Image sensor

Abstract

To provide an image sensor capable of improving quality and productivity.SOLUTION: In an image sensor containing: a substrate 110 including a first region (a sensor array region SAR) and a second region (a connection region CR and a pad region PR); and a photoelectric conversion layer PD in the first region, a pixel separation pattern 120 which is extended from a first surface 110a to a second surface 110b, and separates a unit pixel, contains: a pixel separation filling film 125; a dummy pixel separation pattern 320 in which one part of a pixel separation recess 120R defined by the pixel separation spacer film 121 is embedded, which is extended from the first surface to the second surface in the second region, and in which at least one part of the dummy pixel separation recess 320R is embedded; and a contact 147 that connects a dummy pixel separation filling film 325 and a wiring. A height H1 from the first surface to a bottom surface of the pixel separation filling film is larger than that to a bottom surface 325BS of the dummy pixel separation filling film.SELECTED DRAWING: Figure 5

Description

Technical Field

[0001] The present invention relates to an image sensor.

Background Art

[0002] An image sensor is one of semiconductor devices that convert optical information into electrical signals. Such image sensors may include charge-coupled device (CCD) image sensors and complementary metal-oxide semiconductor (CMOS) image sensors.

[0003] An image sensor is configured in a package form. At this time, the package can be configured to protect the image sensor and at the same time allow light to be incident on the photo receiving surface or sensing area of the image sensor.

[0004] Recently, a backside illumination (BSI) image sensor has been studied in which incident light is irradiated through the back surface of a semiconductor substrate so that pixels formed in the image sensor have improved light reception efficiency and sensitivity.

Summary of the Invention

Problems to be Solved by the Invention

[0005] The technical problem to be solved by the present invention is to provide an image sensor with improved quality and productivity.

[0006] The problems to be solved by the present invention are not limited to the problems mentioned above, and other problems not mentioned can be clearly understood by those skilled in the art from the following description.

Means for Solving the Problems

[0007] The aspect-based image sensor of the present invention for achieving the aforementioned technical objectives comprises a substrate including a first region and a second region arranged around the first region, which are opposite to each other; a plurality of unit pixels including a photoelectric conversion layer within the first region of the substrate; a pixel separation pattern in the first region of the substrate extending from the first surface to the second surface of the substrate, separating each unit pixel, comprising a pixel separation spacer film and a pixel separation filling film, wherein the pixel separation filling film fills a portion of the pixel separation recess defined by the pixel separation spacer film; and a dummy pixel extending from the first surface to the second surface of the substrate in the second region of the substrate. A dummy pixel isolation pattern comprising an isolation spacer film and a dummy pixel isolation filling film, wherein the dummy pixel isolation filling film is a dummy pixel isolation pattern that fills at least a portion of the dummy pixel isolation recess defined by the dummy pixel isolation spacer film; a wiring structure on a second surface of a substrate, comprising an interwiring insulating film and a first wiring within the interwiring insulating film; a color filter disposed on the second surface of the substrate; and a first contact directly connected to the dummy isolation filling film and connecting the dummy isolation filling film and the first wiring, wherein the height from the first surface of the substrate to the bottom surface of the pixel isolation filling film is greater than the height from the first surface of the substrate to the bottom surface of the dummy pixel isolation filling film.

[0008] An image sensor according to another aspect of the present invention for achieving the aforementioned technical problems includes a substrate including a first surface and a second surface that are opposite to each other, and including a first region and a second region disposed around the first region; a separation structure having a grid shape, extending from the first surface of the substrate to the second surface of the substrate, and including a separation spacer film and a separation filling film, wherein the separation filling film is a separation structure that fills at least a portion of the separation recess defined by the separation spacer film; a plurality of unit pixels within the first region of the substrate, including a photoelectric conversion layer, wherein the photoelectric conversion layer is a plurality of unit pixels disposed within the substrate separated by the separation structure; a wiring structure on the first surface of the substrate, including an interwiring insulating film and wiring within the interwiring insulating film; a microlens disposed on the second surface of the substrate in the first region of the substrate; a pad disposed on the wiring structure and connected to the wiring; and a contact in the second region of the substrate that is directly connected to the separation filling film and connects the separation filling film and the wiring, wherein in the first region of the substrate, the height from the first surface of the substrate to the bottom surface of the separation filling film is greater than the height from the first surface of the substrate to the bottom surface of the separation filling film in the second region of the substrate.

[0009] An image sensor according to yet another aspect of the present invention for achieving the aforementioned technical problems includes a substrate comprising a first region and a second region arranged around the first region, with a first and second surface that are opposite to each other; a plurality of unit pixels including a photoelectric conversion layer within the first region of the substrate; a pixel separation pattern in the first region of the substrate extending from the first surface to the second surface of the substrate, separating each unit pixel, and comprising a pixel separation spacer film and a pixel separation filling film, wherein the pixel separation filling film fills a portion of the pixel separation recess defined by the pixel separation spacer film; and a dummy pixel in the second region of the substrate extending from the first surface to the second surface of the substrate, comprising a dummy pixel separation spacer film and a dummy pixel separation filling film. A separation pattern comprising a dummy pixel separation filling film, the dummy pixel separation pattern filling at least a portion of the dummy pixel separation recess defined by the dummy pixel separation spacer film, a wiring structure on a first surface of a substrate including an interwiring insulating film and wiring within the interwiring insulating film, a color filter disposed on a second surface of the substrate, a pad disposed on the wiring structure and connected to the wiring, a first connection pattern connected to the underside of the pad, a second connection pattern on the underside of the first connection pattern and connected to the first connection pattern, and contacts directly connected to the dummy separation filling film and connecting the dummy separation filling film to the wiring, wherein the height from the first surface of the substrate to the bottom surface of the pixel separation filling film is greater than the height from the first surface of the substrate to the bottom surface of the dummy pixel separation filling film.

[0010] Specific details of other embodiments are included in the description of the invention and the drawings. [Brief explanation of the drawing]

[0011] [Figure 1a] This is an illustrative block diagram illustrating an image sensor according to several embodiments. [Figure 1b] This is an exemplary circuit diagram illustrating a unit pixel of an image sensor according to several embodiments. [Figure 2]This figure shows a conceptual layout of an image sensor according to several embodiments. [Figure 3] This is an illustrative layout diagram illustrating an image sensor according to several embodiments. [Figure 4] Figure 3 shows cross-sectional views taken along AA, BB, CC, and DD. [Figure 5] This is an enlarged view of region P in Figure 4. [Figure 6] This is an illustrative diagram illustrating an image sensor according to several embodiments. [Figure 7] This is an illustrative diagram illustrating an image sensor according to several embodiments. [Figure 8] This is an illustrative diagram illustrating an image sensor according to several embodiments. [Figure 9] This is an illustrative diagram illustrating an image sensor according to several embodiments. [Figure 10] This is an illustrative diagram illustrating an image sensor according to several embodiments. [Figure 11a] This is a magnified view of the R region in Figure 3. [Figure 11b] This is a magnified view of the R region in Figure 3. [Figure 11c] This is a magnified view of the R region in Figure 3. [Figure 11d] This is a magnified view of the R region in Figure 3. [Figure 12] This figure shows a conceptual layout of an image sensor according to several embodiments. [Figure 13] These are intermediate drawings illustrating a method for manufacturing an image sensor according to several embodiments. [Figure 14] These are intermediate drawings illustrating a method for manufacturing an image sensor according to several embodiments. [Figure 15] These are intermediate drawings illustrating a method for manufacturing an image sensor according to several embodiments. [Figure 16]This is an intermediate drawing for explaining a method of manufacturing an image sensor according to some embodiments. [Figure 17] This is an intermediate drawing for explaining a method of manufacturing an image sensor according to some embodiments. [Figure 18] This is an intermediate drawing for explaining a method of manufacturing an image sensor according to some embodiments. [Figure 19] This is an intermediate drawing for explaining a method of manufacturing an image sensor according to some embodiments. [Figure 20] This is an intermediate drawing for explaining a method of manufacturing an image sensor according to some embodiments. [Figure 21] This is an intermediate drawing for explaining a method of manufacturing an image sensor according to some embodiments. [Figure 22] This is an intermediate drawing for explaining a method of manufacturing an image sensor according to some embodiments.

