Integrated circuit optical sensing device

Abstract

Some embodiments relate to integrated circuit light sensor devices. An integrated circuit light sensor device includes a semiconductor substrate and a plurality of first light absorption regions and a plurality of second light absorption regions on the semiconductor substrate. Each first light absorption region comprises an injection region of the semiconductor substrate, the injection region and the semiconductor substrate form at least one part of a corresponding one of the plurality of first light detectors, and the injection region and the semiconductor substrate are used for a first light wave band; each second light absorbing region includes a semiconductor material different from the semiconductor substrate, the semiconductor material forming at least a portion of a corresponding one of the plurality of second light detectors for a second light band different from the first light band.

Description

TECHNICAL FIELD

[0001] Embodiments of the present application relate to integrated circuit light sensing devices. BACKGROUND

[0002] Optical sensing modules (e.g., camera modules) are commonly used in a variety of electronic devices (e.g., smartphones, webcams, tablet computers, notebook computers, or the like) to capture optical images, such as two-dimensional visible light images. Such modules typically include an integrated circuit light sensing device, a lens assembly including one or more lenses, and supporting electronic components (e.g., interface electronics, a digital signal processor (DSP), etc.). SUMMARY

[0003] Embodiments of the present application relate to integrated circuit light sensing devices. An integrated circuit light sensor includes a semiconductor substrate and a plurality of first light absorption regions and a plurality of second light absorption regions in the semiconductor substrate. Each first light absorption region includes an implanted region of the semiconductor substrate, the implanted region and the semiconductor substrate forming at least a portion of a corresponding set of first light detectors for a first light wavelength band; and each second light absorption region includes a semiconductor material different from the semiconductor substrate, the semiconductor material forming at least a portion of a corresponding set of second light detectors for a second light wavelength band different from the first light wavelength band.

[0004] Embodiments of the present application relate to integrated circuit light sensing devices. An integrated circuit light sensor includes a semiconductor substrate and a plurality of first light absorption regions and a plurality of second light absorption regions in the semiconductor substrate. Each first light absorption region includes an implanted region of the semiconductor substrate, the implanted region and the semiconductor substrate forming at least a portion of a corresponding set of first light detectors for a first light wavelength band; and each second light absorption region includes a semiconductor material different from the semiconductor substrate, the semiconductor material forming at least a portion of a corresponding set of second light detectors for a second light wavelength band different from the first light wavelength band. BRIEF DESCRIPTION OF DRAWINGS

[0005] Various features will become apparent to those of ordinary skill in the art upon reading the following detailed description, the preferred embodiment of the application being illustrated in the accompanying drawings. It should be noted, however, that the drawings are not to scale, as the dimensions of various features have been exaggerated or reduced for the sake of clarity. It should further be noted that the drawings and descriptions are not intended to limit the scope of the application to the specific embodiments presented, but rather, the scope of the application includes all the implied variations and alternate embodiments.

[0006] Figure 1 A block diagram illustrating some embodiments of a light sensor module according to the present disclosure, including a multiple wavelength band light sensor IC.

[0007] Figure 2 A sub-pixel layout diagram illustrating some embodiments of a multiple wavelength band light sensor IC according to the present disclosure.

[0008] Figure 3A A sub-pixel layout diagram illustrating some embodiments of a multiple wavelength band light sensor IC according to the present disclosure. Figure 2 A single pixel layout diagram illustrating some embodiments of a multiple wavelength band light sensor IC according to the present disclosure.

[0009] Figure 3B A single pixel layout diagram illustrating some embodiments of a multiple wavelength band light sensor IC according to the present disclosure. Figure 3A A cross-sectional view of a single pixel illustrating some embodiments according to the present disclosure.

[0010] Figures 4A to 4O Cross-sectional views of some semiconductor structure embodiments illustrating different stages of fabrication of a multiple wavelength band light sensor IC according to the present disclosure.

[0011] Figure 5 A method of forming a multiple wavelength band light sensor IC according to some embodiments of the present disclosure. DETAILED DESCRIPTION

[0012] The following disclosure provides many different embodiments, or examples, for implementing different features of the present disclosure. Specific examples of components and configurations are described below to simplify the present disclosure. These are, of course, merely examples and are not intended to be limiting. For example, in the following description, formation of a first feature over or on a second feature can include embodiments in which the first feature is formed directly on the second feature, and can also include embodiments in which additional features can be formed between the first and second features such that the first and second features can not be directly in contact. Additionally, the present disclosure can repeat reference numerals and / or letters in various examples. This repetition is for the purpose of simplicity and clarity and does not in itself dictate a relationship between the various embodiments and / or configurations discussed.

