Image sensing device

Abstract

An image sensing device is disclosed. In one embodiment, an image sensing device includes a unit pixel and a pixel isolator. The unit pixel includes a first photoelectric conversion region and a second photoelectric conversion region spaced apart from each other in a substrate. The substrate includes a first surface configured to receive incident light and a second surface facing or opposite to the first surface. The pixel isolator is disposed in a trench recessed from the second surface into the substrate and includes a first insulating region having a first width and a second insulating region having a second width different from the first width and disposed between the first and second photoelectric conversion regions.

Description

Technical Field

[0001] The technology and implementation disclosed in this patent document generally relate to an image sensing device capable of generating image data by sensing light. Background Technology

[0002] Image sensing devices capture optical images by converting light into electrical signals using photosensitive semiconductor materials that react to light. With advancements in industries such as automotive, medical, computer, and communications, the demand for high-performance image sensing devices is growing across a wide range of fields, including smartphones, digital cameras, gaming consoles, IoT (Internet of Things), robotics, security cameras, and medical miniature cameras.

[0003] Image sensing devices can be broadly categorized into charge-coupled device (CCD) image sensing devices and complementary metal-oxide-semiconductor (CMOS) image sensing devices. Compared to CMOS image sensing devices, CCD image sensing devices offer better image quality, but they tend to consume more power and are larger. CMOS image sensing devices, on the other hand, are smaller and consume less power than CCD image sensing devices. Furthermore, CMOS sensors are manufactured using CMOS fabrication technology, allowing the photosensitive element and other signal processing circuitry to be integrated into a single chip, thus enabling the production of miniaturized image sensing devices at a lower cost. For these reasons, CMOS image sensing devices are being developed for many applications, including mobile devices. Summary of the Invention

[0004] Various embodiments of the disclosed technology relate to an image sensing device with improved autofocus performance.

[0005] Various embodiments of the disclosed technology relate to an image sensing device with improved yield.

[0006] In an embodiment of the disclosed technology, an image sensing device may include: a substrate including a first surface configured to receive incident light and a second surface opposite to the first surface; a unit pixel supported by the substrate and including a first photoelectric conversion region configured to generate an electrical signal in response to incident light and a second photoelectric conversion region spaced apart from the first photoelectric conversion region and configured to generate an electrical signal in response to incident light; and a pixel isolator disposed in a trench recessed from the second surface into the substrate, the pixel isolator including a first insulating region having a first width along a direction parallel to the substrate and a second insulating region having a second width different from the first width, wherein the second insulating region is disposed between the first photoelectric conversion region and the second photoelectric conversion region.

[0007] In another embodiment of the disclosed technology, an image sensing device may include: a unit pixel comprising a first semiconductor region, a second semiconductor region, and a semiconductor bridging region, the first semiconductor region including a first photoelectric conversion region configured to detect light, the second semiconductor region including a second photoelectric conversion region configured to detect light and spaced apart from the first semiconductor region in a first direction, the semiconductor bridging region connecting the first semiconductor region and the second semiconductor region; and a pixel separator formed around the unit pixel and configured to include a first insulating region and a second insulating region, the first insulating region having a first width and disposed along a side surface of the unit pixel, the second insulating region having a second width less than the first width and disposed along another side surface of the unit pixel.

[0008] In another embodiment of the disclosed technology, an image sensing device may include: a substrate including a first surface configured to receive incident light and a second surface opposite to the first surface; a unit pixel supported by the substrate and including a first semiconductor region, a second semiconductor region, and a semiconductor bridging region, the first semiconductor region including a first photoelectric conversion region configured to detect light, the second semiconductor region including a second photoelectric conversion region configured to detect light, the second semiconductor region being spaced apart from the first semiconductor region in a first direction, and the semiconductor bridging region being disposed between the first semiconductor region and the second semiconductor region; a pixel separator disposed in a trench recessed from the second surface into the substrate and including an insulating layer surrounding the unit pixel and a filler layer surrounding the insulating layer; and an interconnect layer disposed on the second surface of the substrate, wherein the insulating layer includes a first insulating region and a second insulating region, the first insulating region having a first thickness in an outer peripheral region, and the second insulating region having a second thickness in a protrusion region extending from the outer peripheral region into the semiconductor bridging region in a second direction perpendicular to the first direction.

[0009] It will be understood that the above general description and the following detailed description of the disclosed technology are both illustrative and explanatory, intended to provide further explanation of the claimed disclosed technology. Attached Figure Description

[0010] The above and other features and advantages of the disclosed technology will become readily apparent when considered in conjunction with the accompanying drawings, with reference to the following detailed description.

[0011] Figure 1 This is a schematic diagram illustrating an example of an image sensing device based on some implementations of the disclosed technology.

[0012] Figure 2 This is a circuit diagram illustrating an example of a unit pixel included in an image sensing device based on some embodiments of the disclosed technology.

[0013] Figure 3 This is a plan view illustrating an example of an image sensing device based on some implementations of the disclosed technology.

[0014] Figure 4A and Figure 4B This is a cross-sectional view illustrating an example of an image sensing device based on some implementations of the disclosed technology.

[0015] Figure 5 This is a plan view illustrating an example of an image sensing device based on some implementations of the disclosed technology.

[0016] Figure 6 This is a plan view illustrating an example of an image sensing device based on some implementations of the disclosed technology.

[0017] Figure 7 This is a plan view illustrating an example of an image sensing device based on some implementations of the disclosed technology.

[0018] Figures 8A to 8D This is a cross-sectional view illustrating an example of a method for manufacturing an image sensing device based on some embodiments of the disclosed technology. Detailed Implementation

[0019] This patent document provides implementations and examples of an image sensing device capable of generating image data by sensing light, which can be used in a configuration that substantially solves one or more technical or engineering problems and mitigates some limitations or disadvantages encountered in other image sensing devices. Some implementations of the disclosed technology relate to an image sensing device with improved autofocus performance. Some implementations of the disclosed technology relate to an image sensing device with improved yield. Recognizing the above-mentioned problems, some embodiments of the disclosed technology provide an image sensing device in which the insulating layer surrounding a unit pixel can have different widths depending on the location of the insulating layer. This configuration reduces the difficulty of forming impurity regions, thereby enhancing manufacturing efficiency. The disclosed technology provides an image sensing device with higher autofocus performance by relatively increasing the doping concentration of the impurity regions. Some embodiments of the disclosed technology provide an image sensing device with a region where the width of the insulating layer varies depending on the type of unit pixel, thereby allowing the image sensing device to have more uniform sensitivity across the image sensing device.

[0020] Reference will now be made in detail to embodiments of the disclosed technology, examples of which are illustrated in the accompanying drawings. Wherever possible, the same reference numerals will be used throughout the drawings to denote the same or similar parts. While the disclosed technology is readily adapted to various modifications and alternatives, specific embodiments are shown in the drawings as examples. However, the disclosed technology should not be construed as being limited to the embodiments set forth herein.

[0021] Various embodiments will be described below with reference to the accompanying drawings. However, it should be understood that the disclosed technology is not limited to specific embodiments, but includes various modifications, equivalents, and / or substitutions of the embodiments. Embodiments of the disclosed technology can provide various effects that can be directly or indirectly identified by the disclosed technology.