Embodiments for Carrying Out the Invention

[0012] Hereinafter, an image sensor according to some embodiments will be described with reference to FIGS. 1a to 12.

[0013] FIG. 1a is an exemplary block diagram for explaining an image sensor according to some embodiments. FIG. 1b is an exemplary circuit diagram for explaining a unit pixel of an image sensor according to some embodiments.

[0014] Referring to Figure 1a, an image sensor according to several embodiments includes an active pixel sensor array (10; APS), a row decoder (20; Row Decoder), a row driver (30; Row Driver), a column decoder (40; Column Decoder), a timing generator (50; Timing Generator), a correlated double sampler (60; CDS), an analog-to-digital converter (70; ADS), and an input / output buffer (80; I / O Buffer).

[0015] The active pixel sensor array 10 includes multiple unit pixels arranged in two dimensions and can convert optical signals into electrical signals. The active pixel sensor array 10 can be driven by multiple drive signals from the row driver 30, such as a pixel selection signal, a reset signal, and a charge transfer signal. The electrical signals converted by the active pixel sensor array 10 are then supplied to the correlated duplex sampler 60.

[0016] The row driver 30 can provide the active pixel sensor array 10 with a number of drive signals to drive multiple unit pixels according to the result decoded by the row decoder 20. If the unit pixels are arranged in matrix form, a drive signal is provided for each row.

[0017] The timing generator 50 can provide timing signals and control signals to the row decoder 20 and the column decoder 40.

[0018] The correlated dual sampler (CDS; 60) can receive, hold, and sample electrical signals generated by the active pixel sensor array 10. The correlated dual sampler 60 can sample both a specific noise level and a signal level from the electrical signal, and can output a difference level corresponding to the difference between the noise level and the signal level.

[0019] The analog-to-digital converter (ADC; 70) can convert the analog signal corresponding to the difference level output by the correlated duplex sampler 60 into a digital signal and output it.

[0020] The input / output buffer 80 latches the digital signal, and the latched signal can be sequentially output as a digital signal to the video signal processing unit (not shown) according to the decoding result of the column decoder 40.

[0021] Referring to Figure 1b, each unit pixel may include a photoelectric conversion layer PD, a transfer transistor TG, a floating diffusion region (FD), a reset transistor RG, a source follower transistor SF, and a selection transistor SEL.

[0022] The photoelectric conversion layer PD can generate charge in proportion to the amount of light incident from the outside. The photoelectric conversion layer PD can be coupled with a transfer transistor TG that transmits the generated and stored charge to a floating diffusion region FD. The floating diffusion region FD is a region that converts charge into voltage and has parasitic capacitance, so charge can be stored cumulatively.

[0023] One end of the transfer transistor TG may be connected to the photoelectric conversion layer PD, and the other end of the transfer transistor TG may be connected to the floating diffusion region FD. The transfer transistor TG is formed of a transistor driven by a predetermined bias (e.g., a transmission signal TX). That is, the transfer transistor TG can transfer the charge generated from the photoelectric conversion layer PD to the floating diffusion region FD in accordance with the transmission signal TX.

[0024] The source follower transistor SF amplifies the change in the electrical potential of the floating diffusion region FD, which receives charge transfer from the photoelectric conversion layer PD, and outputs this to the output line. VOUTIt can output to the following. When the source follower transistor SF is turned on, a predetermined electrical potential is provided to the drain of the source follower transistor SF, for example, the power supply voltage V. DD This is transmitted to the drain region of the selection transistor SEL.

[0025] The selection transistor SEL can select a unit pixel to read row by row. The selection transistor SEL consists of a transistor driven by a selection line to which a predetermined bias (e.g., row selection signal SX) is applied.

[0026] The reset transistor RG can periodically reset the floating diffusion region FD. The reset transistor RG consists of a transistor driven by a reset line to which a predetermined bias (e.g., reset signal RX) is applied. When the reset transistor RG turns on in response to the reset signal RX, a predetermined electrical potential, such as the power supply voltage V, is supplied to the drain of the reset transistor RG. DD This is transmitted to the floating diffusion region (FD).

[0027] Figure 2 shows a conceptual layout of an image sensor according to several embodiments.

[0028] Referring to Figure 2, an image sensor according to some embodiments may include a stacked first substrate structure 100 and a second substrate structure 200.

[0029] Multiple unit pixels are arranged in a two-dimensional array structure in a plane containing a first direction X and a second direction Y within the first substrate structure 100. That is, the first substrate structure 100 may include a pixel array. The first direction X and the second direction Y may be perpendicular to each other.

[0030] The second substrate structure 200 may include a logic region, etc. The second substrate structure 200 is located below the first substrate structure 100. The first substrate structure 100 and the second substrate structure 200 can be electrically connected. The second substrate structure 200 can be configured so that pixel signals transmitted from the first substrate structure 100 are transmitted to the logic region of the second substrate structure 200.

[0031] Logic elements are arranged in the logic region of the second substrate structure 200. The logic elements may include circuits for processing pixel signals received from a unit pixel.

[0032] The first substrate structure 100 and the second substrate structure 200 are stacked in the third direction Z. The third direction Z may be perpendicular to the first direction X and the second direction Y.

[0033] Figure 3 is an illustrative layout diagram illustrating an image sensor according to several embodiments.

[0034] Referring to Figure 3, an image sensor according to several embodiments may include a sensor array region (SAR), a linking region (CR), and a pad region (PR).

[0035] The sensor array region SAR may include the region corresponding to the active pixel sensor array 10 in Figure 1a. For example, within the sensor array region SAR, multiple unit pixels are formed that are arranged two-dimensionally (e.g., in matrix form) in a plane extending in a first direction X and a second direction Y.

[0036] The sensor array region (SAR) may include a light-receiving region (APS) and a light-shielding region (OB). The light-receiving region (APS) is arranged with active pixels that receive light and generate an active signal. The light-shielding region (OB) is arranged with optical black pixels that block light and generate an optical black signal. The light-shielding region (OB) may be formed, for example, along the periphery of the light-receiving region (APS), but this is only an example.

[0037] In some embodiments, dummy pixels (not shown) can be formed in the light-receiving region APS adjacent to the light-shielding region OB.

[0038] The junction region CR is formed around the sensor array region SAR. While the junction region CR is formed on one side of the sensor array region SAR, this is only illustrative. Wiring can be formed within the junction region CR and configured to transmit and receive electrical signals from the sensor array region SAR.

[0039] The pad region PR is formed around the sensor array region SAR. In some embodiments, the pad region PR is formed adjacent to the edge of the image sensor, but this is only illustrative. The pad region PR can be connected to an external device and configured to send and receive electrical signals between the image sensor and the external device in some embodiments.

[0040] In some embodiments, the sensor array region SAR may be a first region, and the linking region CR and pad region PR may be a second region. That is, the second region is located around the first region. However, the technical concept of the present invention is not limited thereto.

[0041] Figure 4 is a cross-sectional view taken along AA, BB, CC, and DD of Figure 3.

[0042] Referring to Figure 4, an image sensor according to several embodiments may include a first substrate 110, a pixel separation pattern 120, a dummy pixel separation pattern 320, a first wiring structure IS1, a second wiring structure IS2, a second substrate 210, a third wiring structure IS3, a surface insulating film 150, a first color filter 170, a grid pattern 160, a microlens 180, and a pad 131.

[0043] The first substrate 110 may be a semiconductor substrate. For example, the first substrate 110 may be bulk silicon or SOI (silicon-on-insulator). The first substrate 110 may be a silicon substrate, or it may contain other materials, such as silicon germanium, indium antimonide, lead tellurium compounds, indium arsenide, indium phosphide, gallium arsenide, or gallium antimonide. Alternatively, the first substrate 110 may have an epitaxial layer formed on a base substrate.

[0044] The first substrate 110 may include a first surface 110a and a second surface 110b that are opposite to each other. In embodiments described later, the first surface 110a is referred to as the front side of the first substrate 110, and the second surface 110b is referred to as the back side of the first substrate 110. In some embodiments, the second surface 110b of the first substrate 110 may be a light-receiving surface to which light is incident. That is, the image sensor according to some embodiments may be a back-illuminated (BSI) image sensor.