[0013] Moreover, spatially relative terms, such as "under", "below", "lower", "over", "upper" and the like, can be used herein for ease of description to describe one element or feature's relationship to another element(s) or feature(s) as illustrated in the figures. The spatially relative terms are intended to encompass different orientations of the device in use or operation in addition to the orientation depicted in the figures. The devices can be otherwise oriented (rotated 90 degrees or at other orientations) and the spatially relative descriptions used herein interpreted accordingly.

[0014] A common light-sensing module (e.g., a camera module, a complementary metal-oxide semiconductor (CMOS) image sensor (CIS), or the like) typically includes a lens assembly optically aligned or coupled with a light-sensing IC, such that light received by the lens assembly is directed and / or focused on the light-sensing IC. Supportive electronic components in the light-sensing module can then facilitate correction and possible processing of data retrieved from light received at various locations around the light-sensing IC. As used herein, the term "light" can apply to the visible or non-visible (e.g., infrared, ultraviolet, etc.) portions of the electromagnetic spectrum.

[0015] Generally, a light-sensing IC can be limited to sensing a particular light wavelength band (e.g., a portion of the human eye visible spectrum). In some cases, such limitations can be more applicable to different semiconductor materials or configurations for different light wavelength bands. For example, a relatively thick silicon substrate can be advantageous for photo-induced electron transfer (PET) for short-wavelength infrared (SWIR) sensing ICs, but not practical for PET in the visible light (red-green-blue (RGB)) spectrum. On the other hand, germanium, which provides a lower energy bandgap than silicon, can be suitable for SWIR sensing ICs where sensitivity is of significant importance, but can also cause high dark current (e.g., providing current in the absence of photons) and excessive white pixels in visible light sensing ICs. Thus, multiple light-sensing modules or light-sensing modules with multiple light-sensing ICs, lens assemblies, and the like can be needed to allow for sensing light in multiple wavelength bands.

[0016] To address these issues, this invention provides embodiments of multi-band optical sensing ICs that integrate multiple semiconductor materials within a single semiconductor substrate. In some embodiments, such sensing ICs can be configured within an optical sensing module having a single lens group and associated supporting electronics, thereby reducing overall cost and the physical footprint of the optical sensing solution.

[0017] Figure 1 The diagram illustrates an embodiment of an optical sensing module 110 according to the present invention, including a multi-band optical sensing IC 100. Hereinafter, the multi-band optical sensing IC 100 may also be simply referred to as optical sensing IC 100. In addition to the optical sensing IC 100, the optical sensing module 110 may include a lens group 108 (e.g., one or more lenses) configured to receive and directly direct light toward the optical sensing IC 100. The optical sensing module 110 may also include supporting electronic components 106 (e.g., a DSP, interface circuitry, etc.) to allow the capture and retrieval of sensing data from the optical sensing IC 100.

[0018] like Figure 1 As shown, the optical sensing IC 100 may include a visible light sensor 102 sensitive to visible light (VL) and an infrared light sensor 104 sensitive to infrared light (IR) 114 via a lens group 108. In some embodiments, the IR sensor 104 may be adapted to detect SWIR light. In some embodiments, each VL sensor 102 and IR sensor 104 may include a plurality of separate subpixels (e.g., distributed in a two-dimensional array) distributed therein. Furthermore, the subpixel group may be organized into pixels, each of which is associated with a specific portion of the image captured by the VL sensor 102 and IR sensor 104.

[0019] Figure 2 The diagram illustrates a subpixel layer planar view of some embodiments of a multi-band optical sensing IC 100. For example... Figure 2As shown, the photosensitive IC 100 can include a plurality of SWIR sub-pixels 202 interleaved with a plurality of VL sub-pixels including red sub-pixels 212, green sub-pixels 214, and blue sub-pixels 216. Each of the plurality of VL sub-pixels 212, 214, and 216 is configured to have sensitivity for capturing a visible light bandwidth encompassing a designated color. In some embodiments, the plurality of SWIR sub-pixels 202 and the plurality of VL sub-pixels 212, 214, and 216 are each configured as a two-dimensional array (e.g., in a plurality of rows and columns) to provide a corresponding two-dimensional image. Further, the two arrays can be slightly offset from each other such that the SWIR sub-pixels 202 and the VL sub-pixels 212, 214, and 216 do not overlap in a plan view. In other embodiments, different arrangements of the SWIR sub-pixels 202 and the VL sub-pixels 212, 214, and 216 can be employed. Moreover, instead of each SWIR sub-pixel 202 and VL sub-pixel 212, 214, and 216 having a substantially circular shape in a plan view, in other embodiments, the SWIR sub-pixels 202 and the VL sub-pixels 212, 214, and 216 can have other shapes in a plan view, such as square, rectangular, polygonal, etc.

