Image sensor

Abstract

An image sensor includes: a substrate including a first photodiode (PD) region and a second PD region adjacent to the first PD region; the first PD is provided with a first area, and the first PD is located in the first PD area; a second PD, the second PD being located in the second PD region, the second PD having a second area smaller than the first area; the micro lens is positioned on the substrate and covers the first PD region; and a light splitter located between the substrate and the microlens, the light splitter including a material having a refractive index different from a refractive index of the microlens. The optical splitter extends from the first PD region to the second PD region.

Description

Technical Field

[0001] The present disclosure relates to image sensors, and more particularly, to image sensors having a split photodiode (PD) structure. Background Art

[0002] An image sensor, which is a semiconductor-based sensor, generates an electrical signal when light is received, and may include a pixel array having a plurality of pixels and a circuit for driving the pixel array and generating an image. Each pixel may include a PD that generates a charge in response to external light and a pixel circuit that converts the charge generated by the PD into an electrical signal. In addition to cameras for capturing images or videos, image sensors can also be widely used in smart phones, tablet personal computers (PCs), laptop computers, televisions, cars, and the like. Recently, in order to improve the dynamic range of image sensors, research has been conducted to improve the performance of image sensors with a divided PD structure. Summary of the invention

[0003] Embodiments of the inventive concept provide an image sensor that improves image quality.

[0004] In addition, problems to be solved by the present inventive concept are not limited to the above-mentioned problems, and other problems to be solved by those skilled in the art can be clearly understood from the following description.

[0005] An embodiment of the inventive concept provides an image sensor, the image sensor comprising: a substrate including a first photodiode (PD) region and a second PD region adjacent to the first PD region; a first PD having a first area, the first PD being located in the first PD region; a second PD having a second area smaller than the first area, the second PD being located in the second PD region; a microlens located on the substrate and covering the first PD region; and a beam splitter located between the substrate and the microlens, the beam splitter comprising a material having a refractive index different from that of the microlens. The beam splitter extends from the first PD region to the second PD region.

[0006] Embodiments of the inventive concept also provide an image sensor, the image sensor comprising: a substrate in which a first photodiode (PD) region and a second PD region are defined; a first PD having a first area in the substrate, the first PD being located in the first PD region; a second PD having a second area smaller than the first area in the substrate, and the second PD being located in the second PD region; a color filter located on the substrate; and a beam splitter located between the substrate and the color filter, or on the color filter. The beam splitter includes a material having a refractive index different from that of the color filter, and the beam splitter vertically overlaps at least a portion of the first PD region and at least a portion of the second PD region.

[0007] Embodiments of the inventive concept also provide an image sensor, the image sensor comprising: a substrate, the substrate comprising a first photodiode (PD) region and a second PD region adjacent to the first PD region; a first PD, the first PD is located in the first PD region and has a first area; a second PD, the second PD is located in the second PD region and has a second area smaller than the first area; a deep trench isolation (DTI), the deep trench isolation separates the first PD region from the second PD region and passes through the substrate; a microlens, the microlens is located on the substrate and covers the first PD region; a color filter, the color filter is located between the substrate and the microlens; a beam splitter, the beam splitter is located between the substrate and the color filter, or between the color filter and the microlens; and an interconnection layer, the interconnection layer is located below the substrate, and the interconnection layer includes an insulating film and a conductive interconnection located in the insulating film. The beam splitter vertically overlaps at least a portion of the first PD region and at least a portion of the second PD region, and the beam splitter has a refractive index different from that of the microlens and the color filter. BRIEF DESCRIPTION OF THE DRAWINGS

[0008] Embodiments will be more clearly understood from the following detailed description taken in conjunction with the accompanying drawings, in which:

[0009] Figure 1 is a schematic block diagram of an image processing apparatus including an image sensor according to some example embodiments;

[0010] Figure 2 and Figure 3 is a perspective view schematically illustrating an image processing apparatus including an image sensor according to some example embodiments;

[0011] Figure 4is a circuit diagram illustrating a pixel circuit included in an image sensor according to some example embodiments;

[0012] Figure 5 is a top view of an image sensor according to some example embodiments;

[0013] Figure 6 is a diagram of an image sensor according to some example embodiments, and is Figure 5 A cross-sectional view taken along line AA';

[0014] Figure 7 is a top view of an image sensor according to some example embodiments;

[0015] Figure 8 is a top view of an image sensor according to some example embodiments;

[0016] Fig. 9 is a top view of an image sensor according to some example embodiments;

[0017] Fig.10 is a top view of an image sensor according to some example embodiments;

[0018] Fig.11 is a top view of an image sensor according to some example embodiments;

[0019] Fig.12 is a top view of an image sensor according to some example embodiments;

[0020] Fig.13 is a top view of an image sensor according to some example embodiments;

[0021] Fig.14 is a top view of an image sensor according to some example embodiments;

[0022] Fig.15 is a view of an image sensor according to some example embodiments, and is Fig.14 A cross-sectional view taken along line BB';

[0023] Fig.16 is a diagram of an image sensor according to some example embodiments, and is Figure 5 A cross-sectional view taken along line AA'.

[0024] Fig.17 is a diagram of an image sensor according to some example embodiments, and is Figure 5 A cross-sectional view taken along line AA'.

[0025] Fig.18 is a top view of an image sensor according to some example embodiments;

[0026] Fig.19 is a diagram of an image sensor according to some example embodiments, and is Fig.18 A cross-sectional view taken along line CC';

[0027] Fig. 20 is a top view of an image sensor according to some example embodiments;

[0028] Fig.21 is a diagram of an image sensor according to some example embodiments, and is Fig. 20 A cross-sectional view taken along line D-D';

[0029] Fig. 22 is a top view of an image sensor according to some example embodiments;

[0030] Fig.23 is a top view of an image sensor according to some example embodiments;

[0031] Fig.24 is a top view of an image sensor according to some example embodiments;

[0032] Fig.25 is a top view of an image sensor according to some example embodiments;

[0033] Fig.26 is a view of an image sensor according to some example embodiments, and is Fig.25 A cross-sectional view taken along line EE';

[0034] Fig. 27 is a top view of an image sensor according to some example embodiments;

[0035] Fig.28 is a view of an image sensor according to some example implementations, and is Fig. 27 A cross-sectional view taken along line F-F';

[0036] Fig.29 is a top view of an image sensor according to some example embodiments;

[0037] Fig.30 is a view of an image sensor according to some example embodiments, and is Fig.29 A cross-sectional view taken along line G-G'. DETAILED DESCRIPTION

[0038] Hereinafter, example embodiments are described in detail with reference to the accompanying drawings. The same reference numerals are used for the same components in the drawings, and redundant descriptions thereof are omitted.

[0039] When the term "about" or "substantially" is used in conjunction with a numerical value in this specification, the associated numerical value is intended to include manufacturing or operating tolerances (e.g., ±10%) around the numerical value. In addition, when the words "substantially" and "substantially" are used in conjunction with a geometric shape, it is not intended to require the accuracy of the geometric shape, but the latitude of the shape is within the scope of the present disclosure. In addition, regardless of whether a numerical value or shape is modified as "about" or "substantially", it will be understood that these values ​​and shapes should be interpreted as including manufacturing or operating tolerances (e.g., ±10%) around the numerical value or shape. When a range is specified, the range includes all values ​​therebetween, such as in increments of 0.1%.

