrangement is possible in which a magenta pixel (M), a cyan pixel (C), a yellow pixel (Y), and a green pixel (G) form one unit pixel pattern. Referring to FIG. 4, an RGBW-type arrangement is also possible in which a green pixel (G), a red pixel (R), a blue pixel (B), and a white pixel (W) form one unit pattern. Although not shown, the unit pattern may have a 3x2 array shape. The pixels of the pixel array 10 may also be arranged in various ways depending on the color characteristics of the image sensor 100. Hereinafter, the pixel array 10 of the image sensor 100 will be described as having a Bayer pattern, but the operating principle can also be applied to pixel arrays of other types than the Bayer pattern.

[0026] FIG. 5 is a cross-sectional view of an image sensor according to one embodiment of the present invention.

[0027] Referring to FIG. 5, an image sensor 100a is an embodiment corresponding to the image sensor 100 described with reference to FIGS. 1 to 4. The image sensor 100a includes a sensor substrate 110 including a plurality of first pixels 111 that sense a first wavelength and a plurality of second pixels 112 that sense light of a second wavelength different from the first wavelength. The first wavelength is in the green light region of the visible light wavelength band. The second wavelength is in the red light region of the visible light wavelength band. Although the third and fourth pixels are not shown in this drawing, they may be illustrated in another horizontal cross-sectional view. That is, the first and second pixels 111 and 112 of the present invention correspond to the third and fourth pixels.

[0028] The image sensor 100a includes two or more lower anti-reflection layers 120 disposed (directly or indirectly) on the upper surface 110S of the sensor substrate 110. In Fig. 5, the lower anti-reflection layers 120 include a first lower anti-reflection layer 121 and a second lower anti-reflection layer 122. However, the lower anti-reflection layers 120 are not limited thereto and may include three, four, or more lower anti-reflection layers.

[0029] The lower anti-reflection layer 120 improves the light utilization efficiency of the pixel array by reducing the amount of incident light reflected from the upper surface 110S of the sensor substrate 110. That is, the lower anti-reflection layer 120 helps the sensor substrate 110 to sense external incident light.

[0030] As a result, the image sensor 100a (which may be included in the image sensor 100 or may be the image sensor 100 itself) may have the following improved performance: improved light sensitivity, improved light sensing and / or image generation performance, improved efficiency in power consumption for sensing or generating an image from sensed light, or reduced power consumption without a decrease in sensing / image generation performance.

[0031] Each of the first lower antireflection layer 121 and the second lower antireflection layer 122 is formed to a thickness of about 80 nm to 120 nm.

[0032] The image sensor 100a includes a first color filter 130a disposed on the first pixel 111 (e.g., so as to at least partially overlap the first pixel 111 in the Z direction (a direction extending perpendicular to the upper surface 110S of the sensor substrate)) and a second color filter 130b disposed on the second pixel 112 (e.g., so as to at least partially overlap the second pixel 112 in the Z direction), and the first color filter 130a and the second color filter 130b are disposed on the upper part of the sensor substrate 110. Although not shown, the image sensor 100a may further include a third color filter disposed on the third pixel 113 and a fourth color filter disposed on the fourth pixel 114.

[0033] For example, the first color filter 130a and the fourth color filter are green color filters that transmit only green light, the second color filter 130b is a blue color filter that transmits only blue light, and the third color filter is a red color filter that transmits only red light.

[0034] When the image sensor 100a includes a first meta-microlens array 151 capable of not only simple light collection but also color separation, light that has already been color-separated to a considerable extent by the first meta-microlens array 151 moves toward the first to fourth pixels (111, 112, 113, 114), so that even when color filters (130a, 130b) are used, light loss is small, minimized, or prevented.

[0035] The use of the color filters (130a, 130b) further improves the color purity of the image sensor 100a. However, the color filters (130a, 130b) are not essential components and may be omitted in some embodiments. For example, if the color separation efficiency of the first meta-microlens array 151 is sufficiently high, exceeding or reaching a certain reference value, the color filters (130a, 130b) may be omitted.

[0036] The image sensor 100a including the pixel array can provide a sufficient amount of light to the pixels even when the pixel size is small because light loss (e.g., the phenomenon in which incident light passing through the image sensor 100a is lost without reaching the pixel) caused by a color filter, such as an organic color filter, is reduced, minimized, or prevented.

[0037] As a result, the image sensor 100a (which may be included in the image sensor 100 or may be the image sensor 100 itself) may have the following improved performance: improved light sensitivity, improved light sensing and / or image generation performance, improved efficiency in power consumption required for light sensing or generating an image corresponding to the sensed light, or reduced power consumption without impairing light sensing and / or image generation performance.

[0038] Therefore, it is possible to manufacture ultra-high resolution, ultra-small, high sensitivity image sensors with hundreds of millions of pixels or more. Such ultra-high resolution, ultra-small, high sensitivity image sensors are adopted in a variety of high performance optical devices or high performance electronic devices. Such electronic devices include, but are not limited to, smartphones, mobile phones, cellular phones, PDAs (personal digital assistants), 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.

[0039] In addition to the image sensor 100a, the electronic device may further include a processor, such as an application processor (AP), that controls the image sensor. The processor runs an operating system (OS) or an application program (application program) to control multiple hardware or software components and perform various data processing and calculations. The processor may further include a graphic processing unit (GPU) and / or an image signal processor. If the processor includes an image signal processor, the image (or video) acquired by the image sensor may be stored and / or output using the processor.

[0040] The image sensor 100a includes a color filter fence 131 disposed between the first color filter 130a and the second color filter 130b (e.g., between the first and second color filters 130a and 130b adjacent to each other in a horizontal direction parallel to the upper surface 110S). The color filter fence 131 is disposed at the center (e.g., horizontally) of each of the first color filter 130a and the second color filter 130b. That is, the first color filter 130a and the second color filter 130b are each formed to surround the outer periphery of one or more color filter fences 131. The color filter fences 131 are disposed at regular intervals in the horizontal direction. The horizontal intervals shown in FIG. 5 are merely an example, and the intervals between the color filter fences 131 are not limited thereto. The image sensor 100a includes an insulating film 131a between the color filter fence 131 and the lower anti-reflection layer 120 and the first and second color filters 130a and 130b. The material of the insulating film 131a includes, for example, SiO 2 .

[0041] The image sensor 100a includes a transparent spacer 140 disposed on the first color filter 130a and the second color filter 130b. Details of the spacer 140 will be described with reference to FIG.

[0042] The image sensor 100a includes a first meta-microlens array 151 and a first etch stopper ES1 disposed between the spacer 140 and the first meta-microlens array 151.

[0043] The first meta-microlens array 151 is supported by the spacer 140 and includes first nanoposts NP1 with a high refractive index that change the phase of incident light, and a first dielectric layer DL1 disposed between the first nanoposts NP1 and made of a dielectric material with a lower refractive index than the first nanoposts NP1. The dielectric material of the first dielectric layer DL1 includes, for example, air or SiO2. The first nanoposts NP1 have different diameters. The first nanoposts NP1 are also spaced apart horizontally by different distances.

[0044] Meanwhile, the first meta-microlens array 151 can focus incident light regardless of wavelength and focuses the light by changing the phase according to the wavelength. In one embodiment, the first meta-microlens array 151 is divided into a green light focusing region for focusing green light, a blue light focusing region for focusing blue light, and a red light focusing region for focusing red light.

[0045] The first meta-microlens array 151 includes first nanoposts NP1 whose size, shape, spacing, and / or arrangement are determined so that green light is branched and focused at the first and fourth pixels (111, 114), blue light is branched and focused at the second pixel 112, and red light is branched and focused at the third pixel 113. Meanwhile, the thickness of the first meta-microlens array 151 along the third direction (Z direction) is similar to the height of the first nanoposts NP1 and is 500 nm to 1500 nm.

[0046] To design the first meta-microlens array 151 for color separation, the performance of a plurality of candidate color separation lens arrays is evaluated based on evaluation factors such as color separation spectrum, optical efficiency, and signal-to-noise ratio, and the structures of the green, blue, red, and infrared pixel corresponding regions are optimized. For example, after determining a target numerical value for each evaluation factor in advance, the structures of the green, blue, red, and infrared pixel corresponding regions are optimized by minimizing the sum of the differences from the target numerical values ​​for the plurality of evaluation factors. Alternatively, the performance is indexed for each evaluation factor, and the structures of the green, blue, red, and infrared pixel corresponding regions are optimized to maximize the value indicating the performance.

[0047] The first meta-microlens array 151 includes a plurality of first etch stoppers ES1 disposed below the first nanoposts NP1. Each first etch stopper ES1 is disposed between the corresponding first nanopost NP1 and the spacer 140 to protect the spacer 140 from damage during the process of forming the first nanoposts NP1. The first etch stopper ES1 has a relatively high etching selectivity with respect to the spacer 140 and includes a transparent dielectric material. For example, the first etch stopper ES1 includes at least one material selected from aluminum oxide (AlO), hafnium oxide (HfO), and silicon nitride (SiN). The first etch stopper ES1 has a thickness that protects the underlying layer, i.e., the spacer 140, without impairing the optical properties of the first meta-microlens array 151. The thickness of the first etch stopper ES1 is, for example, about 3 nm to about 50 nm, or about 5 nm to about 15 nm.

