CN114112036A - Imaging chip, chip module and forming method thereof, electronic equipment and imaging method - Google Patents

Abstract

The application discloses multispectral imaging chip and forming method thereof, multispectral imaging module and forming method thereof, electronic equipment and imaging method thereof, the multispectral imaging chip comprises: the front surface of the optical sensing layer is provided with an optical sensing area, and a sensing array comprising a plurality of pixel units is formed in the optical sensing area; the optical structure layer comprises a substrate, an imaging structure and a spectrum channel layer, wherein the substrate is provided with a light transmission area corresponding to the optical sensing area, the imaging structure is positioned in the light transmission area, the spectrum channel layer corresponds to at least part of the optical sensing area and comprises at least one spectrum channel, and the spectrum channel is used for passing light rays of a specific waveband. The multispectral imaging chip can perform multispectral imaging.

Description

Imaging chip, chip module and forming method thereof, electronic equipment and imaging method

Technical Field

The application relates to the technical field of sensing, in particular to a multispectral imaging chip and a forming method thereof, a chip module and a forming method thereof, and electronic equipment and an imaging method thereof.

Background

The multispectral imaging technology is originated from geological mineral identification mapping research, is gradually expanded into the research of vegetation ecology, ocean coast water color, soil and atmosphere, and has very important significance in the fields of space detection, military safety, national and local resources, scientific research and the like. With the development of scientific technology, the multispectral imaging technology is increasingly in demand in the fields of machine vision, medical imaging, consumer electronics and security systems, accurate agriculture and forestry, artificial intelligence, military scientific research and the like.

The imaging spectrometer is an important research direction in remote sensing science, the remote sensing measurement of the earth can provide ground feature information which is difficult to obtain in ground observation, the number of channels recorded by multispectral imaging can reach hundreds, the spectral channels are narrow, the resolution ratio is high, the spectral detection range of the imaging spectrometer far exceeds the perception range of human eyes, a large amount of information which cannot be seen by human eyes can be detected, and the understanding of people on nature and substances is improved. Common multispectral imaging technologies include grating light splitting, acousto-optic tunable filter light splitting, prism light splitting, interference light splitting and the like, and the multiple spectral channels are used for transmitting relevant spectral characteristic information and are received by the sensor.

The multispectral sensor adopting the multispectral imaging has a plurality of camera structures, is relatively large in size, requires multiple exposures to obtain multispectral information in the using process, only has related information of a plurality of spectrums in the actually obtained information, and is relatively complex in spectrum information processing.

Recently, with the development of diversity of electronic device terminals, multispectral technology is also gradually applied to mobile terminal devices. However, the multispectral sensor applied in the above-mentioned applications generally has a large volume and a single function, and can only acquire different spectral information of an identified object, and does not have an imaging function, so that the multispectral sensor cannot be widely applied to consumer electronics.

Therefore, most consumer electronics can realize imaging function, but cannot perform multispectral imaging. Therefore, how to simultaneously realize multispectral detection and imaging is a problem to be solved urgently at present.

Disclosure of Invention

In view of this, the present disclosure provides a multispectral imaging chip and a forming method thereof, a multispectral imaging module and a forming method thereof, an electronic device and an imaging method thereof, so as to solve the problem that the conventional multispectral detection cannot perform imaging.

The specific implementation mode of the invention provides a multispectral imaging chip, which comprises: the front surface of the optical sensing layer is provided with an optical sensing area, and a sensing array comprising a plurality of pixel units is formed in the optical sensing area; the optical structure layer comprises a substrate, an imaging structure and a spectrum channel layer, wherein the substrate is provided with a light transmission area corresponding to the optical sensing area, the imaging structure is positioned in the light transmission area, the spectrum channel layer corresponds to at least part of the optical sensing area and comprises at least one spectrum channel, and the spectrum channel is used for passing light rays with a specific wave band.

Optionally, the substrate has a first surface and a second surface opposite to each other, the first surface faces the light entering direction, and the imaging structure is located on the first surface; the spectral channel layer is located on the second surface, or the spectral channel layer covers a surface of the imaging structure, or the spectral channel layer is located between the imaging structure and the substrate.

Optionally, each spectral channel corresponds to more than one pixel cell within the optical sensing area.

Optionally, the imaging structure comprises an array of lenses, a single lens of the array of lenses corresponding to one or more spectral channels.

Optionally, the spectrum channel corresponds to a plurality of pixel units located at the edge or the middle of the light sensing array, or the spectrum channel corresponds to the whole area where the light sensing array is located.

Optionally, the optical imaging structure layer is fixed above the optical sensing layer through a bonding layer; the bonding layer is arranged on the periphery of the optical sensing area and the light transmission area and is fixedly bonded with the optical structure layer and the optical sensing layer; or the optical structure layer and the optical sensing layer are fixed through a transparent bonding layer, and the transparent bonding layer covers the whole optical sensing layer.

Optionally, the optical sensing layer further includes an electrical connection structure electrically connected to the sensing array.