[0045] Multiple unit pixels are formed on the first substrate 110 of the sensor array region SAR. Although not shown in the drawing, multiple pixels are formed within the light-receiving region APS, arranged two-dimensionally (for example, in matrix form) in a plane including the first direction X and the second direction Y.

[0046] Each unit pixel may include a photoelectric conversion layer PD. The photoelectric conversion layer PD is formed within the first substrate 110 of the light-receiving region APS and the light-shielding region OB. The photoelectric conversion layer PD can generate charge in proportion to the amount of light incident from the outside. In some embodiments, a dummy photoelectric conversion layer is formed within a portion of the light-shielding region OB. That is, the photoelectric conversion layer PD formed in the light-shielding region OB may be an active photoelectric conversion layer or a dummy photoelectric conversion layer. However, the technical concept of the present invention is not limited thereto.

[0047] Although not shown in the figures, a dummy photoelectric conversion layer is also formed within the first substrate 110 of the connecting region CR. The dummy pixel separation pattern 320 of the connecting region CR can separate dummy pixels. Dummy pixels may include a dummy photoelectric conversion layer. However, the technical concept of the present invention is not limited thereto.

[0048] The photoelectric conversion layer (PD) may include, but is not limited to, at least one of the following: a photodiode, phototransistor, photogate, pinned photodiode, organic photodiode, quantum dot, or a combination thereof.

[0049] Each unit pixel may include a first electronic element TR1. In some embodiments, the first electronic element TR1 is formed on the first surface 110a of the first substrate 110. The first electronic element TR1 can be coupled with the photoelectric conversion layer PD to form a variety of transistors for processing electrical signals. For example, the first electronic element TR1 can form transistors such as the transfer transistor TG, reset transistor RG, source follower transistor SF, or selection transistor SEL described in the description relating to Figure 1b.

[0050] In some embodiments, the first electronic element TR1 may include a vertical transfer transistor. For example, a portion of the first electronic element TR1 constituting the transfer transistor TG described above may extend into the first substrate 110. Such a transfer transistor TG can reduce the area of ​​a unit pixel, thus enabling high integration of the image sensor.

[0051] The pixel separation pattern 120 is formed within the first substrate 110 of the sensor array region SAR. The dummy pixel separation pattern 320 is formed within the first substrate 110 of the connecting region CR. The pixel separation pattern 120 and the dummy pixel separation pattern 320 are formed, for example, by embedding insulating material in deep trenches formed by patterning the first substrate 110.

[0052] In some embodiments, the top surface 120US of the pixel separation pattern 120 and the top surface 320US of the dummy pixel separation pattern 320 can be located on the same plane. That is, the height from the first surface 110a of the first substrate 110 to the top surface 120US of the pixel separation pattern 120 is the same as the height from the first surface 110a of the first substrate 110 to the top surface 320US of the dummy pixel separation pattern 320. A detailed explanation of the pixel separation pattern 120 and the dummy pixel separation pattern 320 will be given later with reference to Figure 5.

[0053] The first wiring structure IS1 is formed on the first substrate 110. For example, the first wiring structure IS1 can cover the first surface 110a of the first substrate 110. The second wiring structure IS2 is formed on the first wiring structure IS1. The first wiring structure IS1 is positioned between the first substrate 110 and the second wiring structure IS2. That is, the upper surface of the first wiring structure IS1 can contact the first surface 110a of the first substrate 110. The lower surface of the first wiring structure IS1 can contact the upper surface of the second wiring structure IS2. The first substrate 110, the first wiring structure IS1, and the second wiring structure IS2 can constitute the first substrate structure 100.

[0054] The first wiring structure IS1 can consist of one or more wirings. For example, the first wiring structure IS1 may include a first inter-wiring insulating film 140, a plurality of wirings 141, 142 and a plurality of contacts 143, 145, 146, 147 within the first inter-wiring insulating film 140. In Figure 4, the number of wiring layers and their arrangement that constitute the first wiring structure IS1 are illustrative only. The first inter-wiring insulating film 140 may include, but is not limited to, at least one of silicon oxide, silicon nitride, silicon oxynitride, and a low-dielectric constant (low-k) material with a dielectric constant lower than that of silicon oxide.

[0055] In some embodiments, the first wiring structure IS1 may include a first wiring 141 in the sensor array region SAR and a second wiring 142 in the connecting region CR. The first wiring 141 may be electrically connected to a unit pixel in the sensor array region SAR. For example, the first wiring 141 may be connected to a first electronic element TR1. The second wiring 142 may extend from the sensor array region SAR. For example, the second wiring 142 may be electrically connected to at least a portion of the first wiring 141. Thus, the second wiring 142 may be electrically connected to a unit pixel in the sensor array region SAR.

[0056] In some embodiments, the first wiring structure IS1 may include a first contact 145 in the sensor array region SAR, a second contact 146, a third contact 147 in the connection region CR, and a fourth contact 143 in the pad region PR. The first contact 145 may be connected to the first electronic element TR1. The second contact 146 may be connected to the first substrate 110. The second contact 146 may be connected to the source / drain region. The third contact 147 may be connected to the second wiring 142 and the dummy pixel isolation pattern 320. The fourth contact 143 may be connected to the pad 131.

[0057] In some embodiments, a ground voltage or a negative voltage can be applied to the dummy pixel separation pattern 320 using the third contact 147. This effectively prevents ESD (electrostatic discharge) bruise defects in the image sensor according to some embodiments. Here, ESD bruise defect refers to a phenomenon in which irregularities such as bruises occur in the image generated by the accumulation of charge generated by ESD, etc., on the surface of the substrate (e.g., the first surface 110a).

[0058] The first wiring 141 and the second wiring 142 may, but are not limited to, include at least one of tungsten (W), copper (Cu), aluminum (Al), gold (Au), silver (Ag), and alloys thereof.

[0059] The first contact 145, the second contact 146, the third contact 147, and the fourth contact 143 may include, but are not limited to, at least one of tungsten (W), copper (Cu), aluminum (Al), gold (Au), silver (Ag), and alloys thereof.

[0060] The second wiring structure IS2 can consist of a second interwiring insulating film 130, pads 131 within the second interwiring insulating film 130, a first connection pattern 135, and a plurality of contacts 133. In Figure 4, the number of wiring layers and their arrangement that constitute the second wiring structure IS2 are illustrative only. The second interwiring insulating film 130 may, but is not limited to, include at least one of silicon oxide, silicon nitride, silicon oxynitride, and a low-dielectric constant (low-k) material with a dielectric constant lower than that of silicon oxide.

[0061] The pad 131 is formed on the first wiring structure IS1 within the second inter-wiring insulating film 130. The pad 131 is formed by being embedded within the second inter-wiring insulating film 130. The pad 131 may, but is not limited to, include at least one of tungsten (W), copper (Cu), aluminum (Al), gold (Au), silver (Ag), and alloys thereof.

[0062] The fifth contact 133 can connect the pad 131 to multiple wirings of the first wiring structure IS1. That is, the pad 131, the fifth contact 133, the second wiring 142, and the third contact 147 can be electrically connected. The fifth contact 133 may include, but is not limited to, at least one of tungsten (W), copper (Cu), aluminum (Al), gold (Au), silver (Ag), and alloys thereof.

[0063] The first connection pattern 135 is located on the underside of the pad 131. The first connection pattern 135 can be electrically connected to the pad 131. The first connection pattern 135 can be exposed from the surface of the second inter-wiring insulating film 130. The first connection pattern 135 can be exposed from the surface of the third inter-wiring insulating film 230.

[0064] In other words, the first connection pattern 135 may be exposed from the lower surface of the second inter-wiring insulating film 130. The first connection pattern 135 may be exposed from the upper surface of the third inter-wiring insulating film 230. The first connection pattern 135 may be electrically connected to the second connection pattern 235 inside the third inter-wiring insulating film 230. The first connection pattern 135 can have various columnar shapes, such as cylindrical, frustoconical, polygonal prism, and frustoconical prism.

[0065] The first connection pattern 135 may include a conductive material. The first connection pattern 135 may include, for example, copper (Cu), but is not limited to this.