[0022] Figure 1 This is a schematic diagram illustrating an example of an image sensing device 1 based on some implementations of the disclosed technology.

[0023] Reference Figure 1 The image sensing device 1 according to an exemplary embodiment of the disclosed technology may include a timing control circuit 110, a drive control circuit 120, a pixel array 130, and a readout circuit 140. Figure 1 The components of the image sensing device 1 shown are discussed only as examples, and this patent document covers numerous other changes, substitutions, variations, alterations, and modifications. In some embodiments described in this patent document, the term "pixel" may be used to refer to an image sensing pixel configured to detect incident light to generate an electrical signal carrying an image in the incident light.

[0024] The timing control circuit 110 can provide timing signals and control signals to at least one of the drive control circuit 120 and the readout circuit 140.

[0025] The drive control circuit 120 can enable the pixel array 130 to perform specific operations on the pixels included in the corresponding rows based on timing signals and control signals provided from the timing control circuit 110.

[0026] In some implementations, the drive control circuit 120 may select at least one pixel in at least one row of the pixel array 130 and may provide the selected pixel with a control signal for performing a specific operation. The drive control circuit 120 may generate a row selection signal to select at least one row from multiple rows. When the drive control circuit 120 selects a specific row from multiple rows to perform a specific operation, the drive control circuit 120 may not perform the specific operation on rows adjacent to the selected specific row.

[0027] The pixels in the row selected by the drive control circuit 120 can sequentially transmit analog reference signals and image signals to the readout circuit 140. The reference signal can be an electrical signal provided to the readout circuit 140 when the floating diffusion region of each pixel is reset to the power supply voltage VDD. The image signal can be an electrical signal provided to the readout circuit 140 when the photocharge generated by each pixel accumulates in the floating diffusion region (FD).

[0028] The reference signal can be a signal that indicates the unique pixel noise of each pixel. The reference signal and the image signal can be collectively referred to as the pixel signal as needed.

[0029] Pixel array 130 may include a plurality of pixels arranged in multiple rows and columns. The plurality of pixels may be connected to drive control circuitry 120 via multiple row lines extending in the row direction. The plurality of pixels may be connected to readout circuitry 140 via multiple column lines extending in the column direction. Pixel array 130 may include at least one pixel 200 arranged in both the row and column directions. For example, pixel array 130 may be arranged as a two-dimensional (2D) pixel array (or matrix configuration) where the plurality of unit pixels comprise rows and columns.

[0030] Multiple unit pixels included in pixel array 130 can convert optical signals into electrical signals (pixel signals) and can be connected to specific internal pixel circuits.

[0031] The pixel array 130 can receive pixel control signals, including selection signals, reset signals, transfer signals, etc., from the drive control circuit 120. At least one pixel in the row selected by the drive control circuit 120 according to the pixel control signals can perform a specific operation in response to the selection signal, reset signal, and transfer signal.

[0032] Each of the plurality of pixels included in the pixel array 130 can output a pixel signal in response to incident light received from the outside. Each of the plurality of pixels can be arranged in a two-dimensional (2D) structure. For example, each of the plurality of pixels can be arranged in a matrix structure. The plurality of pixels can be arranged in a first direction and a second direction. For example, the plurality of pixels can be arranged in the row direction and the column direction.

[0033] Of the light incident on a pixel, light of a specific wavelength (e.g., red, green, or blue light) can pass through filters arranged in the active pixel, and the light passing through the filters can be focused onto at least one photoelectric conversion element. The photoelectric conversion element can generate photocharge in response to the incident light. An electrical signal can be generated by the pixel in response to the amount of photocharge generated.

[0034] When a pixel operates under conditions where the amount of incident light is very small or there is no incident light (hereinafter referred to as dark conditions), the pixel can generate a dark signal. The signal generated under dark conditions can be a signal corresponding to the noise component generated inside the image sensing device 1.

[0035] As the number of pixels included in pixel array 130 increases and the area of ​​the entire pixel array 130 increases, the deviation of the noise component of the pixels may increase depending on the position of the pixels in pixel array 130. As the deviation of the noise component increases, the quality of the image obtained from the multiple pixel signals generated from pixel array 130 may decrease.

[0036] The readout circuit 140 can sample the electrical signals output from the pixel array 130, convert the sampled electrical signals into digital signals, and output the digital signals to an image signal processor (ISP). The readout circuit 140 may include, for example, a correlated dual sampler (CDS), an analog-to-digital converter (ADC), an output buffer, a column driver, etc.

[0037] For example, the CDS can receive reference signals and image signals, each corresponding to a column of the pixel array 130, and can sample the levels of the reference signals and image signals. In an image sensing device designed to use CMOS, the CDS can sample the pixel signal twice to remove the difference between the two samples, and can perform correlated double sampling to remove unwanted offset values ​​(such as fixed noise) of the pixel. For example, the CDS can compare the pixel output voltage obtained before and after the photocharge generated by the incident light accumulates in the floating diffusion region to remove unwanted offset values, so that the pixel output voltage based on the incident light can be measured.

[0038] The CDS can send the reference signal and image signal generated by the timing signal and control signal based on the timing control circuit 110 in the column as a CDS signal to the ADC.

[0039] An ADC can convert analog CDS signals received from a CDS into digital signals and output the resulting digital signals.

[0040] The output buffer can temporarily store and output digital signals provided by the ADC.

[0041] The column driver can select columns from the output buffer based on the timing signal and control signal of the timing control circuit 110, and can control the temporarily stored digital signals to be output according to the selection order.

[0042] Figure 2 This is a circuit diagram illustrating an example of a unit pixel (PX) included in an image sensing device 1 based on some embodiments of the disclosed technology.

[0043] Reference Figure 2 In pixel array 130 (see Figure 1 The array includes unit pixels (PX), and multiple unit pixels can be represented in pixel array 130 (see [link]). Figure 1 The rows and columns are arranged repeatedly.

[0044] A unit pixel (PX) may include a first photoelectric conversion element (PD1), a second photoelectric conversion element (PD2), a first transfer transistor (TX1), a second transfer transistor (TX2), a reset transistor (RX), an amplification transistor (SF), and a selection transistor (SX). However, unlike the example shown, in some other implementations, at least one of the reset transistor (RX), amplification transistor (SF), and selection transistor (SX) may be omitted from the unit pixel (PX), or additional transistors may be included in the unit pixel (PX).

[0045] The first photoelectric conversion element (PD1) and the second photoelectric conversion element (PD2) can generate photocharge in response to incident light, and the amount of photocharge generated varies according to the intensity of the received incident light. For example, the first photoelectric conversion element (PD1) and the second photoelectric conversion element (PD2) can be PN junction photodiodes and can be constructed and operated to generate photocharge proportional to the amount of incident light. Each of the first photoelectric conversion element (PD1) and the second photoelectric conversion element (PD2) can be implemented in various photosensitive devices, such as phototransistors, light gates, pinned photodiodes, or combinations thereof. Figure 2 In the example, a unit pixel (PX) processing uses a combination of photocharges (e.g., electrons) generated by two photoelectric conversion elements, and outputs an electrical signal as a unit pixel output of electrons from the two photoelectric conversion elements, which can improve the performance of the image sensing device.