[0020] In some embodiments, each SWIR sub-pixel 202 can be larger than a corresponding VL sub-pixel 212, 214, and 216 (to compensate for the lower quantum efficiency (QE) of the SWIR sub-pixels 202 relative to the VL sub-pixels 212, 214, and 216). In some embodiments, as shown, each SWIR sub-pixel 202 can be closely located with each adjacent SWIR sub-pixel 202 in either a row direction or a column direction. Such a configuration can allow each VL sub-pixel 212, 214, and 216 to be located between each two-by-two group of SWIR sub-pixels 202 without overlapping, as shown. Figure 2 Figure 2 In some embodiments, a width or diameter of each SWIR sub-pixel 202 can be in a range of 1 micrometer (pm) to 20 micrometers (pm), and a width or diameter of each VL sub-pixel 212, 214, and 216 can be in a range of 0.1 micrometer (pm) to 2 micrometers (pm). That is, in some embodiments, a ratio of a diameter of each SWIR sub-pixel 202 to a diameter of each VL sub-pixel 212, 214, and 216 can be in a range of about 5: 1 to about 1.5: 1, and in some cases can be about 2.4: 1.

[0021] FIG. 3 illustrates a plan view of a photosensitive IC 300 including a plurality of SWIR sub-pixels 302 and a plurality of VL sub-pixels 312, 314, and 316, according to some embodiments. Figure 2 ​A plan view of a sub-pixel configuration of a single pixel 100A of some embodiments of the multi-band light-sensing IC 100. The single pixel 100A includes four SWIR sub-pixels 202 in a two-by-two configuration and four VL sub-pixels 212, 214, and 216 (e.g., one red sub-pixel 212, two green sub-pixels 214, and one blue sub-pixel 216) in another two-by-two configuration, that is, each of the plurality of SWIR sub-pixel groups includes four groups of the plurality of SWIR light detectors in a two-by-two configuration, and each of the plurality of VL sub-pixel groups includes four groups of the plurality of VL light detectors in a two-by-two configuration. Meanwhile, in some embodiments, the two-by-two configurations can be offset from each other, as shown in FIG. 3, such that the SWIR sub-pixels 202 and the VL sub-pixels 212, 214, and 216 do not overlap and are each located within some area associated with the single pixel 100A.

[0022] In some embodiments, two green sub-pixels 214 can be used in the single pixel 100A to mimic the enhanced sensitivity of the human eye to the green portion of the visible spectrum relative to one red sub-pixel 212 and one blue sub-pixel 216.

[0023] Figure 3B A cross-sectional view of an embodiment of the single pixel 100A of some multi-band light-sensing ICs is illustrated along the section line A-A as shown in Figure 3A . Thus, the cross-sectional view includes two SWIR sub-pixels 202, one red sub-pixel 212, and one blue sub-pixel 216. In some embodiments, the green sub-pixels 214 of the single pixel 100A can have the same structure as one or both of the red sub-pixel and the blue sub-pixel, which are not shown in Figure 3B .

[0024] As shown in the configuration of Figure 3B , the single pixel 100A of the light-sensing IC 100 can include a filter / lens (e.g., in the form of a microlens) for each sub-pixel and be attached (e.g., with an adhesive) to the backside of the semiconductor substrate 310. In some embodiments, in the plan view of the semiconductor substrate 310, each microlens defines an area of its associated sub-pixel with a location (e.g., as shown in Figure 3A ). For example, a SWIR microlens 322 can be used for the associated SWIR sub-pixel 202, a red microlens 302 can be used for the associated red sub-pixel 212, and a blue microlens 312 can be used for the associated blue sub-pixel 216. In addition, the single pixel 100A can also include a green microlens for each green sub-pixel 214, which is not shown in Figure 3B . In some embodiments, each microlens 302, 312, and 322 can be configured to focus light (e.g., from a light source) onto its associated sub-pixel.Figure 1 The lenslets 302, 312, and 322 direct the light rays (e.g., the light rays received by the lens group 108) toward their associated sub-pixels. As Figure 3B mentioned, the lenslets 302, 312, and 322 can be spherical lenslets, although other lens types can be acceptable. Further, in some embodiments, each lenslet 302, 312, and 322 can be configured to filter the received light rays to pass light rays related to its associated sub-pixel. For example, the lenslet 302 can be configured to pass red portion wavelengths of the electromagnetic spectrum, the lenslet 312 can be configured to pass blue portion wavelengths of the spectrum, and the lenslet 322 can be configured to pass SWIR portion wavelengths of the spectrum. In other embodiments, the efficacy of the filters and lenslets can be decoupled from the structure of the corresponding filters and lenslets.

