Image sensor

Abstract

To provide an image sensor with improved reliability.SOLUTION: The multilayer structure includes: a first substrate having an active pixel region in which a plurality of pixels are defined; and a pad region disposed on at least one side of the active pixel region, wherein the first substrate has a first surface and a second surface located opposite to the first surface, and wherein each of the plurality of pixels includes a photoelectric conversion region; a plurality of dielectric layers disposed on the first surface of the first substrate; and a nanoprism pattern arranged in at least one of the dielectric layers in the active pixel region, wherein the plurality of dielectric layers include: a meta-optical structure having a pad opening that exposes a bonding pad in the pad region; a passivation layer covering a portion of the plurality of dielectric layers provided on a side wall of the pad opening; and a second substrate disposed on the second surface of the first substrate, on which a logic element for driving the plurality of pixels is formed.SELECTED DRAWING: Figure 3

Description

[Technical Field]

[0001] The present invention relates to an image sensor, and more particularly to an image sensor with improved reliability. [Background technology]

[0002] An image sensor is a semiconductor-based sensor that receives light from an image projected by an optical structure according to position and color and generates an electrical signal. The optical structure of an image sensor mainly uses a microlens and a color filter for each pixel. However, with the demand for higher resolution cameras, the pixel size is gradually becoming smaller and the size of the optical structure is gradually becoming smaller.

[0003] However, miniaturization of such optical structures leads to a problem of reduced optical efficiency of the image sensor. As an alternative to conventional optical structures, there has been active research into the introduction of structures based on a new optical technology called "meta-optics." Summary of the Invention [Problem to be solved by the invention]

[0004] The present invention has been made in view of the above-mentioned problems with conventional image sensors, and an object of the present invention is to provide an image sensor with improved reliability. [Means for solving the problem]

[0005] The image sensor according to the present invention, which has been made to achieve the above object, comprises a laminated structure including an active pixel area in which a plurality of pixels are defined and a pad area disposed on at least one side of the active pixel area, wherein the laminated structure comprises: a first substrate having a first surface and a second surface opposite to the first surface and including a photoelectric conversion area in each of the plurality of pixels; a plurality of dielectric layers disposed on the first surface of the first substrate; and a nanoprism pattern arranged in at least one of the plurality of dielectric layers in the active pixel area, wherein the plurality of dielectric layers include a meta-optical structure having a pad opening exposing a bonding pad in the pad area; a passivation layer covering portions of the plurality of dielectric layers provided on sidewalls of the pad opening; and a second substrate disposed on the second surface of the first substrate and on which logic elements for driving the plurality of pixels are formed.

[0006] Also, an image sensor according to the present invention, which has been made to achieve the above object, comprises a laminated structure including an active pixel area in which a plurality of pixels are defined and a pad area disposed on at least one side of the active pixel area, the laminated structure comprising: a first substrate having a first surface and a second surface opposite to the first surface, the first substrate including a photoelectric conversion area in each of the plurality of pixels; a plurality of dielectric layers disposed on the first surface of the first substrate; and a nanoprism pattern arranged in at least one of the plurality of dielectric layers in the active pixel area, The plurality of dielectric layers include a meta-optical structure having a pad opening exposing a bonding pad in the pad region, and a second substrate disposed on a second surface of the first substrate and on which logic elements for driving the plurality of pixels are formed, the plurality of dielectric layers including a first mold layer having a first nanoprism pattern and a second mold layer having a second nanoprism pattern on the first mold layer, the first mold layer having a first edge portion spaced from a sidewall of the pad opening, and the second mold layer covering the first edge portion of the first mold layer.

[0007] and a second substrate, the second substrate being disposed on a second surface of the first substrate, on which logic elements for driving the pixels are formed. The second substrate includes a first substrate having a first surface and a second surface opposite the first surface, the first substrate including a photoelectric conversion region for each of the pixels, a plurality of dielectric layers disposed on the first surface of the first substrate, and a nanoprism pattern arranged in at least one of the dielectric layers in the active pixel region. The first substrate includes a meta-optical structure having a pad opening exposing a bonding pad, a transparent planarization layer disposed between the first surface of the first substrate and the meta-optical structure, the transparent planarization layer having an edge portion spaced from a sidewall of the pad opening, the edge portion of the transparent planarization layer being covered by the plurality of dielectric layers. The second substrate is disposed on a second surface of the first substrate, on which logic elements for driving the pixels are formed. [Effects of the Invention]

[0008] According to the image sensor of the present invention, in an image sensor having a meta-optical structure, defects (such as undercut, peeling, or cracks) occurring in a composite film (the multilayer film of the meta-optical structure and / or the insulating layer below the meta-optical structure) exposed on the sidewall of an opening for a bonding pad can be prevented, thereby improving the reliability of the image sensor. [Brief explanation of the drawings]

[0009] [Figure 1] 1 is an exploded perspective view showing a schematic configuration of an image sensor according to an embodiment of the present invention; [Figure 2] FIG. 2 is a plan view of region “A” of the image sensor of FIG. [Figure 3] FIG. 3 is a cross-sectional view of the region of FIG. 2 taken along line II'. [Figure 4]1 is a cross-sectional view showing a schematic configuration of an image sensor according to an embodiment of the present invention. [Figure 5a] 4A to 4C are cross-sectional views illustrating steps in a method for manufacturing the image sensor of FIG. 3. [Figure 5b] 4A to 4C are cross-sectional views illustrating steps in a method for manufacturing the image sensor of FIG. 3. [Figure 5c] 4A to 4C are cross-sectional views illustrating steps in a method for manufacturing the image sensor of FIG. 3. [Figure 5d] 4A to 4C are cross-sectional views illustrating steps in a method for manufacturing the image sensor of FIG. 3. [Figure 5e] 4A to 4C are cross-sectional views illustrating steps in a method for manufacturing the image sensor of FIG. 3. [Figure 5f] 4A to 4C are cross-sectional views illustrating steps in a method for manufacturing the image sensor of FIG. 3. [Figure 5g] 4A to 4C are cross-sectional views illustrating steps in a method for manufacturing the image sensor of FIG. 3. [Figure 6] FIG. 10 is a cross-sectional view showing a schematic configuration of an image sensor according to another embodiment of the present invention. [Figure 7] FIG. 10 is a cross-sectional view showing a schematic configuration of an image sensor according to another embodiment of the present invention. [Figure 8a] 7A to 7C are cross-sectional views illustrating steps in a method for manufacturing the image sensor of FIG. 6. [Figure 8b] 7A to 7C are cross-sectional views illustrating steps in a method for manufacturing the image sensor of FIG. 6. [Figure 8c] 7A to 7C are cross-sectional views illustrating steps in a method for manufacturing the image sensor of FIG. 6. [Figure 8d] 7A to 7C are cross-sectional views illustrating steps in a method for manufacturing the image sensor of FIG. 6. [Figure 9] FIG. 10 is a cross-sectional view showing a schematic configuration of an image sensor according to another embodiment of the present invention. [Figure 10] FIG. 10 is a cross-sectional view showing a schematic configuration of an image sensor according to another embodiment of the present invention. [Figure 11] FIG. 10 is a cross-sectional view showing a schematic configuration of an image sensor according to another embodiment of the present invention. [Figure 12a]10A to 10C are cross-sectional views illustrating steps in a method for manufacturing the image sensor of FIG. 9. [Figure 12b] 10A to 10C are cross-sectional views illustrating steps in a method for manufacturing the image sensor of FIG. 9. [Figure 12c] 10A to 10C are cross-sectional views illustrating steps in a method for manufacturing the image sensor of FIG. 9. [Figure 12d] 10A to 10C are cross-sectional views illustrating steps in a method for manufacturing the image sensor of FIG. 9. [Figure 12e] 10A to 10C are cross-sectional views illustrating steps in a method for manufacturing the image sensor of FIG. 9. [Figure 13] FIG. 10 is a cross-sectional view showing a schematic configuration of an image sensor according to another embodiment of the present invention. [Figure 14] FIG. 10 is a cross-sectional view showing a schematic configuration of an image sensor according to another embodiment of the present invention. [Figure 15a] 14A to 14C are cross-sectional views illustrating steps in a method for manufacturing the image sensor of FIG. 13. [Figure 15b] 14A to 14C are cross-sectional views illustrating steps in a method for manufacturing the image sensor of FIG. 13. [Figure 15c] 14A to 14C are cross-sectional views illustrating steps in a method for manufacturing the image sensor of FIG. 13. [Figure 16] FIG. 10 is a cross-sectional view showing a schematic configuration of an image sensor according to another embodiment of the present invention. [Figure 17] FIG. 10 is a cross-sectional view showing a schematic configuration of an image sensor according to another embodiment of the present invention. DETAILED DESCRIPTION OF THE INVENTION

[0010] Next, specific examples of embodiments for carrying out the image sensor according to the present invention will be described with reference to the drawings.

[0011] FIG. 1 is an exploded perspective view showing the schematic configuration of an image sensor according to one embodiment of the present invention, FIG. 2 is a plan view of region "A" of the image sensor of FIG. 1, and FIG. 3 is a cross-sectional view of the region of FIG. 2 taken along line II'.

[0012] 1 to 3, an image sensor 10 according to the present embodiment includes a stacked structure ST in which a first substrate structure 100 and a second substrate structure 200 are stacked and electrically connected to each other. The laminated structure ST employed in this embodiment includes an active pixel region APR in which a plurality of pixels PX are arranged, a pad region PDR arranged on at least one side of the active pixel region APR, and an optical black region OB and a connection region CR between the active pixel region APR and the pad region PDR.

