Integrated circuit device and manufacturing method thereof

Abstract

Some embodiments relate to an integrated circuit (IC) device including a substrate including a plurality of first photodetector groups associated with a plurality of color pixels, respectively, and a plurality of second photodetector groups associated with a plurality of phase detection pixels, respectively, and a method of manufacturing the same. Each of the first photodetector group and the second photodetector group includes one or more photodetectors. The device also includes a grid structure on the substrate, a color filter on the substrate, and a crosstalk reduction structure. The lattice structure includes light shields, each configured to redirect light away from a respective one of the second photodetector groups. Each color filter vertically spans the lattice structure at a respective one of the first photodetector groups. The crosstalk reduction structure is transverse to the color filter and limits an amount of light redirected by the light shield of each phase detection pixel to the first photodetector group of an adjacent one of the color pixels.

Description

Technical Field

[0001] Embodiments of the present application relate to integrated circuit devices and methods for manufacturing the same. Background Art

[0002] Some integrated circuit (IC) manufacturers integrate aspects of phase detection autofocus (PDAF) technology in complementary metal oxide semiconductor (CMOS) image sensor (CIS) devices. In such devices, the speeds associated with PDAF technology can be higher than the rates associated with other autofocus technologies because the device can provide the phase detection data required for the autofocus function on a continuous basis with little delay while capturing image data. Summary of the invention

[0003] According to one aspect of an embodiment of the present application, an integrated circuit device is provided, comprising: a substrate, comprising a plurality of first photodetector groups respectively associated with a plurality of color pixels and a plurality of second photodetector groups respectively associated with a plurality of phase detection pixels, wherein each of the first photodetector groups and the second photodetector groups comprises one or more photodetectors; a grid structure, located on the substrate, wherein the grid structure comprises a plurality of light shields, each light shield being configured to redirect light away from a corresponding one of the second photodetector groups; a plurality of color filters, located on the substrate, each color filter vertically spanning the grid structure at a corresponding one of the first photodetector groups; and a crosstalk reduction structure, transverse to the color filters, and limiting the amount of light of the first photodetector group redirected by the light shield of each phase detection pixel to an adjacent one of the color pixels.

[0004] According to another aspect of an embodiment of the present application, an integrated circuit device is provided, comprising: a substrate, comprising a first at least one photodetector and a second at least one photodetector adjacent to the first at least one photodetector, the first at least one photodetector being associated with a phase detection pixel, and the second at least one photodetector being associated with a color pixel; a grid structure located above the substrate, the grid structure comprising: a light shield located above a first portion of the first at least one photodetector; a first opening located above a second portion of the first at least one photodetector, the second portion being different from the first portion; and a second opening located above the second at least one photodetector; a color filter located above the second at least one photodetector in the second opening; and a crosstalk reduction structure, lateral to the color filter and configured to limit light redirected by the light shield to the second at least one photodetector.

[0005] According to another aspect of an embodiment of the present application, a method for manufacturing an integrated circuit device is provided, comprising: forming a plurality of photodetector groups in a substrate, each photodetector group comprising one or more photodetectors, each photodetector group being associated with one of one or more phase detection pixels in a plurality of color pixels; depositing a metal layer on the substrate; etching the metal layer to form a grid structure comprising a plurality of openings, each opening being arranged on one of the photodetector groups, and further comprising a plurality of light shields, each light shield being configured to redirect light away from a corresponding photodetector group associated with one of the phase detection pixels; forming a plurality of color filters above the grid structure, each color filter being arranged on a corresponding photodetector group associated with one of the color pixels; and forming a crosstalk reduction structure, the crosstalk reduction structure being transverse to the plurality of color filters and limiting the amount of light redirected by the light shield of each phase detection pixel to the photodetector group of an adjacent color pixel. BRIEF DESCRIPTION OF THE DRAWINGS

[0006] Various aspects of the present disclosure can be best understood from the following detailed description when read in conjunction with the accompanying drawings. It should be emphasized that, in accordance with standard practice in the industry, the various components are not drawn to scale and are only used for illustrative purposes. In fact, the size of the various components may be arbitrarily increased or reduced for clarity of discussion.

[0007] Figure 1A and Figure 1B Schematic cross-sectional views and plan views of some embodiments of an integrated circuit (IC) device employing a crosstalk reduction structure for a semi-shielded PDAF according to the present disclosure are respectively shown.

[0008] FIG. 2A to FIG. 2F , Figures 3 to 8 as well as Fig.9A and Fig. 9B Cross-sectional views of some embodiments of IC devices employing a crosstalk reduction structure for semi-shielded PDAF according to the present disclosure are shown.

[0009] FIG. 10A to FIG. 10P The following is shown in the various manufacturing stages according to the present disclosure. Figure 2A Cross-sectional views of some embodiments of IC devices for crosstalk reduction structures of semi-shielded PDAF are shown.

[0010] Fig.11 Block diagrams of some embodiments of methods of forming crosstalk reduction structures and IC devices employing semi-shielded PDAF according to the present disclosure are shown. DETAILED DESCRIPTION

[0011] The following disclosure provides many different embodiments or examples for realizing different features of the present disclosure. Specific embodiments or examples of components and arrangements are described below to simplify the present disclosure. Of course, these are only examples and are not intended to be limiting. For example, in the following description, forming a first component above or on a second component may include an embodiment in which the first component and the second component are directly contacted, and may also include an embodiment in which an additional component may be formed between the first component and the second component so that the first component and the second component may not be in direct contact. In addition, the present disclosure may repeat reference numbers and / or letters in various examples. This repetition is for the purpose of simplicity and clarity, and does not itself indicate the relationship between the various embodiments and / or configurations discussed.

[0012] Additionally, for ease of description, spacing relation terms such as "below," "beneath," "lower," "above," "upper," etc. may be used herein to describe the relationship of one element or component to another element or component as shown in the figures. The spacing relation terms are intended to encompass different orientations of the device in use or in the process of operation in addition to the orientation shown in the figures. The device may be otherwise oriented (rotated 90 degrees or at other orientations) and the spacing relation descriptors used herein may likewise be interpreted accordingly.