[0048] To minimize the increase in reflectivity due to the first etch stoppers ES1, the first etch stoppers ES1 are arranged so as not to completely cover the entire surface of the spacers 140. That is, the first etch stoppers ES1 are arranged so as to cover only a portion of the upper surface of the spacers 140. For example, each first etch stopper ES1 is arranged only below its corresponding first nanopost NP1, and the first etch stoppers ES1 are spaced apart so that the upper surface of the spacers 140 directly contacts the lower surface of the first dielectric layer DL1 in the region between the first etch stoppers ES1. Because the refractive index of the spacers 140 and the refractive index of the first dielectric layer DL1 are substantially the same, almost no reflection occurs at the interface between the spacers 140 and the first dielectric layer DL1. Therefore, by minimizing the overall area of ​​the first etch stoppers ES1, the increase in reflectivity at the interface between the spacers 140 and the first etch stoppers ES1 can be minimized.

[0049] The image sensor 100a includes at least two or more upper anti-reflection layers 160 disposed on the light incident surface of the first meta-microlens array 151. In FIG. 5, the upper anti-reflection layers 160 are illustrated as including three layers, but may include four layers as in FIG. 8, or may include four or more layers, although not shown.

[0050] In this embodiment, the plurality of upper anti-reflection layers 160 includes a first upper anti-reflection layer 161, a second upper anti-reflection layer 162, and a third upper anti-reflection layer 163. The first upper anti-reflection layer 161, the second upper anti-reflection layer 162, and the third upper anti-reflection layer 163 are stacked so as to overlap each other in the vertical direction (Z direction).

[0051] The first upper antireflection layer 161 is disposed at the top of the plurality of upper antireflection layers 160, and the second upper antireflection layer 162 is disposed on the lower surface (directly below) of the first upper antireflection layer 161. The third upper antireflection layer 163 is disposed on the lower surface (directly below) of the second upper antireflection layer 162, and therefore the vertical position of the third upper antireflection layer 163 is the lowest.

[0052] The refractive index of the plurality of upper antireflection layers 160 is smaller than that of first meta-microlens array 151 and larger than that of air. For example, the refractive index of the plurality of upper antireflection layers 160 (the individual refractive index of each upper antireflection layer 160) is smaller than that of first meta-microlens array 151 and larger than that of air.

[0053] In one embodiment, when the refractive index of first meta-microlens array 151 is approximately 1.69, the refractive index of each of first upper anti-reflective layer 161, second upper anti-reflective layer 162, and third upper anti-reflective layer 163 is less than 1.69 and greater than 1.

[0054] Each of the upper anti-reflective layers 160 includes at least one or a combination of Al2O2, HfO, SiO2, AlOC, AlON, AlOCN, Ta2O5, or TiO2. For example, each of the first upper anti-reflective layer 161, the second upper anti-reflective layer 162, and the third upper anti-reflective layer 163 independently includes at least one or a combination of Al2O3, HfO, SiO2, AlOC, AlON, AlOCN, Ta2O5, or TiO2.

[0055] The first upper anti-reflection layer 161, the second upper anti-reflection layer 162, and the third upper anti-reflection layer 163 are formed so that their refractive indexes (e.g., their respective refractive indices) increase as they become closer to the first meta-microlens array 151 (e.g., as the distance from the first meta-microlens array 151 decreases in the Z direction).

[0056] For example, if a particular upper antireflection layer of the plurality of upper antireflection layers 160 is positioned closer to the first meta-microlens array 151 in the Z direction than the other upper antireflection layers, the particular upper antireflection layer has a higher refractive index than the other upper antireflection layers. In one embodiment, the refractive index of the second upper antireflection layer 162 is lower than the refractive index of the third upper antireflection layer 163 but higher than the refractive index of the first upper antireflection layer 161. Also, in one embodiment, the refractive index of the plurality of upper antireflection layers 160 increases linearly by about 0.2 per 100 nm of thickness in the Z direction.

[0057] In another embodiment, the refractive index increases linearly as the vertical level decreases from the upper surface 160u (e.g., the upper surface 161u of the first upper anti-reflection layer 161) to the lower surface 160r (e.g., the lower surface 163r of the third upper anti-reflection layer 163) in the Z direction relative to the total thickness 160T of the plurality of upper anti-reflection layers 160.

[0058] That is, as the vertical level decreases in the Z direction along the total thickness 160T (eg, from the upper surface 160u toward the upper surface 110S and / or the lower surface 160r), the refractive index at that vertical level increases.

[0059] For example, the refractive index of a particular portion of the plurality of upper anti-reflection layers 160 increases as the vertical level at which that portion is located decreases. In one embodiment, each individual layer of each upper anti-reflection layer 160 has a constant or nearly constant refractive index throughout its thickness in the Z direction, with the lower layer having a higher refractive index than the upper layer in the case of two adjacent layers (e.g., upper / lower anti-reflection layers in direct contact). This results in a step change in refractive index between layers as the vertical level decreases along the total thickness 160T. This step change in refractive index corresponds to a linear increase in refractive index from the upper surface 160u to the lower surface 160r along the total thickness 160T, e.g., an increase of about 0.2 per 100 nm of thickness.

[0060] In one embodiment, the refractive index of a particular individual upper anti-reflective layer also increases along the thickness in the Z direction (e.g., from the top surface to the bottom surface, i.e., toward the top surface 110S), and in this case, the refractive index also has a linear increase with thickness. For example, if the first upper anti-reflective layer 161 has a refractive index of about 1.22 and a thickness of 1,000 Å, the second upper anti-reflective layer 162 has a refractive index of about 1.35 and a thickness of 1,000 Å. Similarly, if the second upper anti-reflective layer 162 has a refractive index of about 1.35 and a thickness of 1,000 Å, the third upper anti-reflective layer 163 has a refractive index of about 1.46 and a thickness of 1,000 Å.

[0061] In the upper antireflection layer 160, the refractive index increases as the vertical level decreases (e.g., toward the upper surface 110S in the Z direction), so when light incident on the first meta-microlens array 151 (e.g., light that passes through the upper antireflection layer 160 and enters the light incident surface of the first meta-microlens array 151, e.g., the upper surface 151u in Figure 5) is reflected, the reflected light travels from the high refractive index region to the low refractive index region.

[0062] Therefore, the reflected incident light travels from an upper anti-reflection layer with a higher refractive index (e.g., the third upper anti-reflection layer 163) to an upper anti-reflection layer with a lower refractive index (e.g., the second upper anti-reflection layer 162), and is totally reflected or refracted at the interface between those layers (e.g., the interface between the second and third upper anti-reflection layers 162, 163). As a result, the reflection frequency decreases (e.g., the amount of incident light reflected from the first meta-microlens array 151 to the outside of the image sensor 100 through the entire thickness in the Z direction decreases), and thus the intensity of the reflected light (e.g., the intensity of incident light reflected to the outside of the image sensor 100a through the upper surface 161u of the first upper anti-reflection layer 161, i.e., the light incident surface of the first upper anti-reflection layer or the plurality of upper anti-reflection layers 160) also decreases.

[0063] In one embodiment, if the incident angle of incident light is greater than a critical angle determined by the refractive indices of the third and second upper antireflection layers (163, 162) after being reflected from the third upper antireflection layer 163 to the second upper antireflection layer 162, the incident light is totally reflected from the interface (e.g., the lower surface of the second upper antireflection layer) to the third upper antireflection layer 163. The same traveling path of incident light applies to the interface between the first upper antireflection layer 161 and the second upper antireflection layer 162 and to the interface between the first meta-microlens array 151 and the third upper antireflection layer 163. As a result, the upper antireflection layer 160 (also referred to as an antireflection coating) reduces, minimizes, or prevents reflectivity at the light incident surface (e.g., the upper surface 151u) of the first meta-microlens array 151. Therefore, the image sensor 100a (which may be included in the image sensor 100 or may be the image sensor 100 itself) may have the following improved performance: improved light sensitivity, improved light sensing and / or image generation performance, improved efficiency in power consumption required for sensing light or generating an image corresponding to the sensed light, or reduced power consumption without performance degradation.

[0064] The first upper anti-reflection layer 161, the second upper anti-reflection layer 162, and the third upper anti-reflection layer 163 have different thicknesses, and the first upper anti-reflection layer 161, the second upper anti-reflection layer 162, and the third upper anti-reflection layer 163 have thicknesses of about 100 Å to 2000 Å.

[0065] FIG. 6 is a plan view showing the arrangement of pixels in a pixel array.

[0066] 6 shows a pixel arrangement when the pixel array 10 of the image sensor 100 has a Bayer pattern arrangement as shown in FIG. 2. Such an arrangement is intended to divide incident light into unit patterns such as the Bayer pattern for sensing. For example, the first pixel 111 and the fourth pixel 114 are green pixels that sense green light, the second pixel 112 is a blue pixel that senses blue light, and the third pixel 113 is a red pixel that senses red light. In the 2×2 array unit pattern, the first pixel 111 and the fourth pixel 114, which are green pixels, are arranged diagonally on one side, and the second pixel 112 and the third pixel 113, which are blue and red pixels, are arranged diagonally on the other side.