[0066] The second substrate 210 may be bulk silicon or SOI (silicon-on-insulator). The second substrate 210 may be a silicon substrate, or it may contain other materials, such as silicon germanium, indium antimonide, lead tellurium compounds, indium arsenide, indium phosphide, gallium arsenide, or gallium antimonide. Alternatively, the second substrate 210 may have an epitaxial layer formed on a base substrate.

[0067] The second substrate 210 may include a third surface 210a and a fourth surface 210b that are opposite to each other. In some embodiments, the fourth surface 210b of the second substrate 210 may be the surface that faces the first surface 110a of the first substrate 110.

[0068] Multiple electronic elements are formed on the second substrate 210. For example, a second electronic element TR2 is formed on the fourth surface 210b of the second substrate 210. The second electronic element TR2 is electrically connected to the sensor array region SAR and can send and receive electrical signals with each unit pixel of the sensor array region SAR. For example, the second electronic element TR2 may include electronic elements that constitute the row decoder 20, row driver 30, column decoder 40, timing generator 50, correlated duplex sampler 60, analog-to-digital converter 70, or input / output buffer 80 in Figure 1a.

[0069] The third wiring structure IS3 is formed on the second substrate 210. For example, the second wiring structure IS2 can cover the fourth surface 210b of the second substrate 210. The second substrate 210 and the third wiring structure IS3 can constitute the second substrate structure 200.

[0070] The third wiring structure IS3 can be attached to the second wiring structure IS2. For example, the top surface of the third wiring structure IS3 can be attached to the bottom surface of the second wiring structure IS2.

[0071] The third wiring structure IS3 can consist of one or more wires, a plurality of contacts, and a second connection pattern 235. The third wiring structure IS3 may include a third inter-wire insulating film 230, a third wire 231, a sixth contact 233, and a second connection pattern 235.

[0072] In Figure 4, the number of wiring layers and their arrangement in the third wiring structure IS3 are illustrative only and not limited thereto. The third inter-wiring insulating film 230 may include, but is not limited to, at least one of silicon oxide, silicon nitride, silicon oxynitride, and low-dielectric-constant (low-k) materials with a dielectric constant lower than that of silicon oxide. In some embodiments, the third wiring structure IS3 may also include the same materials as the first wiring structure IS1 and the second wiring structure IS2.

[0073] The second connection pattern 235 is positioned on the underside of the first connection pattern 135. The second connection pattern 235 can be electrically connected to the first connection pattern 135. The second connection pattern 235 can be exposed from the surface of the second interwiring insulating film 130. The second connection pattern 235 can be exposed from the surface of the third interwiring insulating film 230.

[0074] In other words, the second connection pattern 235 may be exposed from the lower surface of the second inter-wiring insulating film 130. The second connection pattern 235 may be exposed from the upper surface of the third inter-wiring insulating film 230. The second connection pattern 235 may be electrically connected to the first connection pattern 135 within the second inter-wiring insulating film 130. The second connection pattern 235 can have various columnar shapes, such as cylindrical, frustoconical, polygonal prism, and frustoconical prism.

[0075] The second connection pattern 235 may include a conductive material. The second connection pattern 235 may include, for example, copper (Cu), but is not limited to this.

[0076] The third wiring 231 can be connected to the second connection pattern 235 via the sixth contact 233. The third wiring 231 can also be connected to the pad 131 using the second connection pattern 235 and the sixth contact 233.

[0077] The third wiring 231 may, but is not limited to, include at least one of tungsten (W), copper (Cu), aluminum (Al), gold (Au), silver (Ag), and alloys thereof.

[0078] Contact 6 233 may, but is not limited to, include at least one of tungsten (W), copper (Cu), aluminum (Al), gold (Au), silver (Ag), and alloys thereof.

[0079] The surface insulating film 150 is formed on the second surface 110b of the first substrate 110. The surface insulating film 150 can extend along the second surface 110b of the first substrate 110. In some embodiments, at least a portion of the surface insulating film 150 can be in contact with the pixel isolation pattern 120 and the dummy pixel isolation pattern 320.

[0080] The surface insulating film 150 may contain an insulating material. For example, the surface insulating film 150 may contain, but is not limited to, at least one of silicon oxide, silicon nitride, silicon oxynitride, aluminum oxide, hafnium oxide, and combinations thereof.

[0081] The surface insulating film 150 functions as an anti-reflective film, preventing the reflection of light incident on the first substrate 110 and thereby improving the light-receiving rate of the photoelectric conversion layer PD. Furthermore, the surface insulating film 150 functions as a planarization film, enabling the formation of the first color filter 170 and microlens 180, described later, at a uniform height.

[0082] The first color filter 170 is formed on the surface insulating film 150 of the light-receiving region APS. In some embodiments, the first color filters 170 are arranged to correspond to each unit pixel. For example, multiple first color filters 170 are arranged two-dimensionally (e.g., in matrix form) in a plane containing a first direction X and a second direction Y.

[0083] The first color filter 170 can have a variety of color filters depending on the unit pixel. For example, the first color filter 170 may be arranged in a Bayer pattern that includes a red color filter, a green color filter, and a blue color filter. However, this is only illustrative, and the first color filter 170 may also include a yellow filter, a magenta filter, and a cyan filter, and may further include a white filter.

[0084] The grid pattern 160 is formed on the surface insulating film 150. The grid pattern 160 is formed in a grid shape from a planar viewpoint and can be interposed between a plurality of first color filters 170.

[0085] The grid pattern 160 may include low refractive index materials with a refractive index lower than that of silicon (Si). For example, the grid pattern 160 may include, but is not limited to, at least one of silicon oxide, aluminum oxide, tantalum oxide, and combinations thereof. The grid pattern 160 containing low refractive index materials can improve the quality of the image sensor by refracting or reflecting light incident on the image sensor at an oblique angle.

[0086] In some embodiments, a first protective film 165 is formed on the surface insulating film 150 and the grid pattern 160. The first protective film 165 may be interposed between the surface insulating film 150 and the first color filter 170, and between the grid pattern 160 and the first color filter 170. For example, the first protective film 165 may extend along the top surface of the surface insulating film 150, and along the side and top profiles of the grid pattern 160.

[0087] The first protective film 165 may, for example, contain aluminum oxide, but is not limited thereto. The first protective film 165 can prevent damage to the surface insulating film 150 and the grid pattern 160.

[0088] The microlenses 180 are formed on the first color filter 170. The microlenses 180 are arranged to correspond to each unit pixel. For example, the microlenses 180 are arranged two-dimensionally (e.g., in matrix form) in a plane containing the first direction X and the second direction Y.

[0089] The microlens 180 has a convex shape and can have a predetermined radius of curvature. Therefore, the microlens 180 can focus the light incident on the photoelectric conversion layer PD. The microlens 180 may, but is not limited to, a light-transmitting resin.

[0090] In some embodiments, a second protective film 185 is formed on the microlens 180. The second protective film 185 can extend along the surface of the microlens 180. The second protective film 185 may include, for example, an inorganic oxide film. For example, the second protective film 185 may include, but is not limited to, at least one of silicon oxide, titanium oxide, zirconium oxide, hafnium oxide, and combinations thereof. In some embodiments, the second protective film 185 may include a low-temperature oxide (LTO).

[0091] The second protective film 185 can protect the microlenses 180 from external elements. For example, by including an inorganic oxide film, the second protective film 185 can protect microlenses 180 containing organic materials. Furthermore, the second protective film 185 can improve the light-gathering ability of the microlenses 180. For example, by filling the spaces between the microlenses 180, the second protective film 185 can reduce reflection, refraction, scattering, etc., of incident light reaching the spaces between the microlenses 180.

[0092] Some embodiments of the image sensor may further include a first connecting structure 350.

[0093] The first connecting structure 350 is formed within the light-shielding region OB. The first connecting structure 350 is formed within the connecting region CR. The first connecting structure 350 is positioned to overlap with the pixel separation pattern 120 in the third direction Z within the light-shielding region OB. The first connecting structure 350 is positioned to overlap with the dummy pixel separation pattern 320 in the connecting region CR in the third direction Z. The first connecting structure 350 can serve to block light incident on the light-shielding region OB or the connecting region CR.