Optionally, the electrical connection structure includes: and the bonding pads are positioned on the front surface of the optical sensing layer or the welding bumps are positioned on the back surface of the optical sensing layer.

The technical scheme of the invention also provides a multispectral imaging module, which comprises: the multispectral imaging chip is arranged on the imaging chip; a circuit board; and an electric connection is formed between the electric connection structure of the optical sensing layer of the multispectral imaging chip and the circuit board.

Optionally, the electrical connection structure includes a solder bump located on the back surface of the optical sensing layer, and the multispectral imaging chip is flip-chip bonded to the surface of the circuit board through the solder bump.

Optionally, the electrical connection structure includes a pad located on the front surface of the optical sensing layer, and the pad and the circuit board are electrically connected through a bonding wire.

Optionally, the circuit board has an opening therein, and the multispectral imaging chip is located in the opening.

The technical scheme of the invention also provides a method for forming the multispectral imaging chip, which comprises the following steps: providing an optical sensing layer, wherein the front surface of the optical sensing layer is provided with an optical sensing area, and a sensing array comprising a plurality of pixel units is formed in the optical sensing area; forming an optical structure layer, wherein the optical structure layer comprises a substrate, an imaging structure and a spectrum channel layer, the substrate is provided with a light transmission area corresponding to the optical sensing area, the imaging structure is positioned in the light transmission area, the spectrum channel layer corresponds to at least part of the optical sensing area and comprises at least one spectrum channel, and the spectrum channel is used for passing light rays with a specific wave band; and fixing the substrate on the optical sensing layer so that the light-transmitting area is opposite to the optical sensing area.

Optionally, the substrate has a first surface and a second surface opposite to each other, the first surface faces a light entering direction, and the imaging structure is formed on the first surface.

Optionally, forming the spectral channel layer on the second surface before fixing the substrate on the optical sensing layer; or, forming the spectral channel layer on the surface of the imaging structure; alternatively, after the spectral channel layer is formed on the first surface, the imaging structure is formed on the spectral channel layer.

Optionally, the imaging structure comprises a lens array; individual lenses in the lens array correspond to one or more spectral channels.

Optionally, the method further includes: forming an electrical connection structure within the optical sensing layer that connects to the sensing array.

Optionally, the forming method of the electrical connection structure includes: forming a solder bump on the back of the optical sensing layer after fixing the substrate on the optical sensing layer, wherein the solder bump is electrically connected to the sensing array; alternatively, pads electrically connected to the sensing array are formed on the front surface of the optical sensing layer before the substrate is fixed to the optical sensing layer.

Optionally, after the solder bump is formed, the lens array is formed on the first surface of the substrate.

The technical scheme of the invention also provides a method for forming the multispectral imaging module, which comprises the following steps: providing a circuit board; and electrically connecting the electric connection structure of the optical sensing layer of the multispectral imaging chip to the circuit board.

Optionally, the method further includes: the electrical connection is formed by a wire bonding process or the optical sensing layer is flip-chip bonded to the circuit board by a flip-chip bonding process.

The technical solution of the present invention also provides an electronic device, including: providing the multispectral imaging module; and the processor is connected with the multispectral imaging module and is used for acquiring the induction signals generated by the pixel units corresponding to the spectral channels in the multispectral imaging module and forming a multispectral image.

Optionally, the processor is further configured to perform feature identification according to the sensing signal generated by the pixel unit corresponding to the specific spectral channel.

The technical scheme of the invention also provides a multispectral imaging method of electronic equipment, wherein the electronic equipment comprises the multispectral imaging module, and the multispectral imaging method comprises the following steps: and acquiring induction signals generated by pixel units corresponding to all spectral channels in the multispectral imaging module, and forming a multispectral image.

Optionally, the method further includes: and performing characteristic identification according to the sensing signals generated by the pixel units corresponding to the specific spectral channels.

The optical structure layer of the multispectral imaging chip comprises a multispectral channel layer, wherein the multispectral channel layer comprises at least one multispectral channel, and the multispectral channel layer is used for matching with the optical imaging structure design through light rays of a specific wave band, so that the information of multiple spectrums of an object and the surrounding environment and images under the specific spectrums can be acquired while single exposure is realized.

Drawings

In order to more clearly illustrate the technical solutions in the embodiments of the present application, the drawings needed to be used in the description of the embodiments are briefly introduced below, and it is obvious that the drawings in the following description are only some embodiments of the present application, and it is obvious for those skilled in the art to obtain other drawings based on these drawings without creative efforts.

Fig. 1 to 9 are schematic structural diagrams illustrating a process of forming a multispectral imaging chip according to an embodiment of the present invention;

FIG. 10 is a schematic structural diagram of a multispectral imaging module according to an embodiment of the present invention;

fig. 11 is a schematic structural diagram of a multispectral imaging module according to an embodiment of the present invention.

Detailed Description

As described in the background, multispectral imaging by mobile terminal devices is currently not possible. The embodiment of the invention provides a multispectral imaging chip which is small in size and can be suitable for multispectral imaging of mobile terminal equipment.