[0067] The spacer 140 is disposed between the sensor substrate 110 and the first meta-microlens array 151 to maintain a constant distance between the sensor substrate 110 and the first meta-microlens array 151. The spacer 140 includes a dielectric material that is transparent to visible light, such as SiO2 or siloxane-based spin-on glass (SOG), and has a lower refractive index than the first nanoposts NP1 of the first meta-microlens array 151 and low absorption in the visible light range. The thickness of the spacer 140 is determined based on the focal length of the light focused by the first meta-microlens array 151. For example, the reference wavelength (λ0) is selected within a range of approximately 1 / 2 to 1.5 times the focal length of the light.

[0068] Assuming that the reference wavelength (λ0) is 540 nm for green light, the pitch of the pixels (111, 112, 113, 114) is 0.8 μm, and the refractive index (n) of the spacer 140 at a wavelength of 540 nm is 1.46, the focal length (f) of the green light, i.e., the distance between the bottom surface of the first meta-microlens array 151 and the point where the green light converges, is approximately 1.64 μm, and the thickness of the spacer 140 is selected within a range of approximately 0.82 μm to approximately 2.46 μm.

[0069] The first meta-microlens array 151 is supported by the spacer 140 and includes first nanoposts NP1 with a high refractive index that change the phase of incident light, and a first dielectric layer DL1 disposed between the first nanoposts NP1 and made of a dielectric material with a lower refractive index than the first nanoposts NP1. The dielectric material of the first dielectric layer DL1 includes, for example, air or SiO2.

[0070] FIG. 7 is a plan view illustrating an example of the configuration of a meta-microlens array included in an image sensor according to an embodiment of the present invention.

[0071] 7, the plurality of first meta-microlens arrays 151 arranged in the pixel array 10 include, in one embodiment, first to fourth lenses (151a, 151b, 151c, 151d) that simply focus incident light onto the first to fourth pixels (111, 112, 113, 114) without color separation. For example, the first to fourth lenses (151a, 151b, 151c, 151d) simply focus incident light onto the corresponding first to fourth pixels (111, 112, 113, 114), respectively, and color separation occurs in the color filters (130a, 130b). In addition, in one embodiment, the first meta-microlens array 151 not only focuses light, but also focuses light by changing the phase according to wavelength. In one embodiment, the phase of light at a first wavelength is changed to focus the light at the first pixel 111, the phase of light at a second wavelength to focus the light at the second pixel 112, the phase of light at a third wavelength to focus the light at the third pixel 113, and the phase of light at a fourth wavelength to focus the light at the fourth pixel 114. Apart from the wavelength-specific focusing of the first meta-microlens array 151, color separation occurs independently and redundantly from the color filters (130a, 130b). The discussion below regarding FIG. 7 will further discuss the case of simple focusing. In order to focus incident light, the first nanoposts NP1 in each of the first to fourth lenses (151a, 151b, 151c, 151d) are arranged symmetrically along the first direction (X direction) and the second direction (Y direction) with respect to the center of each of the first to fourth lenses (151a, 151b, 151c, 151d). In particular, the first nanoposts NP1 arranged in the central region of each of the first to fourth lenses (151a, 151b, 151c, 151d) have the largest diameter, and the diameter of the first nanoposts NP1 gradually decreases with increasing distance from the central region of each of the first to fourth lenses (151a, 151b, 151c, 151d).

[0072] 7, the first to fourth lenses (151a, 151b, 151c, 151d) function as a single lens for all of the first to fourth photosensitive cells of the corresponding first to fourth pixels (111, 112, 113, 114). In another embodiment, the first meta-microlens array 151 is configured to form focal points on the first to fourth photosensitive cells of the first to fourth pixels (111, 112, 113, 114), respectively.

[0073] Meanwhile, the spacer 140 provides a flat surface for forming the first meta-microlens array 151 on the color filters (130a, 130b). The spacer 140, together with the color filters (130a, 130b), also serves as a spacer for determining the distance between the sensor substrate 110 and the first meta-microlens array 151. The distance between the sensor substrate 110 and the first meta-microlens array 151 is determined by the focal length of the first meta-microlens array 151. For example, the thickness of the spacer 140 and the thickness of the color filters (130a, 130b) are the same as the focal length of the first meta-microlens array 151. As a result, light collected by the first meta-microlens array 151 is focused onto the sensor substrate 110. If the focal length of the first meta-microlens array 151 is sufficiently short, the spacer 140 can be omitted.

[0074] 8 and 9 are cross-sectional views of image sensors according to other embodiments of the present invention.

[0075] 8 and 9 will be referred to together with FIG. 5, and differences from FIG. 5 will be mainly described.

[0076] Referring to FIG. 8, the upper anti-reflection layer 160 included in the image sensor 100b is composed of four layers. The upper anti-reflection layer 160 further includes a fourth upper anti-reflection layer 164. However, the number of layers of the upper anti-reflection layer 160 is not limited thereto and may be four or more. The fourth upper anti-reflection layer 164 is disposed below the third upper anti-reflection layer 163. The refractive index of the fourth upper anti-reflection layer 164 is greater than the refractive index of the third upper anti-reflection layer 163 and less than the refractive index of the first meta-microlens array 151. In the case of FIG. 8, the refractive index of the upper anti-reflection layers 160 increases linearly by about 0.2 for every 100 nm of thickness in the vertical direction (Z direction). That is, the lower the vertical level, the greater the refractive index. In one embodiment, when the refractive index of the third upper anti-reflection layer 163 is about 1.22 and the thickness is 1000 Å, the refractive index of the fourth upper anti-reflection layer 164 is about 1.67.

[0077] Referring to FIG. 9, the image sensor 100c includes two meta-microlens arrays. In one embodiment, the image sensor 100c includes a first meta-microlens array 151 and a second meta-microlens array 152. The second meta-microlens array 152 is disposed on top of the first meta-microlens array 151. That is, incident light entering the image sensor 100c first passes through the second meta-microlens array 152 and then passes through the first meta-microlens array 151. The first meta-microlens array 151 and the second meta-microlens array 152 have substantially the same thickness. The second meta-microlens array 152 includes second nanoposts NP2 with a high refractive index that shifts the phase of the incident light, and a second dielectric layer DL2 disposed between the second nanoposts NP2 and made of a dielectric material with a lower refractive index than the second nanoposts NP2. The second nanoposts NP2 and the second dielectric layer DL2 are made of substantially the same material as the first nanoposts NP1 and the first dielectric layer DL1. In one embodiment, the horizontal position of the second nanoposts NP2 is different from the horizontal position of the plurality of first nanoposts NP1. That is, instead of the same first nanoposts NP1 being disposed below the second nanoposts NP2, a first dielectric layer DL1 is disposed. The second meta-microlens array 152 may be capable of not only simple focusing like the first meta-microlens array 151, but also color separation. Each of the first meta-microlens array 151 and the second meta-microlens array 152 included in the image sensor 100c may be combined into two types: one capable of focusing only, and the other capable of shifting the phase of light of a first wavelength to focus the light of the first wavelength on each first pixel and shifting the phase of light of a second wavelength to focus the light of the second wavelength on each second pixel.

[0078] In one embodiment, both first meta-microlens array 151 and second meta-microlens array 152 are capable of focusing only incident light. In one embodiment, both first meta-microlens array 151 and second meta-microlens array 152 are capable of changing the phase of incident light by wavelength and focusing the light on each pixel corresponding to the wavelength of the incident light. In one embodiment, first meta-microlens array 151 is capable of focusing only all incident light, and second meta-microlens array 152 is capable of changing the phase of incident light by wavelength and focusing the light on each pixel corresponding to the wavelength of the incident light. In one embodiment, first meta-microlens array 151 is capable of changing the phase of incident light by wavelength and focusing the light on each pixel corresponding to the wavelength of the incident light, and second meta-microlens array 152 is capable of focusing only all incident light.

[0079] Image sensor 100c further includes a second etch stopper ES2 disposed between first meta-microlens array 151 and second meta-microlens array 152. Second etch stopper ES2 is substantially identical to first etch stopper ES1.

[0080] 10A to 10L are enlarged views of various embodiments of region A in FIG.

[0081] 10A, upper anti-reflection layer 160a is disposed (e.g., directly or indirectly) on the upper surface of first meta-microlens array 151. However, this is only one embodiment, and upper anti-reflection layer 160a may be disposed on the upper surface of second meta-microlens array. Upper anti-reflection layer 160a includes first upper anti-reflection layer 161a, second upper anti-reflection layer 162a, and third upper anti-reflection layer 163a.

[0082] Holes 161ah are formed in the first upper antireflection layer 161a, and the holes are exposed to the outside. The holes 161ah are arranged two-dimensionally at periodic intervals within the first upper antireflection layer 161a. The cross-sectional area of ​​the holes 161ah is constant in the horizontal direction. No holes are formed in the second upper antireflection layer 162a and the third upper antireflection layer 163a. ​​The levels of the top surfaces of the first, second, and third upper antireflection layers (161a, 162a, 163a) are the same (e.g., flat or substantially flat in the X and Y directions).