[0094] The first connecting structure 350 is placed on the surface insulating film 150. The first connecting structure 350 does not need to be in contact with the pixel separation pattern 120 and the dummy pixel separation pattern 320.

[0095] The first connecting structure 350 may include, but is not limited to, at least one of a titanium (Ti) film, a titanium nitride (TiN) film, a tungsten (W) film, or a combination thereof.

[0096] In some embodiments, a second color filter 170C is placed on the second surface 110b of the first substrate 110 of the light-shielding region OB and the connecting region CR. The second color filter 170C can cover the first connecting structure 350. The second color filter 170C can be formed to cover a portion of the first protective film 165 within the light-shielding region OB and the connecting region CR. The second color filter 170C may, but is not limited to, a blue color filter.

[0097] In some embodiments, a third protective film 380 can be formed on the second color filter 170C. For example, the third protective film 380 is formed to cover a portion of the first protective film 165 in the light-shielding region OB and the connecting region CR. In some embodiments, the second protective film 185 can extend along the surface of the third protective film 380. The third protective film 380 may, but is not limited to, a light-transmitting resin. In some embodiments, the third protective film 380 may contain the same material as the microlens 180.

[0098] The pad 131 is embedded within the second inter-wiring insulating film 130. In some embodiments, the surface of the pad 131 may be exposed. The pad 131 may be exposed by penetrating the surface insulating film 150, the first substrate 110, the first inter-wiring insulating film 140, and the second inter-wiring insulating film 130. For example, an exposure opening ER is formed within the second inter-wiring insulating film 130 to expose the pad 131. Therefore, the pad 131 can be connected to an external device and configured to send and receive electrical signals between the image sensor and the external device according to some embodiments.

[0099] Figure 5 is an enlarged view of region P in Figure 4. Using Figure 5, we will explain the separation structure SST, namely the pixel separation pattern 120 and the dummy pixel separation pattern 320, in more detail.

[0100] Referring to Figures 4 and 5, the separation structures SST are arranged within the first substrate 110. Multiple separation structures SST can extend from the second surface 110b to the first surface 110a of the first substrate 110 in the third direction Z. Each separation structure SST can be separated in the first direction X.

[0101] The separation structure SST may include, for example, a pixel separation pattern 120 and a dummy pixel separation pattern 320. The pixel separation pattern 120 is formed within the sensor array region SAR of the first substrate 110. The dummy pixel separation pattern 320 is formed within the connecting region CR of the first substrate 110.

[0102] The separation structure SST may include a separation spacer film SSL, a separation filling film SFL, and a separation capping film SCL. The separation spacer film SSL and the surface insulating film 150 can define a separation recess SR. The separation filling film SFL can fill a portion of the separation recess SR. The separation capping film SCL can fill the remaining separation recess SR after the separation filling film SFL has filled it.

[0103] The separation spacer film SSL may include, for example, a pixel separation spacer film 121 and a dummy pixel separation spacer film 321. The separation filling film SFL may include a pixel separation filling film 125 and a dummy pixel separation filling film 325. The separation capping film SCL may include a pixel separation capping film 123 and a dummy pixel separation capping film 323. However, the technical concept of the present invention is not limited thereto.

[0104] A separation structure SST can define multiple unit pixels. A separation structure SST can have a grid shape from a planar perspective. A separation structure SST can separate multiple unit pixels.

[0105] The pixel separation pattern 120 is formed within the first substrate 110 of the sensor array region SAR. The pixel separation pattern 120 is formed, for example, by embedding an insulating material in deep trenches formed by patterning the first substrate 110.

[0106] The pixel separation pattern 120 can define multiple unit pixels. Although not shown in the drawing, the pixel separation pattern 120 is formed in a grid-like manner from a planar perspective, allowing multiple pixels to be separated from each other.

[0107] In some embodiments, the pixel separation pattern 120 can penetrate the first substrate 110. For example, the pixel separation pattern 120 can extend from the first surface 110a to the second surface 110b.

[0108] In some embodiments, the pixel isolation pattern 120 may include a pixel isolation spacer film 121, a pixel isolation filling film 125, and a pixel isolation capping film 123. The pixel isolation spacer film 121 is formed within the first substrate 110. The pixel isolation spacer film 121 and the surface insulating film 150 can define a pixel isolation recess 120R. The pixel isolation filling film 125 can fill a portion of the pixel isolation recess 120R. The pixel isolation capping film 123 can fill the remaining pixel isolation recess 120R after the pixel isolation filling film 125 has filled it.

[0109] In some embodiments, the pixel separation spacer film 121 may include an oxide film with a lower refractive index than the first substrate 110. For example, the pixel separation spacer film 121 may include, but is not limited to, at least one of silicon oxide, aluminum oxide, tantalum oxide, and combinations thereof.

[0110] The pixel separation spacer film 121, having a lower refractive index than the first substrate 110, can refract or reflect light incident obliquely on the photoelectric conversion layer PD. Furthermore, the pixel separation spacer film 121 can prevent photocharges generated in a specific unit pixel by incident light from moving to adjacent unit pixels due to random drift. In other words, the pixel separation spacer film 121 can improve the light-receiving efficiency of the photoelectric conversion layer PD, thereby improving the quality of image sensors in several embodiments.

[0111] In some embodiments, the pixel separation filling film 125 may contain a conductive material. For example, the pixel separation filling film 125 may contain polysilicon (poly Si), but is not limited thereto. In some embodiments, a ground voltage or a negative voltage may be applied to the pixel separation filling film 125 containing the conductive material. This effectively prevents ESD (electrostatic discharge) bruise defects in the image sensor according to some embodiments. Here, ESD bruise defect refers to a phenomenon in which bruise-like irregularities occur in the image generated by the accumulation of charge generated by ESD, etc., on the surface of the substrate (e.g., the first surface 110a).

[0112] In some embodiments, the pixel separation capping film 123 may include an insulating material. For example, the pixel separation capping film 123 may include, but is not limited to, an oxide-based insulating material.

[0113] The dummy pixel isolation pattern 320 is formed within the first substrate 110 of the connecting region CR. The dummy pixel isolation pattern 320 is formed, for example, by embedding insulating material in deep trenches formed by patterning the first substrate 110.

[0114] The dummy pixel separation pattern 320 can define multiple unit pixels. Although not shown in the drawing, the dummy pixel separation pattern 320 is formed in a grid shape from a planar perspective, allowing multiple pixels to be separated from each other.

[0115] In some embodiments, the dummy pixel isolation pattern 320 can penetrate the first substrate 110. For example, the dummy pixel isolation pattern 320 can extend from the first surface 110a to the second surface 110b.

[0116] In some embodiments, the dummy pixel isolation pattern 320 may include a dummy pixel isolation spacer film 321, a dummy pixel isolation filling film 325, and a dummy pixel isolation capping film 323. For example, a dummy pixel isolation spacer film 321 is formed in the first substrate 110. The dummy pixel isolation spacer film 321 and the surface insulating film 150 can define a dummy pixel isolation recess 320R. The dummy pixel isolation filling film 325 can fill a portion of the dummy pixel isolation recess 320R. The dummy pixel isolation capping film 323 can fill the remaining dummy pixel isolation recess 120R after the dummy pixel isolation filling film 325 has filled it.

[0117] The description of the substances contained in the dummy pixel separation spacer film 321, the dummy pixel separation filling film 325, and the dummy pixel separation capping film 323 is the same as the description of the substances contained in the pixel separation spacer film 121, the pixel separation filling film 125, and the pixel separation capping film 123.

[0118] In some embodiments, the vertical depth of the pixel separation capping film 123 is greater than the vertical depth of the dummy pixel separation capping film 323. That is, the height H1 from the first surface 110a of the first substrate 110 to the bottom surface 125BS of the pixel separation filling film 125 is greater than the height H2 from the first surface 110a of the first substrate 110 to the bottom surface 325BS of the dummy pixel separation filling film 325.

[0119] As the depth of the dummy pixel separation capping film 323 decreases, the first contact 145, the second contact 146, and the third contact 147 are formed at the same level. "At the same level" means that they are formed by the same manufacturing process.