[0046] exist Figure 2In the example, a common floating diffusion region (FD) is provided to collect photocharge from two photoconversion elements PD1 and PD2. A first transfer transistor (TX1) is connected to the first photoconversion element (PD1) to transfer the photocharge generated by the first photoconversion element (PD1) to the floating diffusion region (FD) in response to a first transfer control signal (TS1). A second transfer transistor (TX2) is connected to the second photoconversion element (PD2) to transfer the photocharge generated by the second photoconversion element (PD2) to the floating diffusion region (FD) in response to a second transfer control signal (TS2). When each of the first transfer transistor (TX1) and the second transfer transistor (TX2) is turned on, the photocharge generated by each of the first photoconversion element (PD1) and the second photoconversion element (PD2) can be transferred to a floating diffusion region (FD) and can be accumulated and stored in the floating diffusion region (FD).

[0047] A reset transistor (RX) can be coupled to the floating diffusion region (FD) to periodically reset the photocharge accumulated in the FD after each readout, preparing the unit pixel PX for the next cycle of photosensitivity operation. The drain electrode of the reset transistor (RX) can be connected to the FD, and the source electrode can be connected to the power supply voltage (VPIX). When the reset transistor (RX) is turned on according to the reset control signal (RS), the power supply voltage (VPIX) connected to the source electrode of the reset transistor (RX) can be transferred to the FD. When the reset transistor (RX) is turned on, the photocharge accumulated in the FD is discharged, allowing the FD to be reset.

[0048] The amplifying transistor (SF) can be used as a buffer amplifier and can buffer the signal based on the photocharge accumulated in the floating diffusion region (FD). The amplifying transistor (SF) can be controlled according to the amount of photocharge accumulated in the floating diffusion region (FD). The amplifying transistor (SF) can amplify the potential changes in the floating diffusion region (FD) and output the amplified potential changes as a pixel signal (VOUT) to the column output line.

[0049] The drain terminal of the select transistor (SX) is connected to the source terminal of the amplifying transistor (SF), and the select transistor (SX) is responsive to the select signal (SELS) via the column output line. Figure 1 The CDS output pixel signal (VOUT) described in the document.

[0050] Although for ease of description, the above embodiments disclose an example in which the photocharge generated by each of the first photoelectric conversion element (PD1) and the second photoelectric conversion element (PD2) accumulates in the same floating diffusion region (FD), other implementations are also possible. According to other embodiments, the photocharge generated by the first photoelectric conversion element (PD1) can accumulate in the first floating diffusion region, and the photocharge generated by the second photoelectric conversion element (PD2) can accumulate in a second floating diffusion region separate from the first floating diffusion region.

[0051] Figure 3 This is a plan view illustrating an example of an image sensing device 300 based on some embodiments of the disclosed technology. Figure 4A and Figure 4B Show Figure 3 A cross-sectional view of an example of an image sensing device 300. Figure 3 , Figure 4A and Figure 4B The substrate includes a first surface configured in the xy plane to receive incident light and a second surface on the opposite side of the first surface in the xy plane. For example... Figure 4A and Figure 4B As shown, the substrate is represented by substrate layer 310, which has a first surface (310a) on which light is incident and a second surface (310b) facing the first surface (310a) or opposite to the first surface (310a). Various circuit elements (e.g., transistors) per unit pixel are formed or supported on the second surface (310b).

[0052] Reference Figure 3 The image sensing device 300 is included as Figure 1 The image sensing device 1 shown is a part of a substrate, a plurality of unit pixels (e.g., UP1, UP2, UP3 and UP4) supported by the substrate, and a pixel separator 320 supported by the substrate and configured to define and isolate the plurality of unit pixels.

[0053] In this example, a unit pixel is the basic unit used to detect incident light, and different unit pixels together form a two-dimensional pixel array 130 (see [reference]). Figure 1 This is used to sense incident light in order to capture the image carried by the incident light. Figure 3 In the example, four unit pixels (i.e., the first to fourth unit pixels UP1, UP2, UP3, and UP4) are arranged in pixel array 130 in the magnified image (see [link]). Figure 1It is shown as a portion of a plurality of unit pixels in ). Adjacent unit pixels among the first to fourth unit pixels (UP1, UP2, UP3, UP4) may be arranged side by side in a first direction (e.g., the X-axis direction) or in a second direction perpendicular to the first direction (e.g., the Y-axis direction).

[0054] Each of the first to fourth unit pixels (UP1, UP2, UP3, UP4) can be any one of a red pixel, a green pixel, a blue pixel, and a white pixel. A red pixel can be a pixel that transmits a specific wavelength of red light incident on the unit pixel through a color filter and focuses the red light onto the photoelectric conversion element. Similarly, green, blue, and white pixels can be pixels that converge light of a specific wavelength (e.g., green, blue, or white light) onto the photoelectric conversion element. For example, red, green, blue, and white pixels can be distinguished from each other based on the type of color filter used in the corresponding unit pixel.

[0055] In some implementations, a group of four adjacent unit pixels with different color filters can collectively form a pixel group for capturing the color information of the image carried by incident light. For example, the first to fourth unit pixels (UP1, UP2, UP3, UP4) can form a color-sensing pixel group, where the second unit pixel (UP2) has a red filter as a red pixel for sensing red light in the incident light, the third unit pixel (UP3) has a blue filter as a blue pixel for sensing blue light in the incident light, and each of the first unit pixel (UP1) and the fourth unit pixel (UP4) has a green filter as a green pixel for sensing green light in the incident light. This color filter arrangement forms a Bayer pattern to capture the color information of the image. However, the arrangement of these pixels is not limited to this and can be changed in various ways.

[0056] Each of the first to fourth unit pixels (UP1, UP2, UP3, UP4) is formed on or supported by a substrate, and may have substantially the same characteristics except for some structures (e.g., the type of color filter). For ease of description, the following description will focus on the first unit pixel (UP1). In some embodiments described in this specification, the "first unit pixel" may be referred to as a "unit pixel". In some embodiments described in this specification, each of the "second unit pixel" or "third unit pixel" may be referred to as an "adjacent unit pixel".

[0057] The first unit pixel (UP1) may include: a first semiconductor region (310r1) having a first photoelectric conversion region (PD1) (e.g., a photodetector) that generates photocharge in response to incident light; a second semiconductor region (310r2) having a second photoelectric conversion region (PD2) (e.g., a photodetector) that generates photocharge in response to incident light; and a semiconductor bridging region (310br) located between the first semiconductor region (310r1) and the second semiconductor region (310r2). The first photoelectric conversion region (PD1) and the second photoelectric conversion region (PD2) may be connected to... Figure 2 The area described in the text is essentially the same area, and the first unit pixel (UP1) can be a 2PD pixel including two photoelectric conversion elements.