[0013] As shown in FIG. 1, the active pixel region APR is disposed in the center of the laminated structure ST. A plurality of pixels PX are arranged in the active pixel region APR. A plurality of pixels PX are arranged in a matrix shape in the active pixel region APR on the first substrate 110, forming columns and rows along a first direction D1 and a second direction D2 perpendicular to the first direction D1. Each of the plurality of pixels PX includes at least one photoelectric conversion region PD formed in the first substrate 110. The plurality of pixels PX are regions that receive light from outside the laminated structure ST and convert it into an electrical signal. For example, the plurality of pixels PX include a photoelectric conversion region PD for receiving external light and a transistor that constitutes a pixel circuit for converting photocharges accumulated in the photoelectric conversion region PD into an electrical signal.

[0014] The pad region PDR is disposed on at least one side of the active pixel region APR, for example, on three side surfaces of the active pixel region APR as shown in FIG. A plurality of bonding pads 390 are arranged in the pad region PDR and are configured to transmit and receive electrical signals to and from an external device or the like.

[0015] Between the active pixel region APR and the pad region PDR, an optical black region OB and a connection region CR are sequentially arranged around the active pixel region APR. The optical black area OB is an area where light is blocked and includes optical black pixels PX' that generate dark signals to function as reference pixels for the active pixel area APR, and dummy pixels DX are further arranged around the optical black pixels PX' (see Figure 2). The connection region CR is located on one side of the optical black region OB, but this is merely an example. In the connection region CR, the first wiring layer 125 and the second wiring layer 225 are connected by the first connection structure 360, so that electrical signals in the photoelectric conversion region PD are transmitted and received to and from the circuit of the second substrate 210. As described above, referring to FIG. 3, the image sensor 10 according to this embodiment includes a stack structure ST having a first substrate structure 100 and a second substrate structure 200. As shown in FIG.

[0016] The first substrate structure 100 includes a first substrate 110 having a first surface 110a and a second surface 110b positioned opposite each other, a front optical structure 300 on the first surface 110a of the first substrate 110, and a first wiring structure 120 on the second surface 110b of the first substrate 110. The second substrate structure 200 includes a second substrate 210 having an upper surface on which a logic element 215 is disposed, and a second wiring structure 220 on the second substrate 210 in contact with the first wiring structure 120 . The first substrate structure 100 is also called a "sensor chip," and the second substrate structure 200 is also called a "logic chip." Although the image sensor according to the present embodiment is illustrated as a stacked structure having two substrates, it is not limited thereto, and in one embodiment, it may include a stacked structure having three substrates. For example, the transistors for the pixel circuits implemented on the first substrate 110 may be implemented as a separate middle plate.

[0017] The image sensor 10 according to this embodiment includes a meta-optical structure 400 instead of an optical lens. Here, the meta-optical structure 400 is referred to as an optical structure based on meta-optics, and is also referred to as a meta-surface or a metalens. In this embodiment, the meta-optical structure 400 is arranged on the first surface 110a of the first substrate 110, which is the incident surface side, and is configured to split the incident light according to wavelength (e.g., color) and concentrate the split light on the photoelectric conversion regions PD of different pixels PX.

[0018] Referring to FIG. 3, the meta-optical structure 400 is a multilayer structure including multiple dielectric layers (410, 421, 422) and includes nanoprism patterns (NP1, NP2) that are nanoscale structures (e.g., post structures) arranged within at least one of the multiple dielectric layers (421, 422). In this embodiment, the nanoprism patterns (NP1, NP2) are arranged in overlapping areas in the active pixel regions APR. The plurality of dielectric layers (410, 421, 422) extend not only over the active pixel region APR but also through the optical black region OB and the connection region CR to the pad region PDR.

[0019] In this embodiment, a pad opening OP for exposing the bonding pad 390 is formed in the portion of the meta-optical structure 400 that extends to the pad region PDR. The portion extended to the pad region PDR includes only the plurality of dielectric layers (410, 421, 422) without the nanoprism patterns (NP1, NP2). Since the interfaces of the multiple dielectric layers (410, 421, 422) and / or the interface between the meta-optical structure 400 and the transparent planarization layer 350 are exposed at the inner sidewalls of the pad opening OP, peeling or cracking may occur due to mechanical shock or moisture absorption in subsequent processes, or the transparent planarization layer 350 may be over-etched during the formation process of the pad opening OP, resulting in undercut, which may cause reliability issues.

[0020] To prevent such problems, the image sensor 10 according to this embodiment includes a passivation layer PL disposed on the inner sidewall of the pad opening OP. A passivation layer PL is formed over the exposed interface of the meta-optical structure 400 and the side surfaces of the transparent planarization layer 350 . The detailed structure and arrangement of the meta-optical structure 400 and the passivation layer PL employed in this embodiment will be described later.

[0021] Referring to FIG. 3, the first substrate 110 of the first substrate structure 100 is a semiconductor substrate. For example, the first substrate 110 is a bulk silicon or SOI (silicon-on-insulator) substrate. The first substrate 110 includes a pixel separating pattern 150 that defines a plurality of pixels PX.

[0022] The pixel separating pattern 150 is formed to surround the photoelectric conversion region PD. At least one photoelectric conversion region PD is formed in the first substrate 110 in each of the plurality of pixels PX. The photoelectric conversion region PD generates electric charges in proportion to the amount of light incident from the outside. For example, the photoelectric conversion region PD can be a photo diode, a photo transistor, a photo gate, a pinned photo diode, or an organic photo diode. The photoelectric conversion region PD is disposed within the active pixel region APR.

[0023] As described above, in the optical black area adjacent to the active pixel area APR, the reference photoelectric conversion area PD' constitutes a reference pixel RX that generates a dark signal for reference to the active pixel area APR. The dummy photoelectric conversion regions NPD are provided as dummy pixel regions DX that are not provided as photoelectric conversion elements. The reference photoelectric conversion region PD′ and the dummy photoelectric conversion region NPD are also separated by the pixel separating pattern 150.

[0024] The pixel separating pattern 150 has a grid shape that separates a plurality of pixels PX from a plan view. For example, the pixel separating pattern 150 penetrates at least a portion of the first substrate 110 . In this embodiment, the pixel separating pattern 150 includes a deep trench that extends from the second surface 110b to the first surface 110a. The pixel isolation pattern 150 includes an insulating liner (not shown) on the sidewalls of the deep trench and a filler disposed within the insulating liner. For example, the insulating liner may include silicon oxide, silicon nitride, and / or silicon oxynitride, and the fill may include a semiconductor or conductive material. For example, the filler comprises impurity-doped polycrystalline silicon.

[0025] On the second surface 110b of the first substrate 110, an isolation pattern 112 is formed to define an active region. In the active region, a floating diffusion region FD and elements for pixel circuits are formed. The pixel circuit elements include various transistor-like circuit elements such as a transfer gate TG. The pixel isolation pattern 150 is connected to the device isolation pattern 112, which is a shallow trench structure. In this embodiment, the element isolation pattern 112 is disposed on the pixel isolation pattern 150 . For example, the isolation pattern 112 includes silicon oxide.

[0026] The first wiring structure 120 includes a first inter-wiring insulating layer 121 and a plurality of first wirings 125 on the first inter-wiring insulating layer 121 . The number of layers of wiring constituting the first wiring structure 120 and their arrangement shown in the drawings are merely exemplary. For example, the first inter-wiring insulating layer 121 may include at least one of silicon oxide, silicon nitride, silicon oxynitride, and a low-k material having a lower dielectric constant than silicon oxide. For example, the first wiring 125 may include at least one of tungsten (W), copper (Cu), aluminum (Al), gold (Au), silver (Ag), and alloys thereof.

[0027] The second substrate 210, like the first substrate 110, is a bulk silicon or SOI (silicon-on-insulator) substrate. A logic element 215 is disposed on the second substrate 210 . The logic element 215 provides a constant signal to each pixel PX in the active pixel region APR, or constitutes a circuit that controls an output signal from each pixel PX. For example, the logic element 215 may include various transistors that form a control register block, a timing generator, a ramp signal generator, a row driver, a readout circuit, and / or an input / output (I / O) buffer circuit.

[0028] The second wiring structure 220 is disposed between the first wiring structure 120 of the first substrate structure 100 and the second substrate 210 . The second wiring structure 220 includes a second inter-wiring insulating layer 221 and a plurality of second wirings 225 on the second inter-wiring insulating layer 221 . The number of layers of wiring that make up the second wiring structure 220 and their arrangement are merely exemplary. The plurality of first wirings 225 include vias that electrically connect the logic elements 215 together. For example, the second inter-wiring insulating layer 221 may include at least one of silicon oxide, silicon nitride, silicon oxynitride, and a low-k material having a dielectric constant lower than that of silicon oxide. The second wiring 225 may include, for example, at least one of tungsten (W), copper (Cu), aluminum (Al), gold (Au), silver (Ag), and alloys thereof.

[0029] In this embodiment, the first wiring structure 120 is bonded to the second wiring structure 220 . In one embodiment, each of the first and second wiring structures (120, 220) includes a bonding insulating layer (not shown) disposed on the surfaces to be bonded. In addition, the first and second substrate structures (100, 200) are coupled together by first and second connection structures (360, 370) that penetrate the first substrate structure (100) and are connected to the second substrate structure (200). The first and second connection structures (360, 370) electrically connect the first wiring layer 125 and the second wiring layer 225 in the connection region CR and the pad region PDR, respectively.

[0030] Referring to FIG. 3, the first substrate structure 100 includes a front optical structure 300 disposed on the first surface 110 a of the first substrate 110 . The front optical structure 300 includes a surface insulating layer 310, a grid pattern 320, a protective film 330, a color filter 340, and a transparent planarization layer 350, along with the meta-optical structure 400 described above.