[0040] Additionally, for example, “at least one of A, B, and C” and similar language (e.g., “at least one selected from the group consisting of A, B, and C”) may be interpreted as A only, B only, C only, or any combination of two or more of A, B, and C, such as, for example, ABC, AB, BC, and AC.

[0041] Figure 1 is a schematic block diagram of an image processing apparatus 1 including an image sensor 10 according to some example embodiments.

[0042] Reference Figure 1 , an image processing apparatus 1 of some example embodiments may include an image sensor 10 and an image processor 20. The image sensor 10 may include a pixel array 11, a row driver 12, a column driver 13, a readout circuit 14, a timing controller 15, and the like.

[0043] The image sensor 10 may operate according to a control command received from the image processor 20, convert light reflected from an object to be imaged into an electrical signal, and output the electrical signal to the image processor 20. The pixel array 11 included in the image sensor 10 may include a plurality of pixels PX, and each pixel PX may include a photodiode (PD) that generates charges when receiving light. In some example embodiments, each pixel PX may include two or more PDs.

[0044] In addition, each pixel PX may include a pixel circuit for generating an electrical signal from the charge generated in the PD. For example, the pixel circuit may include a pixel TR such as a transfer transistor (TR), a drive TR, a selection TR, and a reset TR. When one pixel PX has two or more PDs, each pixel PX may include a pixel circuit for processing the charge generated in each of the two or more PDs. That is, when one pixel PX has two or more PDs, the pixel circuit may include at least one of a transfer TR, a drive TR, a selection TR, and a reset TR.

[0045] In the image processing apparatus 1 of some example embodiments, one pixel PX may include two PDs. Accordingly, the pixel PX may have a split PD structure. In addition, in the image processing apparatus 1 of some example embodiments, one pixel PX may include a first pixel circuit that processes charges generated by one PD and a second pixel circuit that processes charges generated by another PD. The first pixel circuit and the second pixel circuit may each include a plurality of semiconductor devices. The first pixel circuit may generate a first pixel signal from charges generated by one PD and output the first pixel signal, and the second pixel circuit may generate a second pixel signal from charges generated by another PD and output the second pixel signal. The first pixel signal and the second pixel signal may each include a reset voltage and a pixel voltage.

[0046] The row driver 12 may drive the pixel array 11 in row units. For example, the row driver 12 may generate a transfer control signal for controlling a transmission TR of each pixel PX, a reset control signal for controlling a reset TR of each pixel PX, and a selection control signal for controlling a selection TR of each pixel PX.

[0047] The column driver 13 may include a correlated double sampler (CDS), an analog-to-digital converter (ADC), etc. The CDS may perform correlated double sampling to acquire pixel signals through column lines connected to pixels PX included in a row selected by a row selection signal supplied from the row driver 12. The ADC may convert an output from the CDS into a digital signal and transmit the digital signal to the readout circuit 14.

[0048] The readout circuit 14 may include a latch or buffer circuit and an amplifier circuit for temporarily storing digital signals. In addition, the readout circuit 14 may process the digital signal received from the column driver 13 to generate image data. The operation timing of the row driver 12, the column driver 13 and the readout circuit 14 may be determined by the timing controller 15. The timing controller 15 may operate according to a control command transmitted from the image processor 20. The image processor 20 may process the image data output from the readout circuit 14 and output the image data to a display device, etc., or store the image data in a storage device such as a memory. In addition, when the image processing device 1 of some example embodiments is installed in an autonomous vehicle, the image processor 20 may perform signal processing on the image data and send the image data to a main controller that controls the autonomous vehicle.

[0049] Figure 2 and Figure 3 is a perspective view schematically showing an image processing apparatus including an image sensor according to an embodiment.

[0050] Reference Figure 2, the image processing device 2 of some example embodiments may include a plurality of stacked chips. For example, the image processing device 2 may include: an upper chip 40 including a sensing area SA, a middle chip 50 including a logic circuit area LC, and a lower chip 60 having a storage area MC and a dummy area DC. In some example embodiments, the upper chip 40 may be stacked on the middle chip 50 at a wafer level, and the lower chip 60 may be connected to a lower portion of the middle chip 50 at a chip level.

[0051] The upper chip 40 may include a sensing area SA in which a plurality of pixels PX are arranged, and a first pad area PA1 surrounding the sensing area SA. A plurality of upper pads PAD may be arranged in the first pad area PA1. The upper pads PAD may be connected to pads arranged in the second pad area PA2 of the middle chip 50 through vias, etc., to be connected to the logic circuit of the logic circuit area LC.

[0052] Each pixel PX may include: a PD that generates charges when receiving light, and a pixel circuit that converts the charges generated in the PD into an electrical signal. The PD may include an organic PD, a semiconductor PD, etc. In some example embodiments, each pixel PX may include a plurality of semiconductor PDs. The pixel circuit may include a plurality of pixels TR for converting the charges generated in the PD into an electrical signal.

[0053] The middle chip 50 may include: a logic circuit region LC in which a logic circuit is arranged, and a second pad region PA2 surrounding the logic circuit region LC. The logic circuit of the logic circuit region LC may include a circuit for driving a pixel circuit located in the upper chip 40, for example, a row driver, a column driver, and a timing controller. The logic circuit of the logic circuit region LC may be connected to the pixel circuit through the pads and paths of the first pad region PA1 and the second pad region PA2.

[0054] The lower chip 60 may include a storage area MC and a dummy area DC. In some example embodiments, the dummy area DC may be omitted. In addition, in some embodiments, the lower chip 60 may have a package structure. For example, since each of the storage area MC and the dummy area DC is manufactured into a chip and sealed together with a sealing material, the lower chip 60 may have a package structure including two chips. Memory devices such as dynamic random access memory (DRAM) devices or static random access memory (SRAM) devices may be arranged in the storage area MC. However, the memory devices arranged in the storage area MC are not limited to DRAM devices or SRAM devices. The memory devices may not be arranged in the dummy area DC. The dummy area DC may have the function of supporting the upper chip 40 and the middle chip 50, rather than the function of storing data. The memory devices of the storage area MC may be electrically connected to at least some logic circuits of the logic circuit area LC of the middle chip 50 through bumps or through electrodes.

[0055] Reference Figure 3 , the image processing device 3 of some example embodiments may include an upper chip 70 and a lower chip 80. The upper chip 70 may include: a sensing area SA provided with a plurality of pixels PX, a logic circuit area LC provided with devices for driving the plurality of pixels PX, and a pad area PA surrounding the sensing area SA and the logic circuit area LC. A plurality of upper pads PAD may be arranged in the pad area PA, and the upper pads PAD may be connected to a storage device of a storage area MC provided in the lower chip 80 through a via or the like. The lower chip 80 may include a storage area MC and a dummy area DC. The lower chip 80 may be connected to Figure 2 The lower chip 60 of the image processing device 2 is substantially the same as that of the lower chip 60 of the image processing device 2. Accordingly, a detailed description of the lower chip 80 is omitted.

[0056] Figure 4 is a circuit diagram illustrating a pixel circuit included in the image sensor 100 according to some example embodiments.

[0057] Reference Figure 4 The pixel circuit of the image sensor 100 of the present embodiment may include a first PD (LPD), a second PD (SPD), a first transmission TR (TX1), a second transmission TR (TX2), a first floating diffusion (FD) (FD1), a second FD (FD2), a first switch SW1, a second switch SW2, a reset TR (RX), a drive TR (DX), a selection TR (SX), a metal capacitor Mcap, a capacitor EXC, and a dual conversion gain TR (DCG).