[0058] The first semiconductor region (310r1) and the second semiconductor region (310r2) may be arranged spaced apart from each other in a first direction (e.g., the X-axis direction). Additionally, the first photoelectric conversion region (PD1) may be arranged spaced apart from the second photoelectric conversion region (PD2) in the first direction (X). The first semiconductor region (310r1) may extend parallel to the second semiconductor region (310r2) in a second direction perpendicular to the first direction (X) (e.g., the Y-axis direction).

[0059] A semiconductor bridging region (310br) can connect a first semiconductor region (310r1) and a second semiconductor region (310r2) to each other. In the second direction (Y), the length of the semiconductor bridging region (310br) may be shorter than the length of the first semiconductor region (310r1) and / or the length of the second semiconductor region (310r2). The first semiconductor region (310r1) may include a portion extending in the second direction (Y) from the portion connected to the semiconductor bridging region (310br). The second semiconductor region (310r2) may include a portion extending in the second direction (Y) from the portion connected to the semiconductor bridging region (310br). In some implementations, the first semiconductor region (310r1), the second semiconductor region (310r2), and the semiconductor bridging region (310br) may be connected to each other to have an "H" shape.

[0060] Pixel spacers 320 surround the first to fourth unit pixels (UP1, UP2, UP3, UP4) and separate the unit pixels from each other. Since the first to fourth unit pixels (UP1, UP2, UP3, UP4) are spaced apart by pixel spacers 320, each unit pixel can be defined by pixel spacers 320. Pixel spacers 320 prevent photocharge generated by incident light incident on each unit pixel from moving to adjacent unit pixels due to random drift. Therefore, pixel spacers 320 prevent crosstalk between adjacent unit pixels and improve image sensing.

[0061] Pixel spacers 320 may include a peripheral region (320s) surrounding the first to fourth unit pixels (UP1, UP2, UP3, UP4) and a protruding region (320p) extending toward each of the semiconductor bridging regions (310br) of the first to fourth unit pixels (UP1, UP2, UP3, UP4). (See also...) Figure 3 The peripheral region (320s) and the protruding region (320p) can be regions separated on a plane at a specific distance relative to the pixel separator 320 of the separated unit pixel, and each unit pixel includes a first semiconductor region (310r1), a second semiconductor region (310r2) and a semiconductor bridging region (310br).

[0062] Therefore, the peripheral region (320s) and the protruding region (320p) can be integrally connected regions. The protruding region (320p) can extend from the peripheral region (320s) in a second direction (Y). In some implementations, the protruding region (320p) can include a first protruding region (320p1) and a second protruding region (320p2) spaced apart from each other in the second direction (Y) based on semiconductor bridging regions (310br) of the unit pixels interposed therebetween. In some implementations, each of the first to fourth unit pixels (UP1, UP2, UP3, UP4) can have an "H" shape due to the protruding region (320p) of the pixel separator 320.

[0063] The pixel separator 320 may include an insulating layer (321a, 321b) surrounding the first to fourth unit pixels (UP1, UP2, UP3, UP4) and a filler layer 322 surrounding the insulating layer (321a, 321b).

[0064] The insulating layers (321a, 321b) may be padding layers surrounding the side surface of the first unit pixel (UP1). Each insulating layer (321a, 321b) may include at least one of silicon oxide, silicon oxynitride, silicon nitride, aluminum oxide, tantalum oxide, and hafnium oxide.

[0065] The insulating layers (321a, 321b) may include: a first insulating region (321a) having a first width or thickness (t1) along a direction X parallel to the substrate to cover three sides of the photoelectric conversion regions (PD1, PD2); and a second insulating region (321b) having a second thickness or width (t2) different from the first width (t1) along a direction X parallel to the substrate to cover the other side of the photoelectric conversion regions (PD1, PD2), on which two photoelectric conversion regions PD1 and PD2 within a unit pixel face each other and form a semiconductor bridging region (310br) therebetween to connect the first semiconductor region (310r1) and the second semiconductor region (310r2). The second width (t2) may be smaller than the first width (t1). Each of the first insulating region (321a) and the second insulating region (321b) may be a pad layer conformally extending along the side surface of the first unit pixel (UP1).

[0066] The first insulating region (321a) and the second insulating region (321b) may be regions separated in a plane by a specific distance relative to the padding layer. Therefore, the first insulating region (321a) may be integrally connected to the second insulating region (321b). The first insulating region (321a) may surround the first unit pixel (UP1) together with the second insulating region (321b). In some implementations, the first insulating region (321a) may comprise the same material as the second insulating region (321b).

[0067] The first insulating region (321a) may be located within the outer peripheral region (320s) of the pixel isolator 320, and the second insulating region (321b) may be located within the protruding region (320p) of the pixel isolator 320. That is, the first insulating region (321a) may be part of the padding layer located within the outer peripheral region (320s), and the second insulating region (321b) may be part of the padding layer located within the protruding region (320p). The second insulating region (321b) may be located between the first photoelectric conversion region (PD1) and the second photoelectric conversion region (PD2). The second insulating region (321b) may be located between the first semiconductor region (310r1) and the second semiconductor region (310r2).

[0068] A second insulating region (321b) may be located on the outer surface of the semiconductor bridging region (310br). In some implementations, the second insulating region (321b) may have portions extending from the outer surface of the semiconductor bridging region (310br) to the outer surface of an adjacent first semiconductor region (310r1) and / or portions extending from the outer surface of the semiconductor bridging region (310br) to the outer surface of an adjacent second semiconductor region (310r2). For example, the second insulating region (321b) may contact the side surface of the first semiconductor region (310r1) facing the second semiconductor region (310r2). In addition to the side surface of the first semiconductor region (310r1), the first insulating region (321a) may contact at least a portion of the remaining side surface of the first semiconductor region (310r1).

[0069] A filler layer (322) may surround the outer surface of an insulating layer (321a, 321b). The filler layer 322, together with the insulating layers (321a, 321b), may separate the first to fourth unit pixels (UP1, UP2, UP3, UP4) from each other. The filler layer (322) may include a conductive material (e.g., polysilicon). In some implementations, the filler layer (322) may be a layer for improving defects (e.g., electrostatic discharge (ESD) scratches) caused by photocharge generated on the exterior of the first to fourth unit pixels (UP1, UP2, UP3, UP4) when receiving a negative (-) voltage.

[0070] The filler layer (322) may be located within the outer peripheral region (320s). In some implementations, the filler layer 322 may have a portion extending from the outer peripheral region (320s) to the protruding region (320p). In this case, the second insulation region (321b) may surround the portion extending to the protruding region (320p) of the filler layer (322).

[0071] Figure 4A and Figure 4B This is a cross-sectional view illustrating an example of an image sensing device 300 based on some embodiments of the disclosed technology. Figure 4A This illustrates some implementations based on the disclosed technology. Figure 3 A cross-sectional view of the image sensing device 300 captured by line I-I'.

[0072] Reference Figure 4A The image sensing device 300 according to an exemplary embodiment may include a substrate layer 310 and an interconnect layer 340 located on the substrate layer 310.