[0025] In some embodiments, based on the operation of the lenslets, the red wavelengths of the visible light 112 will be directed to photodetectors associated with each red sub-pixel 212, the green wavelengths of the visible light 112 will be directed to photodetectors associated with each green sub-pixel 214, the blue wavelengths of the visible light 112 will be directed to photodetectors associated with each blue sub-pixel 216, and the SWIR wavelengths of the IR light 114 will be directed to photodetectors associated with each SWIR sub-pixel 202. Thus, as Figure 3B mentioned, under each lenslet 302, 312, and 322, a semiconductor photodetector structure (e.g., a photodiode) is placed, which structure is embedded in the semiconductor substrate 310, each of the plurality of visible light associated photodetectors being adjacent to a corresponding one of the plurality of SWIR light associated photodetectors.

[0026] In some embodiments, each VL sub-pixel 212, 214, and 216 can include a light absorption region that includes an implantation region 304 that, in combination with the semiconductor substrate 310, forms a photodiode that is sensitive to a visible light band (e.g., the visible light 112 frequency band). For example, the semiconductor substrate 310 can be P-type silicon, and the implantation region 304 can be a portion of the semiconductor substrate 310 that has been ion implanted or doped to create an N-type doped region. In some embodiments, the photodiode resulting from the formation of the implantation region 304 and its associated photodiode junction can be a PN photodiode (e.g., a PIN photodiode) that is sensitive to visible light photons.

[0027] Also, in some embodiments, each SWIR sub-pixel 202 can include a light absorption region that includes a semiconductor material that is different from the semiconductor substrate and that forms a photodiode that is sensitive to the SWIR band (e.g., the bandwidth of the IR light 114). For example, portions of the semiconductor substrate 310 can be etched and substantially filled with a different semiconductor material 324 (e.g., P-type Germanium). In some embodiments, the etched regions or cavities of the different semiconductor material can have beveled edges, as shown. The different semiconductor material 324 that fills the associated cavities can then be implanted or doped with ions to create at least one N-type implant region 325. In some embodiments, the plurality of photodiodes and the photodiode interface of each of the plurality of photodiodes can be PIN-type photodiodes that are sensitive to SWIR light, created from the formation of the different semiconductor material 324 and the associated implant region 325. Figure 3B

[0028] Based on the plurality of structures embedded in the semiconductor substrate 310 (e.g., the implant region 304 and the different semiconductor material 324 and the associated implant region 325), a single semiconductor substrate 310 (and thus, a single photosensor IC 100) can embed at least two groups of photodetectors, where each group of photodetectors can be sensitive to a different light band of light.

[0029] In some embodiments, the implant region 304, the different semiconductor material 324 and the associated implant region 325 can be circular in shape in plan view (e.g., can receive light from the directions of the visible light 112 and the IR light 114 broadly). This shape can align with the overall circular shape of the microlenses 302, 312 and 322 discussed previously. However, in other embodiments, the different semiconductor material 324 and the associated implant region 325 can also have other shapes.

[0030] In some embodiments, the implant region 304, the different semiconductor material 324 and the associated implant region 325 can be formed through the front side of the semiconductor substrate 310. Thus, in some embodiments, the implant region 304, the different semiconductor material 324 and the associated implant region 325 are accessible through the front side (e.g., with a semiconductor layer, a contact or similar) to facilitate control of the photodetectors in the semiconductor substrate 310.

[0031] ​For example, in some embodiments, a gate structure 332 and associated sidewall spacer 334 can be formed over the semiconductor substrate 310 adjacent to the implant region 304 of the associated visible light photodetector. In some embodiments, the gate structure 332 can be made of poly-Si. Meanwhile, in some embodiments, the gate structure 332 can be controlled as a transmission gate to transmit charges received by the photodiode during a certain period to a measurement node through a measurement contact 333 adjacent to the gate structure 332.

[0032] In some embodiments, an interconnect structure 339 is configured over the front side. The interconnect structure 339 includes contacts 335 and 337, which can be formed over different semiconductor materials 324 and associated implant regions 325 to be used as cathodes and anodes of the associated SWIR photodiodes, respectively, that is, at least one of the anodes is configured on the semiconductor material of each of the SWIR photodiodes. In some embodiments, the contacts 335 and 337 can be formed over the different semiconductor materials 324 and associated implant regions 325 to be used as cathodes and anodes of the associated SWIR photodiodes, respectively, that is, at least one of the anodes is configured on the semiconductor material of each of the SWIR photodiodes. Figure 3B In some embodiments, the contacts 335 and 337 can be at least partially circular in plan view, thus the contact 335 can be a full opposite side of a single circular cathode, while the contact 337 can be a full opposite side of a single circular anode. Such circular shape can substantially conform to the circular semiconductor materials 324 and associated implant regions 325. In comparison, the contacts 335 and 337 can have other shapes in other embodiments. For example, as seen in plan view, for rectangular semiconductor materials 324 and associated implant regions 325, the contact 337 can be a plurality of separate contacts located at opposite ends of the different semiconductor materials 324, and the contact 335 can be a plurality of separate contacts located at opposite ends of the associated implant regions 325. Figure 3B In some embodiments, the contact 336, which includes the contacts 333, 335, and 337, can be formed in a dielectric material layer 330 to couple regions within the semiconductor substrate to one or more metal structures. Meanwhile, in some embodiments, one or more additional metal structures 342 can be coupled to the one or more metal structures 338 by vias. In some embodiments, the metal structures 338 and 342 can couple the photodetectors in the semiconductor substrate 310 to a light sensing module (e.g., an image sensor) and / or a light source (e.g., a light emitting diode).