[0013] In some cases, phase detection autofocus (PDAF) functionality can be incorporated into a complementary metal oxide semiconductor (CMOS) image sensor (CIS) integrated circuit (IC) device via a half-shielded phase detection pixel design. In such a design, some pixel locations of an image pixel array are occupied by dedicated phase detection pixels that include a "half-shield" disposed over a portion (e.g., the left half or the right half) of the associated pixel, thereby substantially blocking half of the light from one or more photodetectors associated with the pixel. Processing data from the phase detection pixels can produce an indication (e.g., magnitude and direction) by which a relative distance between an external lens (e.g., a camera lens) and the CIS IC device can be changed to bring an object into focus on the CIS IC device. However, in some designs, some of the light encountering the half-shield may be improperly directed to adjacent image pixels, such as by total internal reflection (TIR) ​​at a microlens located above a photodetector corresponding to the image pixel, thereby potentially increasing the amount of light detected by the image pixel beyond the amount of light actually associated with that pixel.

[0014] To address these issues, the present disclosure provides some embodiments of an IC device that employs a crosstalk reduction structure that may be located in a layer of the IC device that includes a color filter for image pixels and a grid structure that may include a semi-shielded grid structure for phase detection pixels. In some embodiments, the crosstalk reduction structure may include, for example, additional color filters, an anti-reflective coating (ARC), and / or width variations of individual segments of the grid structure. Use of the crosstalk reduction structure may reduce the amount of light redirected to adjacent image pixels by the semi-shielded grid structure. Thus, potential problems caused by such crosstalk, such as unwanted flash associated with color pixels, sensitivity variations between color pixels, sensitivity variations between color pixels and phase detection pixels, etc., may be mitigated.

[0015] Figure 1A and Figure 1B Schematic cross-sectional views and plan views of some embodiments of an IC device 100 (eg, an IC imaging device) using a crosstalk reduction structure for semi-shielded PDAF according to the present disclosure are shown, respectively. More specifically, Figure 1A is a schematic cross-sectional view of an IC device 100 in which the components of each layer of the IC device 100 associated with each pixel are strictly stacked vertically. However, in other embodiments, these same components may be tilted laterally from one layer to another. For example, in some embodiments, the chief ray angle associated with each pixel can vary based on the position of the pixel within the pixel array in the IC device 100. More specifically, pixels at or near the center of the array may have a chief ray angle of approximately zero degrees, resulting in the components of the pixel being stacked substantially vertically. In contrast, pixels near the edges or corners of the array may have significant chief ray angles, which require skewing the components of these pixels toward the center of the array. In some examples, this component skewing may exacerbate potential crosstalk between phase detection pixels and imaging pixels. FIG. 2A to FIG. 2F , Figures 3 to 8 as well as Fig.9A and Fig. 9B The various embodiments shown depict this deflection.

[0016] like Figure 1A As shown, the substrate 102 may include a plurality of photodetectors (PDs) (eg, photodiodes, etc.) including a PD region 104 formed (eg, doped or implanted) in the substrate 102. In some embodiments, as shown in FIG. Figure 1A As shown, each pixel includes two PD regions 104. However, in other embodiments, one or more PD regions 104 may be used in each pixel.

[0017] Adjacent to the substrate 102 may be a circuit dielectric layer 112, which includes sensor circuitry 114 (e.g., including various conductive structures, such as copper structures) that couples with the photodetectors of the substrate 102 (e.g., transfers charge generated by photons striking the PD region 104 to reset the associated photodetectors, etc.). The circuit dielectric layer 112 may include one or more dielectric materials, including but not limited to silicon oxide (SiO x ) (e.g., silicon oxide (SiO2)), silicon nitride (SiN), silicon carbide (SiC), carbon-doped silicon dioxide, silicon oxynitride, borosilicate glass (BSG), phosphosilicate glass (PSG), borophosphosilicate (BPSG), fluorosilicate glass (FSG), undoped silicate glass (USG), porous dielectric materials, etc. In some embodiments, additional layers may be disposed below the circuit dielectric layer 112, but these layers are not discussed further herein to simplify the following discussion.

[0018] The sensor dielectric layer 106 can be disposed on the substrate 102. In some embodiments, the sensor dielectric layer 106 can include one or more dielectric materials, such as those listed above in conjunction with the circuit dielectric layer 112. In addition, an enhanced color filter / metal grid (CF / MG) layer 108 can be disposed over the sensor dielectric layer 106. As described in more detail below, the enhanced CF / MG layer 108 includes a crosstalk reduction structure 109 (e.g., an additional color filter) that limits or reduces crosstalk between a semi-shielded phase detection (HSPD) pixel 120 and an adjacent color pixel 122.

[0019] In some embodiments, the enhanced CF / MG layer 108 may include a grid structure (eg, a metal grid (MG)) 132 and a color filter (CF) 134 for each color pixel 122 . Figure 1B Shows Figure 1A Schematic plan view of the grid structure 132, which shows the grid properties. As shown, Figure 1B The ratio is approximately Figure 1A The grid structure 132 includes a plurality of grid segments 133 that form a plurality of openings 131 through which light can pass before encountering the PD regions 104 associated with the color pixels 122 and the semi-shielded phase detection (HSPD) pixels 120. In addition, for each HSPD pixel 120, the grid structure 132 may include a half-shield (HS) 130 for phase detection purposes that covers approximately half of the associated HSPD pixel. In some embodiments, the grid structure 132 may include a metal, a metal alloy, or another material that substantially reflects light.

[0020] Back to Figure 1A, in some embodiments, the CF 134 can be disposed on the grid structure 132 and the sensor dielectric layer 106. In some embodiments, each CF 134 can be disposed over a corresponding color pixel 122, and possibly over a corresponding HSPD pixel 120, as described in detail below. Furthermore, in some embodiments, each CF 134 extends through or vertically spans the grid structure 132, and can allow light associated with one of a plurality of colors (e.g., red, green, or blue) to pass therethrough to the PD region 104 associated with the CF 134. As described above, the enhanced CF / MG layer 108 can include a crosstalk reduction structure 109 that is flush with or lateral to the CF 134 of the enhanced CF / MG layer 108. Figure 1A and Figure 1B In particular, a crosstalk reduction structure 109 is depicted as an additional color filter (eg, as described below with reference to Figure 4 However, as described below, other crosstalk reducing structures (e.g., anti-reflection coating on at least a portion of the grid structure, variations in the width of the grid structure segments, etc.) are also possible.

