KR102614907B1 - Image sensor and method to produce image sensor - Google Patents

Abstract

An image sensor and a method of manufacturing the image sensor are provided. The image sensor may include a block layer including an absorption layer and a transparent layer, a lens element disposed at the bottom of the block layer, and a sensing element disposed to face the lens element.

Description

Image sensor and image sensor manufacturing method {IMAGE SENSOR AND METHOD TO PRODUCE IMAGE SENSOR}

Hereinafter, technology related to an image sensor and its manufacturing method is provided.

An image sensor is a device for capturing an image of a subject, and can convert an optical signal containing image information of the subject into an electrical signal. Image sensors may be included in various electronic devices, and for example, charge coupled device (CCD) image sensors and complementary metal oxide semiconductor (CMOS) image sensors are widely used.

A CMOS image sensor includes a plurality of pixels including a photoelectric conversion element and a plurality of transistors. The signal photoelectrically converted by the photoelectric conversion element is processed and output by a plurality of transistors, and image data can be generated based on the pixel signal output from the pixel. Each pixel can photoelectrically convert light of a specific color or wavelength range and output a signal accordingly.

An image sensor according to an embodiment includes a block layer that includes an absorbing layer and a transparent layer and allows light received from the outside to pass through openings formed in the absorbing layer and the transparent layer; And it may include a lens element that transmits the light to a sensing element.

The sensing element is spaced apart from the lens element and may receive light passing through the opening and the lens element.

The lens element may refract the light to form a focal point on the sensing element.

The block layer may be spaced apart from the sensing element by the focal length of the lens element.

The image sensor may further include a transparent substrate that allows light to pass through.

The opening may be formed to be aligned with the placement of the lens element in the block layer.

The image sensor may further include a spacer that maintains a gap between the block layer and the sensing element.

The block layer may form the opening by a structure in which the absorbing layer and the transparent layer are alternately arranged.

Depending on the arrangement of the lens elements, the absorption layer may include an aperture formed as a circular area centered on a point in the absorption layer corresponding to the lens element.

The absorption layer may include an aperture having a first diameter formed around a point corresponding to the lens element, and the block layer may further include another absorption layer having an aperture having a second diameter different from the first diameter. there is.

In the block layer, the diameter of the opening may gradually vary from one side of the block layer to the other side.

The transparent layer can transmit light in a predetermined wavelength band.

The block layer may have a height determined based on a predetermined viewing angle.

The block layer may be a stack of a determined number of absorption layers based on a predetermined viewing angle.

The block layer may have an opening diameter determined based on a predetermined amount of light and may be spaced apart from the sensing element by a focal distance determined based on the predetermined amount of light.

The transparent layer may include a transparent polymer that allows light to pass through.

The absorption layer may include a black matrix material that absorbs light.

A circular aperture formed in each of the plurality of absorption layers included in the block layer may have a diameter determined based on a predetermined viewing angle and a refractive index determined by the transparent substrate and the transparent layer.

The lens element and the sensing element may be arranged in a planar array pattern, and the absorption layer may include an aperture formed in alignment with the planar array pattern.

A method of manufacturing an image sensor according to an embodiment includes providing a transparent substrate; providing a block layer comprising an absorbent layer and a transparent layer; It may include providing a lens element according to a pattern in which an opening is formed in the block layer.

1 is a diagram illustrating the configuration of an image sensor according to an embodiment.
FIG. 2 is a diagram illustrating a block layer and a lens element according to an embodiment.
FIG. 3 is a diagram illustrating a cross section of a block layer and a lens element according to an embodiment.
Figure 4 is a diagram explaining the viewing angle of an image sensor according to an embodiment.
FIG. 5 is a diagram illustrating a viewing angle determined by an opening of a block layer according to an embodiment.
FIG. 6 is a diagram illustrating a viewing angle determined by an opening of a block layer according to another embodiment.
Figure 7 is a flowchart explaining a method of manufacturing an image sensor according to an embodiment.
Figure 8 is a diagram explaining a method of providing a block layer according to an embodiment.
Figure 9 is a diagram explaining a method of providing a lens element according to an embodiment.
Figure 10 shows an image taken with a scanning electron microscope of a structure in which lens elements are integrated on one side of a block layer according to an embodiment.
Figure 11 shows an image taken with an optical microscope of a structure in which lens elements are integrated on one side of a block layer according to an embodiment.
FIG. 12 is a diagram showing light transmittance according to the number of absorption layers included in a block layer according to an embodiment.
FIG. 13 shows images of the top and side surfaces of an image sensor according to an embodiment taken using a confocal laser scanning microscope.
FIG. 14 is a diagram illustrating an intensity profile of an image sensor according to an embodiment.
Figure 15 shows an image captured through an image sensor according to one embodiment.
Figure 16 shows the results of measuring the viewing angle of an image sensor according to one embodiment.
Figures 17 and 18 are diagrams illustrating the effect of a block layer on a modulation transfer function (MTF) according to an embodiment.