[0083] 10B, the upper anti-reflection layer 160b is disposed on the upper surface of the first meta-microlens array 151. The upper anti-reflection layer 160b includes a first upper anti-reflection layer 161b, a second upper anti-reflection layer 162b, and a third upper anti-reflection layer 163b.

[0084] Holes (161bh, 162bh) are formed in the first upper anti-reflection layer 161b and the second upper anti-reflection layer 162b, respectively, and are exposed to the outside. The holes (161bh, 162bh) have the same horizontal width and position, and are formed sequentially or simultaneously. The holes 161bh overlap with the respective holes 162bh in the Z direction. These holes are arranged two-dimensionally periodically. No holes are formed in the third upper anti-reflection layer 163b.

[0085] 10C, the upper anti-reflection layer 160c is disposed on the upper surface of the first meta-microlens array 151. The upper anti-reflection layer 160c includes a first upper anti-reflection layer 161c, a second upper anti-reflection layer 162c, and a third upper anti-reflection layer 163c.

[0086] Holes (161ch, 162ch, 163ch) are formed in the first, second, and third upper anti-reflection layers (161c, 162c, 163c), respectively, and are exposed to the outside. The horizontal widths and positions of the holes are identical, and the holes are formed sequentially or simultaneously. The hole 161ch overlaps with each of the holes (162ch, 163ch) in the Z direction. The holes are arranged two-dimensionally and periodically. The holes expose a portion of the upper surface of the first meta-microlens array 151 to the outside.

[0087] 10D, an upper anti-reflection layer 160d is disposed on the upper surface of the first meta-microlens array 151. The upper anti-reflection layer 160d includes a first upper anti-reflection layer 161d, a second upper anti-reflection layer 162d, and a third upper anti-reflection layer 163d.

[0088] Holes 161dh are formed in the first upper antireflection layer 161d and are exposed to the outside. The horizontal cross-sectional area of ​​the holes 161dh is tapered, narrowing as it approaches the first meta-microlens array 151 side. The holes 161dh are arranged two-dimensionally and periodically. No holes are formed in the second and third upper antireflection layers (162d, 163d). The top surfaces of the first, second, and third upper antireflection layers (161d, 162d, 163d) are at the same level (for example, flat or substantially flat in the X and Y directions).

[0089] 10E, the upper anti-reflection layer 160e is disposed on the upper surface of the first meta-microlens array 151. The upper anti-reflection layer 160e includes a first upper anti-reflection layer 161e, a second upper anti-reflection layer 162e, and a third upper anti-reflection layer 163e.

[0090] Holes (161eh, 162eh) are formed in the first and second upper anti-reflection layers (161e, 162e), respectively, and are exposed to the outside. The horizontal cross-sectional area of ​​the holes (161eh, 162eh) is tapered, narrowing toward the first meta-microlens array 151. The sidewalls of the holes formed in the first and second upper anti-reflection layers (161e, 162e) are formed continuously (e.g., there is no abrupt change in cross-sectional area or shape at the interface between the bottom of the hole 161eh and the top of the hole 162eh), so that the two holes (161eh, 162eh) essentially define one continuous tapered hole. The holes are formed sequentially or simultaneously. The holes are arranged two-dimensionally periodically. No holes are formed in the third upper anti-reflection layer 163e.

[0091] 10F, an upper anti-reflection layer 160f is disposed on the upper surface of the first meta-microlens array 151. The upper anti-reflection layer 160f includes a first upper anti-reflection layer 161f, a second upper anti-reflection layer 162f, and a third upper anti-reflection layer 163f.

[0092] The first, second, and third upper antireflection layers (161f, 162f, 163f) have holes (161fh, 162fh, 163fh) formed therein, respectively, and exposed to the outside. The horizontal cross-sectional area of ​​the holes is tapered so that it becomes narrower as it approaches the first meta-microlens array 151 side.

[0093] The sidewalls of the holes (161fh, 162fh, 163fh) are formed continuously (e.g., there are no discontinuous changes in cross-sectional area or shape at the boundary between holes 161fh and 162fh, and between holes 162fh and 163fh), and the holes have a continuous tapered shape that penetrates through the first and third anti-reflection layers (161f, 163f) and are defined as a single hole.

[0094] The holes are formed sequentially or simultaneously and are arranged periodically in two dimensions, and a part of the upper surface of the first meta-microlens array 151 is exposed to the outside by such holes.

[0095] 10G, an upper anti-reflection layer 160g is disposed on the upper surface of the first meta-microlens array 151. The upper anti-reflection layer 160g includes a first upper anti-reflection layer 161g, a second upper anti-reflection layer 162g, and a third upper anti-reflection layer 163g.

[0096] A plurality of holes 163gh are formed periodically in a two-dimensional pattern in the third upper antireflection layer 163g disposed at the bottom. A second upper antireflection layer 162g disposed on the third upper antireflection layer 163g covers the outer surface of the third layer, and a first upper antireflection layer 161g disposed on the second layer covers the outer surface of the second layer.

[0097] The second anti-reflection layer 162g is formed to fill the holes 163gh of the third layer, and itself includes a plurality of holes 162gh that are two-dimensionally periodic.

[0098] The first anti-reflection layer 161g is formed to fill the holes 162gh of the second layer, and itself includes a plurality of holes 161gh that are two-dimensionally periodic.

[0099] In the horizontal direction, the cross-sectional area of ​​the holes 163gh in the third layer is larger than that of the holes 162gh in the second layer, which are larger than that of the holes 161gh in the first layer. The holes in the first and second layers are not exposed to the outside, but the holes in the third layer are exposed to the outside.

[0100] 10H, an upper anti-reflection layer 160h is disposed on the upper surface of the first meta-microlens array 151. The upper anti-reflection layer 160h includes a first upper anti-reflection layer 161h, a second upper anti-reflection layer 162h, and a third upper anti-reflection layer 163h.

[0101] A plurality of holes 163hh are formed in a two-dimensionally periodic pattern in the third antireflection layer 163h, and the second antireflection layer 162h is formed to cover the third layer and fill the holes.

[0102] The second layer includes a plurality of periodic holes 162hh, and the first layer is formed to fill the holes 162hh. The vertical level of the top surface of the first antireflection layer 161h is constant (e.g., flat or substantially flat in the X and Y directions). The horizontal cross-sectional area of ​​the holes 163hh in the third layer is larger than that of the holes 162hh in the second layer.

[0103] Referring to FIG. 10I, an upper anti-reflection layer 160i is disposed on the upper surface of the first meta-microlens array 151.

[0104] The upper anti-reflection layer 160i includes a first upper anti-reflection layer 161i, a second upper anti-reflection layer 162i, and a third upper anti-reflection layer 163i. The third layer has a plurality of periodically arranged holes 163ih, and the second layer is formed to cover the outer surface of the third layer and fill the holes.

[0105] The first layer is disposed over the outer surface of the second layer. The vertical level of the top surfaces of the first and second anti-reflection layers (161i, 162i) is constant (e.g., flat or substantially flat).

[0106] 10J, the upper anti-reflection layer 160j is disposed on the upper surface of the first meta-microlens array 151. The upper anti-reflection layer 160j includes first and third upper anti-reflection layers (161j, 163j).

[0107] A plurality of holes 163jh are periodically formed in the third layer, and the horizontal cross section of each hole has a shape that widens toward the meta-microlens array 151.

[0108] The second layer fills the holes of the third layer and includes a plurality of holes 162jh. The first layer fills the holes of the second layer and includes a plurality of holes 161jh.

[0109] The cross-sectional areas decrease in the order of 163jh, 162jh, and 161jh, and 163jh and 162jh are not exposed to the outside, but 161jh is exposed to the outside.

[0110] 10K, an upper anti-reflection layer 160k is disposed on the upper surface of the first meta-microlens array 151. A plurality of holes 163kh are periodically arranged in the third layer 163k, and the holes have a shape that widens toward the meta-microlens array 151.

[0111] The second layer fills the holes in the third layer and includes a plurality of holes 162kH, which the first layer fills to maintain a constant (e.g., flat or substantially flat) top vertical surface. The holes in the third layer have a larger horizontal cross-sectional area than the holes in the second layer.

[0112] Referring to FIG. 10L, a top anti-reflection layer 160l is disposed on the top surface of the first meta-microlens array 151.

[0113] A plurality of holes 163lh are periodically formed in the third upper anti-reflection layer 163l, and the horizontal cross section of each hole has a shape that widens toward the lens array.

[0114] The second layer covers the outer surface of the third layer and fills the holes, and the first layer covers the second layer, and the top surfaces of the first and second layers have a constant vertical level (e.g., flat or substantially flat).

[0115] FIG. 11 is a graph showing reflectance as a function of wavelength of an image sensor according to an embodiment of the present invention.