[0031] The surface insulating layer 310 is disposed on the first surface 110 a of the first substrate 110 . The surface insulating layer 310 extends not only to the active pixel region APR but also to the peripheral region OB / CR and the pad region PDR. The surface insulating layer 310 includes an insulating material. For example, the surface insulating layer 310 may include, but is not limited to, at least one of silicon oxide, silicon nitride, silicon oxynitride, aluminum oxide, hafnium oxide, and combinations thereof. The surface insulating layer 310 may also be a multi-layer film. For example, the surface insulating layer 310 may include, but is not limited to, an aluminum oxide film, a hafnium oxide film, a silicon oxide film, a silicon nitride film, and a hafnium oxide film sequentially stacked on the first surface 110a of the first substrate 110. The surface insulating layer 310 functions as an anti-reflection film, and can improve the light receiving efficiency of the photoelectric conversion region PD by preventing reflection of light incident on the first substrate 110.

[0032] In the active pixel area, color filters 340 and grid patterns 320 between the color filters 340 are disposed on the surface insulating layer 310 . The color filter 340 is disposed on the surface insulating layer 310 . The color filters 340 are arranged to correspond to the respective pixels PX in the active pixel region APR. The color filter 340 has various color filters for each pixel. For example, the color filter 340 includes a red color filter, a green color filter, and a blue color filter. In one embodiment, the color filters 340 are arranged in a Bayer pattern. However, this is merely an example, and the color filter 340 may include a yellow filter, a magenta filter, and a cyan filter, and may further include a white filter.

[0033] The grid pattern 320 has a lattice shape when viewed from a plan view. In one embodiment, the grid pattern 320 is positioned to overlap the pixel separation pattern 150 in the vertical direction (eg, D3). In one embodiment, the grid pattern 320 includes a conductive pattern and a low refractive index pattern. The conductive pattern prevents charges generated by ESD or the like from accumulating on the surface of the first substrate 110, thereby effectively preventing ESD failures. The low refractive index pattern can improve the light collection efficiency by refracting or reflecting obliquely incident light, thereby improving the quality of the image sensor. For example, the conductive pattern may include at least one of titanium (Ti), titanium nitride (TiN), tantalum (Ta), tantalum nitride (TaN), tungsten (W), aluminum (Al), and copper (Cu). The low refractive index pattern includes a low refractive index material having a refractive index lower than that of silicon (Si). For example, the low refractive index pattern may include at least one of silicon oxide, aluminum oxide, tantalum oxide, and combinations thereof.

[0034] Referring to FIG. 3, in the peripheral region OB / CR, a first conductive layer 361 and a light-shielding filter layer 340L are sequentially disposed on the surface insulating layer 310. In one embodiment, the light-shielding filter layer 340L provides an optical black area OB and, together with the first conductive layer 361, serves as a light-shielding structure that blocks light. In one embodiment, the light-blocking filter layer 340L is formed together with a portion of the color filter 340. It has substantially the same thickness as the color filter 340, but is not limited to this. The light-shielding filter layer 340L includes a blue color filter or a black filter.

[0035] Referring to FIG. 3, a bias contact plug 380 and a first conductive layer 361 are disposed in the optical black area OB. The first conductive layer 361 covers the surface insulating layer 310 on the first surface 110 a of the first substrate 110 . The first conductive layer 361 conformally covers the inner wall of the first trench TR1 and is connected to the pixel separating pattern 150. The bias contact plug 380 fills the first trench TR1. The bias contact plug 380 includes a metal material (eg, aluminum). The bias contact plug 380 is connected to the pixel separating pattern 150 through the first conductive layer 361 . A bias is applied to the pixel separating pattern 150 through the bias contact plug 380 .

[0036] The first connection structure 360 ​​is disposed in the connection region CR. The first connection structure 360 ​​includes a first connection layer 362 , a first separation pattern 363 , and a first capping pattern 365 . The first connection structure 360 ​​penetrates the first substrate structure 100 and the second substrate structure 200 (particularly, a part of the second wiring structure 220) to electrically connect the first wiring layer 125 and the second wiring layer 225 to each other. The first connection layer 362 includes a metal material (eg, tungsten). The first connection layer 362 is formed together with the first conductive layer 361 .

[0037] In the pad region PDR, a second connection structure 370 and a bonding pad 390 are arranged. The second connection structure 560 includes a second connection layer 372 , a second isolation pattern 373 , and a second capping pattern 375 . The second connection structure 370 penetrates the first substrate structure 100 and the second substrate structure 200 (particularly, a part of the second wiring structure 220) to connect the first wiring layer 125 and the second wiring layer 225 to each other. The second conductive layer 371 is disposed on the surface insulating layer 310 on the first surface 110 a of the first substrate 110 , and the second connecting layer 372 extends from the second conductive layer 371 . The second conductive layer 371 conformally covers the inner wall of the second trench TR2. The second conductive layer 371 and the second connection layer 372 include the same metal material (for example, tungsten).

[0038] In this embodiment, the bonding pad 390 is formed by filling the second trench TR2. The bonding pad 390 includes a metal material (for example, aluminum). The bonding pad 390 connects the second conductive layer 371 and the second connection structure 370 (particularly, the second connection layer 372) to the second wiring layer 225, and is connected to the logic element 215 of the second substrate 210 through the second wiring layer. Bonding pads 390 serve as electrical connection paths between image sensor 10 and external devices. For example, electrical signals generated from the photoelectric conversion regions PD in the plurality of pixels PX of the active pixel region APR are processed by the pixel circuit of the first substrate and the logic circuit of the second substrate 210 and transmitted to an external device through the bonding pads 390.

[0039] Referring to FIG. 3, the transparent planarization layer 350 is formed not only in the active pixel region APR but also in the peripheral regions thereof, that is, the optical black region OB, the connection region CR, and the pad region PDR. The transparent planarization layer 350 covers the color filter 340, the light-shielding filter layer 340L, and the first and second connecting structures (360, 370) on the first surface 110a of the first substrate 110, and provides a flat upper surface. The transparent planarization layer 350 comprises a light-transmitting material. In one embodiment, the transparent planarization layer 350 may include an organic material such as an acrylic resin, a styrene resin, a polyimide resin, or a siloxane resin.

[0040] In this embodiment, the meta-optical structure 400 is provided on a transparent planarization layer 350 . As described above, the meta-optical structure 400 includes a plurality of dielectric layers (410, 421, 422) and nanoprism patterns (NP1, NP2) arranged within at least one of the plurality of dielectric layers (421, 422). The meta-optical structure 400 employed in this embodiment includes a base dielectric layer 410 and first and second mold layers (421, 422) having first and second nanoprism patterns (NP1, NP2), respectively. The first and second nanoprism patterns (NP1, NP2) are appropriately designed in terms of refractive index, shape, and height depending on the wavelength. The nanoprism pattern used in this embodiment is exemplified as a form in which two mold layers (421, 422) are introduced to obtain the height required to ensure the desired phase difference, and the first and second nanoprism patterns (NP1, NP2) are arranged in an overlapping manner, but this is not limited to this, and nanoprism patterns of various forms (shapes, heights, etc.) can be realized by introducing one mold layer or three or more mold layers.

[0041] For example, the first and second mold layers (421, 422) may comprise a transparent inorganic material such as silicon oxide, silicon oxynitride, silicon nitride, silicon carbonate, or silicon carbonitride. The base dielectric layer 410 comprises the same or similar material as the first and second mold layers (421, 422). The first and second nanoprism patterns (NP1, NP2) are selected from materials having an appropriate refractive index depending on the wavelength of the incident light. For example, the first and second nanoprism patterns (NP1, NP2) may include transparent inorganic materials such as titanium oxide, silicon nitride, niobium oxide, tantalum oxide, aluminum oxide, and hafnium oxide.

[0042] In one embodiment, as shown in FIG. 3, first and second etch stop films (431, 432) are disposed between the base dielectric layer 410 and the first mold layer 421, and between the first and second mold layers (421, 422). The first and second etch stop films (431, 432) are used to form holes for the first and second nanoprism patterns (NP1, NP2) in the first and second mold layers (421, 422), respectively (see, for example, FIG. 12a). The first and second etch stop films (431, 432) include, for example, aluminum oxide.

[0043] The meta-optical structure 400 employed in this embodiment includes an anti-reflection layer 450 on the second mold layer 422 . The anti-reflection layer 450 can prevent reflection of light incident on the meta-optical structure 400, thereby increasing the light receiving efficiency. The anti-reflection layer 450 includes a material having a different refractive index than the material of the second mold layer 422 . For example, the antireflective layer 450 may include silicon nitride, aluminum oxide, or hafnium oxide. In this embodiment, the anti-reflection layer 450 includes a large number of holes h (see FIG. 2). By introducing holes h into the antireflection layer 450, it is possible to not only prevent optical interference but also increase the light absorption and improve the antireflection function. In one embodiment, a third etch stop film 433 is disposed between the anti-reflection layer 450 and the second mold layer 422 for the formation of the holes h. As described above, the first and second nanoprism patterns (NP1, NP2) are disposed only in the active pixel area APR, while the base dielectric layer 410 and the first and second mold layers (421, 422) extend to the peripheral area OB / CR and pad area PDR.

[0044] In this embodiment, the pad opening OP exposing the bonding pad 390 is formed through the meta-optical structure 400 portion extended to the pad region PDR, the transparent planarization layer 350 portion, the protective film 330 portion, and the like. Therefore, many interfaces of multiple layers are exposed on the inner sidewall of the pad opening OP. The introduction of the meta-optical structure 400 adds interfaces of multiple dielectric layers (410, 421, 422), and if the transparent planarization layer 350 contains an organic material, undercutting may occur during the dry etching process for forming the pad opening OP, potentially resulting in reliability issues such as peeling of the meta-optical structure 400. In this embodiment, to prevent this, a passivation layer PL is formed on the inner sidewall of the pad opening OP. The passivation layer PL covers the exposed interface of the meta-optical structure 400 and the exposed side surface of the transparent planarization layer 330, and can effectively prevent reliability problems caused by the formation of the pad opening OP.