Hereinafter, embodiments will be described in detail with reference to the attached drawings. However, the scope of the patent application is not limited or limited by these examples. The same reference numerals in each drawing indicate the same members.

Various changes may be made to the embodiments described below. The embodiments described below are not intended to limit the embodiments, but should be understood to include all changes, equivalents, and substitutes therefor.

Terms used in the examples are merely used to describe specific examples and are not intended to limit the examples. Singular expressions include plural expressions unless the context clearly dictates otherwise. In this specification, terms such as “comprise” or “have” are intended to designate the presence of features, numbers, steps, operations, components, parts, or combinations thereof described in the specification, but are not intended to indicate the presence of one or more other features. It should be understood that this does not exclude in advance the possibility of the existence or addition of elements, numbers, steps, operations, components, parts, or combinations thereof.

Unless otherwise defined, all terms used herein, including technical or scientific terms, have the same meaning as generally understood by a person of ordinary skill in the technical field to which the embodiments belong. Terms defined in commonly used dictionaries should be interpreted as having a meaning consistent with the meaning in the context of the related technology, and unless explicitly defined in the present application, should not be interpreted in an ideal or excessively formal sense. No.

In addition, when describing with reference to the accompanying drawings, identical components will be assigned the same reference numerals regardless of the reference numerals, and overlapping descriptions thereof will be omitted. In describing the embodiments, if it is determined that detailed descriptions of related known technologies may unnecessarily obscure the gist of the embodiments, the detailed descriptions are omitted.

1 is a diagram illustrating the configuration of an image sensor according to an embodiment.

The image sensor 100 may represent a device for capturing an image of a subject. According to one embodiment, the image sensor 100 may include a lens element 110, a block layer 120, a transparent substrate 130, a sensing element 140, a spacer 150, and a camera chip 190. there is.

The lens element 110 is an element that refracts light received from the outside and can concentrate light. The lens element 110 may refract light to form a focal point on the sensing element 140. For example, one side of the lens element 110 may have a protruding portion, and the other side may be a flat side. For example, the lens element 110 may be a micro lens having a convex shape on one side, but is not limited thereto. One surface having a protruding portion of the lens element 110 may be formed in a spherical shape, an aspherical shape, or a Fresnel shape. However, it is not limited to this, and the lens element 110 may be implemented as a concave lens.

A set of lens elements 110 may be referred to as a lens array. For example, a lens array may include a plurality of lens elements arranged along a planar array pattern (eg, a grid pattern).

The block layer 120 may represent a layer that blocks light. The block layer 120 may include a transparent layer and an absorption layer on which a pattern (eg, a hole pattern) is formed. The block layer 120 may include an aperture formed by a pattern of the absorption layer. The block layer 120 can transmit light received from the outside to the lens element 110 only through the opening. The absorbing layer and transparent layer included in the block layer 120 will be described in detail in FIGS. 2 and 3 below.

The transparent substrate 130 may represent a transparent substrate that allows light to pass through. The transparent substrate 130 may be disposed on top of the block layer 120. However, the arrangement of the transparent substrate 130 is not limited to this, and the transparent substrate 130 may be disposed on the lens element 110 disposed on the block layer 120. For example, the transparent substrate 130 may include a glass wafer, but the type of the transparent substrate 130 is not limited to this.

The sensing element 140 is spaced apart from the lens element 110 and can receive light passing through the opening of the block layer 120 and the lens element 110. The sensing element 140 may receive light passing through the opening of the transparent substrate 130 and the block layer 120 and condensed by the lens element 110. The sensing element 140 may output a signal indicating the intensity of the received light. For example, the sensing element 140 may sense light corresponding to an arbitrary color channel and output a signal indicating the intensity of the corresponding color. The color channel is a channel representing a color corresponding to a portion of the visible region and may include, for example, a red channel, a green channel, and a blue channel. The individual sensing element 140 may sense light corresponding to one color channel among the red channel, green channel, and blue channel. However, the wavelength that the sensing element 140 can sense is not limited to this, and depending on the design, the sensing element 140 can also sense infrared or ultraviolet rays.