[0116] Referring to FIG. 11, the X-axis represents wavelength. The Y-axis represents reflectance for each image sensor. The wavelength band on the X-axis is 400 nm to 700 nm, which is similar to the wavelength band of visible light. The following focuses on the green band, 520 nm. A represents a case where a single top anti-reflection layer is formed using a conventional oxide film. B represents a case where a triple top anti-reflection layer is formed. C represents a case where a quadruple top anti-reflection layer is formed. Referring to the graph, it can be seen that around 520 nm, case A has the highest reflectance of approximately 8% to 9%. Around 520 nm, cases B and C have reflectances of approximately 5% to 6%, which are relatively lower than case A. The peak reflectance for case A is approximately 9.5%, the peak reflectance for case B is approximately 7.0%, and the peak reflectance for case C is approximately 6.6%, indicating that the peak values ​​decrease in the order of A, B, and C. That is, compared to a single layer, the refractive index of the multi-layer structure of the present invention increases toward the bottom, and the reflectance is effectively reduced as the number of multi-layer structures increases.

[0117] FIG. 12 is a graph showing the average reflectance of an image sensor according to one embodiment of the present invention.

[0118] Referring to FIG. 12, the Y axis represents the average reflectance for each image sensor. A, B, and C are the same as those in FIG. 11. Looking closely at the average reflectance for each case, in case A, the average reflectance is about 5.8%, in case B, the average reflectance is about 4%, and in case C, the average reflectance is about 4.2%. In other words, compared to the conventional case where a single oxide layer is formed, it can be seen that when a multi-layer structure is formed as in the present invention and the refractive index of the multi-layer structure increases toward the bottom, the average reflectance in the visible light wavelength band is effectively reduced.

[0119] Figure 13 is a block diagram of an electronic device including a multi-camera module, and Figure 14 is a detailed block diagram of the camera module of Figure 13.

[0120] Referring to FIG. 13, an electronic device 1000 includes a camera module group 1100, an application processor 1200, a PMIC (power management IC) 1300, and an external memory 1400.

[0121] The camera module group 1100 includes multiple camera modules (1100a, 1100b, 1100c). Although the drawings show an embodiment in which three camera modules (1100a, 1100b, 1100c) are arranged, the embodiment is not limited thereto. In one embodiment, the camera module group 1100 may include only two camera modules or may be modified to include n camera modules (where n is a natural number greater than or equal to four).

[0122] Referring to FIG. 14, the camera module 1100b includes a prism 1105, an optical path folding element (OPFE) 1110, an actuator 1130, an image sensing device 1140, and a storage 1150.

[0123] Here, the detailed configuration of one camera module 1100b will be described in more detail, but the following description also applies equally to other camera modules (1100a, 1100c) depending on the embodiment.

[0124] The prism 1105 includes a reflecting surface 1107 made of a light-reflecting material, and changes the path of incident light (L) from the outside.

[0125] In one embodiment, the prism 1105 changes the path of light (L) incident in a first direction (X direction) to a second direction (Y direction) perpendicular to the first direction (X direction). The prism 1105 also changes the path of light (L) incident in the first direction (X direction) to the perpendicular second direction (Y direction) by rotating the reflective surface 1107 of the light-reflecting material around a central axis 1106 in a direction A or by rotating the central axis 1106 in a direction B. In this case, the OPFE 1110 also moves in the first direction (X direction), second direction (Y direction), and third direction (Z direction).

[0126] In one embodiment, as shown, the maximum rotation angle of prism 1105 in the A direction is less than or equal to 15° in the positive (+) A direction and greater than 15° in the negative (-) A direction, although the embodiment is not so limited.

[0127] In one embodiment, prism 1105 moves in the positive (+) or negative (-) B direction by approximately 20°, or between 10° and 20°, or between 15° and 20°, where the angle of movement is the same angle in the positive (+) or negative (-) B direction, or moves to approximately the same angle in a range of approximately 1°.

[0128] In one embodiment, the prism 1105 moves the reflective surface 1107 of the light-reflecting material in a third direction (Z direction) parallel to the extension direction of the central axis 1106 .

[0129] The OPFE 1110 includes, for example, m optical lenses (where m is a natural number) in groups. The m lenses move in a second direction (Y direction) to change the optical zoom ratio of the camera module 1100b. For example, if the basic optical zoom ratio of the camera module 1100b is Z, when the m optical lenses included in the OPFE 1110 are moved, the optical zoom ratio of the camera module 1100b is changed to an optical zoom ratio of 3Z, 5Z, or more than 5Z.

[0130] The actuator 1130 moves the OPFE 1110 or the optical lens to a specific position. For example, the actuator 1130 adjusts the position of the optical lens so that the image sensor 1142 is located at the focal length of the optical lens for accurate sensing.

[0131] The image sensing device 1140 includes an image sensor 1142, control logic 1144, and memory 1146. The image sensor 1142 senses an image of a sensing target using light (L) provided through an optical lens. The control logic 1144 controls the overall operation of the camera module 1100b. For example, the control logic 1144 controls the operation of the camera module 1100b according to a control signal provided via a control signal line CSLb.

[0132] The memory 1146 stores information necessary for the operation of the camera module 1100b, such as calibration data 1147. The calibration data 1147 includes information necessary for the camera module 1100b to generate image data using light (L) provided from an external source. The calibration data 1147 includes, for example, information regarding the degree of rotation, the focal length, and the optical axis. If the camera module 1100b is implemented in the form of a multi-state camera in which the focal length varies depending on the position of the optical lens, the calibration data 1147 includes a focal length value for each position (or state) of the optical lens and information regarding autofocus.

[0133] The storage 1150 stores image data sensed through the image sensor 1142. The storage 1150 is disposed outside the image sensing device 1140 and is implemented in a stacked form on the sensor chip that constitutes the image sensing device 1140. In one embodiment, the storage 1150 is implemented using an EEPROM (Electrically Erasable Programmable Read-Only Memory), but the embodiment is not limited thereto.

[0134] 13 and 14, in one embodiment, each of the multiple camera modules (1100a, 1100b, 1100c) includes an actuator 1130. As a result, each of the multiple camera modules (1100a, 1100b, 1100c) includes the same or different calibration data 1147 due to the operation of the actuator 1130 included therein.

[0135] In one embodiment, one camera module (e.g., 1100b) of the multiple camera modules (1100a, 1100b, 1100c) is a folded lens type camera module including the above-mentioned prism 1105 and OPFE 1110, and the remaining camera modules (e.g., 1100a, 1100c) are vertical type camera modules that do not include the prism 1105 and OPFE 1110, but are not limited to this.

[0136] In one embodiment, one camera module (e.g., 1100c) among the plurality of camera modules (1100a, 1100b, 1100c) is a vertical depth camera that extracts depth information using, for example, infrared rays (IR). In this case, the application processor 1200 merges image data provided by the vertical depth camera with image data provided by the other camera modules (e.g., 1100a or 1100b) to generate a 3D depth image.

[0137] In one embodiment, at least two camera modules (e.g., 1100a, 1100b) of the plurality of camera modules (1100a, 1100b, 1100c) have different fields of view (fields of view) from each other, for example, but not limited to, the optical lenses of at least two camera modules (e.g., 1100a, 1100b) of the plurality of camera modules (1100a, 1100b, 1100c) are different from each other.

[0138] In one embodiment, the viewing angles of the camera modules (1100a, 1100b, 1100c) are different from each other, and in this case, the optical lenses included in the camera modules (1100a, 1100b, 1100c) are also different from each other, but this is not a limitation.

[0139] In one embodiment, the multiple camera modules (1100a, 1100b, 1100c) are arranged to be physically separated from one another. That is, instead of the multiple camera modules (1100a, 1100b, 1100c) sharing the same sensing area of ​​a single image sensor 1142, an independent image sensor 1142 is arranged inside each of the multiple camera modules (1100a, 1100b, 1100c).

[0140] 13, the application processor 1200 includes an image processing unit 1210, a memory controller 1220, and an internal memory 1230. The application processor 1200 is implemented separately from the camera modules 1100a, 1100b, and 1100c. For example, the application processor 1200 and the camera modules 1100a, 1100b, and 1100c are implemented separately on separate semiconductor chips.

[0141] The image processing device 1210 includes a number of sub-image processors (1212a, 1212b, 1212c), an image generator 1214, and a camera module controller 1216.

[0142] The image processing device 1210 includes a plurality of sub-image processors (1212a, 1212b, 1212c) corresponding to the number of the plurality of camera modules (1100a, 1100b, 1100c).

[0143] Image data generated from each camera module (1100a, 1100b, 1100c) is provided to the corresponding sub-image processor (1212a, 1212b, 1212c) via separate image signal lines (ISLa, ISLb, ISLc). For example, image data generated from camera module 1100a is provided to sub-image processor 1212a via image signal line ISLa, image data generated from camera module 1100b is provided to sub-image processor 1212b via image signal line ISLb, and image data generated from camera module 1100c is provided to sub-image processor 1212c via image signal line ISLc. Such image data transmission may be performed using, for example, but is not limited to, a Camera Serial Interface (CSI) based on MIPI (Mobile Industry Processor Interface).