[0045] In this embodiment, the passivation layer PL is formed together with the anti-reflection layer 450 as part of the anti-reflection layer 450 . The passivation layer PL comprises the same material as the anti-reflection layer 450 . For example, the passivation layer PL may comprise silicon nitride, aluminum oxide, or hafnium oxide. In one embodiment, the passivation layer PL, unlike the anti-reflection layer 450, is formed on a substantially vertical side and therefore may have a thickness (t2a, t2b) different from the thickness t1 of the anti-reflection layer on the top surface of the meta-optical structure 400. For example, the thickness (t2a, t2b) of the passivation layer PL is smaller than the thickness t1 of the antireflection layer 450.

[0046] In this embodiment, the anisotropic etching process that forms the holes h in the anti-reflection layer 450 is also applied to the passivation layer PL. In this step, in the process of forming the hole h in the antireflection layer 450, the antireflection layer portion is removed at the bottom of the pad opening OP while the passivation layer PL remains on the sidewall of the pad opening OP. In this process, the upper end portion of the passivation layer PL is partially etched, and the passivation layer PL has a rounded portion R. For example, the thickness t2b of the upper end portion of the passivation layer PL is smaller than the thickness t2a of the lower end portion of the passivation layer PL. The anti-reflection layer 450 also has a portion 450E that extends to the peripheral region (eg, the optical black region OB and the connection region CR).

[0047] FIG. 4 is a cross-sectional view showing a schematic configuration of an image sensor according to one embodiment of the present invention. Referring to FIG. 4, the image sensor 10A according to this embodiment can be understood to have a similar structure to the image sensor 10 shown in FIGS. 1 to 3 (particularly FIG. 3), except that the bonding pad 390 is disposed on the second substrate structure 200, the pad opening OP penetrates the first substrate structure 100, and the first substrate structure 100 and the second substrate structure 200 are connected by hybrid bonding between metal and dielectric instead of a connection structure (360, 370 in FIG. 3) that is a through structure. Furthermore, unless otherwise specifically described, the components of this embodiment can be understood by reference to the description of the same or similar components of the image sensor 10 shown in FIGS.

[0048] In this embodiment, the first substrate structure 100 and the second substrate structure 200 are connected by metal-dielectric hybrid bonding. First and second bonding structures 190 and 290 are disposed on the opposing surfaces of the first wiring structure 120 and the second wiring structure 220, respectively. The first bonding structure 190 includes a first bonding insulating layer 191 disposed on the first wiring structure 120 and a first bonding pad 195 electrically connected to the first wiring layer 125 on the bonding surface of the first bonding insulating layer 191.

[0049] The first bonding pad 195 has a surface that is substantially flat with the bonding surface of the first bonding insulating layer 191 . Similarly, the second bonding structure 290 includes a second bonding insulating layer 291 arranged on the second wiring structure 220 and a second bonding pad 295 electrically connected to the second wiring layer 225 on the bonding surface of the second bonding insulating layer 192. The second bonding pad 295 has a surface that is substantially flat with the bonding surface of the second bonding insulating layer 292 . The first and second bonding structures (190, 290) are hybrid-bonded together through a high-temperature annealing process. The hybrid bonding includes inter-metallic bonding of the first and second bonding electrodes (195, 295) and inter-dielectric bonding of the first and second bonding insulating layers (191, 291).

[0050] By this hybrid bonding, the first substrate structure 100 and the second substrate structure 200 are firmly bonded to each other, and the first and second wiring layers 125 and 225 are electrically connected through metal-to-metal bonding. Therefore, the first and second bonding pads (195, 295) replace some or all of the first and second connection structures (360, 370) used to connect the first and second wiring layers (125, 225) in the above-described embodiment (see FIG. 3).

[0051] In this embodiment, a bonding pad 390 for connecting to an external element is disposed on the second substrate structure 200, and a pad opening OP is formed through the first substrate structure. Referring to FIG. 4, the bonding pad 390 is disposed on the upper surface of the second wiring structure 220 and is connected to the second wiring layer 225 . The pad opening OP penetrates through the first and second bonding structures (190, 290) as well as the first substrate structure 100 to expose the bonding pad 390.

[0052] The passivation layer PL extends to cover the sidewalls exposed by the pad opening OP. In this embodiment, the passivation layer PL extends to cover the exposed inner sidewalls of the first substrate structure 100 and the exposed inner sidewalls of the first and second bonding structures (190, 290). As in the previous embodiment, the passivation layer PL comprises the same material as the anti-reflection layer 450 . For example, the passivation layer PL may comprise silicon nitride, aluminum oxide, or hafnium oxide.

[0053] In one embodiment, the passivation layer PL has a thickness (t2a, t2b) that is different from the thickness t1 of the anti-reflection layer 450. For example, the thickness (t2a, t2b) of the passivation layer PL is smaller than the thickness t1 of the antireflection layer 450. In one embodiment, for example, the thickness t2b of the upper end portion of the passivation layer PL is smaller than the thickness t2a of the lower end portion of the passivation layer PL. The upper end portion of the passivation layer PL has a rounded portion R.

[0054] Figures 5a to 5d are cross-sectional views of processes to explain the manufacturing method of the image sensor of Figure 3, and show the process of forming the meta-optical structure 400 and the process of forming the pad opening OP and the passivation layer PL in the manufacturing method of the image sensor of Figure 1. In this embodiment, first, a transparent planarization layer 350 is formed on the light incident surface side of the image sensor 10, and then a meta-optical structure 400 is formed as shown in FIGS. 5a to 5d.

[0055] Referring to FIG. 5a, a base dielectric layer 410, a first etch stop layer 431, and a first mold layer 421 are sequentially formed on a transparent planarization layer 350. For example, the base dielectric layer 410 and the first mold layer 421 may include a transparent inorganic material such as silicon oxide, silicon oxynitride, silicon nitride, silicon carbonate, or silicon carbonitride, and are formed by a deposition process. For example, the first etch stop film 431 includes aluminum oxide.

[0056] Next, referring to FIG. 5b, the first mold layer 421 is etched using the first etch stop film 431 to form a hole pattern H1 for the first nanoprism pattern NP1. Next, referring to FIG. 5c, a pattern material layer 440L is formed on the first mold layer 421 to fill the hole pattern H1, and a planarization process is performed to expose the top surface of the first mold layer 421, thereby forming a first nanoprism pattern NP1 defined by the hole pattern H1. The pattern material layer 440L constituting the first nanoprism pattern NP1 is selected from a material having an appropriate refractive index depending on the wavelength of the incident light. For example, the pattern material layer 440L may include a transparent inorganic material such as titanium oxide, silicon nitride, niobium oxide, tantalum oxide, aluminum oxide, and hafnium oxide.

[0057] Next, referring to FIG. 5d, second mold layer 422 having second nanoprism pattern NP2 is formed on first mold layer 421 having first nanoprism pattern NP1. The second mold layer 422 having the second nanoprism pattern NP2 is formed by a process similar to that of FIGS. 5b and 5c. Specifically, a second etch stop layer 432 and a second mold layer 422 are sequentially formed on a first mold layer 421 . The second etch stop layer 432 and the second mold layer 422 are made of the same material as the first etch stop layer 431 and the first mold layer 421, respectively. Next, similar to the process of Figure 5b, a hole pattern is formed in the second mold layer 422, and similar to the process of Figure 5c, the hole pattern is filled with a pattern material layer, and then a CMP process is performed to form the desired second nanoprism pattern NP2 in the second mold layer 422.

[0058] As shown in FIG. 5d, the stack of the meta-optical structure 400, excluding the first and second nanoprism patterns, is extended to the peripheral region OB / CR and the pad region PDR. Specifically, the base dielectric layer 410 and the first and second mold layers (421, 422) are extended to the peripheral region OB / CR and the pad region PDR.

[0059] Next, referring to FIG. 5e, a pad opening OP connected to the bonding pad 390 is formed in the pad region PDR. In this embodiment, the pad opening OP is formed through the stack (410, 421, 422) of the meta-optical structure 400 and the transparent planarization layer 340. In this step, the protective film 330 covering the bonding pad 390 is not removed but remains. The remaining protective film 330 protects the bonding pad 390 in the subsequent passivation layer forming process.

[0060] Next, referring to FIG. 5f, an anti-reflective material layer 450L is formed on the top surface of the meta-optical structure 400 and on the surface exposed by the pad opening OP. The anti-reflective material layer 450L is deposited relatively conformally on the top surface of the meta-optical structure 400 as well as on the surface exposed by the pad opening OP. However, in one embodiment, the thickness t2 of the anti-reflective material layer located on the inner sidewall of the pad opening OP is less than the thickness t1 of the anti-reflective material layer located on the top surface of the meta-optical structure 400. For example, the antireflective material layer 450L can include silicon nitride, aluminum oxide, or hafnium oxide.

[0061] Next, referring to FIG. 5g, a process of patterning the anti-reflection material layer 450L is performed. In this embodiment, the patterning process of the anti-reflective material layer 450L is performed by an anisotropic etching process (e.g., a dry etching process), and the process of forming holes h in the anti-reflective material layer 450L in the active pixel region APR and the process of forming a passivation layer PL in the pad region PDR are both performed. In the step of forming the hole h in the anti-reflection layer 450, the anti-reflection material layer portion is removed from the bottom of the pad opening OP while the passivation layer PL remains on the sidewall of the pad opening OP.