The set of sensing elements 140 may be referred to as a sensor array. For example, the sensor array may include a plurality of sensing elements arranged along a planar array pattern (e.g., a grid pattern, etc.). there is. The sensor array may include a sensing element 140 for sensing red, a sensing element 140 for sensing green, and a sensing element 140 for sensing blue, and the sensor array can distinguish and sense three colors. You can.

The spacer 150 may maintain the gap between the block layer 120 and the sensing element 140. For example, the spacer 150 may support the block layer 120 and the sensing element 140. In FIG. 1 , the spacer 150 is shown as being disposed along the outer boundary of the sensor array, and the spacer 150 may support the outer boundary of the block layer 120.

The camera chip 190 may represent a chip on which a sensor array is implemented. The camera chip 190 may be implemented at, for example, a wafer level.

According to one embodiment, the lens element 110, block layer 120, transparent substrate 130, sensing element 140, spacer 150, and camera chip 190 are manufactured through an integration process. can be combined

FIG. 2 is a diagram illustrating a block layer and a lens element according to an embodiment.

The block layer 220 may include an absorption layer 221 and a transparent layer 222. The block layer 220 may pass light received from the outside through the opening 229 formed in the absorption layer 221 and the transparent layer 222. For example, the block layer 220 may provide light received from the outside through the opening 229 to the lens element 210.

The absorption layer 221 is a layer that absorbs light, and may also be referred to as, for example, a photo absorption layer. The absorption layer 221 may include a black matrix material that absorbs light. The black matrix material may include, for example, Black SU-8. However, the material of the absorption layer 221 is not limited to this, and the absorption layer 221 may include a negative photoresist that absorbs light. Depending on the arrangement of the lens element 210, the absorption layer 221 may include an aperture formed as a circular area centered on a point corresponding to the lens element 210 in the absorption layer 221. The absorption layer 221 may include an aperture formed in alignment with a planar array pattern.

The transparent layer 222 may represent a layer that allows light to pass through. The transparent layer 222 may include a transparent polymer that allows light to pass through. Transparent polymers may include, for example, SU-8. However, the material of the transparent layer 222 is not limited to this, and the transparent layer 222 may include a negative photoresist that allows light to pass through. As another example, the transparent layer 222 may transmit light in a predetermined wavelength band. For example, the transparent layer 222 may transmit only light in the visible light band.

The block layer 220 may form an aperture 229 by having an absorption layer 221 and a transparent layer 222 alternately arranged. In the block layer 220, the layer corresponding to the surface opposite to the surface on which the lens element 210 is disposed may be the absorption layer 221. However, the arrangement of the absorption layer 221 is not limited to this, and the absorption layer 221 may be arranged on the same surface as the lens element 210.

A circular aperture may be formed in the absorption layer 221 along a grid pattern. For example, when the block layer 220 includes a plurality of absorption layers, apertures of the plurality of absorption layers may form the opening 229 . The opening 229 may represent a portion of the block layer 220 that allows light to pass through. The opening 229 may be formed to be aligned with the arrangement of the lens element 210 in the block layer 220. The opening 229 is explained in FIG. 3 below.

The lens element 210 may transmit light received from the outside to the sensing element. For example, the lens element 210 is disposed below the block layer 220 and may pass light provided from the opening 229. The lens element 210 may have a protrusion on one surface of the lens element 210, and may be arranged so that the protrusion faces the sensing element. For example, the lens element 210 may transmit light provided from the opening 229 to the sensing element corresponding to the opening 229. However, the above-described structure is a simple example and is not limited thereto. For example, the lens element 210 is not limited to being disposed at the bottom of the block layer 220, and the lens element 210 is disposed at the top of the block layer 220, or at both the top and bottom. It could be. Additionally, instead of the protruding portion of the lens element 210 facing the sensing element, the flat portion may be disposed to face the sensing element. The lens element 210 may have a concave portion instead of a protruding portion on one surface.

A pattern (e.g., a hole pattern) formed on the block layer 220 according to one embodiment transmits light passing through an arbitrary opening 229 in the block layer 220 to a sensing element corresponding to the opening 229. and can prevent the light from being directed to other sensing elements. Therefore, the block layer 220 having the above-described hole pattern can reduce optical crosstalk. Additionally, the wide viewing angle of the image sensor may be designed depending on the diameter of the hole pattern and the height of the block layer 220.