[0021] like Figure 1B As shown, the color pixels 122 can be arranged in a particular pattern (e.g., within a two-dimensional array) to facilitate accurate color imaging. In addition, the HSPD pixels 120 can be distributed between the color pixels 122 in a periodic manner. In some embodiments, the HSPD pixels 120 can be arranged in pairs. For example, a first HSPD pixel 120 can correspond to a HS130 that covers a first (e.g., left) PD region 104 of two PD regions 104 associated with the first HSPD pixel 120. In addition, the second HSPD pixel 120 can correspond to a HS130 that covers a second (e.g., right) PD region 104 of two PD regions 104 associated with the second HSPD pixel 120. However, in addition to Figure 1B In addition to the arrangement shown, other arrangements of color pixels 122 and HSPD pixels 120 are possible.

[0022] Back to Figure 1A , a lens layer 110 (e.g., including a plurality of lenses, such as microlenses) may be disposed on the enhanced CF / MG layer 108. In some embodiments, each lens of the lens layer 110 may be associated with a corresponding pixel (e.g., a color pixel 122 or a HSPD pixel 120), and thus be located over a pair of PD regions 104 associated with the pixel. Although in the embodiments described in more detail below, each lens of the lens layer 110 is presented as a microlens, other types of lenses (e.g., Fresnel-type lenses) may be employed in other embodiments, but are not specifically discussed herein.

[0023] FIG. 2A to FIG. 2F , Figures 3 to 8 as well as Fig.9A and Fig. 9B 1 shows a cross-sectional view of some embodiments of IC devices (e.g., IC device 100) that employ crosstalk reduction structures for semi-shielded PDAF according to the present disclosure. In each of these embodiments, substrate 102 includes a plurality of photodetectors (PDs) (e.g., photodiodes, etc.) that include PD regions 104 formed (e.g., doped or implanted) in substrate 102. In some embodiments (e.g., in Figure 2A , Figure 2B , Figure 3-Figure 8 , Fig.9A and Fig. 9B ), PD regions 104 and their associated photodetectors are organized in pairs, with each pair being associated with a color pixel 122 or a HSPD pixel 120. In other embodiments (e.g., Figure 2C and Figure 2D ), each color pixel 122 includes a single PD region 104, while each HSPD pixel 120 includes two PD regions 104. In other embodiments (e.g., Figure 2E and Figure 2F ), each color pixel 122 and HSPD pixel 120 includes a single PD region 104.

[0024] In some embodiments, a high dielectric constant (high-K) dielectric film 204 is disposed over the substrate 102. Examples of the high-K dielectric film 204 may include, but are not limited to, aluminum oxide (Al2O3), hafnium oxide (HfO2), zirconium dioxide (ZrO2), titanium dioxide (TiO2), etc. In addition, the sensor dielectric layer 106 may be disposed on the high-K dielectric film 204. As described above, the sensor dielectric layer 106 may include, but is not limited to, silicon dioxide (SiO2), another silicon oxide (SiO x ) or another dielectric material.

[0025] In addition, between at least some adjacent PD regions 104 (e.g., between adjacent color pixels 122 or between a color pixel 122 and a HSPD pixel 120), a shallow trench isolation (STI) structure 202 may extend to the lower surface of the substrate 102. In some embodiments, the STI structure 202 may include a dielectric material, such as SiO2, SiO x In addition, between each pair of adjacent PD regions 104, a backside deep trench isolation (BDTI) structure 210 may extend to the upper surface of the substrate 102. Figure 2AAs shown, the BDTI structure 210 may include multiple layers of material. In some embodiments, the BDTI structure 210 may include a core 214, which includes a light reflective material, which may include one or more metals or oxides. Surrounding the core 214 may be a dielectric film 216. In some embodiments, the dielectric film 216 may include, but is not limited to, oxides (e.g., SiO2, SiO x In turn, the capping dielectric film 216 may be a high-K dielectric film 218, which may include the same or similar materials as the high-K dielectric film 204, as described above.

[0026] On the sensor dielectric layer 106, a grid structure including grid segments 133 is arranged, as described above in conjunction with Figure 1A and Figure 1B In the plan view of the IC device 100, the grid segments 133 provide openings for each color pixel 122 and HSPD pixel 120. The grid structure may also include half shields 130, each half shield 130 covering one PD region 104 of each photodetector pair of the corresponding HSPD pixel 120. In addition, on the grid structure and the sensor dielectric layer 106, for each color pixel 122, a CF 134 is provided to cover the photodetector pair associated with the color pixel 122. The CF 134 and the grid structure 132 (e.g., Figure 1A and Figure 1B The grid structure 132 of the CF / MG layer 108 may be included together in the enhanced CF / MG layer 108. In some embodiments, each CF 134 may be a dielectric material that filters light of one or more wavelength bands to allow a specific wavelength band (e.g., a wavelength band including red, green, or blue) to pass. In addition, in some embodiments, each CF 134 may include a pigment, a dye, or other light-transmitting material that filters light of one or more wavelength bands.

[0027] On the CF 134 and the sensor dielectric layer 106, a lens layer 110 including a plurality of microlenses 220 may be disposed. Each microlens 220 may correspond to one color pixel 122 or HSPD pixel 120. For example, in some embodiments, each microlens 220 may direct at least some light through the corresponding CF 134 (if present), the sensor dielectric layer 106, the high-K dielectric film 204, and the substrate 102 into one or both PD regions 104 thereunder, depending on the possible presence of the semi-shield 130. In some embodiments, the microlenses 220 may be made of a polymer, an oxide (e.g., SiO2), or other substantially transparent materials.

[0028] Additionally, in some embodiments, an anti-reflective coating (ARC) 222 may be disposed on the microlens 220. In some embodiments, the ARC 222 may be fabricated using titanium nitride (TiN), silicon nitride (SiN), silicon oxynitride (SiON), tantalum pentoxide (Ta2O5), and / or another anti-reflective material that allows light to pass through.