[0033] In some embodiments, a contact 336, which includes the contacts 333, 335, and 337, can be formed in a dielectric material layer 330 to couple regions within the semiconductor substrate to one or more metal structures. Meanwhile, in some embodiments, one or more additional metal structures 342 can be coupled to the one or more metal structures 338 by vias. In some embodiments, the metal structures 338 and 342 can couple the photodetectors in the semiconductor substrate 310 to a light sensing module (e.g., an image sensor) and / or a light source (e.g., a light emitting diode).Figure 1 Supporting circuitry for the optical sensing module 110 (e.g., Figure 1 Supporting electronic components 106 are used to retrieve and process sensing data provided by the multiple photodiodes. For example, some components of the metal structures 338 and 342 can serve as row and column select lines for accessing specific photodiodes.

[0034] Figures 4A to 4O The illustration shows cross-sectional views of some embodiments of the semiconductor structure for a multi-band optical sensing IC 100 at different manufacturing stages. Although Figures 4A to 4O A series of operations are described, but please understand that the order of these operations is not limited and cannot be replaced in other embodiments, and the disclosed methods are also applicable to other structures. In other embodiments, some of the operations illustrated and / or described may be omitted in whole or in part.

[0035] Figure 4A The portion shown is an executable semiconductor substrate, which can serve as such Figures 4A to 4O The underlying structure of the additional processing operations. More specifically, Figures 4B to 4N The illustration depicts multiple processing operations on the semiconductor substrate 310 and the subsequent layers described above, resulting in an appearance opposite to... Figure 3B The resulting structure of the final structure shown.

[0036] The semiconductor substrate 310 can be p-doped silicon (p-Si), although other materials can be used in other embodiments. Meanwhile, in some embodiments, the semiconductor substrate 310 is shown as a semiconductor wafer, and its dimensions can be, for example, 1 inch (25 mm), 2 inches (51 mm), 3 inches (76 mm), 4 inches (100 mm), 5 inches (130 mm), or 125 mm (4.9 inches), 150 mm (5.9 inches, commonly referred to as "6 inches"), 200 mm (7.9 inches, commonly referred to as "8 inches"), 300 mm (11.8 inches, commonly referred to as "12 inches"), or 450 mm (17.7 inches, commonly referred to as "18 inches"). After the process is completed (e.g., as described below, with...), Figures 4B to 4O (Related to this), this chip can be selectively stacked on other chips and then monolithically converted into individual chips relative to each IC.

[0037] Figure 4 illustrates the formation of implant regions 304 in a semiconductor substrate 310 to create the visible light detectors discussed above. In some embodiments, a mask is positioned over the semiconductor substrate 310 and gaps or holes are defined through the semiconductor substrate 310. Then, an ion implantation beam 351 can be directed at the mask 303 and the semiconductor substrate 310 to create implant regions 304 at desired locations in the semiconductor substrate 310. In some embodiments, the ion beam 351 creates N-type regions as implant regions 304. Meanwhile, in some embodiments, portions of the implant regions 304 can appear as intrinsic (undoped) semiconductor regions (e.g., due to N-doping of a P-type semiconductor substrate 310). In plan view of the semiconductor substrate 310, the implant regions 304 can be distributed in a two-dimensional layout corresponding to the layout of the VL sub-pixels 212, 214, and 216. Figure 2 corresponding to the layout of the VL sub-pixels 212, 214, and 216.

[0038] Figure 4C Figure 5 illustrates gate structures 332 and surrounding sidewall spacers formed on the semiconductor substrate to form implant regions 304. In some embodiments, each gate structure 332 and associated sidewall spacer 334 is positioned next to or adjacent to a corresponding implant region 304, that is, each of the plurality of gate structures is adjacent to a corresponding one of the plurality of photodiodes (the implant regions 304 in combination with the semiconductor substrate 310 form the photodiodes). The gate structures are used as charge transport gates to facilitate the use of the gate structures, as described above. In some embodiments, the sidewall spacers 334, which can be conformally formed next to the gate structures 332, provide separation between the gate structures 332 and subsequently formed adjacent contact windows 333. In some embodiments, the gate structures 332 can be polysilicon structures.