[0058] The first PD (LPD) and the second PD (SPD) may be photodiodes including an n-type impurity region and a p-type impurity region. According to the pixel circuit of the image sensor 100, electric signals may be output using charges generated by the first PD (LPD) and the second PD (SPD). The first PD (LPD) may have a size, for example, several to several dozen times that of the second PD (SPD). Here, the size may refer to a horizontal area. For example, the horizontal area of ​​the first PD (LPD) may refer to the area of ​​the first PD (LPD) along the substrate 101 (for example, see Figure 6 ), or in other words, the area of ​​the first PD (LPD) when viewed in a top view. Figure 5 and Figure 6 It can be seen that the light receiving area of ​​the first PD (LPD) can be several times to dozens of times the light receiving area of ​​the second PD (SPD).

[0059] The first PD (LPD) may be connected to the first FD (FD1) through a first transmission TR (TX1). The first transmission TR (TX1) may transfer charges accumulated in the first PD (LPD) to the first FD (FD1) based on a transmission control signal transmitted from a row driver. The first PD (LPD) may generate electrons as primary charge carriers.

[0060] The second PD (SPD) may be connected to the second FD (FD2) through the second transmission TR (TX2). The second transmission TR (TX2) may transfer the charge accumulated in the second PD (SPD) to the second FD (FD2) based on the transmission control signal transmitted from the row driver. The second PD (SPD) may also generate electrons as the main charge carriers. For example, when the second transmission TR (TX2) is turned on, the charge generated in the second PD (SPD) may move to the second FD (FD2). When the second transmission TR (TX2) is in the off state, the second PD (SPD) may generate charge in response to light, and whenever the second transmission TR (TX2) is turned on, the charge generated in the second PD (SPD) may move from the second PD (SPD) to the second FD (FD2) to be accumulated therein.

[0061] In some example embodiments, the first switch SW1 and the second FD (FD2) may be used to adjust the conversion gain (CG) of the charge generated in the first PD (LPD) or the capacitance of the pixel. The first switch SW1 may be implemented as a TR. For example, the first FD (FD1) may be combined with the second FD (FD2) by turning on the first switch SW1, thereby increasing the capacity of the pixel to increase the dynamic range (DR) and change the CG. That is, the image sensor 100 of some example embodiments may have a dual CG structure.

[0062] In addition, the charge generated in the second PD (SPD) may be stored in the metal capacitor Mcap. The second switch SW2 may be located between the metal capacitor Mcap and the second FD FD2. The second switch SW2 may also be implemented as a TR like the first switch SW1. Accordingly, the metal capacitor Mcap may store charge in response to the second transmission TR (TX2) and the operation of the second switch SW2. According to some example embodiments, the second switch SW2 may not be provided. According to some example embodiments, in the absence of the second switch SW2, the metal capacitor Mcap may store charge in response to the operation of the second transmission TR (TX2).

[0063] In addition, the first switch SW1 and the second switch SW2 may be located between the metal capacitor Mcap and the first FD FD1. Accordingly, the charge of the metal capacitor Mcap may be moved to the first FD FD1 by the on / off operation of the first switch SW1 and the second switch SW2. As described above, the second PD (SPD) has a relatively small light receiving area compared to the first PD (LPD), and saturation of the second PD (SPD) may be limited or prevented by moving the charge of the second PD (SPD) to be stored in the metal capacitor Mcap.

[0064] In the image sensor 100 of some example embodiments, the second PD (SPD) may be used for the purpose of improving the dynamic range (DR) of the image sensor 100. That is, by using the metal capacitor Mcap, charges may be stored and output without saturating the image sensor 100 even under high illumination.

[0065] The driving TR (DX) can operate as a source follower buffer amplifier by the charge accumulated in the first FD (FD1). The driving TR (DX) can amplify the charge accumulated in the first FD (FD1) and transmit the signal to the selecting TR (SX). For example, the first FD (FD1) can be connected to the gate of the driving TR (DX), and the power supply voltage (VDD) can be connected to the source of the reset TR (RX) and the driving TR (DX). The column line can be connected to the drain of the selecting TR (SX) so that the voltage Vout can be output. The selecting TR (SX) operates according to the selection control signal input from the row driver, and switching and addressing operations can be performed. When the selection control signal from the row driver is applied to the gate of the selecting TR (SX), the voltage Vout can be output through the column line connected to the selecting TR (SX). The voltage Vout can be detected by the column driver and the readout circuit connected to the column line.

[0066] The column driver and the readout circuit may detect the reset voltage in a state where charges are not accumulated in the first FD (FD1), and may detect the pixel voltage in a state where charges are accumulated in the first FD (FD1). For example, the image sensor 100 of some example embodiments may be configured to detect the reset voltage in a state where charges are accumulated in the first FD (FD1). Figure 1 The CDS included in the column driver 13 shown in FIG. 1 calculates the difference between the reset voltage and the pixel voltage to generate image data.

[0067] The dual conversion gain TR (DCG) may be coupled to the capacitor EXC. Depending on the on or off state of the dual conversion gain TR (DCG), the first FD (FD1) may or may not be connected to the capacitor EXC. Thus, the capacitance of the first FD (FD1) may be adjusted. When the dual conversion gain TR (DCG) is turned off, the capacitance of the first FD (FD1) may be reduced to increase CG, thereby improving the performance of the image sensor 100 under low light conditions. When the dual conversion gain TR (DCG) is turned on, the capacitance of the first FD (FD1) may be increased to increase the charge storage capacity (or full well capacity), thereby improving the performance of the image sensor 100 under high light conditions. In this way, the dual conversion gain TR (DCG) may perform the function of improving the image quality of the image sensor 100 by dynamically adjusting the on / off in low light conditions and high light conditions.

[0068] The first PD (LPD) may share a column line with the second PD (SPD). Accordingly, when a first pixel voltage corresponding to the charge of the first PD (LPD) is output through the column line, the second PD (SPD) may be separated from the column line. For example, when the first pixel voltage is output to the column line, the second PD (SPD) may be separated from the column line by turning off at least one of the second transmission TR (TX2) and the first switch SW1. In order to generate a first pixel voltage using the charge of the first PD (LPD) and output the first pixel voltage to the column line, the charge generated in the first PD (LPD) when the first transmission TR (TX1) is turned on may be accumulated in the first FD (FD1).

[0069] Similarly, when the second pixel voltage corresponding to the charge of the second PD (SPD) is output to the column line, the first PD (LPD) can be separated from the column line. For example, when the second pixel voltage is output to the column line, the first transmission TR (TX1) can be turned off to separate the first PD (LPD) from the column line. In order to generate the second pixel voltage using the charge of the second PD (SPD) and output the second pixel voltage to the column line, the second transmission TR (TX2) and the first switch SW1 can be turned on to connect the first FD (FD1) to the second FD (FD2). The charge of the second PD (SPD) can be accumulated in the first FD (FD1) and the second FD (FD2), and converted into a voltage by the driving TR (DX).

[0070] Figure 5 is a top view of an image sensor 100 according to some example embodiments. Figure 6 is a diagram of an image sensor 100 according to some example embodiments, and is Figure 5 A cross-sectional view taken along line AA'.