[0062] As described above, in this step, the upper end portion of the passivation layer PL is partially etched, and the passivation layer PL has a rounded upper portion R. In this embodiment, a portion 450E of the anti-reflection material layer 450L also remains in at least one region of the peripheral region (for example, the optical black region OB and the connection region CR). Furthermore, the portion of the protective film 330 exposed in the pad opening OP is removed, thereby exposing the bonding pad 390 through the pad opening OP.

[0063] The pad openings employed in this embodiment may have various shapes. The pad opening (also called an "edge-open pad opening") is configured to expose one edge of the image sensor, as shown in FIGS.

[0064] 6 and 7 are cross-sectional views showing a schematic configuration of an image sensor according to another embodiment of the present invention. First, referring to FIG. 6, the image sensor 10B according to this embodiment can be understood to have a similar structure to the image sensor 10 shown in FIGS. 1 to 3 (particularly FIG. 3), except that the pad opening OE is exposed toward one edge of the first surface 110E of the first substrate 110, no material layer for an anti-reflection layer remains in the peripheral region, and the meta-optical structure 400A is realized as a single-layer nanoprism pattern NP. Furthermore, unless otherwise specifically described, the components of this embodiment can be understood by reference to the descriptions of the same or similar components of the image sensor 10 shown in FIGS.

[0065] In this embodiment, the pad opening OE is exposed toward one edge of the first surface 110E of the first substrate 110 (see FIG. 2). Since the pad region PDR is located at the edge of the image sensor 10B, the pad opening OE can be easily realized in a form exposed toward the edge 110E of the first substrate 110. In this embodiment, the passivation layer PL is formed along the sidewalls of the meta-optical structure 400A and the transparent planarization layer 350 exposed by the pad opening OE.

[0066] The passivation layer PL is formed in the same process as the anti-reflection layer 450 and contains the same material as the anti-reflection layer 450, as in the above-described embodiment. In addition, when forming the hole h in the anti-reflection layer 450, the material layer portion for the anti-reflection layer located at the bottom exposed to the pad opening OE is removed, and in this process, the upper portion of the passivation layer PL has a rounded portion. In this embodiment, unlike the above-described embodiment, the material layer for the anti-reflection layer 450 located in the peripheral region OB / CR is removed. Such removal is accompanied by the formation of holes h in the anti-reflective layer 450 . The meta-optical structure 400A employed in this embodiment is realized by a single layer of nanoprism patterns NP. The refractive index, shape, and height of the nanoprism pattern NP are appropriately designed depending on the wavelength, and in one embodiment, even when a single mold layer 420 is used, the nanoprism pattern NP has a height that ensures the desired phase difference.

[0067] Referring to Figure 7, the image sensor 10C according to this embodiment can be understood to have a structure similar to that of the image sensor 10 shown in Figures 1 to 3 (particularly Figure 3), except that the bonding pad 390 is arranged on the second substrate structure 200, the pad opening OE is exposed toward one edge of the first surface 110E of the first substrate 110, and the meta-optical structure 400A is realized by a single-layer nanoprism pattern NP. Furthermore, unless otherwise specifically described, the components of this embodiment can be understood by reference to the descriptions of the same or similar components of the image sensor 10 shown in FIGS.

[0068] The image sensor 10C according to this embodiment includes a bonding pad 390 disposed on the second substrate structure 200. In this embodiment, the first substrate structure 100 and the second substrate structure 200 are bonded by the first and second bonding structures 190 and 290, similar to the image sensor 10A shown in FIG. Such bonding includes bonding between the metals of the first and second bonding electrodes (195, 295) and bonding between the dielectrics of the first and second bonding insulating layers (191, 291).

[0069] The pad opening OE employed in this embodiment penetrates not only the first substrate structure 100 but also the first and second bonding structures 190 and 290 so that the bonding pad 390 is exposed. Similar to the embodiment described above (see FIG. 6), the pad opening OE is exposed toward one edge of the image sensor 10C. In this embodiment, the pad opening OE exposes not only the sidewalls of the meta-optical structure 400A and the transparent planarization layer 350, but also the sidewalls of the first substrate 110 and the first and second wiring structures (120, 220). A passivation layer PL is formed along the exposed sidewalls. As in the previous embodiment, the passivation layer PL comprises the same material as the anti-reflection layer 450 . For example, the passivation layer PL may comprise silicon nitride, aluminum oxide, or hafnium oxide. The upper end portion of the passivation layer PL has a rounded portion R.

[0070] 8a to 8d are cross-sectional views illustrating steps in a method for manufacturing the image sensor 10B of FIG. 6A and 6B show a step of forming the pad opening OE and the passivation layer PL in the method of manufacturing the image sensor 10B. Referring to FIG. 8a, a meta-optical structure 400A is formed on the light incident surface side of the image sensor 10B, i.e., on the transparent planarization layer 250, and the stack (410, 420, 431, 432) of the meta-optical structure 400A is removed in the pad region PDR to expose the bonding pad 390.

[0071] In this process, a portion of the stack (410, 420, 431, 432) of the meta-optical structure 400A is removed from the area where the bonding pad 390 is located to one edge of the first substrate 110, thereby forming a primary opening OE' for an edge-open type pad opening. These stacks (410, 420, 431, 432) may be inorganic material layers such as silicon oxide or aluminum oxide, and are removed by a dry etching process.

[0072] Next, referring to FIG. 8b, the transparent planarization layer 350 exposed in the primary opening OE' is removed to form an edge-open pad opening OE. In this embodiment, the transparent planarization layer 350 contains an organic material, so the exposed areas can be removed by a simple process such as an ashing process. As described above, the edge-open type pad opening OE introduced in this embodiment is performed through two removal processes, namely, a dry etching process and an ashing process.

[0073] Next, referring to FIG. 8c, an anti-reflective material layer 450L is formed on the top surface of the meta-optical structure 400A and on the surface exposed by the pad opening OE. The anti-reflective material layer 450L is deposited relatively conformally on the top surface of the meta-optical structure 400A as well as on the surface exposed by the pad opening OP. Next, referring to FIG. 8d, an anisotropic etching process (eg, a dry etching process) is used to form holes h in the anti-reflection material layer 450L in the active pixel region APR, and simultaneously form a passivation layer PL in the pad region PDR.

[0074] In the process of forming the hole h in the anti-reflection layer 450, the anti-reflection material layer is removed from the bottom of the pad opening OE while the passivation layer PL remains on the sidewall of the pad opening OE. In this embodiment, the anti-reflection material layer 450L is removed in the peripheral area (eg, the optical black area OB and the connection area CR). Furthermore, the portion of the protective film 330 exposed in the pad opening OE above the bonding pad 390 is removed to expose the bonding pad 390.

[0075] 9 to 11 are cross-sectional views showing the schematic configuration of image sensors (10D, 10E, 10F) according to other embodiments of the present invention. The embodiments shown in FIGS. 9-11 provide a way to reduce the interface between the dielectric layers of the meta-optical structure 400 exposed on the sidewalls of the pad opening OP.

[0076] Referring to Figure 9, the image sensor 10D according to this embodiment can be understood to have a similar structure to the image sensor 10 shown in Figures 1 to 3 (particularly Figure 3), except that the first mold layer 421 has an edge portion 421E spaced apart from the sidewall of the pad opening OP, the second mold layer 422 covers the edge portion 421E of the first mold layer 421, and the anti-reflection layer 450A is provided only in the active pixel region APR without any holes, and the passivation layer is omitted. Furthermore, unless otherwise specifically described, the components of this embodiment can be understood by reference to the descriptions of the same or similar components of the image sensor 10 shown in FIGS.

[0077] In this embodiment, a first mold layer 421 is disposed on the base dielectric layer 410, and in the pad region PDR, the first mold layer 421 has an edge portion 421E spaced apart from the sidewall of the pad opening OP. Edge portion 421E of first mold layer 421 has a slightly inclined surface due to a planarization process such as CMP for obtaining first nanoprism pattern NP1 (see FIG. 12c).

[0078] The second mold layer 422 is disposed on the first mold layer 421 and covers the edge portion 421E of the first mold layer 421 in the pad region PDR. As a result, the second mold layer 422 is extended to the pad opening OP and provided on the sidewall of the pad opening OP, while the first mold layer 421 is not exposed to the sidewall of the pad opening OP. As a result, compared to the embodiment of FIG. 3 having a similar meta-optical structure 400, the interface between the first and second mold layers (421, 422) is not exposed at the sidewalls of the pad opening OP. As described above, according to this embodiment, the interface between the dielectric layers on the sidewall of the pad opening OP is reduced, thereby reducing the risk of defects such as peeling due to the interface.

[0079] The anti-reflection layer 450A can be implemented in various forms. In this embodiment, the anti-reflection layer 450A is provided only on the active pixel region APR without any holes. Although the passivation layer is omitted in this embodiment, in one embodiment, the passivation layer can be combined with a method for reducing the interface between dielectric layers to more effectively prevent defects occurring at the pad opening OP (see Figures 10 and 11).

[0080] Referring to FIG. 10, the image sensor 10E according to this embodiment can be understood to have a similar structure to the image sensor 10A shown in FIG. 4, except that the first mold layer 421 has an edge portion 421E spaced apart from the sidewall of the pad opening OP, and the second mold layer 422 covers the edge portion 421E of the first mold layer 421. Furthermore, unless otherwise specified, the components of this embodiment can be understood by referring to the descriptions of the same or similar components of the image sensor 10 shown in Figures 1 to 3 and the image sensor 10A shown in Figure 4.