[0073] The substrate layer 310 may have a first surface (310a) on which light is incident and a second surface (310b) facing or opposite to the first surface (310a). The substrate layer 310 may include between the first surface (310a) and the second surface (310b). Figure 3 The first semiconductor region (310r1), the second semiconductor region (310r2), the semiconductor bridging region (310br), and the pixel isolator 320 are described herein. The bottom surfaces of the first semiconductor region (310r1), the second semiconductor region (310r2), the semiconductor bridging region (310br), and the pixel isolator 320 may be coplanar to form a first surface (310a). The top surfaces of the first semiconductor region (310r1), the second semiconductor region (310r2), the semiconductor bridging region (310br), and the pixel isolator 320 may be coplanar to form a second surface (310b). In this specification, the term "coplanar" may mean that the surfaces of certain components are continuously connected to form the same surface.

[0074] Each of the first semiconductor region (310r1), the second semiconductor region (310r2), and the semiconductor bridging region (310br) may include silicon, germanium, silicon-germanium, group II-VI compound semiconductors, or group III-V compound semiconductors.

[0075] The first photoelectric conversion region (PD1) in the first semiconductor region (310r1) and the second photoelectric conversion region (PD2) in the second semiconductor region (310r2) may be spaced apart from each other in a first direction (X) between the first surface (310a) and the second surface (310b). In some implementations, the first semiconductor region (310r1), the second semiconductor region (310r2), and the semiconductor bridging region (310br) may include impurities of a first conductivity type, and the first photoelectric conversion region and the second photoelectric conversion region (PD1, PD2) may include impurities of a second conductivity type different from the first conductivity type. For example, the first conductivity type may be P-type, and the second conductivity type may be N-type.

[0076] Pixel spacer 320 may be disposed in a trench (OP) recessed from the second surface (310b) into the substrate layer 310. In some implementations, the trench (OP) may penetrate the substrate layer 310 toward the first surface (310a). In this case, the bottom surface of pixel spacer 320 may form part of the first surface (310a).

[0077] However, according to an embodiment, the trench (OP) can be recessed from the second surface (310b) into a predetermined depth in the substrate layer 310. In this case, the bottom surface of the pixel separator 320 can be located at a higher height than the first surface (310a). Figure 4AIn the diagram, the grooves (OP) are shown to have the same width, but according to some embodiments, the grooves (OP) may have a shape in which the width decreases in the direction from the second surface (310b) to the first surface (310a).

[0078] At the height of the substrate layer 310, multiple unit pixels (UP1, UP2, UP3, UP4) can be separated from each other by pixel separators 320.

[0079] The insulating layer 321 of the pixel separator 320 can be disposed on the sidewall of the trench (OP). For example... Figure 3 As described herein, insulating layer 321 may include a first insulating region (321a) and a second insulating region (321b). The first insulating region (321a) may cover at least a portion of the sidewall of the first side facing the first semiconductor region (310r1) (e.g., the outer peripheral region 320s of the pixel isolator 320) and may cover at least a portion of the sidewall of the first side facing the second semiconductor region (310r2) (e.g., the outer peripheral region 320s of the pixel isolator 320).

[0080] The second insulating region (321b) may cover at least a portion of the sidewall (e.g., the protruding region 320p of the pixel isolator 320) on the second side facing the first semiconductor region (310r1), and may also cover at least a portion of the sidewall (e.g., the protruding region 320p of the pixel isolator 320) on the second side facing the second semiconductor region (310r2).

[0081] To mitigate damage to adjacent semiconductor regions caused by the trench (OP) formation process, a plasma-based impurity doping process can be performed after the formation of the pixel isolator 320. In this case, the impurity doping concentration of the semiconductor region adjacent to the insulating layer 321 having a second width (t2) that is relatively smaller than the first width (t1) can be increased. Furthermore, the damage mitigation efficiency can be increased in response to subsequent voltage signals input to the semiconductor region in subsequent processes. Therefore, the disclosed technology provides an image sensing device 300 with improved autofocus performance in a 2PD pixel.

[0082] The filler layer 322 of the pixel spacer 320 may surround the insulating layer 321 within the trench (OP). The filler layer 322 may have a shape that fills the trench (OP) from the bottom surface of the trench (OP). The filler layer 322 may be located on the outer surface of the insulating layer 321.

[0083] In some implementations, the pixel separator 320 may further include a capping layer 323. The capping layer 323 may be disposed between the second surface (310b) of the substrate layer 310 and the filler layer 322 within the trench (OP). For example, the side surface of the capping layer 323 may be coplanar with the side surface of the filler layer 322. An insulating layer 321 may extend from the side surface of the filler layer 322 to the side surface of the capping layer 323.

[0084] The image sensing device 300 according to embodiments of the disclosed technology may further include a device separator 330. The device separator 330 may be a shallow trench isolation (STI) layer, and an active region within a unit pixel may be defined by the device separator 330. The device separator 330 may contact a second surface (310b) of the substrate layer 310. For example, the bottom surface of the device separator 330 may be located at a higher height than the bottom surface of the pixel separator 320. For example, the device separator 330 may include at least one of silicon oxide, silicon nitride, and silicon oxynitride.

[0085] Interconnect layer 340 may be disposed on the second surface (310b) of substrate layer 310 to support various circuit elements of each unit pixel.

[0086] The interconnect layer 340 may include at least one gate structure (342, 344, 345) disposed on the second surface (310b), a plug (not shown) connected to the gate structure (342, 344, 345), an interconnect line (not shown) connected to the plug (not shown), and an interlayer insulating layer 348.

[0087] The gate structure (342, 344, 345) may include a gate electrode 345 located on the second surface (310b), a dielectric layer 342 located between the gate electrode 345 and the substrate layer 310, and spacers 344 located on the side surface of the gate electrode 345. Figure 3 As shown, the positions of the gate structures (342, 344, 345) can be arranged differently within the interconnect layer 340.

[0088] The gate structures (342, 344, 345) can be used together with the source / drain regions of the substrate layer 310 to form a transistor, for example... Figure 2 The transistors include transfer transistors (TX1, TX2), reset transistors (RX), amplification transistors (SF), and selection transistors (SX).

[0089] The interlayer insulating layer 348 may be an insulating material layer covering the gate structure (342, 344, 345) on the second surface (310b).

[0090] Figure 4B This is a cross-sectional view illustrating an example of an image sensing device 300 based on some embodiments of the disclosed technology. Figure 4B This illustrates some implementations based on the disclosed technology. Figure 3 A cross-sectional view of the image sensing device 300 taken from line II-II'.

[0091] In some implementations, the image sensing device 300 may include an impurity region 315 in a region adjacent to the first surface (310a) of the substrate layer 310. For example, the impurity region 315 may be a region that contacts the first surface (310a) and is doped from the first surface (310a) to a predetermined depth. The impurity region 315 may include impurities of a first conductivity type. The impurity concentration of the impurity region 315 may be higher than the impurity concentration of the first semiconductor region (310r1) and the second semiconductor region (310r2). The impurity region 315 may be disposed in the semiconductor bridging region (310br). In the space between the first photoelectric conversion region (PD1) and the second photoelectric conversion region (PD2) that are adjacent to each other along the first direction (X), the impurity region 315 of the first protrusion region (320p1), the second protrusion region (320p2) of the semiconductor bridging region (310br) may be arranged side by side in the second direction (Y). The impurity region 315, together with the protruding region (320p) of the pixel isolator 320, can prevent or inhibit charge transfer between the first photoelectric conversion region (PD1) and the second photoelectric conversion region (PD2) of the second conductivity type. For example, the impurity region 315 may be doped with a relatively high concentration of impurities of the opposite conductivity type to that of the first photoelectric conversion region (PD1) and the second photoelectric conversion region (PD2), thereby preventing or inhibiting charge transfer between the photoelectric conversion regions.