[0144] Meanwhile, in one embodiment, one sub-image processor may be arranged to correspond to multiple camera modules. For example, sub-image processor 1212a and sub-image processor 1212c may not be implemented separately from each other as shown in the figure, but may be integrated into one sub-image processor, and image data provided from camera module 1100a and camera module 1100c may be selected through a selection element (e.g., a multiplexer) and then provided to the integrated sub-image processor.

[0145] The image data provided to each of the sub-image processors (1212a, 1212b, 1212c) is provided to an image generator 1214. The image generator 1214 generates an output image using the image data provided from each of the sub-image processors (1212a, 1212b, 1212c) according to image generating information or a mode signal.

[0146] Specifically, the image generator 1214 generates an output image by merging at least a portion of the image data generated from the camera modules 1100a, 1100b, and 1100c having different viewing angles according to the image generation information or mode signal. Also, the image generator 1214 selects one of the image data generated from the camera modules 1100a, 1100b, and 1100c having different viewing angles according to the image generation information or mode signal to generate an output image.

[0147] In one embodiment, the image generation information includes a zoom signal or zoom factor, and in one embodiment, the mode signal is based on a mode selected by a user, for example.

[0148] When the image generation information is a zoom signal (zoom factor) and each camera module (1100a, 1100b, 1100c) has a different field of view (viewing angle), the image generator 1214 performs different operations depending on the type of zoom signal. For example, when the zoom signal is a first signal, the image generator 1214 merges the image data output from camera module 1100a and the image data output from camera module 1100c, and generates an output image using the merged image signal and the image data output from camera module 1100b that was not used in the merging. When the zoom signal is a second signal different from the first signal, the image generator 1214 does not merge the image data, but instead selects one of the image data output from each camera module (1100a, 1100b, 1100c) to generate an output image. However, the present invention is not limited to this, and the method of processing image data can be modified as needed.

[0149] In one embodiment, the image generator 1214 receives multiple image data with different exposure times from at least one of the multiple sub-image processors (1212a, 1212b, 1212c) and performs HDR processing on the multiple image data to generate merged image data with an increased dynamic range.

[0150] The camera module controller 1216 provides control signals to each of the camera modules (1100a, 1100b, 1100c). The control signals generated by the camera module controller 1216 are provided to the corresponding camera modules (1100a, 1100b, 1100c) via separate control signal lines (CSLa, CSLb, CSLc).

[0151] One of the multiple camera modules (1100a, 1100b, 1100c) is designated as a master camera module (e.g., 1100b) by image generation information including a zoom signal or a mode signal, and the remaining camera modules (e.g., 1100a, 1100c) are designated as slave cameras. Such information is included in a control signal and provided to the corresponding camera modules (1100a, 1100b, 1100c) via separate control signal lines (CSLa, CSLb, CSLc).

[0152] The camera module operating as the master or slave is changed depending on the zoom factor or operation mode signal. For example, when the viewing angle of camera module 1100a is wider than that of camera module 1100b and the zoom factor indicates a low zoom magnification, camera module 1100b operates as the master and camera module 1100a operates as the slave. Conversely, when the zoom factor indicates a high zoom magnification, camera module 1100a operates as the master and camera module 1100b operates as the slave.

[0153] In one embodiment, the control signals provided from the camera module controller 1216 to each of the camera modules (1100a, 1100b, 1100c) include a sync enable signal. For example, if the camera module 1100b is the master camera and the camera modules (1100a, 1100c) are slave cameras, the camera module controller 1216 transmits a sync enable signal to the camera module 1100b. Upon receiving the sync enable signal, the camera module 1100b generates a sync signal based on the sync enable signal and provides the generated sync signal to the camera modules (1100a, 1100c) via a sync signal line SSL. The camera modules 1100b and the camera modules (1100a, 1100c) transmit image data to the application processor 1200 in synchronization with the sync signal.

[0154] In one embodiment, the control signals provided by the camera module controller 1216 to the camera modules (1100a, 1100b, 1100c) include mode information in the form of a mode signal, and based on the mode information, the camera modules (1100a, 1100b, 1100c) operate in a first operation mode or a second operation mode according to the sensing speed.

[0155] In a first operating mode, the multiple camera modules (1100a, 1100b, 1100c) generate image signals at a first rate (e.g., generate image signals at a first frame rate), encode them at a second rate higher than the first rate (e.g., encode image signals at a second frame rate higher than the first frame rate), and transmit the encoded image signals to the application processor 1200.

[0156] The application processor 1200 stores the received image signal, i.e., the encoded image signal, in an internal memory 1230 or an external memory 1400, and then reads and decodes the encoded image signal from the internal memory 1230 or the external memory 1400. The application processor 1200 then displays image data generated based on the decoded image signal. For example, a corresponding one of the sub-image processors 1212a, 1212b, and 1212c of the image processing device 1210 performs decoding and image processing on the decoded image signal.

[0157] In the second operating mode, the camera modules (1100a, 1100b, 1100c) generate image signals at a third rate lower than the first rate (e.g., generate image signals at a third frame rate lower than the first frame rate) and transmit the image signals to the application processor 1200. The image signals provided to the application processor 1200 are unencoded signals. The application processor 1200 performs image processing on the received image signals or stores the image signals in the internal memory 1230 or the external memory 1400.

[0158] The PMIC 1300 supplies power, e.g., a power supply voltage, to each of the multiple camera modules (1100a, 1100b, and 1100c). For example, under the control of the application processor 1200, the PMIC 1300 supplies a first power to the camera module 1100a via a power signal line PSLa, a second power to the camera module 1100b via a power signal line PSLb, and a third power to the camera module 1100c via a power signal line PSLc.

[0159] The PMIC 1300 generates power and adjusts the power levels corresponding to each of the camera modules (1100a, 1100b, 1100c) in response to a power control signal PCON from the application processor 1200. The power control signal PCON includes a power adjustment signal for each operation mode of the camera modules (1100a, 1100b, 1100c). For example, the operation mode may include a low power mode, and the power control signal PCON includes information about the camera module operating in the low power mode and the power level to be set. The power levels provided to each of the camera modules (1100a, 1100b, 1100c) may be the same or different. Furthermore, the power levels may be dynamically changed.

[0160] FIG. 15 is a block diagram showing the configuration of an image sensor according to one embodiment of the present invention.

[0161] Referring to FIG. 15, an image sensor 1500 includes a pixel array 1510, a controller 1530, a row driver 1520, and a pixel signal processing unit 1540.

[0162] The image sensor 1500 includes at least one of the image sensors (100A, 100B, 100C, 1142) described above. The pixel array 1510 includes a plurality of unit pixels arranged two-dimensionally, each of which includes a photoelectric conversion element. The photoelectric conversion element absorbs light to generate photocharges, and an electrical signal (output voltage) based on the generated photocharges is provided to the pixel signal processor 1540 via a vertical signal line.

[0163] The unit pixels included in the pixel array 1510 provide output voltages one at a time in rows, so that the unit pixels in one row of the pixel array 1510 are simultaneously activated by a select signal output from the row driver 1520. The unit pixels in the selected row provide output voltages corresponding to the absorbed light to the output lines of the corresponding columns.

[0164] The controller 1530 controls the row driver 1520 to cause the pixel array 1510 to absorb light and accumulate photocharges, or to temporarily store the accumulated photocharges and output electrical signals based on the stored photocharges to the outside of the pixel array 1510. The controller 1530 also controls the pixel signal processor 1540 to measure the output voltage provided by the pixel array 1510.

[0165] The pixel signal processing unit 1540 includes a correlated double sampler (CDS) 1542, an analog-to-digital converter (ADC) 1544, and a buffer 1546. The correlated double sampler 1542 samples and holds the output voltage provided by the pixel array 1510.

[0166] The correlated double sampler 1542 double samples a specific noise level and a level based on the generated output voltage, outputs a level corresponding to the difference, and receives the ramp signal generated by the ramp signal generator 1548, compares the two signals, and outputs the comparison result.

[0167] The analog-to-digital converter 1544 converts the analog signal corresponding to the level received from the correlated double sampler 1542 into a digital signal. The buffer 1546 latches the digital signal, and the latched signals are sequentially output to the outside of the image sensor 1500 and transmitted to an image processor (not shown).

[0168] FIG. 16 is a block diagram that schematically illustrates an electronic device including an image sensor according to one embodiment.

[0169] 16 , in a network environment ED00, an electronic device ED01 communicates with another electronic device ED02 via a first network ED98 (e.g., a short-range wireless communication network) or with another electronic device ED04 and / or a server ED08 via a second network ED99 (e.g., a long-range wireless communication network). The electronic device ED01 may communicate with the electronic device ED04 via the server ED08. The electronic device ED01 includes 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 subscriber identity module ED96, and / or an antenna module ED97. Some of these components (e.g., the display device ED60) may be omitted from the electronic device ED01, or other components may be added. Some of these components may be embodied as a single integrated circuit. For example, the sensor module ED76 (such as a fingerprint sensor, an iris sensor, or an illuminance sensor) may be embedded in the display device ED60 (such as a display).