[0039] Figure 4D Figure 6 illustrates the creation (e.g., etching) of cavities 323, each of which corresponds to a location of a different semiconductor material 324 associated with each SWIR light detector. In some embodiments, the cavities 323 are arranged in a two-dimensional layout corresponding to the two-dimensional layout of the SWIR sub-pixels 202 as described above. In some embodiments, each cavity 323 can appear as a circle in plan view of the semiconductor substrate 310. Meanwhile, in some embodiments, each cavity 323 can have sloped sidewalls such that each cavity 323 describes a middle portion of an inverted cone or a frustum. However, different shaped cavities 323 are also possible in other embodiments. Figure 2

[0040] Figure 4E ​The illustration shows the cavity 323 filled with different semiconductor materials 324. As mentioned above, in some embodiments, the different semiconductor materials 324 can be germanium (e.g., P-type germanium) and can be completed by epitaxial growth. In some embodiments, germanium can be a semiconductor material more suitable for forming a photodetector (e.g., a photodiode) for sensing IR light 114 (e.g., SWIR light), while silicon can be a semiconductor material more suitable for forming a photodetector for sensing visible light 112 (e.g., wavelengths of red, green, and blue light), as described above.

[0041] In some embodiments, such as Figures 4B to 4E As shown, the creation of the implantation region 304 and the formation of the gate structure 332 and associated sidewall spacers 334 allows the cavity 323 to be filled with a different semiconductor material 324 prior to etching. This sequence of operations can be used in high-temperature processes that may involve temperatures that could damage the different semiconductor material 324. For example, if the different semiconductor material 324 is germanium (melting point approximately 938 degrees Celsius), a higher-temperature process before the cavity 323 is filled could distort or damage any of the germanium.

[0042] Figure 4F The illustration depicts the formation of implantation regions 325 within different semiconductor materials 324 to create the SWIR photodiode discussed above. In some embodiments, a shield 313 is located on a semiconductor substrate 310 and is equipped with holes, thus coinciding with the area occupied by the different semiconductor materials 324. An ion beam 361 can then be directed to the shield 313 and the semiconductor substrate 310 to create the implantation regions 325. In some embodiments, the ion beam creates an N-type germanium region as the implantation region 325. Meanwhile, in some embodiments, the implantation region 325 may be partially represented as an intrinsic semiconductor region (e.g., due to N-doping of the P-type different semiconductor materials 324).

[0043] Figure 4G The illustration shows the formation of a dielectric material layer 330 (e.g., silicon dioxide) on the semiconductor substrate 310 and the related structures described above as insulating structures.

[0044] Figure 4HA contact 336 is shown formed (e.g., etched and then deposited and / or chemical mechanical planarization (CMP)) in the dielectric material layer 330 for electrically coupling multiple structures (e.g., semiconductor substrate 310, implant region 304, gate structure 332, different semiconductor material 324, and implant region 335). As described above, the contact 336 includes a contact for the gate structure 332 as well as contacts 333 (e.g., for the VL photodiode) and contacts 335 and 337 (e.g., for the SWIR photodiode as anode and cathode).

[0045] Subsequently, Figure 4I An additional dielectric material 330 is shown formed, and Figure 4J A metal layer (Ml) is shown formed (e.g., etched and then deposited) Figure 4I Metal structures 338 in the additional dielectric material 330; Figure 4K The remaining additional dielectric material 330 is shown formed, and Figure 4L Conductive vias 340 are shown formed (e.g., using etching and deposition and / or chemical mechanical planarization (CMP)) in the dielectric material 330. Subsequently, Figure 4M More dielectric material 330 is shown formed on the previously assembled structure, and Figure 4N A second metal layer (M2) is shown formed (e.g., by etching and deposition and / or CMP). In some embodiments, the metal structures 338 and 342 and / or vias 340 can be formed from one or more conductive materials (e.g., copper). The metal structures 338, 342, and vias 340 can collectively form conductive structures (e.g., row and column select lines, data capture lines, etc.) for coupling the VL and SWIR photodiode structures. The support circuitry can include timing circuitry for capturing data in the photodiodes, processing received data, interfacing with other circuitry, or the like. Additional layers on the front side of the assembled structure can subsequently be formed in some embodiments, such as passivating or planarizing layers. Figure 1 The support electronic components 106 of FIG. 1).

[0046] Figure 4OThe microlenses 302, 312, and 322 are shown coupled over the backside of the semiconductor substrate 310 for photodiodes, that is, each of the plurality of microlenses is coupled to the backside of the semiconductor substrate. Each microlens 302, 312, and 322 can be positioned over a corresponding photodiode associated with an implant region 304 or a different semiconductor material 324 and associated implant region 325. Further, each microlens 302, 312, and 322 is configured to direct (and possibly filter) received light (e.g., visible light 112 or IR light 114) downward to its corresponding sensing photodiode.