FIG. 3 is a diagram illustrating a cross section of a block layer and a lens element according to an embodiment.

The image sensor according to one embodiment may include a block layer 320 in which an opening 329 is formed and a lens element 310 disposed below the block layer 320. As shown in FIG. 3, the block layer 320 may have a structure in which absorption layers 321 and transparent layers 322 are alternately stacked. The individual absorption layer 321 may include a circular aperture, and the circular aperture may be filled with the same material as the transparent layer 322.

In the absorption layer 321, the area where the aperture is formed can transmit light, and the remaining area where the aperture is not formed can absorb light. Light passing through the aperture of any absorption layer 321 may pass through the next transparent layer 322. Light that has passed through the next transparent layer 322 may pass through the aperture of the next absorption layer. Accordingly, the aperture of each of the plurality of absorption layers may form a cylindrical opening 329 that passes light received from the outside.

Light passing through the opening 329 may be provided to the lens element 310. The lens element 310 may concentrate the light passing through the opening 329 and transmit it to the sensing element.

Figure 4 is a diagram explaining the viewing angle of an image sensor according to an embodiment.

The block layer 420 may have a height (H) determined based on a predetermined viewing angle. For example, the viewing angle of the image sensor is the maximum angle of incidence on the transparent substrate 430 at which light received from the outside can reach the sensing element. can indicate. Light incident on the transparent substrate 430 may be refracted according to the refractive index of the transparent substrate 430 and the transparent layer 422. For example, in Figure 4, light is transmitted to the transparent substrate 430. It can be assumed that the incident occurs at an angle of . Since the absorption layer 421 absorbs light in the block layer 420, the maximum angle at which light can pass through the block layer 420 through the opening is can be decided. For example, the maximum angle at which light received from the outside can pass through the block layer 420. may be determined according to the diameter of the opening formed in the block layer 420 and the height of the opening. The height of the opening may correspond to the height (H) of the block layer 420.

For example, in an image sensor, the height (H) of the block layer 420, , and The relationship can be expressed as Table 1 below.

H ( ) 120 22.61 33.92 110 24.44 36.66 100 26.56 39.84 90 29.054 43.58 80 32.00 48.00 70 35.53 53.30 60 39.80 59.70 50 45 67.5 40 51.340 77.01 30 59.036 88.55 20 68.198 77.7

For example, according to Table 1, when the height (H) of the block layer 420 is 110 μm, the viewing angle of the image sensor may appear to be about 70°. However, the configuration of the block layer 420 is as described above. It is not limited. The block layer 420 may be formed by stacking a number of absorption layers 421 determined based on a predetermined viewing angle. For example, the height of the block layer 420 may be determined based on a predetermined viewing angle, and the number of absorption layers 421 stacked may be determined according to the height of the block layer 420 and the gap between the absorption layers 421. . The gap between the absorption layers 421 may correspond to the thickness of the transparent layer 422.

FIG. 5 is a diagram illustrating a viewing angle determined by an opening of a block layer according to an embodiment.

The absorption layer 521 may include an aperture with a first diameter D1 formed around a point corresponding to the lens element 510. The block layer 520 may further include another absorption layer 522 with an aperture having a second diameter D2 different from the first diameter D1. Another absorption layer 523 may include an aperture with a third diameter D3 that is different from the second diameter D2. The first diameter (D1), the second diameter (D2), and the third diameter (D3) may have values that gradually increase or decrease. For example, the block layer 520 may have a structure in which the diameter of the opening 529 gradually changes from one side of the block layer 520 to the other side.

Figure 4 shows an example in which the diameter of the opening 529 is constant, but Figure 5 shows an example in which the diameter of the opening 529 increases. In FIG. 5 , the diameter of the aperture formed in each absorption layer may gradually increase from the absorption layer closest to the lens element 510 to the absorption layer farthest from the lens element 510 . When the diameter of the opening 529 gradually increases, the maximum angle at which light can pass through the block layer 520 by the opening 529 may increase. Here, the degree to which the diameter of the opening 529 increases is determined by the refractive index of the transparent substrate 530 and the transparent layer and the desired viewing angle. It may be determined based on (hereinafter, a predetermined viewing angle). predetermined viewing angle After the light incident on the transparent substrate 530 is refracted, the degree to which the diameter of the opening 529 increases can be determined according to the angle at which the light enters the block layer 520. The degree to which the diameter of the opening 529 increases is the maximum angle that can pass through the block layer 520. can respond. Therefore, the circular aperture formed in each of the plurality of absorption layers included in the block layer 520 has a refractive index determined by the transparent substrate 530 and the transparent layer and a predetermined viewing angle. It may have a diameter determined based on .