[0170] The processor ED20 executes software (e.g., program ED40) to control one or more other components (e.g., hardware and software components) of the electronic device ED01 coupled to the processor ED20 and performs various data processing or calculations. As part of the data processing or calculations, the processor ED20 loads instructions and / or data received from other components (e.g., sensor module ED76, communication module ED90) into volatile memory ED32, processes the instructions and / or data stored in volatile memory ED32, and stores the resulting data in non-volatile memory ED34. The processor ED20 includes a main processor ED21 (e.g., central processing unit, application processor) and an auxiliary processor ED23 (e.g., graphics processing unit, image signal processor, sensor hub processor, communication processor), which can operate independently or together with the main processor ED21. The auxiliary processor ED23 consumes less power than the main processor ED21 and performs specialized functions.

[0171] The auxiliary processor ED23 controls the functions and / or states of some of the components of the electronic device ED01 (such as the display device ED60, the sensor module ED76, and the communication module ED90) in place of the main processor ED21 while the main processor ED21 is in an inactive state (sleep state), or together with the main processor ED21 while the main processor ED21 is in an active state (application execution state). The auxiliary processor ED23 (such as the image signal processor or the communication processor) may be embodied as part of other functionally related components (such as the camera module ED80 and the communication module ED90).

[0172] The memory ED30 stores various data required by the components of the electronic device ED01 (such as the processor ED20 and the sensor module ED76). The data includes, for example, software (such as the program ED40) and input and / or output data for instructions therefor. The memory ED30 includes a volatile memory ED32 and / or a non-volatile memory ED34. The non-volatile memory ED32 includes an internal memory ED36 fixedly mounted within the electronic device ED01 and a removable external memory ED38.

[0173] The program ED40 is stored as software in the memory ED30 and includes an operating system (OS) ED42, a middleware ED44, and / or an application ED46.

[0174] The input device ED50 receives instructions and / or data from outside the electronic device ED01 (e.g., a user) for use by components of the electronic device ED01 (e.g., the processor ED20). The input device ED50 includes a microphone, a mouse, a keyboard, and / or a digital pen (e.g., a stylus pen).

[0175] The audio output device ED55 outputs an audio signal to the outside of the electronic device ED01. The audio output device ED55 includes a speaker and / or a receiver. The speaker is used for general purposes such as multimedia playback or recording and playback, and the receiver is used to receive incoming calls. The receiver may be combined with a part of the speaker or may be implemented as a separate, independent device.

[0176] The display device ED60 visually presents information to the outside of the electronic device ED01. The display device ED60 includes a display, a holographic device, or a projector, and control circuitry for controlling the device. The display device ED60 includes touch circuitry configured to sense a touch and / or sensor circuitry (such as a pressure sensor) configured to measure the strength of a force generated by the touch.

[0177] The audio module ED70 converts sound into an electrical signal or vice versa, obtaining sound via the input device ED50 and outputting the sound through the speakers and / or headphones of the audio output device ED55 and / or other electronic devices (such as the electronic device ED02) directly or wirelessly coupled to the electronic device ED01.

[0178] The sensor module ED76 senses the operating state (power, temperature, etc.) of the electronic device ED01 or the external environmental state (user state, etc.) and generates an electrical signal and / or a data value corresponding to the sensed state. The sensor module ED76 includes a gesture sensor, a gyro sensor, a barometric pressure sensor, a magnetic sensor, an acceleration sensor, a grip sensor, a proximity sensor, a color sensor, an IR (Infrared) sensor, a biosensor, a temperature sensor, a humidity sensor, and / or an illuminance sensor.

[0179] The interface ED77 supports one or more specified protocols used for the electronic device ED01 to be directly or wirelessly coupled to other electronic devices (such as the electronic device ED02.) The interface ED77 includes a High Definition Multimedia Interface (HDMI), a Universal Serial Bus (USB), an SD Card interface, and / or an audio interface.

[0180] The connection terminal ED78 includes a connector that physically connects the electronic device ED01 to another electronic device (such as the electronic device ED02). The connection terminal ED78 includes an HDMI (registered trademark) connector, a USB connector, an SD card (registered trademark) connector, and / or an audio connector (such as a headphone connector).

[0181] The haptic module ED79 converts electrical signals into mechanical stimuli (such as vibrations or movements) or electrical stimuli that the user perceives through touch or kinesthetic sensation. The haptic module ED79 includes motors, piezoelectric elements, and / or electrical stimulators.

[0182] Camera module ED80 captures still and moving images. Camera module ED80 includes a lens assembly including one or more lenses, image sensor 100 of FIG. 1, an image signal processor, and / or a flash. The lens assembly included in camera module ED80 collects light emitted from a subject from which an image is to be captured.

[0183] The power management module ED88 manages the power supplied to the electronic device ED01. The power management module ED88 may be embodied as part of a PMIC (Power Management Integrated Circuit).

[0184] The battery ED89 provides power to the components of the electronic device ED01. The battery ED89 includes a non-rechargeable primary battery, a rechargeable secondary battery, and / or a fuel cell.

[0185] The communication module ED90 supports the establishment of a direct (wired) communication channel and / or a wireless communication channel between the electronic device ED01 and other electronic devices (such as the electronic device ED02, the electronic device ED04, and the server ED08) and the execution of communication via the established communication channel. The communication module ED90 includes one or more communication processors that operate independently of the processor ED20 (such as an application processor) and support the direct communication and / or the wireless communication. The communication module ED90 includes a wireless communication module ED92 (such as a cellular communication module, a short-range wireless communication module, or a GNSS (Global Navigation Satellite System) communication module) and / or a wired communication module ED94 (such as a LAN (Local Area Network) communication module, a power line communication module, etc.). The corresponding one of these communication modules communicates with other electronic devices via a first network ED98 (a short-range communication network such as Bluetooth, WiFi Direct, or IrDA (Infrared Data Association)) or a second network ED99 (a long-range communication network such as a cellular network, the Internet, or a computer network (LAN, WAN, etc.)). Such various types of communication modules may be integrated into one component (e.g., a single chip) or embodied by separate components (multiple chips). The wireless communication module ED92 identifies and authenticates the electronic device ED01 within a communication network such as the first network ED98 and / or the second network ED99 using subscriber information (e.g., an International Mobile Subscriber Identity (IMSI)) stored in the subscriber identity module ED96.

[0186] The antenna module ED97 transmits or receives signals and / or power to or from the outside (such as other electronic devices). The antenna includes a radiator made of a conductive pattern formed on a substrate (such as a PCB). The antenna module ED97 includes one or more antennas. When multiple antennas are included, the communication module ED90 selects an antenna from the multiple antennas that is suitable for a communication method used in a communication network such as the first network ED98 and / or the second network ED99. Signals and / or power are transmitted or received between the communication module ED90 and other electronic devices through the selected antenna. In addition to the antenna, other components (such as an RFIC) may be included as part of the antenna module ED97.

[0187] Some of the components are connected to each other via a peripheral communication method (bus, GPIO (General Purpose Input and Output), SPI (Serial Peripheral Interface), MIPI (Mobile Industry Processor Interface), etc.) to exchange signals (commands, data, etc.).

[0188] Commands or data are transmitted or received between the electronic device ED01 and an external electronic device ED04 via a server ED08 connected to a second network ED99. The other electronic devices (ED02, ED04) may be the same or different types of devices as the electronic device ED01. All or part of the operations performed by the electronic device ED01 may be performed by one or more of the other electronic devices (ED02, ED04, ED08). For example, when the electronic device ED01 needs to perform a certain function or service, instead of performing the function or service itself, it requests one or more other electronic devices to perform the function or service in whole or in part. The one or more other electronic devices that receive the request perform the additional function or service related to the request and transmit the results of their execution to the electronic device ED01. For this purpose, cloud computing, distributed computing, and / or client-server computing technologies are used.

[0189] FIG. 17 is a block diagram schematically illustrating the camera module of FIG.

[0190] Referring to FIG. 17 , the camera module ED80 includes a lens assembly CM10, a flash CM20, an image sensor 100 (such as the image sensor 100 of FIG. 1 ), an image stabilizer CM40, a memory CM50 (such as a buffer memory), and / or an image signal processor CM60. The lens assembly CM10 collects light emitted from a subject to be imaged. The camera module ED80 may include multiple lens assemblies CM10, in which case the camera module ED80 functions as a dual camera, a 360° camera, or a spherical camera. Some of the multiple lens assemblies CM10 may have the same lens attributes (such as angle of view, focal length, autofocus, F-number, optical zoom, etc.) or may have different lens attributes. The lens assembly CM10 may include a wide-angle lens or a telephoto lens.

[0191] The flash CM 20 emits light used to enhance light emitted or reflected from a subject. The flash CM 20 includes one or more light-emitting diodes (e.g., RGB (Red-Green-Blue) LEDs), white LEDs, infrared LEDs, and ultraviolet LEDs) and / or xenon lamps. The image sensor 100 is the image sensor described in FIG. 1 and captures an image corresponding to the subject by converting light emitted from or reflected from the subject and transmitted through the lens assembly CM10 into an electrical signal. The image sensor 100 includes one or more sensors selected from image sensors with different attributes, such as an RGB sensor, a BW (Black and White) sensor, an IR sensor, or a UV sensor. Each sensor included in the image sensor 100 is implemented as a charged coupled device (CCD) sensor and / or a complementary metal oxide semiconductor (CMOS) sensor.