[0120] In some embodiments, the upper surface 120US of the pixel separation pattern 120 can be coplanar with the upper surface 320US of the dummy pixel separation pattern 320. That is, the height from the first surface 110a of the first substrate 110 to the upper surface 120US of the pixel separation pattern 120 can be the same as the height from the first surface 110a of the first substrate 110 to the upper surface 320US of the dummy pixel separation pattern 320.

[0121] Since the third contact 147 is connected to the lower surface of the dummy pixel separation filling film 325, a separate connecting structure does not need to be formed on the upper surface 320US of the dummy pixel separation pattern 320.

[0122] Figure 6 is an illustrative diagram illustrating an image sensor according to several embodiments. For the sake of explanation, the focus will be on the differences from what was explained using Figures 4 and 5.

[0123] Referring to Figure 6, the first connecting structure 350 can be directly connected to the dummy pixel separation pattern 320.

[0124] The first connecting structure 350 is formed in the connecting region CR and the light-shielding region OB on the pixel separation pattern 120, the dummy pixel separation pattern 320, and the surface insulating film 150. The first connecting structure 350 is electrically connected to the dummy pixel separation pattern 320, and a ground voltage or negative voltage can be applied to the dummy pixel separation pattern 320. Therefore, charges generated by ESD, etc., can be discharged to the first connecting structure 350 via the dummy pixel separation pattern 320, effectively preventing ESD defects.

[0125] The top surface 120US of the pixel separation pattern 120 can be positioned higher than the top surface of the dummy pixel separation pattern 320. That is, the height from the first surface 110a of the first substrate 110 to the top surface 120US of the pixel separation pattern 120 may be greater than the height from the first surface 110a of the first substrate 110 to the top surface 320US of the dummy pixel separation pattern 320.

[0126] Figure 7 is an illustrative diagram illustrating an image sensor according to several embodiments. For the sake of explanation, the focus will be on the differences from what was explained using Figures 4 and 5.

[0127] Referring to Figure 7, some embodiments of the image sensor may further include a second connecting structure 450.

[0128] The second connecting structure 450 is formed within the connecting region CR. The second connecting structure 450 is placed on the surface insulating film 150 of the connecting region CR. The second connecting structure 450 can electrically connect the first substrate structure 100 and the second substrate structure 200.

[0129] For example, a first trench 450t is formed that penetrates the first substrate 110 and the first interwiring insulating film 140 of the connecting region CR. The first trench 450t can expose the fourth wiring 144. A second connecting structure 450 can be formed within the first trench 450t and connected to the fourth wiring 144. In some embodiments, the second connecting structure 450 can extend along the side and bottom profiles of the first trench 450t.

[0130] In some embodiments, the second connecting structure 450 may be connected to the pad 131 via the fourth wiring 144, the fourth contact 143, and the fifth contact 133. Alternatively, the second connecting structure 450 may be connected to the dummy pixel isolation pattern 320 via the fourth wiring 144 and the third contact 147. That is, the dummy pixel isolation pattern 320, the second connecting structure 450, and the pad 131 may be electrically connected.

[0131] The second connecting structure 450 may include, but is not limited to, at least one of a titanium (Ti) film, a titanium nitride (TiN) film, a tungsten (W) film, or a combination thereof.

[0132] In some embodiments, the first protective film 165 can cover the second connecting structure 450. For example, the first protective film 165 can extend along the profile of the second connecting structure 450.

[0133] In some embodiments, a first filling insulating film 460 is formed on the second connecting structure 450 to fill the first trench 450t. The first filling insulating film 460 may, but is not limited to, at least one of silicon oxide, aluminum oxide, tantalum oxide, and combinations thereof.

[0134] Figure 8 is an illustrative diagram illustrating an image sensor according to several embodiments. For ease of explanation, the focus will be on the differences from those explained using Figures 4, 5, and 7.

[0135] Referring to Figure 8, the pad 131 is not embedded and positioned within the interwiring insulating film. Image sensors according to some embodiments may further include a third connecting structure 550. Image sensors according to some embodiments may not include a second wiring structure IS2.

[0136] The third connecting structure 550 is formed within the pad region PR. The third connecting structure 550 is placed on the surface insulating film 150 of the pad region PR. The third connecting structure 550 can electrically connect the second substrate structure 200 to external devices, etc.

[0137] For example, a second trench 550t is formed within the first substrate structure 100 and the second substrate structure 200 of the pad region PR, exposing the fifth wiring 236. The third connecting structure 550 is formed within the second trench 550t and can contact the fifth wiring 236.

[0138] Furthermore, a pad trench 131t is formed within the first substrate 110 of the pad region PR. The third connecting structure 550 may be formed within the pad trench 131t and exposed. In some embodiments, the third connecting structure 550 may extend along the profiles of the side and bottom surfaces of the second trench 550t and the pad trench 131t.

[0139] In some embodiments, a second filling insulating film 560 is formed on the third connecting structure 550 to fill the second trench 550t. The second filling insulating film 560 may, but is not limited to, include at least one of silicon oxide, aluminum oxide, tantalum oxide, and combinations thereof.

[0140] The pad 131 is placed on the third connecting structure 550. The pad 131 can fill the third connecting structure 550 and the remaining pad trench 131t.

[0141] The second connecting structure 450 can be connected to the sixth wiring 234 in the second wiring structure IS2. The fifth wiring 236 and the sixth wiring 234 can be connected to each other. Thus, the pad 131, the third connecting structure 550, the second connecting structure 450, and the dummy pixel isolation pattern can be electrically connected.

[0142] In some embodiments, a seventh wiring 232 is formed within the third wiring-inter-insulating film 230 of the sensor array region SAR. The seventh wiring 232 can be connected to the fifth wiring 236 and the sixth wiring 234.

[0143] Figure 9 is an illustrative diagram illustrating an image sensor according to several embodiments. For the sake of explanation, the focus will be on the differences from what was explained using Figures 4 and 5.

[0144] Referring to Figure 9, the first connection pattern 135 is located within the third inter-wiring insulating film 230.

[0145] That is, the first connection pattern 135 may be included in the third wiring structure IS3. The first connection pattern 135 is located on the lower surface of the pad 131. The lower surface of the pad 131 can be coplanar with the lower surface of the second inter-wiring insulating film 130. The second connection pattern 235 is located within the third inter-wiring insulating film 230. The second connection pattern 235 is embedded within the third inter-wiring insulating film 230. That is, the second connection pattern 235 does not have to be exposed from the surface of the second inter-wiring insulating film 130. The second connection pattern 235 does not have to be exposed from the surface of the third inter-wiring insulating film 230.

[0146] The first connection pattern 135 may be, for example, a solder bump, but is not limited to this. The first connection pattern 135 can have a variety of shapes, such as a land, ball, pin, or pillar.

[0147] The first connection pattern 135 may include solder material. For example, each of the first connection patterns 135 may include, but is not limited to, at least one of lead (Pb), tin (Sn), indium (In), bismuth (Bi), antimony (Sb), silver (Ag), and alloys thereof.

[0148] Figure 10 is an illustrative diagram illustrating an image sensor according to several embodiments. For ease of explanation, the focus will be on the differences from those described using Figures 4 and 5.

[0149] Referring to Figure 10, some embodiments of the image sensor may further include an element isolation film STI embedded within the first substrate 110.

[0150] The element isolation film STI is formed by penetrating the first surface 110a of the first substrate 110. The element isolation film STI may include, but is not limited to, at least one of, a silicon oxide film, a silicon nitride film, and a silicon oxynitride film.

[0151] The separation structure SST is formed by penetrating the element separation film STI. That is, the pixel separation pattern 120 and the dummy pixel separation pattern 320 are formed by penetrating the element separation film STI. It has been shown that the bottom surface 125BS of the pixel separation filling film 125 and the bottom surface 325BS of the dummy pixel separation filling film 325 are coplanar with the bottom surface of the element separation film STI, but this is for the sake of explanation and is not limited thereto.

[0152] Figures 11a to 11d are enlarged views of the R region in Figure 3. The dummy pixel separation pattern 320 and the third contact 147 will be explained in more detail with reference to Figures 11a to 11d. For ease of explanation, the focus will be on the differences from the explanation using Figures 1 to 10.

[0153] Referring to Figures 11a to 11d, the dummy pixel separation pattern 320 is arranged in a grid configuration.