Additionally, the block layer 520 may be spaced apart from the sensing element 540 by the focal length of the lens element 510. For example, the block layer 520 may be disposed on the opposite side of the sensing element 540 with respect to the lens element 510, as shown in FIG. 5 . However, the arrangement of the block layer 520 is not limited to this, and the block layer 520 may be arranged on the same side as the sensing element 540 with respect to the lens element 510.

For example, the block layer 520 may have an opening diameter determined based on a predetermined amount of light and may be spaced apart from the sensing element 540 by a focal distance determined based on the predetermined amount of light.

Figure 5 shows an example in which the diameter of the opening 529 gradually increases, but Figure 6 below explains the opposite example.

FIG. 6 is a diagram illustrating a viewing angle determined by an opening of a block layer according to another embodiment.

The block layer 620 includes, based on the lens element 610, a first absorption layer 621 including an aperture with a first diameter D1, and a second absorption layer 622 including an aperture with a second diameter D2. ), and a third absorption layer 623 including an aperture of a third diameter. The first diameter (D1), the second diameter (D2), and the third diameter (D3) may gradually decrease. For example, the block layer 620 may have a structure in which the diameter of the opening 629 gradually decreases from one side of the block layer 620 to the other side. Through a structure in which the diameter of the opening 629 gradually decreases, the image sensor can better observe distant objects.

Figure 7 is a flowchart explaining a method of manufacturing an image sensor according to an embodiment.

According to one embodiment, the image sensor may be stacked in the order of a transparent substrate, a block layer, a lens element, and a sensing element.

First, in step 710 a transparent substrate may be provided. As described above, the transparent substrate may be a glass wafer, but is not limited thereto.

And in step 720, a block layer including an absorbing layer and a transparent layer may be provided. For example, the block layer can be provided on a transparent substrate. As described above, the absorbing layer and the transparent layer can be alternately stacked, and the formation of such a block layer is explained in FIG. 8 below.

Subsequently, in step 730, a lens element may be provided according to a pattern in which an opening is formed in the block layer. For example, lens elements may be provided on a block layer. FIG. 9 below explains a method of providing a micro lens array as a lens element.

Figure 8 is a diagram explaining a method of providing a block layer according to an embodiment.

First, an absorbing layer may be provided on a transparent substrate in step 821. For example, a black polymer (eg, Black SU-8) may be coated as an absorbent layer.

And in step 822, a mask may be aligned on the absorption layer. The mask may be placed in a planar array pattern on the absorbent layer. For example, a circular mask may be placed along a grid pattern. With the mask lined up on the absorption layer, ultraviolet rays may be emitted. The part of the absorption layer excluding the mask may be exposed to ultraviolet rays. The absorber layer may be composed of negative photoresist. Photoresists can represent light-sensitive materials used in several processes and can form a patterned coating on a surface.

Then, in step 823, the absorber layer patterned by exposure to ultraviolet rays may be developed by a developer. A solvent called a developer may be applied to the surface. In negative photoresist, areas exposed to ultraviolet light may become insoluble in the developer. Unexposed portions of negative photoresist can be dissolved by photoresist developer. Accordingly, as shown in FIG. 8, portions of the absorption layer corresponding to the mask shape can be dissolved and removed.

And in step 824, a transparent layer may be coated on the patterned absorber layer. With the transparent layer coated, the block layer can be exposed to ultraviolet light. The transparent layer may also be composed of negative photoresist, and the portion exposed to ultraviolet light may be insoluble in the developer. Because it was exposed to ultraviolet rays without a mask, the entire coated transparent layer could be fixed.

A hydrophile process may then be applied to the transparent layer in step 825. Through hydrophilic treatment, the bonding force between the transparent layer and the absorbent layer can be increased. Hydrophilic treatment may be, for example, oxygen plasma treatment.

And in step 826, a plurality of layers (eg, N layers) may be stacked by repeating the steps 821 to 825 described above. Here, N may be an integer of 2 or more. Absorbent layers and transparent layers may be alternately laminated. While the above-described steps 821 to 825 are repeated, alignment can be maintained between the patterns formed in each of the absorption layers. Accordingly, a set of apertures formed in individual absorbing layers may correspond to an opening.

Figure 9 is a diagram explaining a method of providing a lens element according to an embodiment.