[0092] Because a second insulating region (321b) with a second width (t2) smaller than the first insulating region (321a) is formed between the first semiconductor region (310r1) and the second semiconductor region (310r2), a relatively large amount of impurities can be doped in the subsequent process for forming the impurity region 315, thereby effectively improving the charge transfer between the first photoelectric conversion region (PD1) and the second photoelectric conversion region (PD2). Furthermore, the process difficulty for forming the impurity region 315 can be improved. Therefore, an image sensing device 300 with improved performance or yield can be provided.

[0093] Furthermore, because the insulating layer 321 within the protruding region (320p) is formed with a relatively small width, the dark current between the first semiconductor region (310r1) and the second semiconductor region (310r2) can be effectively improved. For example, when a negative (-) voltage is applied to the filler layer 322 in the future to improve the dark current on the surfaces of the first and second semiconductor regions (310r1, 310r2), a relatively high voltage is applied to the semiconductor region adjacent to the protruding region (320p) with its small width in the insulating layer 321, thereby effectively improving the dark current. Therefore, an image sensing device with improved autofocus performance can be provided.

[0094] The image sensing device 300 according to an exemplary embodiment may further include an anti-reflective layer (not shown) on a first surface (310a) of a substrate layer 310, a grid (not shown) on the anti-reflective layer, a color filter layer (not shown) covering the grid, and a microlens layer (not shown) on the color filter layer.

[0095] An anti-reflective layer may be disposed between the first surface (310a) of the substrate layer 310 and the color filter to prevent light reflection, so that incident light can smoothly reach the photoelectric conversion regions (PD1, PD2). A grid may be configured to overlap perpendicularly with the pixel isolator 320. The grid guides incident light onto the photoelectric conversion regions (PD1, PD2). The grid may include a conductive material. The color filter layer includes color filters covering each individual pixel, and may include color filters that transmit green, red, and blue light. The aforementioned color filters filter the wavelengths of light received by the photoelectric conversion regions (PD1, PD2) to determine the type of the individual pixel. The color filter may have a portion overlapping the first photoelectric conversion region (PD1) in a plane and another portion overlapping the second photoelectric conversion region (PD2) in a plane. That is, one color filter may correspond to two photoelectric conversion regions (PD1, PD2) within one individual pixel.

[0096] A microlens layer may be disposed on a color filter layer. The microlens layer may include an array of microlenses, each covering a unit pixel. Each microlens may have a convex shape and a predetermined radius of curvature. The microlens may collect incident light to transmit it into the respective unit pixel to reach a first photoelectric conversion region (PD1) and a second photoelectric conversion region (PD2). The microlens may have a portion overlapping the first photoelectric conversion region (PD1) in a plane and another portion overlapping the second photoelectric conversion region (PD2) in a plane. That is, one microlens may correspond to two photoelectric conversion regions (PD1, PD2) within a unit pixel. For example, the microlens may include a light-transmitting resin.

[0097] In the following description, an image sensing apparatus according to the above-described embodiments and other embodiments of the disclosed technology will be described. The following description will focus on another embodiment of pixel isolation, but it will be understood that the plurality of unit pixels are substantially the same as those described above.

[0098] Figure 5 This is a plan view illustrating an example of an image sensing device 300A based on some embodiments of the disclosed technology.

[0099] Reference Figure 5 ,and Figure 4A and Figure 4B Unlike the second insulating region (321b) of the image sensing device 300, the image sensing device 300A may include a second insulating region (321b') disposed only on the side surface of the semiconductor bridging region (310br). In this case, it has a second width (t2) (see...). Figure 3 The second insulating region (321b') may not have portions extending onto the side surfaces of the first semiconductor region (310r1) and the second semiconductor region (310r2). For example, it may have a first width (t1) (see...). Figure 3 A portion of the first insulating region (321a') may extend between the first semiconductor region (310r1) and the second semiconductor region (310r2).

[0100] Because a second insulating region (321b') with a relatively small width is arranged on the semiconductor bridging region (310br), an image sensing device 300A can be provided with reduced process difficulty or increased doping concentration of the impurity region 315 compared to the same process time.

[0101] Figure 6 This is a plan view illustrating an example of an image sensing device 300B based on some embodiments of the disclosed technology.

[0102] Reference Figure 6 The image sensing device 300B may include an insulating layer (321”) having regions of different widths on adjacent side surfaces depending on the type of multiple unit pixels (UP1, UP2, UP3, UP4).

[0103] Multiple unit pixels (UP1, UP2, UP3, UP4) may include a first unit pixel (UP1), a second unit pixel (UP2), a third unit pixel (UP3), and a fourth unit pixel (UP4). For example, the first unit pixel (UP1) may be a green pixel, the second unit pixel (UP2) may be a red pixel, and the third unit pixel (UP3) may be a blue pixel.

[0104] The insulating layer (321) may include a first insulating region (321a”), a second insulating region (321b_1), a third insulating region (321b_2) and a fourth insulating region (321b_3).

[0105] The first insulating region (321a) may surround multiple unit pixels (UP1, UP2, UP3, UP4) and may distinguish the multiple unit pixels (UP1, UP2, UP3, UP4) from one another. For example, the first insulating region (321a) may be disposed between adjacent first unit pixels (UP1) and second unit pixels (UP2). The first insulating region (321a) may have a first width (t1').

[0106] The second insulating region (321b_1) may be disposed between the first semiconductor region (310r1) and the second semiconductor region (310r2) of the first unit pixel (UP1). In addition to having a second width (t2'), the second insulating region (321b_1) may have the same characteristics as... Figure 3 The second insulating region (321b) described herein has the same or similar characteristics. The second width (t2') may be a width different from the first width (t1').

[0107] The third insulating region (321b_2) may be disposed between the first semiconductor region (310r1) of the second unit pixel (UP2) and the second semiconductor region (310r2) of the second unit pixel (UP2). In addition to having a third width (t3'), the third insulating region (321b_2) may have the same... Figure 3 The second insulating region (321b) described herein has the same or similar characteristics. The third width (t3') may be a width different from the first width (t1') and the second width (t2').

[0108] A fourth insulating region (321b_3) may be disposed between the first semiconductor region (310r1) and the second semiconductor region (310r2) of the third unit pixel (UP3). In addition to having a fourth width (t4'), the fourth insulating region (321b_3) may have the same... Figure 3 The second insulating region (321b) described herein has the same or similar characteristics. The fourth width (t4') may differ from each of the first to third widths (t1', t2', t3').

[0109] The fourth width (t4') can be greater than each of the second width (t2') and the third width (t3'). The third width (t3') can be greater than the second width (t2').