[0029] exist FIG. 2A to FIG. 2F , Figures 3 to 8 as well as Fig.9A and Fig. 9B In the embodiment of the present invention, the various components of the color pixel 122 and the HSPD pixel 120 are not strictly vertically stacked, but are shown as being skewed. More specifically, the microlenses 220, the CF 134, and / or the grid structure (including the grid segments 133 and the half-shield 130) are laterally offset from the PD region 104 associated with each color pixel 122 and the HSPD pixel 120. As described above, in this case, such lateral offsets exist to accommodate the associated pixels to non-zero chief ray angles, such as for pixels that are not located at the center of the pixel array provided by the IC device 100. In these examples, the likelihood of crosstalk from the HSPD pixel 120 (e.g., through reflection from the half-shield 130) to the adjacent color pixel 122 may be increased without the need to incorporate the crosstalk reduction structure employed in the enhanced CF / MG layer 108.

[0030] Figure 2A , Figures 3 to 8 as well as Fig.9A and Fig. 9B A specific embodiment of the IC device 100 is described in which each color pixel 122 and HSPD pixel 120 corresponds to two photodetectors and microlenses 220 of the same size, and in which reflections from the HS 130 are directed to adjacent color pixels 122 that are farther from the HS 130. However, other embodiments are possible. For example, Figure 2B , Figure 2D and Figure 2F As shown, reflections from HS 130 are directed toward adjacent color pixels 122 that are closer to HS 130. Figure 2E and Figure 2F ), each color pixel 122 and HSPD pixel 120 may correspond to a single PD region 104 and associated photodetector. Figure 2C and Figure 2D), a single PD region 104 is associated with each color pixel 122, while two PD regions 104 are associated with each HSPD pixel 120. In such an embodiment, the microlens 220 corresponding to the HS 130 may be larger than the microlens 220 corresponding to the color pixel 122. In other embodiments, more than two PD regions and associated photodetectors may be associated with each color pixel 122 and HSPD pixel 120. FIG. 2A to FIG. 2F , Figures 3 to 8 as well as Fig.9A and Fig. 9B Other configurations of IC device 100 that are compatible with the various crosstalk reduction structure embodiments are also possible.

[0031] FIG. 2A to FIG. 2F Cross-sectional views of some embodiments of IC devices 100A1, 100A2, 100A3, 100A4, 100A5, and 100A6 are shown, respectively. IC devices 100A1, 100A2, 100A3, 100A4, 100A5, and 100A6 include additional color filters 234A, 234B, 234C, 234D, 234E, and 234F, respectively, which serve as crosstalk reduction structures within enhanced CF / MG layers 108A1, 108A2, 108A3, 108A4, 108A5, and 108A6, respectively. More specifically, the additional color filters 234A to 234F can have crosstalk reduction structures with adjacent color pixels 122 (e.g., FIG. 2A to FIG. 2F The color filter 134 of the color pixel 122 to the left of the HSPD pixel 120 in FIG. 1 may have the same color filter spectrum (e.g., filter the same one or more wavelength bands). In some embodiments, as FIG. 2A to FIG. 2F As shown, the additional color filters 234A- 234F may not extend laterally beyond the footprint of HS 130 .

[0032] In some embodiments, FIG. 2A to FIG. 2F As shown by the dashed arrows in , light entering the microlens 220 of the HSPD pixel 120 can be filtered by the additional color filters 234A to 234F, thereby reducing the amount of light encountering the HS 130. The HS 130 can in turn reflect the light back to the microlens 220 of the adjacent color pixel 122, which can reflect the filtered light toward the color filter 134 of the adjacent color pixel 112 through total internal reflection (TIR). The color filter 134 can then further reduce the amount of light that ultimately reaches one of the PD regions 104 of the adjacent color pixel 122. Overall, the inclusion of the additional color filters 234A to 234F can reduce potential crosstalk from the HSPD pixel 120 to the adjacent color pixel 122.

[0033] Figures 3 to 8 as well as Fig.9A and Fig. 9BOther crosstalk reduction structures are used that employ Figure 2A However, in other embodiments, Figures 3 to 8 as well as Fig.9A and Fig. 9B Each crosstalk reduction structure can be adopted FIG. 2B to FIG. 2F pixel structure and half-shielded configuration.

[0034] More specifically, Figure 3 1 shows a cross-sectional view of some embodiments of an IC device 100B that includes an additional color filter 334 that serves as a crosstalk reduction structure within the enhanced CF / MG layer 108B. FIG. 2A to FIG. 2F In comparison, the additional color filter 334 may have a color difference with the adjacent color pixel 122 (e.g., Figure 3 The color filter 134 of the color pixel 122 to the left of the HSPD pixel 120 in the figure may have a different filter spectrum (e.g., filter one or more different wavelength bands). In some embodiments, as Figure 3 As shown, the additional color filters 334 may not extend laterally beyond the footprint of the HS 130 .

[0035] In some embodiments, Figure 3 As shown by the dashed arrows in , light entering the microlens 220 of the HSPD pixel 120 may be filtered by the additional color filter 334, thereby reducing the amount of light encountering the HS 130. The HS 130 may in turn reflect this light back to the microlens 220 of the adjacent color pixel 122, which may reflect the filtered light toward the color filter 134 of the adjacent color pixel 112 via TIR. The color filter 134 may then further reduce the amount of light that ultimately reaches one of the PD regions 104 of the adjacent color pixel 122, particularly because the wavelength band filtered by the color filter 134 may be different from the wavelength band filtered by the additional color filter 334, thereby greatly reducing potential crosstalk from the HSPD pixel 120 to the adjacent color pixel 122.

[0036] Figure 4 1 shows a cross-sectional view of some embodiments of an IC device 100C, which includes an additional color filter 434 used as a crosstalk reduction structure within the enhanced CF / MG layer 108C. More specifically, the additional color filter 434 extends laterally beyond the footprint of the HS 130. For example, the additional color filter 434 can extend from the color filter 134 of the adjacent color pixel 122 (e.g., Figure 4 120) to the left side of the HSPD pixel 120) to the color filter 134 of another adjacent color pixel 112 (e.g., to the right side of the HSPD pixel 120, as shown in FIG. Figure 3In some embodiments, the filter spectrum of the additional color filter 434 may be different from the filter spectrum of the color filter 134 of the adjacent color pixel 122 (e.g., Figure 3 In other embodiments, the filter spectrum of the additional color filter 434 may be the same as the filter spectrum of the color filter 134 of the adjacent color pixel 122 (e.g., as shown in FIG. FIG. 2A to FIG. 2F shown).

[0037] In some embodiments, Figure 4 As shown by the dashed arrows in , since the light passes through the additional color filter 334 material both before and after being reflected by the HS 130 , the additional color filter 434 can filter a large amount of light, thereby greatly reducing the potential crosstalk from the HSPD pixel 120 to the adjacent color pixel 122 .