First, in step 931, a thermoplastic polymer may be provided on the block layer. Thermoplastic polymer is a transparent material for manufacturing lenses and can represent a material that can be deformed by heat. For example, the thermoplastic polymer may represent AZ9260.

Then, in step 932, a mask with a pattern aligned with respect to the planar array pattern formed on the absorber layer may be placed on the thermoplastic polymer. With the mask placed on the thermoplastic polymer, the thermoplastic polymer may be exposed to ultraviolet light.

The thermoplastic polymer patterned by exposure to ultraviolet rays may then be developed with a developer in step 933. The thermoplastic polymer may be a positive photoresist, and exposed portions of the positive photoresist may be dissolved by a photoresist developer. Unexposed portions of positive photoresist may be insoluble. Therefore, as shown in FIG. 9, portions of the coated thermoplastic polymer corresponding to the mask shape can be maintained after exposure to ultraviolet rays. If the mask is a circular mask, the thermoplastic polymer can be held in a cylindrical shape along a planar array pattern.

And in step 934, a hydrophobic coating 901 (e.g., Fluorocarbon nanofilm coating) may be applied on the thermoplastic polymer patterned structure. The cohesion of the thermoplastic polymer can be increased by the hydrophobic coating (901).

Subsequently, in step 935, a micro-lens shape may be manufactured through a thermal reflow process. Since the cohesion of the thermoplastic polymer is increased by the hydrophobic coating 901 applied in the above-described step 934, the thermoplastic polymer can be aggregated into a spherical shape.

However, the manufacturing of the image sensor according to one embodiment is not limited to the above-described FIGS. 7 to 9 and may change depending on the design. In addition, the order of each step of the manufacturing process described in FIGS. 7 to 9 is not limited to the above-mentioned, and some processes may be omitted or added.

Figure 10 shows an image taken with a scanning electron microscope of a structure in which lens elements are integrated on one side of a block layer according to an embodiment.

Figure 10 shows a lens element imaged by an electronic scanning electron microscope. As shown in FIG. 10, the lens element may be uniformly formed in a spherical shape along a grid pattern at the bottom of the block layer.

Figure 11 shows an image taken with an optical microscope of a structure in which lens elements are integrated on one side of a block layer according to an embodiment.

Figure 11 shows a lens element imaged by an optical microscope. As shown in FIG. 11, the focus of the lens element is formed uniformly and may appear as a white dot.

FIG. 12 is a diagram showing light transmittance according to the number of absorption layers included in a block layer according to an embodiment.

Figure 12 shows that as the number of absorption layers included in the block layer increases, the transmittance of light passing through the block layer decreases. For example, when a 4.5 μm absorbing layer is coated, about 40 to 50% of light can be transmitted through one layer. About 10% of light can be transmitted through two layers. In four layers, little light in the visible light region may be transmitted.

FIG. 13 shows images of the top and side surfaces of an image sensor according to an embodiment taken using a confocal laser scanning microscope.

FIG. 13 shows images taken for a structure 1310 without a lens array, a structure 1320 without a block layer, and a structure 1330 with a lens array and a block layer, respectively.

In the structure 1310 without a lens array photographed through a confocal laser scanning microscope, the light path is not focused. A structure without a block layer (1320) photographed through a confocal laser scanning microscope shows that light is not blocked.

The image sensor according to one embodiment has a structure 1330 having a lens array and a block layer, and can show the light path being focused while the light is blocked in the remaining portion except for the opening.

FIG. 14 is a diagram illustrating an intensity profile of an image sensor according to an embodiment.

FIG. 14 shows the results of comparing intensity profiles for each structure in FIG. 13. The image sensor according to one embodiment can block light by about 60% more effectively than a structure without a block layer. Additionally, in terms of focus, the image sensor according to one embodiment can display a uniform amount of light. A uniform amount of light may indicate that the lens is manufactured uniformly.

Figure 15 shows an image captured through an image sensor according to one embodiment.

The result of the image sensor shooting the original image at the top may appear like the image at the bottom. An image sensor according to an embodiment can obtain a plurality of clear segmented images while preventing crosstalk through a block layer.

Figure 16 shows the results of measuring the viewing angle of an image sensor according to an embodiment.

When an image sensor according to an embodiment captures a target object image, the viewing angle of the image sensor may be measured from the distance at which the object is observed to be completely filled in the image captured by the image sensor and the length of the target object image. The viewing angle of the image sensor shown in FIG. 16 may be approximately 70°.