[0047] According to some embodiments, Figure 5 A method 500 is shown for forming a multi-band optical sensing IC. While this method and other methods shown and / or described herein are presented in the form of a series of operations or events, it is to be understood that the present application is not limited to the disclosed order or sequence of operations. Then, in some embodiments, the order of execution of the operations can be different than those depicted and / or described herein, and / or can occur at the same time. Further, in some embodiments, the illustrated operations or events can be sub-divided into additional operations or events, which are performed in separate time sequences or other behaviors or sub-behaviors are performed in the same time sequence. In some embodiments, some of the illustrated operations or events can be omitted, and other non-illustrated operations or events can be included.

[0048] For example, in some embodiments, operations 502-518 can correspond to the structure previously shown and described in Figures 4A to 4O At operation 502, a semiconductor substrate (e.g., semiconductor substrate 310) can be provided (e.g., as shown in Figure 4A At operation 504, a first dopant can be implanted by a first (e.g., frontside) surface of the semiconductor substrate to create a plurality of first light-absorbing regions (e.g., implant regions 304) in the semiconductor substrate for use by a first light band (e.g., a visible light band) (e.g., as shown in Figure 4B At operation 506, a set of gate structures (e.g., gate structures 332) can be formed on the first surface of the semiconductor substrate adjacent to a corresponding set of first light-absorbing regions (e.g., as shown in Figure 4C At operation 508, a plurality of cavities (e.g., cavities 323) can be etched in the first surface of the semiconductor substrate (e.g., as shown in Figure 4D At operation 510, the plurality of cavities can be filled with a semiconductor material different from the semiconductor substrate (e.g., different semiconductor material 324) (e.g., as shown in Figure 4EAt operation 512, a second dopant can be implanted in each cavity filled with a different semiconductor material to create a plurality of second light absorption regions (e.g., implant regions 325) in the semiconductor substrate for a second light wavelength band (e.g., an infrared light wavelength band) different from the first light wavelength band (e.g., as shown in FIG. 3B). Figure 4F At operation 514, an insulating structure (e.g., dielectric material 330) is formed over the first surface of the semiconductor substrate (e.g., as shown in FIG. 3C). Figure 4I , Figure 4K and 4M At operation 516, a plurality of connections (e.g., contact windows 336, metal structures 338 and 342, and via 340) is formed, each of the plurality of connections connecting from the insulating structure to a corresponding one of the plurality of gate structures, a plurality of second light absorption regions adjacent to locations of the plurality of gate structures on the semiconductor substrate (e.g., as shown in FIG. 3D). Figure 4H , Figure 4J , Figure 4L and Figure 4N At operation 518, a decision can be made whether to couple a plurality of microlenses (e.g., microlenses 302, 312, and 322) to a second (e.g., backside) surface of the semiconductor substrate (e.g., as shown in FIG. 3E). Figure 4O

[0049] Some embodiments of the present disclosure relate to integrated circuit light sensing devices. An integrated circuit light sensor includes a semiconductor substrate and a plurality of first light absorption regions and a plurality of second light absorption regions in the semiconductor substrate. Each first light absorption region includes an implant region of the semiconductor substrate, the implant region and the semiconductor substrate forming at least a portion of a corresponding set of first light detectors for a first light wavelength band; each second light absorption region includes a semiconductor material different from the semiconductor substrate, the semiconductor material forming at least a portion of a corresponding set of second light detectors for a second light wavelength band different from the first light wavelength band.

[0050] ​Some embodiments of the present application relate to integrated circuit light sensing devices. The integrated circuit light sensing device includes a substrate having a first side and a second side. The integrated circuit light sensing device also includes an interconnect device having a dielectric structure, a metal line, and a via disposed over the first side, and a plurality of first light absorption regions and a plurality of second light absorption regions disposed in the substrate. Each of the plurality of first light absorption regions includes a doped region of the substrate that, together with the substrate, forms at least a portion of a corresponding set of first light detectors for a first visible light band. Each of the plurality of second light absorption regions includes a germanium region that extends from the first side to a depth within the substrate, the germanium region forming at least a portion of a corresponding set of second light detectors for a second light band different from the first visible light band. The plurality of second light absorption regions are interspersed with the plurality of first light absorption regions in a plan view of the structure.

[0051] Some embodiments of the present application relate to methods of manufacturing integrated circuit light sensing devices. The method includes providing a semiconductor substrate and implanting a first dopant through a first surface of the semiconductor substrate to create a plurality of first light absorption regions in the semiconductor substrate for a first light band. The method also includes etching a plurality of cavities in the semiconductor substrate through the first surface of the semiconductor substrate and filling the plurality of cavities with a semiconductor material different from the semiconductor substrate. The method also includes implanting a second dopant into each set of the cavities filled with the semiconductor material to create a plurality of second light absorption regions in the semiconductor substrate for a second light band different from the first light band.