[0154] In a plane extending in the first direction X and the second direction Y, the dummy pixel separation pattern 320 can separate each unit pixel PX.

[0155] The dummy pixel separation pattern 320 may include a first line region L1 extending in a first direction X. The dummy pixel separation pattern 320 may include a second line region L2 extending in a second direction Y. The dummy pixel separation pattern 320 may include an intersection region IR where the first line region L1 and the second line region L2 intersect.

[0156] In Figure 11a, the third contact 147 is located in the intersection region IR where the first line region L1 and the second line region L2 intersect. That is, the third contact 147 does not overlap with the unit pixel PX in the first direction X and the second direction Y.

[0157] In Figure 11b, the third contact 147 is located on the first line region L1. The third contact 147 is not located on the second line region L2. The third contact 147 may have an island shape; that is, the third contact 147 overlaps with the unit pixel PX in the second direction Y, but does not overlap with the unit pixel PX in the first direction X. The width of the third contact 147 in the first direction X is smaller than the width of the unit pixel PX in the first direction X.

[0158] In Figure 11c, the third contact 147 extends along the first line region L1. That is, a portion of the third contact 147 is located on the second line region L2.

[0159] In Figure 11d, the third contact 147 is located on the first line region L1. The third contact 147 is not located on the second line region L2. The width of the third contact 147 in the first direction X is the same as the width of a unit pixel PX in the first direction X.

[0160] Figure 12 shows a conceptual layout of an image sensor according to several embodiments. For the sake of explanation, we will focus on the differences from what was explained using Figure 2.

[0161] Referring to Figure 12, some embodiments of the image sensor may further include a third substrate structure 300. The first substrate structure 100, the second substrate structure 200, and the third substrate structure 300 may be stacked sequentially along the third direction Z. The third substrate structure 300 is positioned below the second substrate structure 200. That is, the second substrate structure 200 is positioned between the first substrate structure 100 and the third substrate structure 300.

[0162] The third substrate structure 300 may include a memory device. For example, the third substrate structure 300 may include a volatile memory device such as a DRAM or SRAM. The third substrate structure 300 can receive signals from the first substrate structure 100 and the second substrate structure 200 and process the signals via the memory device. In other words, an image sensor including the third substrate structure 300 corresponds to a 3-stack image sensor.

[0163] Figures 13 to 22 are intermediate drawings illustrating several embodiments of image sensor manufacturing methods.

[0164] Figures 13 to 22 illustrate several embodiments of methods for manufacturing an image sensor.

[0165] Referring to Figure 13, an element isolation film STI is formed within the first substrate 110. The first substrate 110 may include a first surface 110a and a second surface 110b opposite to the first surface 110a.

[0166] A photoelectric conversion layer PD is formed within the first substrate 110 of the light-shielding region OB. A photoelectric conversion layer PD is not formed within the first substrate 110 of the connecting region CR. However, the technical concept of the present invention is not limited thereto. The separation of the light-shielding region OB and the connecting region CR is shown here for the sake of explanation and is not limiting.

[0167] A mask film 700 and a sacrificial film 800 are formed on the first surface 110a of the first substrate 110. The mask film 700 may contain, for example, silicon nitride. The sacrificial film 800 may contain, but is not limited to, silicon oxide.

[0168] A separation filling trench SFL_t is formed that penetrates the sacrificial film 800, the mask film 700, and the element isolation film STI. The separation filling trench SFL_t is formed within the first substrate 110. That is, the bottom surface of the separation filling trench SFL_t may be higher than the second surface 110b of the first substrate 110.

[0169] A pre-separation spacer film SSL_P is formed along the side walls of the separation filling trench SFL_t, the bottom surface of the separation filling trench SFL_t, and the top surface of the sacrificial film 800. The pre-separation spacer film SSL_P may, but is not limited to, include at least one of, for example, silicon oxide, aluminum oxide, tantalum oxide, and combinations thereof.

[0170] Referring to Figure 14, a pre-separation filling membrane SFL_P is formed to fill the separation filling trench SFL_t.

[0171] The pre-separation filling film SFL_P can cover the pre-separation spacer film SSL_P. The pre-separation filling film SFL_P may contain conductive material. For example, the pre-separation filling film SFL_P may contain, but is not limited to, polysilicon (poly Si).

[0172] Referring to Figure 15, the first photosensitive film PR1 is formed on the pre-separation filling film SFL_P.

[0173] The first photosensitive film PR1 is formed on the pre-separation filling film SFL_P of the connecting region CR. The first photosensitive film PR1 is formed in a position that overlaps perpendicularly with the separation filling trench SFL_t of the connecting region CR.

[0174] Referring to Figure 16, a portion of the pre-separation filling film SFL_P can be removed. Next, the first photosensitive film PR1 can be removed.

[0175] The first photosensitive film PR1 can create a step in the pre-separation filling film SFL_P. That is, the pre-separation filling film SFL_P in the area where the first photosensitive film PR1 is formed may protrude more than the pre-separation filling film SFL_P in the area where the first photosensitive film PR1 is not formed.

[0176] Referring to Figure 17, the pre-separation filling membrane SFL_P is removed and the separation filling membrane SFL is formed.

[0177] The separation filling film SFL may include a pixel separation filling film 125 formed in the light-shielding region OB and a dummy pixel separation filling film 325 formed in the connecting region CR. The depth of the pixel separation filling film 125 may be less than the depth of the dummy pixel separation filling film 325. The height H1 from the first surface 110a of the first substrate 110 to the bottom surface 125BS of the pixel separation filling film 125 may be greater than the height H2 from the first surface 110a of the first substrate 110 to the bottom surface 325BS of the dummy pixel separation filling film 325.

[0178] Referring to Figure 18, a pre-separation capping membrane SCL_P is formed on the separation filling membrane SFL.

[0179] The pre-separation capping film SCL_P can cover the upper surface of the pre-separation spacer film SSL_P. The pre-separation capping film SCL_P may, but is not limited to, contain silicon oxide.

[0180] Referring to Figure 19, the pre-separation spacer film SSL_P and the pre-separation capping film SCL_P are removed, and the separation spacer film SSL and the separation capping film SCL are formed.

[0181] In other words, a separation structure SST is formed. The separation structure SST may include a separation spacer membrane SSL, a separation filling membrane SFL, and a separation capping membrane SCL.

[0182] The separation structure SST includes a pixel separation pattern 120 formed in the light-shielding region OB and a dummy pixel separation pattern 320 formed in the connecting region CR.

[0183] The separation spacer film SSL includes a pixel separation spacer film 121 formed in the light-shielding region OB and a dummy pixel separation spacer film 321 formed in the connecting region CR.

[0184] The separation capping film SCL includes a pixel separation capping film 123 formed in the light-shielding region OB and a dummy pixel separation capping film 323 formed in the connecting region CR.

[0185] The pre-separation spacer film SSL_P and the pre-separation capping film SCL_P are removed, and the first surface 110a of the first substrate 110 can be exposed.

[0186] Referring to Figure 20, the first inter-wiring insulating film 140 is formed on the first surface 110a of the first substrate 110.

[0187] A first electronic element TR1 is formed within the first inter-wiring insulating film. A second photosensitive film PR2 is formed on the first inter-wiring insulating film 140.

[0188] The second photosensitive film PR2 can be used as a mask for forming the first to third contacts, which will be described later.

[0189] Referring to Figure 21, the first contact trench 145t, the second contact trench 146t, and the third contact trench 147t can be formed by using the second photosensitive film PR2 as a mask.

[0190] The first contact trench 145t can penetrate the first inter-wiring insulating film 140 and expose the first electronic element TR1. The second contact trench 146t can penetrate the first inter-wiring insulating film 140 and expose the first surface 110a of the first substrate 110. The third contact trench 147t can penetrate the first inter-wiring insulating film 140 and the dummy pixel separation capping film 323 and expose the dummy pixel separation filling film 325.

[0191] The first contact trench 145t, the second contact trench 146t, and the third contact trench 147t are formed at the same level.

[0192] Referring to Figure 22, the first contact 145, the second contact 146, and the third contact 147 are formed.

[0193] The first contact 145 can fill the first contact trench 145t. The second contact 146 can fill the second contact trench 146t. The third contact 147 can fill the third contact trench 147t.