[0110] The sensitivity of a single pixel to light can vary depending on its type. For example, a green pixel may exhibit higher sensitivity than a red pixel, and a red pixel may exhibit higher sensitivity than a blue pixel. In this case, to improve uniformity, the sensitivity of the relatively high-sensitivity green pixels is reduced, while the sensitivity of the relatively low-sensitivity blue pixels is increased. This adjustment improves the uniformity of sensitivity across different unit pixels of different colors, thereby reducing noise and improving the overall performance of the image sensing device.

[0111] In some implementations, the width of the insulating region of the insulating layer (321") can be adjusted differently for each type of unit pixel to improve the uniformity of sensitivity characteristics. As the width of the insulating layer (321") adjacent to the unit pixel increases, the sensitivity characteristics of the unit pixel can be improved by reducing adjacent noise. Therefore, the uniformity of sensitivity characteristics can be improved by adjusting the width of the insulating layer adjacent to the blue pixel, which has relatively low sensitivity characteristics, to a higher value. For example, the fourth width (t4') of the third unit pixel (UP3), which is a blue pixel, can be greater than the third width (t3') of the second unit pixel (UP2), which is a red pixel, and the third width (t3') of the second unit pixel (UP2), which is a red pixel, can be greater than the second width (t2') of the first unit pixel (UP1), which is a green pixel.

[0112] The first width (t1') can be greater than each of the second to fourth widths (t2', t3', t4').

[0113] In this case, the disclosed technology can provide an image sensing device 300B, wherein the impurity region 315 of the 2PD pixel structure (see Figure 4B The doping characteristics of the material are improved, and the performance is also improved based on the difference in sensitivity.

[0114] Figure 7 This is a plan view illustrating an example of an image sensing device 300C based on some embodiments of the disclosed technology.

[0115] Reference Figure 7 The image sensing device 300C may include a first insulating region (321a_1, 321a_2) with a multilayer structure of different materials.

[0116] The first insulating region (321a_1, 321a_2) may include a first layer (321a_1) integrally connected to and extending from the second insulating region (321b”’) and a second layer (321a_2) on the first layer (321a_1). Each of the first layer (321a_1) and the second layer (321a_2) may include at least one of silicon oxide, silicon nitride, silicon oxynitride, aluminum oxide, tantalum oxide, and hafnium oxide. The first layer (321a_1) may have a second width (t2) equal to that of the second insulating region (321b”’) (see See Figure 3 The width of the first layer (321a_1) and the sum of the widths of the second layer (321a_2) can be the first width (t1) (see Figure 3 The first layer (321a_1) may be disposed in the outer peripheral region (320s) of the pixel separator 320. The first layer (321a_1) may include the same material as the second insulating region (321b”'). In some implementations, the first layer (321a_1) may be formed in the same process as the process for forming the second insulating region (321b”'). The second layer (321a_2) may include a different material than the first layer (321a_1). However, according to an embodiment, the second layer (321a_2) may include the same material as the first layer (321a_1). The second layer (321a_2) may be formed by performing a process separate from the process for forming the first layer (321a_1) and the second insulating region (321b”').

[0117] Figures 8A to 8D This is a cross-sectional view illustrating an example of a method for manufacturing an image sensing device based on some embodiments of the disclosed technology. Figures 8A to 8D It shows along Figure 3 A cross-sectional view of an example image sensing device captured by line I-I'.

[0118] Reference Figure 8A A trench (OP) can be formed to penetrate the substrate layer 310 that forms the first photoelectric conversion region (PD1) and the second photoelectric conversion region (PD2).

[0119] The trench (OP) can be formed by performing an anisotropic etching process on the second surface (310b) of the substrate layer 310. This can be targeted at the formation of... Figure 3 The area of ​​the pixel isolator 320 is formed into a trench (OP) using a single etching process with a mask. Therefore, the area corresponding to the outer peripheral area (320s) and the protrusion area (320p) of the pixel isolator 320 can be formed as an opening, exposing the side surface of the adjacent substrate layer 310.

[0120] Reference Figure 8BAn insulating layer 321 can be formed on the side surface of the exposed substrate layer 310 by performing a deposition process using an insulating material with a first mask (M1). The insulating layer 321 may have a constant width in the peripheral region (320s) and the protruding region (320p) and may cover the exposed side surface of the substrate layer 310.

[0121] Reference Figure 8C Since a deposition process using the same material as the insulating material is performed using a second mask (M2) covering the protruding region (320p), the width of the insulating layer 321 in the outer peripheral region (320s) can be increased. Therefore, a first insulating region (321a) having a first width (t1) in the outer peripheral region (320s) and a second insulating region (321b) having a second width (t2) smaller than the first width (t1) in the protruding region (320p) can be formed.

[0122] As the planar shape of the second mask (M2) changes, it can provide a basis for... Figure 5 or Figure 6 Some implementations of the image sensing device.

[0123] exist Figure 8B deposition process and Figure 8C In the deposition process, different insulating materials can be used to provide [the desired effect]. Figure 7 The image sensing device according to the embodiment.

[0124] However, according to the implementation method, with Figure 8B and Figure 8C Unlike other methods, the mask shape can be changed so that the first insulating region (321a) of the outer peripheral region (320s) and the second insulating region (321b) of the protruding region (320p) can be formed by separate deposition processes.

[0125] Reference Figure 8D The filler layer 322 can be formed by performing a deposition process using a semiconductor material (e.g., polysilicon). By performing a separate etching process or controlling the amount of deposited material, the filler layer 322 can be formed to have a height lower than that of the insulating layer 321.

[0126] Subsequently, a capping layer 323 can be formed (see...) Figure 4A An interconnect layer 340 can be formed on the second surface (310b) (see...) Figure 4A ), and can be achieved by doping the first surface (310a) with an impurity of a first conductivity type (e.g., p-type) in the semiconductor bridging region (310br) (see Figure 4B Impurity region 315 is formed in ) (see Figure 4BFor example, doping can be performed by plasma doping (PLAD). In this case, performance or yield can be improved (e.g., by increasing the doping concentration of the impurity region 315 or shortening the process time) because a second insulating region (321b) with a relatively thin width is formed near the semiconductor bridging region (310br) compared to the first insulating region (321a) of the peripheral region (320s).

[0127] As is evident from the above description, the image sensing device according to the disclosed technology can enable the insulating layer surrounding a unit pixel to have different widths depending on the position of the insulating layer, thereby reducing the process difficulty of forming impurity regions and enabling the image sensing device to have higher yield.

[0128] By relatively increasing the doping concentration in the impurity region, the image sensing device according to the disclosed technology implementation has higher autofocus performance.

[0129] An image sensing device according to an embodiment of the disclosed technology includes a region in which the width of an insulating layer varies depending on the type of unit pixel, so that the image sensing device has higher sensitivity uniformity.

[0130] The implementation of the disclosed technology can provide various effects that can be directly or indirectly recognized through the aforementioned patent documents.

[0131] Those skilled in the art will understand that the disclosed technology can be implemented in specific ways other than those described herein. Furthermore, claims not expressly presented in the appended claims may be presented as a combination of embodiments, or may be included as new claims through subsequent amendments after filing.