[0038] Figure 5 1 shows a cross-sectional view of some embodiments of an IC device 100D that includes an anti-reflective coating (ARC) 502 used as a crosstalk reduction structure within the enhanced CF / MG layer 108D. The ARC 502 can be disposed directly on top of the HS 130 and can extend laterally across the HS 130. In some embodiments, the ARC 502 can reduce the amount of light reflected from the upper surface of the HS 130 toward the adjacent color pixel 122, such as Figure 5 In addition, in some embodiments, ARC 502 may include TiN, SiN, SiON, Ta2O5, and / or another anti-reflective material that reduces the amount of light reflected toward adjacent color pixels 122. In addition, in some embodiments, in addition to Figure 2A Additional color filter 234A, Figure 3 Additional color filter 334 or Figure 4 ARC 502 may be provided in addition to any of the additional color filters 434.

[0039] Figure 6A cross-sectional view of some embodiments of an IC device 100E is shown, which includes an anti-reflective coating (ARC) 502 and an ARC 602 used as a crosstalk reduction structure within the enhanced CF / MG layer 108E. In some embodiments, in addition to the ARC 502 located on the top of the HS 130, an ARC 602 can also be placed on the top of each grid segment 133. Moreover, in some embodiments, in addition to the reflected light provided by the ARC 502, the ARC 602 can further reduce the reflected light from the upper surface of the grid segment 133, thereby reducing the crosstalk from the HSPD pixel 120 to the adjacent color pixel 122. Moreover, in some embodiments, the ARC 602 can include TiN, SiN, SiON, Ta2O5, and / or another anti-reflective material that reduces the amount of light reflected from the grid segment 133. Furthermore, in some embodiments, in addition to Figure 2A Additional color filter 234A, Figure 3 Additional color filter 334 or Figure 4 ARCs 502 and 602 may also be provided in addition to any of the additional color filters 434.

[0040] Figure 7 A cross-sectional view of some embodiments of an IC device 100F is shown, which includes an anti-reflective coating (ARC) 702 used as a crosstalk reduction structure within the enhanced CF / MG layer 108F. In some embodiments, the ARC 702 can be disposed on top of the HS 130. In addition, the upper surface of the ARC 702 can be roughened or irregular to further reduce its light reflection. In some embodiments, the upper surface of the ARC 702 can be roughened by acid etching, other types of etching, or other processes that can add or remove material. In addition, in some embodiments, the ARC 702 can include TiN, SiN, SiON, Ta2O5 and / or another anti-reflective material that reduces the amount of light reflected from the HS 130. In addition, in some embodiments, an ARC having a rough upper surface can also be disposed on the grid segment 133. In addition, in some embodiments, in addition to Figure 2A Additional color filter 234A, Figure 3 Additional color filter 334 or Figure 4 ARC 702 may be provided in addition to any of the additional color filters 434.

[0041] Figure 8A cross-sectional view of some embodiments of an IC device 100G is shown, which includes a HS 830 within a HSPD pixel 120, the HS 830 having a roughened or irregular upper surface that serves as a crosstalk reduction structure within the enhanced CF / MG layer 108G to reduce light reflections thereof. In some embodiments, the upper surface of the HS 830 can be roughened by acid etching, other types of etching, or other processes that can add or remove material. In addition, in some embodiments, the upper surface of the grid segment 133 can be similarly roughened to further reduce reflections. Furthermore, in some embodiments, in addition to Figure 2A Additional color filter 234A, Figure 3 Additional color filter 334 or Figure 4 HS 830 may also be provided in addition to any of the additional color filters 434.

[0042] Fig.9A and Fig. 9B 1 shows a cross-sectional view of some embodiments of an IC device 100H including a grid structure having grid segments of different widths, the grid segments serving as crosstalk reduction structures within an enhanced CF / MG layer 108H. More specifically, Fig.9A A cross-sectional view of a HSPD pixel 120 and an adjacent color pixel 122 is provided. Fig. 9B A cross-sectional view of a color pixel 122 that is not adjacent to a HSPD pixel 120 is provided.

[0043] In some embodiments, a color pixel 122 that is not near a HSPD pixel 120 (e.g., Fig. 9B ) may correspond to a grid segment 133 having a width D. In addition, as shown Fig.9A As shown, the color pixel 122 (eg, Fig.9A The color pixel 122 to the right of the HSPD pixel 120 in FIG. 1 may also correspond to a grid segment 133 having a thickness D. Fig.9A As shown in FIG, between an HSPD pixel 120 and an adjacent color pixel 122 that is further from the HS 130 of the HSPD pixel 120 (e.g., a color pixel 122 to the left of the HSPD pixel 120) may be a grid segment 932 having a width D2 greater than D. Additionally, a grid segment 934 associated with the same adjacent color pixel 122 but located further from the HSPD pixel 120 may have a width D1 greater than D or D2. Additionally, the HS 130 of the HSPD pixel 120 may have a width D3 greater than D, D1, or D2.

[0044] In some embodiments, Fig.9AAs shown, D3 can be approximately half the width of the HSPD pixel 120, which can be the distance from a BDTI structure 210 to an adjacent BDTI structure 210. Furthermore, in some embodiments, D1 can be in the range of 1.5D to 2.0D. Furthermore, in some embodiments, D2 can be in the range of 1.1D to 1.5D.

[0045] Widths D2 and D1 of grid segments 932 and 934 , respectively, may prevent some light reflected by HS 130 of HSPD pixel 120 from reaching PD region 104 of adjacent color pixel 122 , while allowing non-adjacent color pixels 122 corresponding to grid segment 133 of width D to receive light more widely.

[0046] Furthermore, in some embodiments, Fig.9A and Fig. 9B The embodiments can be combined with other embodiments described above (for example, Figure 2A and Figures 3 to 8 ) in combination with one or more associated embodiments to further reduce possible crosstalk from the HSPD pixel 120 to the adjacent color pixel 122.

[0047] FIG. 10A to FIG. 10P An IC device (eg, Figure 3 100B) of some embodiments of the IC device. FIG. 10A to FIG. 10P Described as a series of actions, it should be understood that these actions are not restrictive, because in other embodiments, the order of actions within each series can be changed, and the disclosed method is also applicable to other structures. In other embodiments, some actions shown and / or described can be omitted in whole or in part.