[0194] The first contact 145 can be connected to the first electronic element TR1. The second contact 146 can be connected to the first substrate 110. The third contact 147 can be connected to the dummy pixel isolation filling film 325.

[0195] The first contact 145, the second contact 146, and the third contact 147 are formed at the same level.

[0196] Although not shown, referring again to Figure 4, after the first contact 145, the second contact 146, and the third contact 147 are formed, the second inter-wiring insulating film 130 is formed on the first inter-wiring insulating film 140. A pad 131 and multiple wirings and multiple contacts can be formed within the second inter-wiring insulating film.

[0197] Next, the second surface 110b of the first substrate 110 can be removed using a planarization process. The first substrate 110 can be removed until the separation filling film SFL is exposed. That is, the first substrate 110 can be removed until the bottom surface of the separation spacer film SSL is removed. Therefore, the second surface 110b of the first substrate 110 can expose the separation filling film SFL.

[0198] Although embodiments of the present invention have been described above with reference to the attached drawings, the present invention is not limited to the embodiments described above and can be manufactured in a variety of different forms. A person with ordinary skill in the art to which the present invention belongs will understand that the invention can be implemented in other specific forms without changing the technical idea or essential features of the present invention. Therefore, it should be understood that the above-described embodiment is illustrative in all respects and not limiting. [Explanation of Symbols]

[0199] 110 First board 210 Second board 120-pixel separation pattern 320 dummy pixel separation pattern SST separation structure 125-pixel separation filling film 325 Dummy Pixel Separation Filling Film 131 pads 147 Third Contact 170 First Color Filter 180 Microlens PD (Photoelectric Conversion Layer)

Claims

1. A substrate including a first surface and a second surface that are opposite to each other, and including a first region and a second region disposed around the first region, Within the first region of the substrate, there are a plurality of unit pixels including a photoelectric conversion layer, In a first region of the substrate, a pixel separation pattern extending from the first surface of the substrate to the second surface of the substrate, separating each of the unit pixels, comprising a pixel separation spacer film and a pixel separation filling film, wherein the pixel separation filling film is a pixel separation pattern that fills a portion of the pixel separation recess defined by the pixel separation spacer film. In the second region of the substrate, a dummy pixel isolation pattern extending from the first surface of the substrate to the second surface of the substrate, including a dummy pixel isolation spacer film and a dummy pixel isolation filling film, wherein the dummy pixel isolation filling film is a dummy pixel isolation pattern that fills a portion of the dummy pixel isolation recess defined by the dummy pixel isolation spacer film, On the first surface of the substrate, a wiring structure including an interwiring insulating film and a first wiring within the interwiring insulating film is provided. A color filter is placed on the second surface of the substrate, It includes a first contact that is directly connected to the dummy pixel isolation filling film and connects the dummy pixel isolation filling film to the first wiring, The separation structure comprising the pixel separation pattern and the dummy pixel separation pattern has a grid shape, the pixel separation spacer film and the dummy pixel separation spacer film are made of an insulating film, the pixel separation filling film and the dummy pixel separation filling film contain a conductive material, a ground voltage or a negative voltage is applied to the dummy pixel separation filling film and the pixel separation filling film using the first contact, and the dummy pixel separation filling film and the pixel separation filling film are exposed from the second surface of the substrate. An image sensor in which the height from the first surface of the substrate to the bottom surface of the pixel separation filling film is greater than the height from the first surface of the substrate to the bottom surface of the dummy pixel separation filling film.

2. The image sensor according to claim 1, wherein the upper surface of the pixel separation pattern is located on the same plane as the upper surface of the dummy pixel separation pattern.

3. The aforementioned pixel separation pattern includes a pixel separation capping film on the pixel separation filling film. The dummy pixel separation pattern includes a dummy pixel separation capping film on the dummy pixel separation filling film. The image sensor according to claim 1 or 2, wherein the vertical depth of the dummy pixel separation capping film is less than the vertical depth of the pixel separation capping film.

4. The present invention further includes a pad disposed on the wiring structure and connected to the first wiring, The image sensor according to claim 1 or 2, wherein the first contact is connected to the pad.

5. A first connection pattern connected to the lower surface of the pad, The image sensor according to claim 4, further comprising a second connection pattern connected to the first connection pattern on the lower surface of the first connection pattern.

6. A substrate including a first surface and a second surface that are opposite to each other, and including a first region and a second region disposed around the first region, A separation structure extending from the first surface of the substrate to the second surface of the substrate, comprising a separation spacer film and a separation filling film, and having a grid shape, wherein the separation filling film is a separation structure that fills a portion of the separation recess defined by the separation spacer film, Within the first region of the substrate, there are a plurality of unit pixels including a photoelectric conversion layer, wherein the photoelectric conversion layer comprises a plurality of unit pixels arranged within the substrate separated by the separation structure, On the first surface of the substrate, a wiring structure including an interwiring insulating film and wiring within the interwiring insulating film is provided, In the first region of the substrate, a microlens is disposed on the second surface of the substrate, A pad placed on the aforementioned wiring structure and connected to the aforementioned wiring, The second region of the substrate includes a contact that is directly connected to the separation filling film and connects the separation filling film to the wiring, The separation spacer film is made of an insulating film, the separation filling film contains a conductive material, a ground voltage or a negative voltage is applied to the separation filling film using the contact, and the separation filling film is exposed from the second surface of the substrate. An image sensor in which, in a first region of the substrate, the height from the first surface of the substrate to the bottom surface of the separation filling film is greater than the height from the first surface of the substrate to the bottom surface of the separation filling film in a second region of the substrate.

7. In the second region of the substrate, the separation structure includes a first line region extending in a first direction and a second line region extending in a second direction perpendicular to the first direction. The image sensor according to claim 6, wherein the contact is located at the point where the first line region and the second line region intersect.

8. In the second region of the substrate, the separation structure includes a first line region extending in a first direction and a second line region extending in a second direction perpendicular to the first direction. The image sensor according to claim 6, wherein the contact extends along the first line region.

9. In the second region of the substrate, the separation structure includes a first line region extending in a first direction and a second line region extending in a second direction perpendicular to the first direction. The image sensor according to claim 6, wherein the contact is not located at the point where the first line region and the second line region intersect.

10. A substrate including a first surface and a second surface that are opposite to each other, and including a first region and a second region disposed around the first region, Within the first region of the substrate, there are a plurality of unit pixels including a photoelectric conversion layer, In a first region of the substrate, a pixel separation pattern extending from the first surface of the substrate to the second surface of the substrate, separating each of the unit pixels, comprising a pixel separation spacer film and a pixel separation filling film, wherein the pixel separation filling film is a pixel separation pattern that fills a portion of the pixel separation recess defined by the pixel separation spacer film. In the second region of the substrate, a dummy pixel isolation pattern extending from the first surface of the substrate to the second surface of the substrate, including a dummy pixel isolation spacer film and a dummy pixel isolation filling film, wherein the dummy pixel isolation filling film is a dummy pixel isolation pattern that fills a portion of the dummy pixel isolation recess defined by the dummy pixel isolation spacer film, On the first surface of the substrate, a wiring structure including an interwiring insulating film and wiring within the interwiring insulating film is provided, A color filter is placed on the second surface of the substrate, A pad placed on the aforementioned wiring structure and connected to the aforementioned wiring, A first connection pattern connected to the lower surface of the pad, On the lower surface of the first connection pattern, a second connection pattern connected to the first connection pattern, It includes a contact that is directly connected to the dummy pixel isolation filling film and connects the dummy pixel isolation filling film to the wiring, The separation structure comprising the pixel separation pattern and the dummy pixel separation pattern has a grid shape, the pixel separation spacer film and the dummy pixel separation spacer film are made of an insulating film, the pixel separation filling film and the dummy pixel separation filling film contain a conductive material, a ground voltage or a negative voltage is applied to the dummy pixel separation filling film and the pixel separation filling film using the contact, and the dummy pixel separation filling film and the pixel separation filling film are exposed from the second surface of the substrate. An image sensor in which the height from the first surface of the substrate to the bottom surface of the pixel separation filling film is greater than the height from the first surface of the substrate to the bottom surface of the dummy pixel separation filling film.

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