Figures 17 and 18 are diagrams illustrating the effect of a block layer on a modulation transfer function (MTF) according to an embodiment.

FIG. 17 may show an MTF measurement image for a structure 1710 without a block layer and an MTF measurement image for a structure 1720 with a block layer. The MTF measurement image for the structure 1710 without a block layer may have low sharpness quality, but the structure 1710 with a block layer may exhibit high sharpness. As shown in FIG. 18, MTF can be measured for an image sensor with a block layer structure.

The image sensor according to one embodiment can be mounted on ultra-thin camera applications such as digital cameras for mobile devices. Additionally, image sensors can be applied to ultra-small optical imaging equipment such as endoscope cameras and drones.

In the image sensor according to one embodiment, an absorption layer to prevent optical crosstalk may be disposed on the opposite side of the sensing element with respect to the lens element, and an empty space between the lens element and the sensing element may be maintained by a spacer. Accordingly, the image sensor according to one embodiment can be implemented thinly.

The image sensor according to one embodiment reduces optical crosstalk through a block layer including an absorption layer and a transparent layer, and the viewing angle can be adjusted during manufacturing.

In the image sensor according to one embodiment, a lens element may be disposed on the lower surface of the block layer. Since the block layer is disposed on the upper surface of the lens element, optical crosstalk can be reduced. Additionally, a transparent substrate may be disposed on the upper surface of the block layer in the image sensor. Since a transparent substrate is placed on the top of the block layer, the received light is refracted and the viewing angle can be effectively expanded. The viewing angle of the image sensor can be adjusted through the thickness of the transparent layer and the number of absorption layers stacked. Additionally, the viewing angle of the image sensor can be determined by designing the area or diameter of the aperture formed in each absorption layer to have a different area or diameter from that of the other absorption layers.

The image sensor according to one embodiment can be integrated into a semiconductor and used as an ultra-thin camera. Additionally, the amount of light received by the image sensor can be adjusted by designing the width of the aperture formed in the laminated absorption layer and the f number (f number) of the lens element.

The method of manufacturing an image sensor according to an embodiment can manufacture a precise image sensor using a material capable of ultraviolet patterning. Additionally, the method of manufacturing an image sensor can produce an ultra-thin lens. By varying the diameter of the aperture formed in the absorption layer for each individual absorption layer, the viewing angle at which light enters can be adjusted. The focal length depending on the height of the spacer and the curvature of the lens element can also be changed depending on the design.

In an image sensor according to an embodiment, the viewing angle for individual sensing elements can be adjusted through the design of a block layer and lens element that provide light to individual sensing elements included in the sensor array. An image sensor may acquire a plurality of segmented images using a plurality of sensing elements. The image sensor can acquire segmented images with an adjusted degree of overlap according to the viewing angle adjustment according to the design of the block layer, etc. described above. Image sensors can improve the MTF for high-definition ultra-thin cameras or extract 3D depth information for 3D cameras.

The device described above may be implemented with hardware components, software components, and/or a combination of hardware components and software components. For example, devices and components described in embodiments may include, for example, a processor, a controller, an arithmetic logic unit (ALU), a digital signal processor, a microcomputer, a field programmable array (FPA), It may be implemented using one or more general-purpose or special-purpose computers, such as a programmable logic unit (PLU), microprocessor, or any other device capable of executing and responding to instructions. A processing device may perform an operating system (OS) and one or more software applications that run on the operating system. Additionally, a processing device may access, store, manipulate, process, and generate data in response to the execution of software. For ease of understanding, a single processing device may be described as being used; however, those skilled in the art will understand that a processing device includes multiple processing elements and/or multiple types of processing elements. It can be seen that it may include. For example, a processing device may include a plurality of processors or one processor and one controller. Additionally, other processing configurations, such as parallel processors, are possible.

Software may include a computer program, code, instructions, or a combination of one or more of these, which may configure a processing unit to operate as desired, or may be processed independently or collectively. You can command the device. Software and/or data may be used on any type of machine, component, physical device, virtual equipment, computer storage medium or device to be interpreted by or to provide instructions or data to a processing device. , or may be permanently or temporarily embodied in a transmitted signal wave. Software may be distributed over networked computer systems and stored or executed in a distributed manner. Software and data may be stored on one or more computer-readable recording media.