[0071] Reference Figure 5 and Figure 6 , the image sensor 100 may include a substrate 101 , a first PD (LPD), a second PD (SPD), a deep trench isolation (DTI) 130 , a metal grid 172 , a color filter 170 , a beam splitter LS, a microlens 180 , and an interconnection layer 200 .

[0072] The substrate 101 may include silicon. However, the material of the substrate 101 is not limited to silicon. For example, the substrate 101 may include a single element semiconductor such as germanium (Ge) or a compound semiconductor such as silicon carbide (SiC), gallium arsenide (GaAs), indium arsenide (InAs), or indium phosphide (InP).

[0073] The plurality of unit pixels PXu may be arranged in a two-dimensional array structure in a first direction X and a second direction Y. In this specification, the first direction X is a direction parallel to the upper surface of the substrate 101 , and the second direction Y is a direction parallel to the upper surface of the substrate 101 and perpendicular to the first direction X.

[0074] Each unit pixel PXu may include one first PD region AR1 and one second PD region AR2 corresponding to the one first PD region AR1. For example, the unit pixel PXu may include one first PD region AR1 and one second PD region AR2 arranged on the upper left portion of the one first PD region AR1 (for example, at a position near a corner region of the one first PD region AR1). The unit pixels PXu may be separated from each other by the DTI 130 structure. The first PD region AR1 and the second PD region AR2 may be separated from each other by the DTI 130 structure.

[0075] For example, the unit pixels PXu may be separated from each other by the front-end DTI structure.

[0076] In a top view, the first PD region AR1 may have an octagonal shape, and the second PD region AR2 may have a quadrilateral shape. In addition, the second PD region AR2 may be located between four first PD regions AR1 adjacent to the second PD region AR2. For example, one second PD region AR2 may be surrounded by four first PD regions AR1. In addition, the four second PD regions AR2 may be alternately arranged to be adjacent to four of the eight sides of the first PD region AR1.

[0077] In some example embodiments, the first PD region AR1 may have an octagonal shape and the second PD region AR2 may have a quadrilateral shape, as described. However, in some other example embodiments, the shapes of the first PD region AR1 and the second PD region AR2 constituting each unit pixel PXu are not limited to the above shapes. For example, the first PD region AR1 may have a quadrilateral or hexagonal shape. In addition, the second PD region AR2 may have a quadrilateral shape. For example, the second PD region AR2 may also be disposed inside the first PD region AR1. In this case, the second PD region AR2 may have various shapes such as a circle, an ellipse, or a polygon instead of a quadrilateral. The shape may vary depending on the design of the image sensor 100 to be implemented.

[0078] The first PD (LPD) may be disposed in a first PD region AR1 within the substrate 101, and the second PD (SPD) may be disposed in a second PD region AR2 within the substrate 101. In addition, the first PD region AR1 may be separated from the second PD region AR2 by the DTI 130.

[0079] The DTI 130 may pass through the substrate 101 in a vertical direction. Since the DTI 130 is formed in a structure passing through the substrate 101, crosstalk between pixels due to oblique incident light may be limited or prevented. In addition, each of the first PD (LPD) and the second PD (SPD) may be formed substantially adjacent to the DTI 130, and accordingly, a light receiving area may be expanded to improve a fill factor.

[0080] The DTI 130 may include a conductive layer 132 and an insulating film 134. The conductive layer 132 may include, for example, polysilicon or polysilicon doped with impurities. However, the material of the conductive layer 132 is not limited to the above materials. For example, the conductive layer 132 may include a metal, a metal silicide, or a conductive material containing a metal. The insulating film 134 may surround the outside of the conductive layer 132 and insulate the conductive layer 132 from the substrate 101. The insulating film 134 may include, for example, an oxide or nitride such as silicon oxide, silicon nitride, and silicon oxynitride. However, the material of the insulating film 134 is not limited to the above materials.

[0081] The color filter 170 may be disposed on the upper surface of the substrate 101. The color filter 170 may cover the upper surface of the substrate 101. The color filter 170 may include any one of a red color filter, a blue color filter, and a green color filter. In some example embodiments, the color filter 170 may be omitted. When the color filter 170 is omitted, other transparent structures that allow light to be transmitted therethrough may be included where the color filter 170 may exist. When the color filter 170 is omitted, the image sensor 100 may be used as an infrared sensor.

[0082] The metal grid 172 may be located between the substrate 101 and the color filter 170. The metal grid 172 may vertically overlap the DTI 130. The vertical thickness of the metal grid 172 may be less than the vertical thickness of the color filter 170. However, the inventive concept is not limited thereto, and the vertical thickness of the metal grid 172 may be the same as the vertical thickness of the color filter 170. The vertical thickness refers to a thickness in a direction perpendicular to the upper surface of the substrate 101.

[0083] The metal grid 172 can separate the color filters 170 from each other. The metal grid 172, together with the DTI 130, can limit or prevent the light incident on the color filter 170 from being transmitted to the PD of the adjacent unit pixel PXu. Accordingly, the occurrence of crosstalk between the unit pixels PXu of the image sensor 100 can be reduced. The metal grid 172 may include a conductive material such as a metal and / or a metal nitride. For example, the metal grid 172 may include tungsten (W), titanium (Ti) and / or titanium nitride (TiN). However, the material of the metal grid 172 is not limited to W, Ti and TiN. A grid structure including a low refractive index material may be additionally formed on the metal grid 172.

[0084] The beam splitter LS may be disposed on the color filter 170. The beam splitter LS may have a quadrilateral shape in a top view. The beam splitter LS may have a long axis extending in a direction from the center of the first PD area AR1 to the center of the second PD area AR2 in a top view. The beam splitter LS may extend from the first PD (LPD) to the second PD (SPD) without disconnection. The beam splitter LS may vertically overlap at least a portion of the first PD (LPD), and may vertically overlap at least a portion of the second PD (SPD).

[0085] The beam splitter LS may include a material having a refractive index different from that of the color filter 170 and the microlens 180. For example, the beam splitter LS may include TiO 2 、SiO 2 , SiN and at least one of amorphous silicon.

[0086] On the color filter 170 , the microlens 180 may vertically overlap the first PD area AR1 . The microlens 180 may vertically overlap the entire first PD area AR1 and may vertically overlap a portion of the second PD area AR2 . Another portion of the second PD area AR2 may not vertically overlap the microlens 180 .

[0087] On the first PD area AR1, the microlens 180 may cover the color filter 170 and the beam splitter LS. On the second PD area AR2, the microlens 180 may cover at least a portion of the color filter 170 and at least a portion of the beam splitter LS. Accordingly, a portion of the upper surface of the color filter 170 and a portion of the upper surface of the beam splitter LS may be exposed to the outside from the microlens 180. Alternatively, the microlens 180 may cover the entirety of the beam splitter LS on the second PD area AR2. This may vary depending on the design of the image sensor 100 to be implemented. The microlens 180 may have a dome shape or a hemispherical shape.

[0088] In some example embodiments, on the second PD area AR2, the microlens 180 may completely cover the color filter 170 and the beam splitter LS, or may not cover at least a portion of each of the color filter 170 and the beam splitter LS. The horizontal area of ​​the microlens 180 may vary. This may vary according to the design of the image sensor 100 to be implemented.

[0089] The microlens 180 may be transparent so that light can be transmitted through the microlens 180. The microlens 180 may include an organic material such as a polymer. For example, the microlens 180 may include a photoresist material or a thermosetting resin.