[0081] The image sensor 10E according to this embodiment includes bonding pads 390 disposed on the second substrate structure 200, similar to the image sensor 10A shown in FIG. In addition, a pad opening OP penetrates a portion of the first substrate structure 100 and the second wiring structure 220 so that the bonding pad 390 is exposed. The first and second substrate structures 100 and 200 employed in this embodiment are bonded by first and second bonding structures 190 and 290, similar to the image sensor 10A shown in FIG. Such bonding includes intermetallic bonding of the first and second bonding electrodes (195, 295) and interdielectric bonding of the first and second bonding insulating layers (191, 291).

[0082] Similar to the embodiment described above (see FIG. 9), the first mold layer 421 has an edge portion 421E on the base dielectric layer 410 that is spaced apart from the sidewall of the pad opening OP. Second mold layer 422 is on first mold layer 421 and covers edge portion 421 E of first mold layer 421 . This prevents the interface between the first and second mold layers (421, 422) from being exposed at the sidewalls of the pad opening OP, as compared to the embodiment of FIG. 4 having a similar meta-optical structure 400. In this manner, also in this embodiment, by reducing the interface between the dielectric layers on the sidewall of the pad opening OP, it is possible to reduce the risk of defects such as peeling due to the interface.

[0083] The image sensor 10E according to this embodiment includes a passivation layer PL disposed on the sidewall of the pad opening OP. The other interfaces of the meta-optical structure 400 and the sides of the transparent planarization layer 350 are protected by a passivation layer PL. This passivation layer PL is formed, similarly to the passivation layer PL described with reference to FIG. 4, by utilizing the process of forming the anti-reflection layer 450, particularly the process of forming the holes h. A material layer 450D similar to the passivation layer PL also remains on the sidewall of the meta-optical structure 400 employed in this embodiment. Like the edge portion 421E of the first mold layer 421, the edge portion 422E of the second mold layer 422 also has sloped sidewalls that are subject to a planarization process such as CMP, so that the material layer 450D located on the sidewall of the meta-optical structure 400 remains at a thickness thinner than the thickness of the passivation layer PL.

[0084] Referring to Figure 11, the image sensor 10F according to this embodiment can be understood to have a similar structure to the image sensor 10D shown in Figure 9, except that the pattern material 440R remains on the edge portion 421E of the first mold layer 421, the edge portion of the meta-optical structure 400 is adjacent to the pad opening OP, a hole h is formed in the anti-reflection layer 500, and a passivation layer PL is formed in the pad opening OP. Furthermore, unless otherwise specified, the components of this embodiment can be understood by referring to the descriptions of the same or similar components of the image sensor 10 shown in Figures 1 to 3 and the image sensor 10D shown in Figure 9.

[0085] The pattern material 440R remains on the edge portion 421E of the first mold layer 421. The residual pattern material 440R is obtained when a portion of the pattern material layer 440L (see FIG. 12b) deposited on the nearly vertical edge portion 421E' of the first molding portion 421 remains on the sloping edge portion 421E of the first molding portion 421 even after the CMP process. Thus, residual pattern material 440R contains the same material as first nanoprism pattern NP1.

[0086] The edge locations of the meta-optical structure 400 can be varied in many ways. In this embodiment, the edge of the meta-optical structure 400 is located adjacent to the pad opening OP. The position of the edge of the meta-optical structure 400 is determined by the position of the edge 421 E of the first molding portion 421 . The edge portion 421E of the first molding portion 421 may be located in the pad region PDR, but in one embodiment, may be located in the connection region CR.

[0087] The image sensor 10F according to this embodiment includes a passivation layer PL disposed on the sidewall of the pad opening OP. The other interfaces of the meta-optical structure 400 and the sides of the transparent planarization layer 350 are protected by a passivation layer PL. This passivation layer PL is formed using the process for forming the anti-reflection layer 450, particularly the process for forming the holes h, in the same manner as the passivation layer PL described with reference to FIG. A material layer 450D similar to the passivation layer PL also remains on the sloped sidewalls of the meta-optical structure 400 employed in this embodiment. The material layer 450D located on the sloped sidewalls of the meta-optical structure 400 may remain with a thickness thinner than the thickness of the passivation layer PL. In this manner, in the process of forming the meta-optical structure 400, the lower dielectric layer is formed at a distance from the pad opening OP, and the upper dielectric layer is formed to cover the distanced portion of the lower dielectric layer, thereby reducing the interface of the dielectric layer exposed from the sidewall of the pad opening OP.

[0088] 12a to 12e are cross-sectional views illustrating the steps of a method for manufacturing the image sensor 10D of FIG. Referring to FIG. 12a, the first mold layer 421 is etched using the first etch stop film 431 to form a hole pattern H1 for the first nanoprism pattern NP1.

[0089] In the etching process for the hole pattern H1, the first mold layer 421 is partially removed in the pad region PDR to form a first opening OE1 that is exposed toward one edge of the first substrate 110. The first opening OE1 is formed at a sufficient distance from the area where the edge portion 421E' of the first mold layer 421 vertically overlaps the bonding pad 390. The edge portion 421E' obtained in this step has almost vertical side surfaces similar to the hole pattern H1.

[0090] Next, referring to FIG. 12b, a pattern material layer 440L is formed on the first mold layer 421 to fill the hole pattern H1. The conductive layer is formed so as to fill the first opening OE1 located in the pad region PDR. For example, the pattern material layer 440L can include transparent inorganic materials such as titanium oxide, silicon nitride, niobium oxide, tantalum oxide, aluminum oxide, and hafnium oxide.

[0091] Next, referring to FIG. 12c, a planarization process such as CMP is performed to form a first nanoprism pattern NP1 defined by the hole pattern H1. In the process of removing the portion of the pattern material layer 440L on the first mold layer 421, the portion of the pattern material layer 440L located in the first opening OE1 is also removed. The portion of the pattern material layer 440L located in the first opening OE1 is adjacent to the edge, even though it is located on the base dielectric layer at a slightly lower level, and is therefore removed together with the portion of the pattern material layer 440L on the first mold layer 421 during the CMP process. In one embodiment, the pattern material layer (see "440R" in FIG. 11) partially remains at the edge of the first mold layer 421 after the CMP process.

[0092] Next, referring to FIG. 12d, second mold layer 422 having second nanoprism pattern NP2 is formed on first mold layer 421 having first nanoprism pattern NP1. Also in this step, a second opening OE2 is formed in the second mold layer 422 located on the base dielectric layer 410 in the pad region PDR. Like the first openings OE1, the second openings OE2 are also formed in the second mold layer 422 during the process of forming a hole pattern for the second nanoprism pattern NP2. Similar to the first opening OE1, the second opening OE2 also has a structure that includes a region overlapping with the bonding pad 390 and is exposed toward the edge.

[0093] Next, referring to FIG. 12e, an anti-reflection layer 450A is formed in the active pixel region APR, and a pad opening OP connected to the bonding pad 390 is formed in the pad region PDR. In this embodiment, the antireflection layer 450A is formed before the pad opening OP is formed, unlike the above-described embodiments (FIGS. 3 and 6). In this embodiment, a pad opening OP is formed within the second opening OE2 and extends through the base dielectric layer 410 and the transparent planarization layer 340 of the meta-optical structure 400. The remaining protective film 330 protects the bonding pad 390 in the subsequent passivation layer forming process. A step of patterning the anti-reflection material layer 450L is carried out. Furthermore, the portion of the protective film 330 exposed in the pad opening OP is removed, thereby exposing the bonding pad 390 through the pad opening OP.

[0094] 13 and 14 are cross-sectional views showing the schematic configuration of image sensors (10G, 10H) according to other embodiments of the present invention. The embodiment shown in FIGS. 13 and 14 provides a method for preventing the transparent planarization layer 350 from being exposed on the sidewall of the pad opening OP even without a passivation layer.

[0095] Referring to FIG. 13, the image sensor 10G according to this embodiment can be understood to have a similar structure to the image sensor 10 shown in FIGS. 1 to 3 (particularly FIG. 3), except that the transparent planarization layer 350 has an edge portion 350E spaced from the pad opening OP, the meta-optical structure 400B covers the edge portion 350E of the transparent planarization layer 350, the meta-optical structure 400B has a new structure, and an anti-reflection layer 450B is provided on the upper surface of the meta-optical structure 400B, and the passivation layer is omitted. Furthermore, unless otherwise specifically described, the components of this embodiment can be understood by reference to the descriptions of the same or similar components of the image sensor 10 shown in FIGS.

[0096] The transparent planarization layer 350 covers the color filter 340, the light-shielding filter layer 340L, and the first connecting structure 360 ​​on the first surface 110a of the first substrate 110, and provides a flat upper surface. The transparent planarization layer 350 is formed only in the active pixel area APR, the optical black area OB, and the connection area CR. In one embodiment, the transparent planarization layer 350 may extend to a portion of the pad region PDR.

[0097] In this embodiment, the transparent planarization layer 350 has an edge portion 350E spaced apart from the pad opening OP, and the meta-optical structure 400B covers the edge portion 350E of the transparent planarization layer 350. In one embodiment, the transparent planarization layer 350 may include an organic material such as an acrylic resin, a styrene resin, a polyimide resin, or a siloxane resin. As such, unlike the dielectric layer of the meta-optical structure 400B, the transparent planarization layer 350 contains an organic material, in which case undercuts may occur during the process of forming the pad opening OP. However, in this embodiment, the edge portion 350E of the transparent planarization layer 350 is covered by the base dielectric layer 410 and the mold layer 420', thereby preventing exposure of the transparent planarization layer 350 on the sidewalls of the pad opening OP.