[0132] Although several exemplary embodiments have been described, it should be understood that modifications and enhancements to the disclosed embodiments and other embodiments can be conceived based on the description and / or illustrations in this patent document.

[0133] Cross-reference and priority claims of related applications

[0134] This patent document claims priority and benefit to Korean Patent Application No. 10-2025-0047317, filed on April 11, 2025, the disclosure of which is incorporated herein by reference in its entirety as part of the disclosure of this patent document.

Claims

1. An image sensing device, the image sensing device comprising: A substrate, the substrate including a first surface for receiving incident light and a second surface opposite to the first surface; A unit pixel, supported by the substrate, includes a first photoelectric conversion region and a second photoelectric conversion region, wherein the first photoelectric conversion region generates an electrical signal in response to the incident light, and the second photoelectric conversion region is spaced apart from the first photoelectric conversion region and generates an electrical signal in response to the incident light. as well as A pixel spacer disposed in a trench recessed from the second surface into the substrate, the pixel spacer comprising: A first insulating region having a first width along a direction parallel to the substrate; and A second insulating region having a width different from the first width. The second insulating region is disposed between the first photoelectric conversion region and the second photoelectric conversion region.

2. The image sensing device according to claim 1, wherein, The second width is smaller than the first width.

3. The image sensing device according to claim 1, wherein, The first insulating region is integrally connected to the second insulating region.

4. The image sensing device according to claim 3, wherein, The first insulating region and the second insulating region have the same height in a direction perpendicular to the first surface; and The first insulating region is formed to surround the unit pixel together with the second insulating region.

5. The image sensing device according to claim 1, wherein, The pixel spacers also include: A filler layer surrounds the outer surface of an insulating layer within the trench, the insulating layer comprising a first insulating region and a second insulating region.

6. The image sensing device according to claim 5, wherein, The insulating layer comprises at least one of silicon oxide, silicon nitride, silicon oxynitride, aluminum oxide, tantalum oxide, or hafnium oxide; and The filler layer comprises a semiconductor material.

7. The image sensing device according to claim 5, wherein, The pixel separator further includes a capping layer disposed between the second surface of the substrate and the filler layer within the trench; and The insulating layer extends from the side surface of the filler layer to the side surface of the capping layer.

8. The image sensing device according to claim 1, wherein, The unit pixel includes a first semiconductor region, a second semiconductor region, and a semiconductor bridging region. The first semiconductor region includes a first photoelectric conversion region, the second semiconductor region includes a second photoelectric conversion region, and the semiconductor bridging region connects the first semiconductor region and the second semiconductor region to each other. The second insulating region is disposed on the outer surface of the semiconductor bridging region; and The second width is smaller than the first width.

9. The image sensing device according to claim 8, wherein, The first photoelectric conversion region is spaced apart from the second photoelectric conversion region in a first direction; The first semiconductor region extends parallel to the second semiconductor region in a second direction perpendicular to the first direction; and The second insulating region includes a portion extending from the outer surface of the semiconductor bridging region to the outer surface of the first semiconductor region and a portion extending from the outer surface of the semiconductor bridging region to the outer surface of the second semiconductor region.

10. The image sensing device according to claim 1, further comprising: Adjacent unit pixels adjacent to the unit pixel, The first insulating region is disposed between the unit pixel and the adjacent unit pixel. Wherein, the second insulating region is disposed between the first photoelectric conversion region of the unit pixel and the second photoelectric conversion region of the unit pixel, and The pixel separator further includes: A third insulating region is disposed between the first photoelectric conversion region and the second photoelectric conversion region of the adjacent unit pixel, and the third insulating region has a third width that is different from the first width and the second width.

11. The image sensing device according to claim 10, wherein, The unit pixel is a red pixel that detects light within the red wavelength band; The adjacent unit pixel is a green pixel that detects light within the green wavelength band; The first width is greater than the second width; and The second width is greater than the third width.

12. The image sensing device according to claim 10, wherein, The unit pixel is a blue pixel that detects light within the blue wavelength band; The adjacent unit pixel is a red pixel that detects light within the red wavelength band; The first width is greater than the second width; and The second width is greater than the third width.

13. The image sensing device according to claim 1, wherein, The first insulating region is a multi-layered structure comprising different materials; and The second insulating region is a single-layer structure.

14. An image sensing device, the image sensing device comprising: A unit pixel includes a first semiconductor region, a second semiconductor region, and a semiconductor bridging region. The first semiconductor region includes a first photoelectric conversion region for detecting light. The second semiconductor region includes a second photoelectric conversion region for detecting light and is spaced apart from the first semiconductor region in a first direction. The semiconductor bridging region connects the first semiconductor region and the second semiconductor region. as well as A pixel isolator is formed around the unit pixel and configured to include a first insulating region and a second insulating region, the first insulating region having a first width and disposed along a side surface of the unit pixel, and the second insulating region having a second width less than the first width and disposed along another side surface of the unit pixel.

15. The image sensing device according to claim 14, wherein, The pixel spacers include: The outer perimeter area; and A protruding region extending from the outer peripheral region to the semiconductor bridging region in a second direction perpendicular to the first direction. Wherein, the first insulating region is disposed in the outer peripheral region, and The second insulating region is disposed in the protruding region.

16. The image sensing device according to claim 15, wherein, The pixel spacers also include: A filler layer surrounds an insulating layer comprising the first insulating region and the second insulating region. The filler layer includes a portion extending from the outer peripheral region to the protruding region.

17. The image sensing device according to claim 14, wherein, The first semiconductor region is connected to the semiconductor bridging region and extends in a second direction perpendicular to the first direction; The second semiconductor region is connected to the semiconductor bridging region and extends in the second direction; The second insulating region contacts the side surface of the first semiconductor region facing the second semiconductor region or opposite to the second semiconductor region; and The first insulating region contacts at least a portion of the remaining side surface of the first semiconductor region.

18. An image sensing device, the image sensing device comprising: A substrate, the substrate including a first surface for receiving incident light and a second surface opposite to the first surface; A unit pixel, supported by the substrate, includes a first semiconductor region, a second semiconductor region, and a semiconductor bridging region. The first semiconductor region includes a first photoelectric conversion region for detecting light, and the second semiconductor region includes a second photoelectric conversion region for detecting light. The second semiconductor region is spaced apart from the first semiconductor region in a first direction, and the semiconductor bridging region is disposed between the first semiconductor region and the second semiconductor region. A pixel separator disposed in a trench recessed from the second surface into the substrate, and comprising an insulating layer surrounding the unit pixel and a filler layer surrounding the insulating layer; as well as An interconnect layer is disposed on the second surface of the substrate. The insulating layer includes: A first insulating region, the first insulating region having a first thickness in the outer peripheral region; and The second insulating region has a second thickness in a protruding region extending from the outer peripheral region into the semiconductor bridging region in a second direction perpendicular to the first direction.

19. The image sensing device according to claim 18, wherein, The first thickness is greater than the second thickness.

20. The image sensing device according to claim 18, wherein, The first insulating region and the second insulating region comprise the same material; and Each of the first insulating region and the second insulating region extends conformally along the side surface of the unit pixel.

Images