[0090] External light may pass through the microlens 180. The light transmitted through the microlens 180 may travel to the first PD (LPD) through the color filter 170, or may be incident on the beam splitter LS. A portion of the light traveling to the beam splitter LS may be repeatedly reflected by the interface between the beam splitter LS and the microlens 180 and the interface between the beam splitter LS and the color filter 170. In this way, a portion of the light traveling to the beam splitter LS may travel from the first PD (LPD) to the second PD (SPD). The light traveling to the second PD (SPD) may leave the beam splitter LS and may be incident on the second PD (SPD). That is, the beam splitter LS, as the name implies, may perform the function of distributing the light incident on the first PD area AR1 to the second PD area AR2.

[0091] In the absence of the beam splitter LS, if a microlens 180 covering the first PD area AR1 and a microlens 180 covering the second PD area AR2 are separately provided, the two microlenses 180 inevitably have different heights. This is because the microlens 180 may have a dome shape or a hemispherical shape. In this case, when the angle of light incident on the two microlenses 180 increases based on the direction perpendicular to the upper surface of the substrate 101, the degree of vignetting occurring in the first PD area AR1 and the second PD area AR2 may vary, and therefore, the relative illumination in the first PD (LPD) and the second PD (SPD) may vary. In addition, considering that the first PD (LPD) and the second PD (SPD) constitute a unit pixel PXu in the image sensor 100, the optical centers may not match each other due to the positional difference of the first PD (LPD) and the second PD (SPD). In addition, the mismatch of the optical centers may cause color separation between the first PD (LPD) and the second PD (SPD). In addition, if the heights of the two microlenses 180 are different, as the incident light angle increases, the microlenses of the first PD (LPD) cover the microlenses of the second PD (SPD), so that the optical characteristics of the first PD (LPD) and the second PD (SPD) may vary.

[0092] The image sensor 100 according to the present inventive concept may include: a substrate 101 including a first PD (LPD) and a second PD (SPD), a beam splitter LS located on the substrate 101, and a microlens 180 located on the beam splitter LS. The beam splitter LS may include a material having a refractive index different from that of the microlens 180. As a result, light incident on the first PD (LPD) is incident on the beam splitter LS through the microlens 180, and is incident on the second PD (SPD) through the beam splitter LS. Therefore, since only one microlens 180 can be located in the unit pixel PXu, problems that may be caused by different heights of the microlens 180 can be limited, reduced, or prevented. For the above reasons, the image quality of the image sensor 100 can be improved.

[0093] The pixel circuit may be arranged below the substrate 101. The remaining pixel circuits not shown may be arranged below the substrate 101. Figure 6 For example, referring only to the pixel circuit shown, the first transmission TR ( Figure 4 The gate TG1 and the first FD (FD1) of the second transmission TR ( Figure 4 The gate TG2 of the transistor TX2 and the second FD (FD2) may be located in a lower portion in the second PD region AR2 of the substrate 101.

[0094] The first transmission TR Figure 4 The gate TG1 of TX1) and the second transmission TR ( Figure 4 The gate TG2 of the first transmission TR( Figure 4 The gate TG1 of the second transmission TR ( TX1 ) may extend to vertically pass through the lower portion of the substrate 101 to be connected to the first PD (LPD). Figure 4 The gate TG2 of the first transmission TR ( TX2 ) may extend to vertically pass through the lower portion of the substrate 101 to be connected to the second PD (SPD). Figure 4 The gate TG1 of TX1) and the second transmission TR ( Figure 4 The gate TG2 of TX2 in FIG. 1 may include a conductive material such as doped silicon.

[0095] Although not shown, reset TR ( Figure 4 The gate of RX) and the driver TR ( Figure 4 The gate of DX) and the selection TR ( Figure 4 The gate of the SX in the embodiment may have a horizontal structure. Accordingly, the gate of the horizontal structure may be located on the lower surface of the substrate 101.

[0096] In addition, a plurality of heavily-doped regions 140 may be arranged on the lower surface of the substrate 101. The heavily-doped region 140 may include a first FD (FD1), a second FD (FD2), and a source / drain region of the pixel TR. Figure 4 The heavily doped region 140 on the gate TG1 side of the first transmission TR ( TX1 in FIG. 1 ) may constitute the first FD ( FD1 ). Similarly, the second transmission TR ( Figure 4 The heavily doped region 140 on the gate TG2 side of the driving TR ( TX2 in FIG. 1 ) may constitute a second FD ( FD2 ). Although not shown, the driving TR ( Figure 4 The gate of DX) and the selection TR ( Figure 4 The heavily doped regions 140 on both sides of the gate of SX in the embodiment of the present invention can constitute the driving TR ( Figure 4 DX in) and select TR( Figure 4 SX) in the source / drain region.

[0097] The interconnection layer 200 may be disposed on the lower surface of the substrate 101. The interconnection layer 200 may include an insulating film 202 and a conductive interconnection 204 located within the insulating film 202. The conductive interconnection 204 may be connected to the first transmission TR ( Figure 4 The gate TG1 of TX1) and the second transmission TR ( Figure 4 The conductive interconnect 204 may also be connected to the gate TG2 of TX2 in FIG. Figure 6 Other pixel circuits not shown.

[0098] Figures 7 to 13 1 is a top view of image sensors 100a to 100g according to some example embodiments. Figure 5 and Figure 6 The descriptions that are identical are given, and only the differences are described in detail.

[0099] Reference Figures 7 to 13 , the planar shape of the light splitter LS can be modified variously. Figure 7, the horizontal area of ​​the beam splitter LS1 of the image sensor 100a in the second PD area AR2 may be larger than its horizontal area in the edge of the first PD area AR1. The edge of the first PD area AR1 may be a portion (e.g., an edge portion) surrounding the center (e.g., a central portion) of the first PD area AR1. For example, the beam splitter LS1 may cover the entire second PD area AR2. When the horizontal area of ​​the beam splitter LS1 in the second PD area AR2 is larger than its horizontal area in the edge of the first PD area AR1, the ratio of light traveling to the second PD area AR2 to light incident on the second PD (SPD) may increase. Accordingly, the efficiency of light transmission to the second PD (SPD) may be increased, thereby improving the sensitivity of the second PD (SPD).

[0100] Reference Figure 8 and Fig. 9 , the horizontal area of ​​the beam splitters LS2 and LS3 of the image sensors 100b and 100c in the second PD area AR2 may be larger than the horizontal area thereof at the edge of the first PD area AR1. The edge of the first PD area AR1 may be a portion surrounding the center of the first PD area AR1. For example, the beam splitters LS2 and LS3 may cover the entire second PD area AR2.

[0101] In addition, the horizontal area of ​​the beam splitters LS2 and LS3 at the center of the first PD area AR1 may be larger than the horizontal area thereof at the edge of the first PD area AR1. For example, the beam splitters LS2 and LS3 may have a quadrilateral planar shape at the center of the first PD area AR1. Here, the directions of the corners of the quadrilateral may be modified in various ways. Figure 8 As shown in , the horizontal sides of the quadrilateral may be parallel to the first direction X or the second direction Y. Alternatively, as Fig. 9 As shown in , the horizontal sides of the quadrilateral can be parallel to the substrate ( Figure 6 101) and may be parallel to a direction intersecting the first direction X and the second direction Y. For example, Fig. 9 However, the inventive concept is not limited thereto, and at the center of the first PD area AR1 , the beam splitters LS2 and LS3 may have various planar shapes such as a circle, an ellipse, and a polygon.