[0098] The meta-optical structure 400B employed in this embodiment has a new structure. Meta-optical structure 400B includes a base dielectric layer 410, a nanoprism pattern NP' on base dielectric layer 410, and a mold layer 420' disposed on base dielectric layer 410 and covering nanoprism pattern NP'. In this embodiment, unlike the above-described embodiments (e.g., the processes of Figures 5a to 5c), an etching stop layer 431 and a pattern material layer are sequentially formed on a base dielectric layer 410, and the pattern material layer is etched using the etching stop layer 431 to form a nanoprism pattern NP'. Next, a mold layer 420' is formed to cover the nanoprism pattern NP', thereby forming the meta-optical structure 400B employed in this embodiment.

[0099] The anti-reflection layer 450B is formed without holes in the active pixel region APR, the peripheral region OB / CR, and the pad region PDR. A pad opening OP is formed through the anti-reflective layer 450B and the meta-optical structure 400B. In this embodiment, the passivation layer is omitted, but in one embodiment, the passivation layer can be combined with a method for reducing the interface between dielectric layers to more effectively prevent defects occurring at the pad opening OP (see FIG. 14).

[0100] Referring to FIG. 14, the image sensor 10H according to this embodiment can be understood to have a similar structure to the image sensor 10A shown in FIG. 4, except that the transparent planarization layer 350 has an edge portion 350E spaced apart from the sidewall of the pad opening OP, the meta-optical structure 400B covers the edge portion 350E of the transparent planarization layer 350, and the meta-optical structure 400B has a new structure. Furthermore, unless otherwise specified, the components of this embodiment can be understood by referring to the descriptions of the same or similar components of the image sensor 10 shown in Figures 1 to 3 and the image sensor 10A shown in Figure 4.

[0101] The image sensor 10E according to this embodiment includes bonding pads 390 disposed on the second substrate structure 200, similar to the image sensor 10A shown in FIG. Additionally, a pad opening OP penetrates a portion of the first substrate structure 100 and the second wiring structure 220 to expose the bonding pad 390 . The first and second substrate structures 100 and 200 employed in this embodiment are bonded by first and second bonding structures 190 and 290, similar to the image sensor 10A shown in FIG. Such bonding includes intermetallic bonding of the first and second bonding electrodes (195, 295) and interdielectric bonding of the first and second bonding insulating layers (191, 291).

[0102] In this embodiment, the transparent planarization layer 350 covers the color filter 340, the light-shielding filter layer 340L, and the first connecting structure 360 ​​on the first surface 110a of the first substrate 110, and provides a flat upper surface. Similar to the embodiment described above (see FIG. 13), the transparent planarization layer 350 has an edge portion 350E spaced apart from the pad opening OP, and the meta-optical structure 400B covers the edge portion 350E of the transparent planarization layer 350. In this manner, the edge portion 350E of the transparent planarization layer 350 made of an organic material is covered by the base dielectric layer 410 and the mold layer 420', thereby preventing the transparent planarization layer 350 from being exposed at the sidewall of the pad opening OP.

[0103] The meta-optical structure 400B employed in this embodiment includes, similar to the embodiment described above (see FIG. 13), a base dielectric layer 410, a nanoprism pattern NP′ on the base dielectric layer 410, and a mold layer 420′ disposed on the base dielectric layer 410 and covering the nanoprism pattern NP′. The image sensor 10H according to this embodiment includes a passivation layer PL disposed on the sidewall of the pad opening OP. The other interfaces of the meta-optical structure 400 and the sides of the transparent planarization layer 350 are protected by a passivation layer PL. This passivation layer PL is formed using the process of forming the anti-reflection layer 450, particularly the process of forming the holes h, in the same manner as the passivation layer PL described with reference to FIG.

[0104] A material layer 450D similar to the passivation layer PL also remains on the sidewall of the meta-optical structure 400B employed in this embodiment. Like the edge portion 421E of the first mold layer 421, the edge portion 422E of the second mold layer 422 also has sloped sidewalls that are subject to a planarization process such as CMP, so that the material layer 450D located on the sidewall of the meta-optical structure 400 remains at a thickness thinner than the thickness of the passivation layer PL.

[0105] 15a to 15f are cross-sectional views illustrating steps in a manufacturing method for the image sensor 10G of FIG. Referring to FIG. 15a, a transparent planarization layer 350 having an edge portion 350E spaced apart from the pad opening OP is formed on the first surface 110a of the first substrate 110.

[0106] First, the transparent planarization layer 350 is formed on the first surface 110a of the first substrate 110 so as to cover the color filter 340, the light-shielding filter layer 340L, and the first and second connecting structures (360, 370). The transparent planarization layer 350 is formed over the active pixel region APR, the optical black region OB, the connection region CR, and the pad region PDR, thereby having a flat upper surface. Next, in the pad region PDR, the transparent planarization layer 350 is partially removed to form a first opening OE1' that exposes one edge of the first substrate 110.

[0107] Next, referring to FIG. 15b, a base dielectric layer 410 is formed, and a nanoprism pattern NP' is formed on the base dielectric layer 410. In this process, an etching stop layer 431 and a pattern material layer are sequentially formed on a base dielectric layer 410, and the pattern material layer is etched using the etching stop layer 431 to form the nanoprism pattern NP'.

[0108] Next, referring to FIG. 15c, a mold layer 420′ is formed to cover the nanoprism pattern NP′ to form the meta-optical structure 400B employed in this embodiment, and an anti-reflection layer 450B is further formed on the meta-optical structure 400B. The anti-reflection layer 450B employed in this embodiment is formed without holes in the active pixel region APR, the peripheral region OB / CR, and the pad region PDR. Next, a pad opening OP is formed through the anti-reflection layer 450B and the meta-optical structure 400B. The specific configurations of the above-described embodiments may be realized in a combined form of two or more embodiments, unless otherwise specified. Image sensors according to embodiments in which the above-described unique configurations are combined are illustrated in FIGS.

[0109] 16 and 17 are cross-sectional views showing a schematic configuration of an image sensor according to another embodiment of the present invention. Referring to Figure 16, the image sensor 10I according to this embodiment includes a configuration for introducing a passivation layer PL on the sidewall of the pad opening OP (see Figure 3), a configuration for preventing exposure of the transparent planarization layer 350 on the sidewall of the pad opening OP (see Figure 13), and a configuration for preventing exposure of the interface between the first and second mold layers (421, 422) of the meta-optical structure 400 exposed on the sidewall of the pad opening OP (see Figures 9 and 11). Unless otherwise specified, the components of this embodiment can be understood with reference to the descriptions of the same or similar components of the image sensor 10 shown in Figures 1 to 3 and the image sensors (10D, 10F, 10G) shown in Figures 9, 11, and 13.

[0110] First, the transparent planarization layer 350 adopted in this embodiment has an edge portion 350E spaced apart from the pad opening OP, similar to the above-described embodiment (see FIG. 13), and the meta-optical structure 400 covers the edge portion 350E of the transparent planarization layer 350. The edge portion 350E of the transparent planarization layer 350, which is easily damaged, is covered by the base dielectric layer 410 and the first and second mold layers (421, 422), thereby preventing the transparent planarization layer 350 from being exposed at the sidewall of the pad opening OP. In addition, the meta-optical structure 400 adopted in this embodiment includes, similar to the above-mentioned embodiments (see Figures 9 and 11), a first mold layer 421 having an edge portion 421E spaced apart from the sidewall of the pad opening OP on the base dielectric layer 410, and a second mold layer 422 arranged on the first mold layer and covering the edge portion 421E of the first mold layer 421.

[0111] Edge portion 421E of first mold layer 421 has a slightly inclined surface due to a planarization process such as CMP for obtaining first nanoprism pattern NP1. In this embodiment, the second mold layer covers the edge portion 421E of the first mold layer 421 and extends onto the base dielectric layer area adjacent the pad opening. In this way, the interface between the first mold layer 421 and the second mold layer 422 is not exposed to the sidewall of the pad opening OP. The image sensor 10I according to this embodiment includes a passivation layer PL disposed on the sidewall of the pad opening OP. The edges of the meta-optical structure 400 and the sides of the base dielectric layer 410 are protected by a passivation layer PL. This passivation layer PL is formed using the process of forming the anti-reflection layer 450, particularly the process of forming the holes h, in the same manner as the passivation layer PL described with reference to FIG.

[0112] Referring to FIG. 17, the image sensor 10J according to this embodiment can be understood to have a similar structure to the image sensor 10I shown in FIG. 16, except that the bonding pad 390 is arranged on the second substrate structure 200 and the pad opening OP penetrates the first substrate structure 100, the first substrate structure 100 and the second substrate structure 200 are connected by metal-dielectric hybrid bonding instead of a connection structure (symbols 360 and 370 in FIG. 16) which is a through-structure, and the pattern material 440R remains on the edge portion 421E of the first mold layer 421.

[0113] The image sensor 10J according to this embodiment includes a configuration for introducing a passivation layer PL on the sidewall of the pad opening OP (see FIG. 4), a configuration for preventing exposure of the transparent planarization layer 350 on the sidewall of the pad opening OP (see FIG. 14), and a configuration for preventing exposure of the interface between the first and second mold layers (421, 422) of the meta-optical structure 400 exposed on the sidewall of the pad opening OP (see FIG. 10). Unless otherwise specified, the components of this embodiment can be understood by referring to the descriptions of the same or similar components of the image sensors (10A, 10E, 10H) shown in FIGS. 4, 10, and 14, as well as the image sensor 10I shown in FIG. 16.

[0114] The image sensor 10J according to this embodiment, like the image sensor 10A shown in FIG. 4, includes a bonding pad 390 arranged on the second substrate structure 200, and a pad opening OP penetrates a portion of the first substrate structure 100 and the second wiring structure 220 to expose the bonding pad 390. The first and second substrate structures 100 and 200 employed in this embodiment are bonded by first and second bonding structures 190 and 290, similar to the image sensor 10A shown in FIG. Such bonding includes intermetallic bonding of the first and second bonding electrodes (195, 295) and interdielectric bonding of the first and second bonding insulating layers (191, 291).