The method according to the embodiment may be implemented in the form of program instructions that can be executed through various computer means and recorded on a computer-readable medium. Computer-readable media may include program instructions, data files, data structures, etc., singly or in combination. Program instructions recorded on the medium may be specially designed and configured for the embodiment or may be known and available to those skilled in the art of computer software. Examples of computer-readable recording media include magnetic media such as hard disks, floppy disks, and magnetic tapes, optical media such as CD-ROMs and DVDs, and magnetic media such as floptical disks. -Includes optical media (magneto-optical media) and hardware devices specifically configured to store and execute program instructions, such as ROM, RAM, flash memory, etc. Examples of program instructions include machine language code, such as that produced by a compiler, as well as high-level language code that can be executed by a computer using an interpreter, etc. The hardware devices described above may be configured to operate as one or more software modules to perform the operations of the embodiments, and vice versa.

Although the embodiments have been described with limited drawings as described above, those skilled in the art can apply various technical modifications and variations based on the above. For example, the described techniques are performed in a different order than the described method, and/or components of the described system, structure, device, circuit, etc. are combined or combined in a different form than the described method, or other components are used. Alternatively, appropriate results may be achieved even if substituted or substituted by an equivalent.

Therefore, other implementations, other embodiments, and equivalents of the claims also fall within the scope of the claims described below.

100: image sensor
110: lens element
120: block layer
130: transparent substrate
140: Sensing element
150: spacer
190: Camera chip

Claims (20)

In the image sensor,
A block layer including an absorbing layer and a transparent layer, and allowing light received from the outside to pass through openings formed in the absorbing layer and the transparent layer; and
A lens element disposed below the block layer.
Including,
The lens element is,
Receives light passing through the block layer and transmits the light to a sensing element,
The absorbent layer and the transparent layer,
Alternately arranged in the block layer,
Image sensor. According to paragraph 1,
The sensing element is,
Spaced apart from the lens element and receiving light passing through the opening and the lens element,
Image sensor. According to paragraph 1,
The lens element is,
Refracting the light to form a focal point on the sensing element,
Image sensor. According to paragraph 1,
The block layer is,
Spaced apart from the sensing element by the focal length of the lens element,
Image sensor. According to paragraph 1,
The image sensor is,
Transparent substrate that allows light to pass through
An image sensor further comprising: According to paragraph 1,
The opening is
formed to be aligned with respect to the placement of the lens element in the block layer,
Image sensor. According to paragraph 1,
The image sensor is,
A spacer that maintains the gap between the block layer and the sensing element.
An image sensor further comprising: delete According to paragraph 1,
The absorption layer is,
Depending on the arrangement of the lens elements, an aperture is formed as a circular area centered on a point corresponding to the lens element in the absorption layer.
An image sensor including. According to paragraph 1,
The absorption layer is,
It includes an aperture of a first diameter formed around a point corresponding to the lens element,
The block layer is,
Further comprising another absorption layer formed with an aperture having a second diameter different from the first diameter,
Image sensor. According to paragraph 1,
The block layer is,
The diameter of the opening gradually changes from one side of the block layer to the other side,
Image sensor. According to paragraph 1,
The transparent layer is,
Transmitting light in a predetermined wavelength band,
Image sensor. According to paragraph 1,
The block layer is,
Having a height determined based on a predetermined viewing angle,
Image sensor. According to paragraph 1,
The block layer is,
A determined number of absorbing layers are laminated based on a predetermined viewing angle,
Image sensor. According to paragraph 1,
The block layer is,
Having an opening diameter determined based on a predetermined amount of light, and spaced apart from the sensing element by a focal distance determined based on the predetermined amount of light,
Image sensor. According to paragraph 1,
The transparent layer is,
Containing a transparent polymer that allows light to pass through,
Image sensor. According to paragraph 1,
The absorption layer is,
Containing a black matrix material that absorbs light,
Image sensor. According to paragraph 1,
A circular aperture formed in each of the plurality of absorption layers included in the block layer has a diameter determined based on a refractive index determined by the transparent substrate and the transparent layer and a predetermined viewing angle,
Image sensor. According to paragraph 1,
The lens element and sensing element are:
Arranged in a flat array pattern,
The absorption layer is,
Aperture formed by alignment with the planar array pattern
An image sensor including. In a method of manufacturing an image sensor,
providing a transparent substrate;
providing a block layer comprising an absorbent layer and a transparent layer;
Providing a lens element according to a pattern in which an opening is formed in the block layer
Including,
The lens element is,
is placed at the bottom of the block layer,
Receives light passing through the block layer,
Transmitting the light to the sensing element,
The absorbent layer and the transparent layer,
Arranged alternately in the block layers,
Manufacturing method of image sensor.

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