[0048] For example, Fig. 10A 1. A substrate 102 (eg, a semiconductor substrate such as a silicon substrate) is shown. In some embodiments, the substrate 102 may be used as a substrate for a backside portion of the IC device 100B, including a sensor dielectric layer 106, a grid structure 132, etc. Figure 1A In addition, the substrate 102 can also be used as a substrate for the front side portion of the IC device 100B, for example Figure 1A To simplify the following discussion, FIG. 10A to FIG. 10P Its existence is not explicitly shown.

[0049] Fig. 10BIt is shown that the PD region 104 is formed (e.g., implanted, doped, etc.) via the front side surface of the substrate 102 to form a corresponding photodetector (e.g., PN photodiode, PIN photodiode, etc.) in combination with the surrounding area of ​​the substrate 102. In some embodiments, the substrate 102 can be a p-type substrate, and the PD region 104 can be an n-doped PD region. In other embodiments, the PD region 104 can be used to form other types of photodetectors in combination with the substrate 102.

[0050] Fig. 10C An STI structure 202 is shown formed (e.g., etched and deposited) on the front side surface of the substrate 102. In some embodiments, the STI structure 202 may be located between each pair of PD regions 104, thereby organizing the PD regions 104 into photodetector pairs, where each pair forms a dual PD pixel. In some embodiments, the STI structure 202 may include silicon oxide (SiO x ) (eg, silicon oxide (SiO 2 )) or another oxide or dielectric material. In some embodiments, the STI structure 202 can help reduce current leakage between consecutive photodetector pairs.

[0051] Fig. 10D The substrate 102 is shown inverted (eg, flipped) such that a backside surface of the substrate 102 opposite the frontside surface is accessible for subsequent processing, as described below with reference to FIG. 10E to FIG. 10N described.

[0052] Fig. 10E A high-K dielectric film 204 is shown formed (e.g., deposited) on an upper surface (e.g., backside) of the substrate 102. As described above, in some embodiments, the high-K dielectric film 204 may include at least one high-K dielectric material, including but not limited to Al2O3, HfO2, ZrO2, TiO2, etc.

[0053] Fig.10F The sensor dielectric layer 106 is shown formed (e.g., deposited) on the high-K dielectric film 204. In some embodiments, the sensor dielectric layer 106 may include, but is not limited to, silicon dioxide (SiO2), another silicon oxide (SiO x ) or another dielectric material. Thereafter, in some embodiments, the upper surface of the sensor dielectric layer 106 may be planarized (eg, by chemical mechanical planarization (CMP)).

[0054] Figure 10GThe formation (e.g., photolithography and associated etching) of a trench 1002 through the sensor dielectric layer 106 and the high-K dielectric film 204 and into the substrate 102 is shown. In some embodiments, the trench 1002 may extend well into the substrate 102 (e.g., two-thirds, three-quarters, etc.). Furthermore, in some embodiments, the trench 1002 may be formed between a PD region 104 and an adjacent PD region 104.

[0055] Fig. 10H The formation (eg, conformal deposition) of an additional high-K dielectric film 218 is shown. In some embodiments, such deposition may allow the high-K dielectric film 218 to cover the upper surface of the sensor dielectric layer 106 and the sidewalls of each trench 1002 .

[0056] Fig.10I The dielectric film 216 is shown formed (e.g., conformally deposited) within each trench 1002 while leaving a void within each trench 1001. In some embodiments, the dielectric film 216 may include, but is not limited to, an oxide (e.g., SiO2, SiO x or other oxides) or other dielectric materials.

[0057] Fig.10J A core 214 is shown formed (e.g., deposited) in the remaining void of each trench 1002. In some embodiments, the core 214 may include a light reflective material, such as one or more metals or oxides, to form a BDTI structure 210. Thus, the BDTI structure 210 may help provide at least some optical isolation between the PD regions 104.

[0058] Figure 10K The additional high-K dielectric film 218 (and light reflective material that may remain from the formation of the core 214) is shown being removed (e.g., blanket etched) from the sensor dielectric layer 106 to expose the upper surface 1004 of the sensor dielectric film 106. In some embodiments, such etching may result in the upper surface of the dielectric film 216 being slightly lower than the upper surface of the core 214 and / or the additional high-K dielectric film 218.

[0059] Fig.10L A metal layer 1006 (eg, copper (Cu) or another metal or metal alloy) is shown formed (eg, deposited) on the sensor dielectric layer 106 and the BDTI structure 210. In other embodiments, a light reflective material other than a metal or metal alloy may be used in place of the metal layer 1006.

[0060] Figure 10M A portion of the metal layer 1006 is shown selectively removed (eg, photolithography and etching) to form a grid structure (eg, Figure 1A and Figure 1B In some embodiments, HS 130 may cover approximately the entire PD region 104, or approximately half of the pixels (e.g., Figure 3 HSPD pixel 120).

[0061] Fig.10N The formation (e.g., deposition) of color filter 134 and additional color filter 334 is shown. In some embodiments, each color filter 134 may be associated with a corresponding color pixel (e.g., Figure 3 122), and the additional color filter 334 may be associated with the corresponding HSPD pixel (eg Figure 3 HSPD pixel 120). As described above, in some embodiments, each CF 134 and additional CF 134 can allow light associated with a specific color (e.g., red, green, or blue) to pass through, thereby filtering other colors. In some embodiments, for each type or color of color filter 134 and 334, the formation of color filter 134 and additional color filter 334 may include applying a color composition layer, selectively patterning (e.g., exposing to ultraviolet (UV) light) the color composition layer, and removing unexposed areas of the color composition layer to form a pattern of CF 134 and 334 having a desired color.

[0062] Furthermore, in some embodiments, Figure 3 As shown, additional color filter 334 covers HS130 to provide a crosstalk reduction structure. In other embodiments, as described above, other types of crosstalk reduction structures may be formed, such as structures associated with other color filters or grid structures (e.g., such as Figure 2A , Figure 4-Figure 8 , Fig.9A and Fig. 9B as shown), to replace or supplement the additional color filter 334.