[0192] The image stabilizer CM40 responds to movement of the camera module ED80 or the electronic device M01 including it by moving one or more lenses included in the lens assembly CM10 or the image sensor 100 in a specific direction or by controlling the operating characteristics of the image sensor 100 (such as adjusting the read-out timing) to compensate for the negative effects of the movement. The image stabilizer CM40 senses the movement of the camera module ED80 or the electronic device ED01 using a gyro sensor (not shown) or an acceleration sensor (not shown) arranged inside or outside the camera module ED80. The image stabilizer CM40 is embodied optically.

[0193] The memory CM50 stores all or part of the data of an image acquired via the image sensor 100 for subsequent image processing. For example, when multiple images are acquired at high speed, the acquired original data (Bayer-Patterned data, high-resolution data, etc.) is stored in the memory CM50, and after displaying only the low-resolution image, the original data of the selected (e.g., user-selected) image is transmitted to the image signal processor CM60. The memory CM50 may be integrated into the memory ED30 of the electronic device ED01, or may be configured as a separate memory operated independently.

[0194] The image signal processor CM60 performs image processing on images acquired via the image sensor 100 or image data stored in the memory CM50. Image processing includes depth map generation, 3D modeling, panorama generation, feature point extraction, image synthesis, and / or image compensation (noise reduction, resolution adjustment, brightness adjustment, blurring, sharpening, softening, etc.). The image signal processor CM60 controls (exposure time control, readout timing control, etc.) the components included in the camera module ED80 (e.g., the image sensor 100). Images processed by the image signal processor CM60 are stored back in the memory CM50 for further processing or provided to external components of the camera module ED80 (e.g., the memory ED30, the display device ED60, the electronic device ED02, the electronic device ED04, the server ED08, etc.). The image signal processor CM60 may be integrated into the processor ED20 or may be a separate processor operating independently of the processor ED20. When the image signal processor CM60 is composed of the processor ED20 and a separate processor, the image processed by the image signal processor CM60 is displayed on the display device ED60 after undergoing further image processing by the processor ED20.

[0195] The electronic device ED01 may include multiple camera modules ED80, each having different attributes or functions. In such a case, one of the multiple camera modules ED80 is a wide-angle camera and another is a telephoto camera. Similarly, one of the multiple camera modules ED80 is a front camera and another is a rear camera.

[0196] Although the embodiments of the present invention have been described in detail above with reference to the drawings, the present invention is not limited to the above-described embodiments and can be modified in various ways without departing from the technical concept of the present invention. [Explanation of symbols]

[0197] 10, 1510 pixel array 20 Column Driver 30, 1520 Row Driver 40 Timing Controller 50 Readout circuit 70 Image Processor 100, 100a, 100b, 100c, 1142, 1500 image sensors 110 Sensor board 110S Top surface of sensor board 111, 112, 113, 114 1st to 4th pixels 120 Lower anti-reflection layer 121, 122 First and second lower antireflection layers 130a, 130b First and second color filters 131 Color Filter Fence 131a Insulating film 140 spacer 151, 152 First and second meta-microlens arrays 151a, 151b, 151c, 151d 1st to 4th lenses 151u top 160, 160a, 160b, 160c, 160d, 160e, 160f, 160g, 160h, 160i, 160j, 160k, 160l Top anti-reflection layer 160r Underside of upper anti-reflection layer 160u Top surface of the upper anti-reflection layer 161, 161a, 161b, 161c, 161d, 161e, 161f, 161g, 161h, 161i, 161j, 161k, 161l 1st upper antireflection layer 161ah, 161bh, 161ch, 161dh, 161fh, 161gh, 161jh hall 161u Upper surface of first upper anti-reflection layer 162, 162a, 162b, 162c, 162d, 162e, 162f, 162g, 162h, 162i, 162j, 162k, 162l 2nd top anti-reflection layer 162bh, 162ch, 162eh, 162fh, 162gh, 162hh, 162ih, 162jh, 162kh holes 163, 163a, 163b, 163c, 163d, 163e, 163f, 163g, 163h Third upper anti-reflection layer 163ch, 163fh, 163gh, 163hh, 163jh, 163kh, 163lh holes 163r Lower surface of third upper anti-reflection layer 164 4th upper anti-reflection layer 1000 electronic devices 1100 Camera Module Group 1100a, 1100b, 1100c camera modules 1105 Prism 1106 Center axis 1107 Reflective surface 1110 Optical Path Folding Element (OPFE) 1130 Actuator 1140 Image sensing device 1144 Control Logic 1146 memory 1147 Calibration Data 1150 Storage 1200 Application Processor 1210 Image Processing Device 1212a, 1212b, 1212c Sub-Image Processors 1214 Image Generator 1216 Camera Module Controller 1220 memory controller 1230 internal memory 1300 PMIC (Power Management IC) 1400 external memory 1530 Controller 1540 pixel signal processing unit 1542 Correlated Double Sampler (CDS) 1544 Analog-to-Digital Converter (ADC) 1546 buffers 1548 Ramp Signal Generator CM10 Lens Assembly CM20 Flash CM40 Image Stabilizer CM50, ED30 memory CM60 Image Signal Processor CSLa, CSLb, CSLc control signal lines DL1, DL2 First and second dielectric layers ED00 Network environment ED01, ED02, ED04 Electronic equipment ED08 Server ED20 processor ED21 main processor ED23 auxiliary processor ED32 Volatile Memory ED34 Non-volatile Memory ED36 built-in memory ED38 external memory ED40 Program ED42 Operational System (OS: Operating System) ED44 Middleware ED46 Application ED50 Input Device ED55 audio output device ED60 display device ED70 Audio Module ED76 Sensor Module ED77 interface ED78 connecting terminal ED79 Haptic Module ED80 Camera Module ED88 Power Management Module ED89 Battery ED90 Communication Module ED92 Wireless Communication Module ED94 Wired Communication Module ED96 Subscriber Identity Module ED97 Antenna Module ED98 1st Network ED99 Second Network ES1, ES2 First and second etch stoppers ISLa, ISLb, ISLc image signal lines NP1, NP2 First and second nanoposts PCON Power Control Signal PSLa, PSLb, PSLc Power Signal Lines PXU Pixel Unit SSL Sync Signal Line

Claims

1. a sensor substrate including a plurality of first pixels that sense light of a first wavelength and a plurality of second pixels that sense light of a second wavelength different from the first wavelength; a first color filter and a second color filter disposed on the sensor substrate and corresponding to the first pixel and the second pixel, respectively; a transparent spacer disposed on the first color filter and the second color filter; at least one meta-microlens array disposed on the spacer and including a plurality of nanoposts (NPs) arranged to focus incident light onto the plurality of first pixels and the plurality of second pixels; and at least two or more upper anti-reflection layers disposed on the light-entering surface of the meta-microlens array; The image sensor is characterized in that the plurality of upper anti-reflection layers are stacked so as to overlap each other in the vertical direction, and each refractive index increases toward the meta-microlens array.

2. The image sensor of claim 1 , wherein the refractive index of the plurality of upper anti-reflection layers is smaller than the refractive index of the meta-microlens and larger than the refractive index of air.

3. 2. The image sensor of claim 1, wherein the refractive index of each of the plurality of upper anti-reflection layers increases linearly by 0.2 for every 100 nm of thickness of each of the plurality of upper anti-reflection layers in the vertical direction.

4. At least one of the plurality of upper antireflection layers includes a plurality of holes that are periodically arranged in two dimensions, The image sensor of claim 1 , wherein the hole is exposed to the outside.

5. The image sensor of claim 4 , wherein a cross-sectional area of ​​each of the plurality of holes in a horizontal direction is tapered so as to become smaller as it approaches the meta-microlens array.

6. a third upper anti-reflection layer disposed at the bottom of the plurality of upper anti-reflection layers includes a plurality of holes periodically arranged two-dimensionally; a second upper antireflection layer disposed on the third upper antireflection layer among the plurality of upper antireflection layers covers an outer surface of the third upper antireflection layer; 2. The image sensor of claim 1, wherein a first upper anti-reflection layer disposed on the second upper anti-reflection layer among the plurality of upper anti-reflection layers covers an outer surface of the second upper anti-reflection layer.

7. The image sensor of claim 6 , wherein the cross-sectional area of ​​the third upper anti-reflection layer in the horizontal direction increases as it approaches the meta-microlens array.

8. 7. The image sensor of claim 6, wherein at least one of the second upper anti-reflection layer and the first upper anti-reflection layer has a top surface with a constant vertical level.

9. 2. The image sensor of claim 1, wherein each of the plurality of upper anti-reflection layers has a thickness of 100 Å to 2000 Å.

10. 2. The image sensor of claim 1, further comprising an etch stopper disposed between the spacer and the meta-microlens array.

Images