[0102] In this case, the amount of light incident on the beam splitters LS2 and LS3 can be increased, so that the ratio of light incident on the first PD area AR1 to light traveling to the second PD area AR2 can be increased. Accordingly, the sensitivity of the second PD (SPD) can be improved.

[0103] Reference Fig.10, the image sensor 100d may include a beam splitter LS4. The horizontal area of ​​the beam splitter LS4 at the center of the first PD region AR1 may be greater than the horizontal area thereof at the edge of the first PD region AR1. The edge of the first PD region AR1 may be a portion surrounding the center of the first PD region AR1. Figure 5 As described, the beam splitter LS4 may overlap vertically with a portion of the second PD area AR2. The beam splitter LS4 may not cover at least a portion of the second PD area AR2. For example, the beam splitter LS4 may have a quadrilateral planar shape at the center of the first PD area AR1. However, the inventive concept is not limited thereto, and the beam splitter LS4 may have various planar shapes such as a circle, an ellipse, and a polygon at the center of the first PD area AR1.

[0104] Reference Fig.11 and Fig.12 , the thickness TT of the beam splitters LS5 and LS6 of the image sensors 100e and 100f may vary in a direction from the center of the first PD area AR1 to the center of the second PD area AR2.

[0105] Reference Fig.11 , the thickness TT of the beam splitter LS5 of the image sensor 100e may gradually increase in the direction from the center of the first PD region AR1 to the center of the second PD region AR2. The thickness TT of the beam splitter LS5 refers to the thickness of the beam splitter LS5 in the direction of the substrate ( Figure 6 The thickness of the optical splitter LS5 in a direction parallel to the upper surface of the optical splitter LS5 (101) and perpendicular to the direction from the center of the first PD region AR1 to the center of the second PD region AR2. As an example, the thickness TT of the optical splitter LS5 may increase continuously in the direction from the center of the first PD region AR1 to the center of the second PD region AR2. Fig.11 , the sidewall of the beam splitter LS5 is shown as a straight line, but the inventive concept is not limited thereto. The sidewall of the beam splitter LS5 may have a curved shape.

[0106] Reference Fig.12 , the thickness TT of the beam splitter LS6 of the image sensor 100f may gradually decrease in the direction from the center of the first PD region AR1 to the center of the second PD region AR2. The thickness TT of the beam splitter LS6 refers to the thickness of the beam splitter LS6 in the direction of the substrate ( Figure 6 The thickness of the beam splitter LS6 in a direction parallel to the upper surface of 101 in the figure and perpendicular to the direction from the center of the first PD region AR1 to the center of the second PD region AR2. As an example, the thickness TT of the beam splitter LS6 may be continuously reduced in the direction from the center of the first PD region AR1 to the center of the second PD region AR2. Fig.12 , the sidewall of the beam splitter LS6 is shown as a straight line, but the inventive concept is not limited thereto. The sidewall of the beam splitter LS6 may have a curved shape.

[0107] Reference Fig.13 , the beam splitter LS7 of the image sensor 100g may cover the entire second PD region AR2. The thickness TT of the beam splitter LS7 may be constant from the center of the first PD region AR1 to the center of the second PD region AR2. The thickness TT of the beam splitter LS7 refers to the thickness of the beam splitter LS7 at the position adjacent to the substrate ( Figure 6 The thickness in a direction parallel to the upper surface of 101 in the figure and perpendicular to the direction from the center of the first PD region AR1 to the center of the second PD region AR2.

[0108] Fig.14 is a top view of an image sensor 100h according to some example embodiments. Fig.15 is a view of an image sensor 100h according to some example embodiments, and is Fig.14 A cross-sectional view taken along line BB'. Figure 5 and Figure 6 The descriptions that are identical are given, and only the differences are described in detail.

[0109] Reference Fig.14 and Fig.15 , at least a portion of the metal grid 172 at the interface between the first PD region AR1 and the second PD region AR2 of the image sensor 100h may be omitted. The metal grid 172 may be omitted in a portion vertically overlapping with the beam splitter LS. In other words, in a top view, the metal grid 172 may be separated from the beam splitter LS. In this case, even if the metal grid 172 is high, light may smoothly travel to the second PD region AR2 through the beam splitter LS. Accordingly, the sensitivity of the second PD (SPD) may be improved.

[0110] Fig.16 is a diagram of an image sensor 100i according to some example embodiments, and is Figure 5 A cross-sectional view taken along line AA'. Fig.17 is a diagram of an image sensor 100j according to some example embodiments, and is Figure 5 A cross-sectional view taken along line AA'. Figure 5 and Figure 6 The descriptions that are identical are given, and only the differences are described in detail.

[0111] Reference Fig.16, the beam splitter LS of the image sensor 100i may be located between the substrate 101 and the color filter 170. The beam splitter LS may directly cover the upper surface of the substrate 101. The beam splitter LS may cover at least a portion of the metal grid 172 at the boundary between the first PD area AR1 and the second PD area AR2. The microlens 180 may be separated from the beam splitter LS. The color filter 170 may cover the upper surface and the side surface of the beam splitter LS. In this case, in order to allow light to pass smoothly through the beam splitter LS, at least a portion of the metal grid 172 located at the boundary between the first PD area AR1 and the second PD area AR2 may be omitted.

[0112] Reference Fig.17 , the image sensor 100j may include a first metal grid 173 and a second metal grid 174 instead of Figure 6 The first metal grid 173 may correspond to the metal grid 172 of the image sensor 100. Figure 6 In addition to the first metal mesh 173, the second metal mesh 174 may be a portion of the metal mesh 172 disposed at the interface between the first PD region AR1 and the second PD region AR2. Figure 6 The first metal grid 173 may be a portion covered by the beam splitter LS, and the second metal grid 174 may be a portion not covered by the beam splitter LS. Figure 6 Unlike the metal mesh 172 in the embodiment, the second metal mesh 174 may include a first portion 175 and a second portion 176. The first portion 175 and the second portion 176 may include materials having different refractive indices. The first metal mesh 173 may include the same material as the first portion 175. The second portion 176 may include an insulator or semiconductor material having a low refractive index, rather than a metal.

[0113] and Fig.16 Like the beam splitter LS of the image sensor 100i in FIG. 1 , the beam splitter LS of the image sensor 100j may be located between the substrate 101 and the color filter 170. The beam splitter LS may directly cover the upper surface of the substrate 101. The beam splitter LS may cover at least a portion of the first metal grid 173. The microlens 180 may be separated from the beam splitter LS. The color filter 170 may cover the upper surface and the side surface of the beam splitter LS.

[0114] The beam splitter LS may include the same material as the second portion 176. For this reason, when the first metal mesh 173 and the second metal mesh 174 are formed, the beam splitter LS may also be formed together. That is, the manufacturing process of the image sensor 100j may be facilitated.

[0115] Fig.18is a top view of an image sensor 100 k according to some example embodiments. Fig.19 is a diagram of an image sensor 100k according to some example embodiments, and is Fig.18 A cross-sectional view taken along line CC'. Figure 5 and Figure 6 The descriptions that are identical are given, and only the differences are described in detail.

[0116] Reference Fig.18 and Fig.19 , the image sensor 100k may further include a filler 178 and a light-blocking film LSF in the second PD region AR2. The filler 178 may be disposed on the upper surface of the substrate 101. The filler 178 may be disposed on the side of the beam splitter LS. The filler 178 may be located between the light-blocking film LSF and the substrate 101. The filler 178 may include an insulating material such as silicon oxide, silicon nitride, and / or silicon oxynitride. Alternatively, the filler 178 may include the same material as that of the color filter 170.