[0052] It is to be understood that the terms "first", "second", "third", and the like, used herein do not denote any order, quantity, or structure of the components, but are used to distinguish one or a series of components from another. For example, a "first dielectric layer" described in relation to a first figure can not correspond to a "first dielectric layer" described in relation to a second figure, and can not correspond to a "first dielectric layer" in an embodiment not shown.

[0053] The foregoing has outlined rather broadly the features of several embodiments in order that the detailed description can be better understood. Those skilled in the art will appreciate that they can readily use the present application as a basis for designing or modifying other processes and structures for carrying out the same purposes and / or achieving the same advantages of the embodiments introduced herein. Those skilled in the art will also appreciate that the present application can be used with a variety of alternative designs and embodiments without departing from the spirit and scope of the present application.

Claims

1. An integrated circuit light sensing device, comprising: a semiconductor substrate; a plurality of first light absorption regions in the semiconductor substrate, each of the plurality of first light absorption regions comprising an implanted region of the semiconductor substrate, the implanted region and the semiconductor substrate forming at least a portion of a set of first light detectors for a first light wavelength band; and a plurality of second light absorption regions in the semiconductor substrate, each of the plurality of second light absorption regions comprising a semiconductor material different from the semiconductor substrate and forming at least a portion of a set of second light detectors for a second light wavelength band different from the first light wavelength band. wherein:

2. The integrated circuit light sensor device of claim 1, wherein the plurality of first light detectors comprises a plurality of first photodiodes; and each of the plurality of first photodiodes comprises a photodiode interface defined by the semiconductor substrate and the implanted region of the first photodiode. further comprising:

3. The integrated circuit optical sensor device of claim 2, wherein a plurality of gate structures disposed on the semiconductor substrate, wherein each of the plurality of gate structures is adjacent to a location of a corresponding one of the plurality of first photodiodes; a plurality of first connections disposed on the semiconductor substrate, wherein each of the plurality of first connections is adjacent to a location of a corresponding one of the plurality of gate structures. wherein:

4. The integrated circuit light sensor device of claim 1, wherein the plurality of second light detectors comprises a plurality of second photodiodes; and each of the plurality of second photodiodes comprises a photodiode interface defined by the semiconductor material and an implanted region of the semiconductor material. further comprising:

5. The integrated circuit light sensor device of claim 4, wherein a plurality of anodes, wherein at least one of the plurality of anodes is disposed on the semiconductor material of each of the plurality of second photodiodes; a plurality of cathodes, wherein at least one of the plurality of cathodes is disposed on the implanted region of the semiconductor material of each of the plurality of second photodiodes. wherein, 6. The integrated circuit light sensor device of claim 1, wherein in a plan view of the semiconductor substrate, each of the plurality of first light detectors is adjacent to a corresponding one of the plurality of second light detectors. wherein, 7. The integrated circuit light sensor device of claim 1, wherein in a plan view of the semiconductor substrate: the plurality of first light detectors are organized as a two-dimensional array of a plurality of SWIR sub-pixel groups, each of the plurality of SWIR sub-pixel groups comprises four groups of the plurality of first light detectors in a first 2x2 configuration; and the plurality of second light detectors are organized as a two-dimensional array of a plurality of visible sub-pixel groups, each of the plurality of visible sub-pixel groups comprises four groups of the plurality of second light detectors in a second 2x2 configuration. wherein, 8. The integrated circuit optical sensor device of claim 7, wherein in a plan view: for each of the plurality of SWIR sub-pixel groups, each of the plurality of first light detectors is adjacent to the second light detectors of a corresponding one of the plurality of visible sub-pixel groups.

9. An integrated circuit light sensing device, comprising: a substrate, the substrate comprising a first side and a second side; an interconnect structure, the interconnect structure comprising a dielectric structure, metal lines, and vias disposed on the first side; ​ a plurality of first light-absorbing regions in the substrate, each of the plurality of first light-absorbing regions comprising a doped region of the substrate forming at least a portion of a corresponding one of a plurality of first photodetectors for a first visible light wavelength band; and a plurality of second light-absorbing regions in the substrate, each of the plurality of second light-absorbing regions comprising a region of germanium extending from the first side into the substrate to a depth and forming at least a portion of a corresponding one of a plurality of second photodetectors for a second light wavelength band different from the first visible light wavelength band; and wherein, in a plan view of the substrate, the plurality of second light-absorbing regions are interspersed with the plurality of first light-absorbing regions.

10. The integrated circuit light sensor device of claim 9, wherein further comprising: a plurality of microlenses, each of the plurality of microlenses being coupled to the second side of the substrate and, in a plan view of the substrate, aligned with a corresponding one of the plurality of first light-absorbing regions or a corresponding one of the plurality of second light-absorbing regions.

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