[0115] The transparent planarization layer 350 employed in this embodiment has an edge portion 350E spaced apart from the pad opening OP, similar to the embodiment described above (see FIG. 14), and the meta-optical structure 400 covers the edge portion 350E of the transparent planarization layer 350. This makes it possible to prevent the transparent planarizing layer 350 from being exposed on the sidewall of the pad opening OP. The meta-optical structure 400 employed in this embodiment includes, similarly to the above-described embodiment (see FIG. 10), a first mold layer 421 on a base dielectric layer 410 having an edge portion 421E spaced apart from the sidewall of the pad opening OP, and a second mold layer 422 arranged on the first mold layer and covering the edge portion 421E of the first mold layer 421. As a result, the interface between the first mold layer 421 and the second mold layer 422 is not exposed to the side wall of the pad opening OP.

[0116] The image sensor 10J according to this embodiment includes a passivation layer PL disposed on the sidewall of the pad opening OP, similar to the embodiment described above (see FIG. 4). The edges of the meta-optical structure 400 and the sides of the base dielectric layer 410 are protected by a passivation layer PL. This passivation layer PL is formed using the process of forming the anti-reflection layer 450, particularly the process of forming the holes h, in the same manner as the passivation layer PL described with reference to FIG. A material layer 450D similar to the passivation layer PL also remains on the sidewall of the meta-optical structure 400 employed in this embodiment. Like the edge portion 421E of the first mold layer 421, the edge portion 422E of the second mold layer 422 also has sloped sidewalls that are subject to a planarization process such as CMP, so that the material layer 450D located on the sidewall of the meta-optical structure 400 remains at a thickness thinner than the thickness of the passivation layer PL.

[0117] In this embodiment, the residual pattern material 440R is located at the edge portion 421E of the first mold layer 421. The residual pattern material 440R is obtained when a portion of the pattern material layer (440L in FIG. 12b) deposited on the nearly vertical edge portion 421E of the first molding portion 421 remains on the sloping edge portion 421E of the first molding portion 421 even after the CMP process. Thus, residual pattern material 440R contains the same material as first nanoprism pattern NP1. As illustrated in FIGS. 16 and 17, the above-described embodiments may be embodied in two or more various combinations unless otherwise stated.

[0118] The present invention is not limited to the above-described embodiment, and various modifications can be made without departing from the technical scope of the present invention. [Explanation of symbols]

[0119] 10 Image Sensor 100 1st substrate structure 110 First board 112 Element isolation pattern 120 1st wiring structure 121 First inter-wiring insulating layer 125 1st wiring 150 pixel isolated pattern 200 Second board structure 210 Second board 215 Logic Elements 220 2nd wiring structure 221 Second inter-wiring insulating layer 225 2nd wiring 300 Front optical structure 310 Surface insulating layer 320 grid pattern 330 Protective film 340 Color Filter 350 Transparent flattening layer 340L Light-shielding filter layer 360 First connection structure 361 First conductive layer 362 First Connection Layer 363 First Separation Pattern 365 First Capping Pattern 370 Second connection structure 371 Second conductive layer 372 Second Connection Layer 373 Second Separation Pattern 375 Second Capping Pattern 371 Second conductive layer 380 bias contact plug 390 Bonding Pad 400, 400B Meta-Optical Structure 410, 421, 422 Dielectric layers 431 First etching stop film 432 Second etching stop film 433 Third etching stop film 450, 450B Anti-reflection layer APR Active Pixel Area CR Connection Area DX Dummy Pixel FD Floating diffusion region NP1 First nanoprism pattern NP2 Second nanoprism pattern NPD dummy photoelectric conversion area OB Optical Black Area OB / CR peripheral area OP pad opening PD photoelectric conversion region PDR Pad Area PL passivation layer PX pixels PX' Optical Black Pixel TG Transfer Gate

Claims

1. An image sensor, a laminated structure including an active pixel area in which a plurality of pixels are defined, and a pad area disposed on at least one side of the active pixel area; The laminated structure is a first substrate having a first surface and a second surface opposite the first surface, the first substrate including a photoelectric conversion region for each of the plurality of pixels; a meta-optical structure including: a plurality of dielectric layers disposed on the first surface of the first substrate; and a nanoprism pattern arranged in at least one of the plurality of dielectric layers in the active pixel area, the plurality of dielectric layers having pad openings exposing bonding pads in the pad area; a passivation layer covering the plurality of dielectric layer portions provided on sidewalls of the pad opening; a second substrate disposed on the second surface of the first substrate, on which logic elements for driving the plurality of pixels are formed.

2. The image sensor of claim 1 , wherein the plurality of dielectric layers includes a base dielectric layer and at least one mold layer having a nanoprism pattern.

3. The image sensor of claim 2 , wherein the meta-optical structure further comprises an anti-reflection layer on the at least one mold layer.

4. The image sensor of claim 3 , wherein the passivation layer comprises the same material as the anti-reflection layer.

5. 5. The image sensor of claim 4, wherein the anti-reflection layer includes a plurality of holes, and the passivation layer has a rounded top edge.

6. The at least one mold layer comprises: a first mold layer having a first nanoprism pattern; and a second mold layer disposed on the first mold layer, the second mold layer having a second nanoprism pattern.

7. the first mold layer has an edge portion spaced apart from a sidewall of the pad opening; The image sensor of claim 6 , wherein the second mold layer covers the edge portion of the first mold layer.

8. a transparent planarization layer disposed between the first surface of the first substrate and the meta-optical structure, the transparent planarization layer having an edge spaced apart from the pad opening; The image sensor of claim 1 , wherein an edge portion of the transparent planarization layer is covered by the plurality of dielectric layers.

9. The image sensor of claim 8 , wherein the transparent planarization layer comprises an organic material.

10. The image sensor of claim 1 , wherein the pad opening is exposed toward an edge of the first substrate.

11. The image sensor of claim 1 , wherein the bonding pad is disposed on the first surface of the first substrate.

12. the pad opening extends through the first substrate in the pad region; the bonding pad is disposed in an area of ​​the second substrate exposed by the pad opening; The image sensor of claim 1 , wherein the passivation layer extends to cover a sidewall exposed by the pad opening of the first substrate.

13. An image sensor, a laminated structure including an active pixel area in which a plurality of pixels are defined and a pad area disposed on at least one side of the active pixel area; The laminated structure is a first substrate having a first surface and a second surface opposite the first surface, the first substrate including a photoelectric conversion region for each of the plurality of pixels; a meta-optical structure including: a plurality of dielectric layers disposed on the first surface of the first substrate; and a nanoprism pattern arranged in at least one of the plurality of dielectric layers in the active pixel area, the plurality of dielectric layers having pad openings exposing bonding pads in the pad area; a second substrate disposed on a second surface of the first substrate and having logic elements formed thereon for driving the plurality of pixels; The plurality of dielectric layers include: a first mold layer having a first nanoprism pattern; a second mold layer having a second nanoprism pattern on the first mold layer; the first mold layer has a first edge spaced from a sidewall of the pad opening; The image sensor, wherein the second mold layer covers the first edge portion of the first mold layer.

14. a material identical to the material of the first nanoprism pattern remains on a first edge portion of the first mold layer; The image sensor of claim 13 , wherein the second mold layer covers the first edge portion of the first mold layer together with the remaining material.

15. 14. The image sensor of claim 13, wherein the second molding layer has a second edge portion spaced apart from a sidewall of the pad opening.

16. a passivation layer covering the plurality of dielectric layer portions provided on the sidewalls of the pad opening; the meta-optical structure further includes an anti-reflection layer disposed on the second mold layer; The image sensor of claim 13 , wherein the passivation layer comprises the same material as the anti-reflection layer.

17. An image sensor, a laminated structure including an active pixel area in which a plurality of pixels are defined and a pad area disposed on at least one side of the active pixel area; The laminated structure is a first substrate having a first surface and a second surface opposite the first surface, the first substrate including a photoelectric conversion region for each of the plurality of pixels; a meta-optical structure including: a plurality of dielectric layers disposed on the first surface of the first substrate; and a nanoprism pattern arranged in at least one of the plurality of dielectric layers in the active pixel region, wherein the plurality of dielectric layers have pad openings exposing bonding pads in the pad region; a transparent planarization layer disposed between the first surface of the first substrate and the meta-optical structure, the transparent planarization layer having an edge spaced apart from a sidewall of the pad opening; wherein the edge portion of the transparent flattening layer is covered with the plurality of dielectric layers; a second substrate disposed on a second surface of the first substrate, on which logic elements for driving the plurality of pixels are formed.

18. The plurality of dielectric layers include: a base dielectric layer on the transparent planarization layer; a first mold layer disposed on the base dielectric layer and including a first nanoprism pattern in the active pixel area; a second mold layer disposed on the first mold layer and including a second nanoprism pattern corresponding to the first nanoprism pattern; the edge portion of the transparent planarization layer is covered by the base dielectric layer; 18. The image sensor of claim 17, wherein the base dielectric layer has a portion exposed on a sidewall of the pad opening.

19. the first mold layer has a first edge spaced from the pad opening; The image sensor of claim 18 , wherein the second mold layer covers the first edge portion of the first mold layer.

20. the meta-optical structure further includes an anti-reflection layer disposed on the second mold layer; 20. The image sensor of claim 18, further comprising a passivation layer covering the portions of the dielectric layer provided on the sidewalls of the pad opening and including a material identical to that of the anti-reflection layer.

Images