[0063] Fig.10O The formation (e.g., deposition, patterning, and reflow) of a plurality of microlenses 220 for the lens layer 110 is shown. Each microlens 220 can be configured to focus light to the PD region 104 of the corresponding color pixel 122 or HSPD pixel 120. In some embodiments, the formation of the microlenses 220 can include forming a photosensitive layer of a substantially transparent material (e.g., a polymer, an oxide (e.g., SiO2), or other substantially transparent material), patterning the photosensitive layer, and then reflowing the patterned photosensitive layer (e.g., at a predetermined temperature) to form the microlenses 220.

[0064] Figure 10PAn ARC 222 is shown formed (eg, deposited) on the microlens 220. In some embodiments, the ARC 222 may include, but is not limited to, TiN, SiN, SiON, Ta2O5, and / or other anti-reflective materials that allow light to pass through.

[0065] Fig.11 The invention shows a method for forming a crosstalk reduction structure and IC device (eg, Figure 3 Block diagram of some embodiments of method 1100 of IC device 100B). Although the method and other methods shown and / or described herein are shown as a series of actions or events, it should be understood that the present disclosure is not limited to the order or actions shown. Therefore, in some embodiments, these actions can be performed in a different order than shown, and / or can be performed simultaneously. In addition, in some embodiments, the actions or events shown can be subdivided into multiple actions or events, which can be performed at a separate time or simultaneously with other actions or sub-actions. In some embodiments, some of the actions or events shown can be omitted, and other actions or events not shown can be included.

[0066] At act 1102, on a substrate (eg, Figure 3 A plurality of photodetector groups are formed (doped or implanted) in a substrate 102 (e.g., using Figure 3 Each photodetector group includes one or more photodetectors. In addition, each photodetector group is associated with a plurality of color pixels (e.g., Figure 3 One or more phase detection pixels (e.g., Figure 3 In some embodiments, the substrate may be a semiconductor substrate, such as a silicon substrate. Fig. 10A and Fig. 10B A cross-sectional view of some embodiments corresponding to act 1102 is shown.

[0067] At act 1104, a metal layer (eg, Fig.10L metal layer 1006). Fig.10L A cross-sectional view of some embodiments corresponding to act 1104 is shown.

[0068] At action 1106, the metal layer is etched to form a substrate including a plurality of openings (eg, Figure 1B The grid structure (eg, Figure 1A and Figure 1B Each opening is disposed on a photodetector group. The grid structure also includes a plurality of light shields (e.g., Figure 1A , Figure 1B and Figure 3 HS130 of the present invention). Each light shield is configured to redirect light away from a corresponding photodetector group associated with one of the phase detection pixels. Figure 10M A cross-sectional view of some embodiments corresponding to act 1106 is shown.

[0069] At act 1108, a plurality of color filters (eg, Figure 3 Each color filter is disposed over a corresponding photodetector group associated with one of the color pixels. Fig.10N A cross-sectional view of some embodiments corresponding to act 1108 is shown.

[0070] At act 1110, a crosstalk reduction structure (eg, FIG. 2A to FIG. 2F Additional color filters 234A to 234F, Figure 3 Additional color filter 334, Figure 4 Additional color filter 434, Figure 5 ARC 502, Figure 6 ARC 502 and 602, Figure 7 ARC702, Figure 8 HS 830, Fig.9A 932 and 934 and combinations thereof). This structure limits the amount of light redirected by the light shield of each phase detection pixel to the photodetector group of an adjacent color pixel. Fig.10N A cross-sectional view of some embodiments corresponding to act 1110 is shown (eg, Figure 3 (related to the additional color filter 334).

[0071] In some embodiments, the present disclosure provides an IC device, comprising: a substrate, comprising a plurality of first photodetector groups respectively associated with a plurality of color pixels and a plurality of second photodetector groups respectively associated with a plurality of phase detection pixels, wherein each of the first photodetector groups and the second photodetector groups comprises one or more photodetectors; a grid structure located on the substrate, wherein the grid structure comprises a plurality of light shields, each of the light shields being configured to redirect light away from a corresponding one of the second photodetector groups; a plurality of color filters located on the substrate, each of the color filters vertically spanning the grid structure at a corresponding one of the first photodetector groups; and a crosstalk reduction structure transverse to the color filters and limiting the amount of light redirected by the light shield of each of the phase detection pixels to the first photodetector group of an adjacent one of the color pixels. In some embodiments, the crosstalk reduction structure comprises a plurality of additional color filters, each located on top of a corresponding one of the light shields. In some embodiments, in a plan view of the IC device, each of the additional color filters is completely within the footprint of a corresponding one of the light shields. In some embodiments, each of the additional color filters extends through the grid structure at a corresponding one of the light shields. In some embodiments, each of the additional color filters has a color filter spectrum that is the same as the color filter spectrum of the color filter corresponding to an adjacent one of the color pixels. In some embodiments, each of the additional color filters has a color filter spectrum that is different from the color filter spectrum of the color filter corresponding to an adjacent one of the color pixels. In some embodiments, the crosstalk reduction structure includes an anti-reflective coating disposed on each of the light shields. In some embodiments, the anti-reflective coating includes a non-planar upper surface facing away from the substrate. In some embodiments, the crosstalk reduction structure includes an anti-reflective coating disposed on the entire grid structure. In some embodiments, the crosstalk reduction structure includes a non-planar upper surface of each of the light shields, the non-planar upper surface facing away from the substrate. In some embodiments, the crosstalk reduction structure includes a plurality of grid segments of the grid structure, the width of the grid segments increasing as they move away from the phase detection pixel. In some embodiments, the grid segments include: a first grid segment located between one of the phase detection pixels and one of the color pixels adjacent to the phase detection pixel, wherein the first grid segment has a first width; and a second grid segment located between the one color pixel and the adjacent color pixel, wherein the second grid segment has a second width greater than the first width. In some embodiments, the grid segments further include: a third grid segment disposed on a side of one of the phase detection pixels opposite to the first grid segment, wherein the third grid segment has a third width less than the second width.