[0117] The light-blocking film LSF may be disposed on the beam splitter LS and the filler 178. The light-blocking film LSF may cover the second PD region AR2. The vertical level of the upper surface of the light-blocking film LSF may be the same as the vertical level of the upper surface of the color filter 170, or lower or higher than the vertical level of the upper surface of the color filter 170. The microlens 180 may cover a portion of the light-blocking film LSF. The light-blocking film LSF may include a metal such as W, Al, and / or Cu.

[0118] Due to the presence of the light blocking film LSF, light can be limited or prevented from directly entering the second PD (SPD), so the color filter 170 can be set only in the first PD area AR1. Accordingly, the amount of light transmitted to the second PD area AR2 can be more effectively adjusted, and therefore, the sensitivity of the second PD (SPD) can be easily adjusted.

[0119] Fig. 20 is a top view of an image sensor 1001 according to some example embodiments. Fig.21 is a diagram of an image sensor 1001 according to some example embodiments, and is Fig. 20 A cross-sectional view taken along line D-D'. Figure 5 and Figure 6 The descriptions that are identical are given, and only the differences are described in detail.

[0120] Reference Fig. 20 and Fig.21, the microlens 180 of the image sensor 1001 may include an opening 180H. In a top view, the opening 180H may be formed at the center of the microlens 180 (or the center of the first PD area AR1). The microlens 180 may have a donut shape. In a top view, the microlens 180 may have an annular shape. At least a portion of the beam splitter LS may be exposed to the outside through the opening 180H in the first PD area AR1. In other words, at least a portion of the beam splitter LS may vertically overlap with the opening 180H in the first PD area AR1.

[0121] The cross-sectional shape of the microlens 180 excluding the opening 180H may be a portion of a circle. In some example embodiments, the cross-sectional shape of the microlens 180 may be a semicircle.

[0122] Since the opening 180H is formed at the center of the first PD region AR1, the amount of light incident to the beam splitter LS in the first PD region AR1 can be reduced. That is, by forming the opening 180H, the amount of light transmitted to the second PD (SPD) can be adjusted.

[0123] Fig. 22 is a top view of an image sensor 100 m according to some example embodiments. Fig.23 is a top view of an image sensor 100n according to some example embodiments. Fig.24 is a top view of an image sensor 100o according to some example embodiments. Figure 5 and Figure 6 The descriptions that are identical are given, and only the differences are described in detail.

[0124] Reference Fig. 22 , Fig.23 and Fig.24 And through Fig. 20 In contrast, the positions of the openings 180H formed in the microlenses 180 of the image sensors 100m, 100n, and 100o may be changed differently. Fig. 22 As shown in FIG. 1 , the opening 180H of the microlens 180 may be formed closer to the second PD area AR2 than the center of the first PD area AR1. Fig.23 As shown in FIG. 1 , the opening 180H of the microlens 180 may be formed to be away from the center of the first PD region AR1 in a direction away from the second PD region AR2. Accordingly, the area of ​​the beam splitter LS vertically overlapping the opening 180H may be increased or decreased. Alternatively, as Fig.24As shown in , while reducing the length of the beam splitter LS, the plane position of the opening 180H can also vertically overlap at least a portion of the beam splitter LS. The amount of light transmitted to the second PD (SPD) can be adjusted by determining the position of the opening 180H and adjusting the length of the beam splitter LS as described above.

[0125] Fig.25 is a top view of an image sensor 100p according to some example embodiments. Fig.26 is a view of an image sensor 100p according to some example embodiments, and is Fig.25 A cross-sectional view taken along line EE'. Figure 5 and Figure 6 The descriptions that are identical are given, and only the differences are described in detail.

[0126] Reference Fig.25 and Fig.26 , the image sensor 100p may include a first beam splitter section LS8 and a second beam splitter section LS9 instead of Figure 5 and Figure 6 The first beam splitter portion LS8 may be located between the substrate 101 and the color filter 170 in the first PD area AR1. The second beam splitter portion LS9 may be located between the substrate 101 and the color filter 170 in the second PD area AR2. The first beam splitter portion LS8 may have a triangular cross-sectional shape. The second beam splitter portion LS9 may have a shape such as a cylindrical column, an elliptical column, a quadrilateral column, or a polygonal column. The first beam splitter portion LS8 may be used as a prism. That is, light incident on the first PD area AR1 may be transmitted to the first beam splitter portion LS8, and the light is reflected and refracted inside the first beam splitter portion LS8, and is transmitted to the second beam splitter portion LS9 in the second PD area AR2. The light transmitted to the second beam splitter portion LS9 may be reflected and refracted to be transmitted to the second PD (SPD). The first beam splitter portion LS8 and the second beam splitter portion LS9 may include Figure 5 and Figure 6 The material of the beam splitter LS is the same material.

[0127] Fig. 27 is a top view of an image sensor 100q according to some example embodiments. Fig.28 is a view of an image sensor 100q according to some example embodiments, and is Fig. 27 A cross-sectional view taken along line F-F'. Figure 5 and Figure 6 The descriptions that are identical are given, and only the differences are described in detail.

[0128] Reference Fig. 27 and Fig.28 , the beam splitter LS of the image sensor 100q may include mesa-shaped structures LSa, LSb, LSc, and LSd. Here, the image sensor 100q may not include the microlens 180. The mesa shape may refer to a shape having a flat upper surface and a right-angled or steep side surface. For example, the mesa shape may include a cylinder. Fig. 27 , the planar shape of the structures LSa, LSb, LSc, and LSd is shown as a circle, but is not limited thereto. Each of the structures LSa, LSb, LSc, and LSd may have various shapes such as an ellipse, a triangle, a quadrilateral, and / or a polygon. Accordingly, the table shape may have various shapes such as an elliptical column, a triangular column, a quadrilateral column, and / or a polygonal column.

[0129] The structures LSa, LSb, LSc, and LSd can be separated from each other. The distance between the structures LSa, LSb, LSc, and LSd can be freely adjusted. The horizontal area of ​​each of the structures LSa, LSb, LSc, and LSd can also be freely adjusted. By adjusting the distance between the structures LSa, LSb, LSc, and LSd and the horizontal area of ​​each of the structures LSa, LSb, LSc, and LSd, light incident on the first PD area AR1 can be transmitted to the second PD area AR2 by reflection and refraction. That is, by adjusting the shape and distance of the structures LSa, LSb, LSc, and LSd, the spectrometer LS of the image sensor 100q can perform the same Figure 5 and Figure 6 The same function as the beam splitter LS in (light distribution function).

[0130] The structures LSa, LSb, LSc and LSd of the beam splitter LS of the image sensor 100q may include Figure 5 and Figure 6 The material included in the spectrometer LS of the image sensor 100 is the same material.

[0131] Fig.29 is a top view of an image sensor 100r according to some example embodiments. Fig.30 is a view of an image sensor 100r according to some example embodiments, and is Fig.29 A cross-sectional view taken along line G-G'. Figure 5 and Figure 6 The descriptions that are identical are given, and only the differences are described in detail.