[0072] In some embodiments, the present disclosure provides another IC device, comprising: a substrate including a first at least one photodetector and a second at least one photodetector adjacent to the first at least one photodetector, the first at least one photodetector being associated with a phase detection pixel, the second at least one photodetector being associated with a color pixel; a grid structure located above the substrate, the grid structure comprising: a light shield located above a first portion of the first at least one photodetector; a first opening located above a second portion of the first at least one photodetector, the second portion being different from the first portion; and a second opening located above the second at least one photodetector; a color filter located above the second at least one photodetector in the second opening; and a crosstalk reduction structure, lateral to the color filter and configured to limit light redirected by the light shield to the second at least one photodetector. In some embodiments, the crosstalk reduction structure comprises an additional color filter on the light shield. In some embodiments, the crosstalk reduction structure comprises an anti-reflection coating on the light shield. In some embodiments, the crosstalk reduction structure comprises a non-planar upper surface of the light shield, the non-planar upper surface facing away from the substrate.

[0073] In some embodiments, the present disclosure provides a method, comprising: forming a plurality of photodetector groups in a substrate, each of the photodetector groups including one or more photodetectors, each of the photodetector groups being associated with one of one or more phase detection pixels in a plurality of color pixels; depositing a metal layer on the substrate; etching the metal layer to form a grid structure comprising a plurality of openings, each of the openings being disposed on one of the photodetector groups, and further comprising a plurality of light shields, each of the light shields being configured to redirect light away from a corresponding photodetector group associated with one of the phase detection pixels; forming a plurality of color filters above the grid structure, each of the color filters being disposed on a corresponding photodetector group associated with one of the color pixels; and forming a crosstalk reduction structure, the crosstalk reduction structure being transverse to the plurality of color filters and limiting the amount of light redirected by the light shield of each phase detection pixel to the photodetector group of an adjacent one of the color pixels. In some embodiments, the crosstalk reduction structure comprises a plurality of additional color filters, each of the color filters being disposed on a corresponding one of the light shields. In some embodiments, the crosstalk reduction structure comprises an anti-reflective coating disposed on each of the light shields.

[0074] It should be understood that in this written description and in the claims that follow, the terms "first," "second," "third," etc., are merely general identifiers used for ease of description to distinguish different elements of a figure or series of figures. By themselves, these terms do not imply any temporal order or structural proximity of these elements, nor are they intended to describe corresponding elements in different illustrated embodiments and / or embodiments not shown. For example, a "first dielectric layer" described in conjunction with a first figure may not necessarily correspond to a "first dielectric layer" described in conjunction with another figure, and may not necessarily correspond to a "first dielectric layer" in an embodiment not shown.

[0075] The features of several embodiments are summarized above so that those skilled in the art can better understand the various aspects of the present disclosure. Those skilled in the art will appreciate that they can easily use the present disclosure as a basis for designing or modifying other processes and structures for achieving the same purpose of the embodiments introduced herein and / or achieving the same advantages thereof. Those skilled in the art will also appreciate that such equivalent structures do not deviate from the spirit and scope of the present disclosure, and that they can make various changes, substitutions, and changes in the present disclosure without departing from the spirit and scope of the present disclosure.

Claims

1. An integrated circuit device, comprising: a substrate comprising a plurality of first photodetector groups respectively associated with a plurality of color pixels and a plurality of second photodetector groups respectively associated with a plurality of phase detection pixels, wherein each of the first photodetector groups and the second photodetector groups comprises one or more photodetectors; a grid structure disposed on the substrate, wherein the grid structure comprises a plurality of light shields, each of the light shields being configured to redirect light away from a corresponding one of the second photodetector groups; a plurality of color filters disposed on the substrate, each of the color filters vertically spanning the grid structure at a corresponding one of the first photodetector groups; and A crosstalk reduction structure is lateral to the color filter and limits the amount of light redirected by the light shield of each of the phase detection pixels to the first photodetector group of an adjacent one of the color pixels.

2. The integrated circuit device according to claim 1, wherein: The crosstalk reduction structure includes a plurality of additional color filters, each of which is located on the top of a corresponding one of the light shields.

3. The integrated circuit device according to claim 2, wherein: In a plan view of the integrated circuit device, each of the additional color filters is located entirely within a footprint of a corresponding one of the light shields.

4. The integrated circuit device according to claim 2, wherein: Each of the additional color filters has a color filter spectrum different from a color filter spectrum of a color filter corresponding to an adjacent one of the color pixels.

5. The integrated circuit device according to claim 1, wherein: The crosstalk reduction structure includes an anti-reflective coating disposed on each of the light shields.

6. The integrated circuit device according to claim 1, wherein: The crosstalk reduction structure includes a non-planar upper surface of each of the light shields, the non-planar upper surface facing away from the substrate.

7. The integrated circuit device according to claim 1, wherein: The crosstalk reduction structure includes a plurality of grid segments of the grid structure, the widths of the grid segments increasing as they move away from the phase detection pixel.

8. The integrated circuit device according to claim 7, wherein: The grid segments include: a first grid segment located between one of the phase detection pixels and one of the color pixels adjacent to the phase detection pixel, wherein the first grid segment has a first width; and The second grid segment is located between the one color pixel and an adjacent one of the color pixels, wherein the second grid segment has a second width greater than the first width.

9. An integrated circuit device comprising: a substrate including a first at least one photodetector and a second at least one photodetector adjacent to the first at least one photodetector, the first at least one photodetector being associated with a phase detection pixel and the second at least one photodetector being associated with a color pixel; A grid structure, located above the substrate, comprises: a light shield positioned over the first portion of the first at least one photodetector; a first opening located above a second portion of the first at least one photodetector that is different from the first portion; and a second opening located above the second at least one photodetector; a color filter positioned over the second at least one photodetector in the second opening; and A crosstalk reduction structure is lateral to the color filter and is configured to limit light redirected by the light shield to the second at least one photodetector.

10. A method of manufacturing an integrated circuit device, comprising: forming a plurality of photodetector groups in a substrate, each of the photodetector groups comprising one or more photodetectors, each of the photodetector groups being associated with one of the one or more phase detection pixels in the plurality of color pixels; depositing a metal layer on the substrate; etching the metal layer to form a grid structure including a plurality of openings, each of the openings being disposed over one of the photodetector groups, and further comprising a plurality of light shields, each of the light shields being configured to redirect light away from a respective photodetector group associated with one of the phase detection pixels; forming a plurality of color filters over the grid structure, each of the color filters being disposed over a respective photodetector group associated with one of the color pixels; as well as A crosstalk reduction structure is formed transverse to the plurality of color filters and limits the amount of light redirected by the light shield of each of the phase detection pixels to the photodetector group of an adjacent one of the color pixels.

Images