[0132] Reference Fig.29 and Fig.30 , can be omitted Figure 5 and Figure 6Alternatively, a void VD may be formed inside the microlens 180 of the image sensor 100r. The void VD may be an empty space inside the microlens 180. For example, the void VD may include an air gap. Gas atoms or molecules may be included in the void VD. The refractive index of the void VD may be different from the refractive indexes of the microlens 180 and the color filter 170.

[0133] The light entering the microlens 180 may be incident into the void VD, and is repeatedly reflected by the interface between the void VD and the microlens 180 and the interface between the void VD and the color filter 170, and may move from the first PD (LPD) to the second PD (SPD). The light moving to the second PD (SPD) may leave the void VD and may be incident on the second PD (SPD). Accordingly, the void VD of the image sensor 100r may perform the same Figure 5 and Figure 6 That is, the void VD of the image sensor 100r may perform a function of distributing light incident on the first PD area AR1 to the second PD area AR2.

[0134] The shape of the gap VD can vary. Fig.29 and Fig.30 , the plane shape and cross-sectional shape of the void VD are represented as a rectangle, but the inventive concept is not limited thereto. The plane and / or cross-sectional shape of the void VD may be changed to various shapes such as a circle, an ellipse, and a polygon. For example, the void VD may have a hemispherical shape. This may vary depending on the design of the image sensor 100r to be implemented.

[0135] One or more of the elements disclosed above may include a processing circuit (such as hardware including a logic circuit; a hardware / software combination such as a processor that executes software; or a combination thereof), or be implemented in a processing circuit. For example, the processing circuit may more specifically include, but is not limited to, a central processing unit (CPU), an arithmetic logic unit (ALU), a digital signal processor, a microcomputer, a field programmable gate array (FPGA), a system on a chip (SoC), a programmable logic unit, a microprocessor, an application specific integrated circuit (ASIC), etc.

[0136] While the inventive concept has been particularly shown and described with reference to embodiments thereof, it will be understood that various changes in form and details may be made therein without departing from the spirit and scope of the appended claims.

Claims

1. An image sensor, comprising: A substrate, the substrate comprising a first PD region and a second PD region adjacent to the first PD region, the PD being a photodiode; A first PD, the first PD has a first area, and the first PD is located in the first PD region; a second PD, the second PD having a second area smaller than the first area, the second PD being located in the second PD region; a microlens, the microlens being located on the substrate and covering the first PD region; and a beam splitter located between the substrate and the microlens and comprising a material having a refractive index different from that of the microlens, The optical splitter extends from the first PD area to the second PD area.

2. The image sensor according to claim 1, wherein: The first PD region includes a central portion and an edge portion surrounding the central portion, and A horizontal area of ​​the beam splitter in the second PD region is larger than a horizontal area of ​​the beam splitter in an edge portion of the first PD region.

3. The image sensor according to claim 1, wherein: The first PD region includes a central portion and an edge portion surrounding the central portion, and A horizontal area of ​​the beam splitter in a central portion of the first PD region is larger than a horizontal area of ​​the beam splitter in an edge portion of the first PD region.

4. The image sensor according to claim 1, wherein: The optical splitter includes at least one of TiO2, SiO2, SiN and amorphous silicon.

5. The image sensor according to claim 1, wherein: A direction parallel to the upper surface of the substrate and from the central portion of the first PD region to the central portion of the second PD region is defined as a first direction, A direction parallel to the upper surface of the substrate and perpendicular to the first direction is defined as a second direction, and The beam splitter has a varying thickness in the second direction from a central portion of the first PD to a central portion of the second PD along the first direction.

6. The image sensor according to claim 1, further comprising: A deep trench isolation separates the first PD region from the second PD region, and the optical splitter vertically overlaps at least a portion of the deep trench isolation.

7. The image sensor according to claim 6, further comprising: A metal grid is located between the substrate and the microlens and vertically overlaps at least a portion of the deep trench isolation, wherein the metal grid is separated from the beam splitter in a top view.

8. The image sensor according to claim 6, further comprising: A metal grid is located between the substrate and the microlens and vertically overlaps the deep trench isolation, wherein the beam splitter covers at least a portion of the metal grid.

9. The image sensor according to claim 1, further comprising: a light-blocking film, wherein the light-blocking film covers the second PD region on the beam splitter, Wherein, the light-blocking film comprises metal.

10. The image sensor according to claim 1, wherein: The microlens includes an opening in the first PD region that exposes at least a portion of the beam splitter, and The microlens has a ring shape in a top view.

11. An image sensor, comprising: A substrate, in which a first PD region and a second PD region are defined, wherein the PD is a photodiode; a first PD, the first PD having a first area in the substrate, the first PD being located in the first PD region; a second PD having a second area in the substrate that is smaller than the first area and located in the second PD region; a color filter, the color filter being located on the substrate; and a beam splitter, the beam splitter being located between the substrate and the color filter, or being located on the color filter, wherein the beam splitter comprises a material having a refractive index different from that of the color filter, and The beam splitter vertically overlaps at least a portion of the first PD region and at least a portion of the second PD region.

12. The image sensor according to claim 11, wherein: The beam splitter is located on the color filter.

13. The image sensor according to claim 12, further comprising: a microlens, wherein the microlens is located on the beam splitter, The microlens exposes at least a portion of the beam splitter.

14. The image sensor according to claim 12, wherein: The beam splitter includes mesa-shaped structures, and the mesa-shaped structures are separated from each other.

15. The image sensor according to claim 11, wherein: The beam splitter is located between the substrate and the color filter.

16. The image sensor according to claim 15, wherein: The beam splitter includes a first beam splitter portion vertically overlapping the first PD region and a second beam splitter portion vertically overlapping the second PD region, The first beam splitter portion is separated from the second beam splitter portion, and The cross-sectional shape of the first beam splitter portion is a triangle.

17. The image sensor according to claim 11, further comprising: a microlens, wherein the microlens is located on the color filter, wherein the microlens covers the entire first PD region, and The microlens vertically overlaps at least a portion of the second PD region.

18. The image sensor according to claim 17, wherein: The microlens exposes at least a portion of the color filter.

19. An image sensor, comprising: A substrate, the substrate comprising a first PD region and a second PD region adjacent to the first PD region, the PD being a photodiode; a first PD, the first PD is located in the first PD region, and the first PD has a first area; a second PD, the second PD being located in the second PD region and having a second area smaller than the first area; a deep trench isolation that separates the first PD region from the second PD region and passes through the substrate; a microlens, the microlens being located on the substrate and covering the first PD area; a color filter, the color filter being located between the substrate and the microlens; a beam splitter, the beam splitter being located between the substrate and the color filter, or between the color filter and the microlens; and an interconnection layer, the interconnection layer being located below the substrate, the interconnection layer comprising an insulating film and a conductive interconnection located in the insulating film, wherein the optical splitter vertically overlaps at least a portion of the first PD region and at least a portion of the second PD region, and The beam splitter has a refractive index different from those of the microlens and the color filter.

20. The image sensor according to claim 19, wherein: The image sensor includes a plurality of pixels arranged in a two-dimensional array structure, the first PD region has an octagonal shape in a plane, and the second PD region has a quadrilateral shape in a plane, The first PD region is selected from a plurality of first PD regions, and the second PD region is selected from a plurality of second PD regions, and Four first PD areas among the plurality of first PD areas surround one second PD area among the plurality of second PD areas, and four second PD areas among the plurality of second PD areas are arranged alternately on four sides among eight sides of one first PD area among the plurality of first PD areas.

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