The technical solutions in the embodiments of the present application are clearly and completely described below with reference to the accompanying drawings, and it is obvious that the described embodiments are only a part of the embodiments of the present application, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present application. The following embodiments and their technical features may be combined with each other without conflict.

Fig. 1 to 9 show a method for forming a multispectral chip according to an embodiment of the invention.

Referring to fig. 1, an optical sensing layer 100 is provided.

The front surface of the optical sensing layer 100 is provided with an optical sensing area 101, and a sensing array comprising a plurality of pixel units is formed in the optical sensing area 101.

The optical sensing layer 100 has opposite front and back surfaces, and the optical sensing region 101 is located on the front surface of the optical sensing layer 100.

Specifically, as an embodiment, the optical sensing layer 100 includes a semiconductor substrate, and a dielectric layer formed on a top surface of the semiconductor substrate, where one side of the dielectric layer is a front surface, and one side of a bottom of the semiconductor substrate is a back surface. The sensing array in the optical sensing region 101 includes a plurality of pixel units, and the pixel units may be photosensitive sensing units such as CMOS sensing units or CCD sensing units formed on the semiconductor substrate, and are used for converting optical signals into electrical signals. In other embodiments, the optical sensing area 101 may further include a filter layer or the like on the pixel unit,

an interconnection structure, such as an interconnection line, connected to the pixel unit may be formed in the dielectric layer of the optical sensing layer 100. In some embodiments, pads may be formed on the front side of the optical sensing layer 100 to connect with interconnect structures within the dielectric layer. In some embodiments, the bonding pads may be formed at the periphery of the optical sensing region 101, and the bonding pads are connected with the interconnection structure in the optical sensing layer 100 to serve as connection points for signal output of the sensing array. In other embodiments, an electrical connection structure may be formed on the back surface of the optical sensing layer 100 in a subsequent process through a wafer level packaging process to output a sensing signal.

Although fig. 1 shows only a single chip structure, in an actual forming process, the optical sensing layer 100 may be a part of an entire wafer or a single bare chip obtained after dicing the wafer.

Referring to fig. 2, a substrate 200 is provided, the substrate 200 has a light-transmitting area corresponding to the optical sensing area 101, the substrate 200 has a first surface 201 and a second surface 202 opposite to each other, and the first surface 201 faces a light entering direction.

In this embodiment, the substrate 200 is made of glass. In some embodiments, the substrate 200 may also be made of transparent material such as plexiglass. In some embodiments, only a portion of the transparent region of the substrate corresponding to the light sensing region 101 may be made of a transparent material, and the other portion may be made of an opaque material.

Referring to fig. 3, the spectral channel layer 300 is formed on the second surface 202 of the substrate 200.

The spectral channel layer 300 is formed in the light-transmitting region of the substrate 200, and the spectral channel layer 300 includes at least one spectral channel for passing light of a specific wavelength band, and different types of spectral channels for passing light of different wavelength bands. The at least one spectral channel corresponds to at least a portion of the optical sensing region.

The spectral channels in the spectral channel layer 300 may be set as required, for example, corresponding spectral channels may be set for one or more of light rays in various specific bands, such as one or more colors of infrared light, ultraviolet light, and visible light, so as to obtain corresponding spectral information.

After the incident light passes through the spectral channel layer 300, the light with the corresponding specific wavelength can only pass through the positions of the various spectral channels, so that after being absorbed by the sensing array, the pixel units in the corresponding areas can only receive the light with the specific wavelength, and a multispectral image is finally formed.

In the case that multiple spectral channels exist, the sensing signals generated by the pixel units corresponding to the spectral channels may be processed, so that multiple spectral images corresponding to the spectral channels may be obtained, or the multispectral sensing signals may be presented in the same image.

Fig. 4a to 4c are schematic diagrams of a spectral channel layer 300 according to an embodiment of the invention.

Fig. 4a is a schematic diagram of each spectral channel in the spectral channel layer 300 according to an embodiment of the invention.

In this embodiment, the spectral channel layer 300 includes spectral channels corresponding to four wavelength bands of red, yellow, blue and green in visible light, which are a spectral channel 301, a spectral channel 302, a spectral channel 303 and a spectral channel 304.

The spectrum channels 301-304 are distributed in the whole light-transmitting area, and the spectrum channels are arranged at regular intervals in an array mode, so that the spectrum channels 301-304 correspond to the whole area where the light sensing array is located.

In this embodiment, after the incident light passes through the spectral channel layer 300, the light with the corresponding specific wavelength can only pass through the various spectral channel positions, so that after being absorbed by the sensor array, the pixel units in the corresponding region can only receive the light with the specific wavelength, thereby finally forming the multispectral image.

Fig. 4b is a schematic diagram of a spectral channel layer 300 according to another embodiment of the invention.

In this embodiment, the spectral channel layer 300 includes not only spectral channels for specific wavelength bands, but also transparent channels 305. In this embodiment, the spectrum channel layer 300 includes spectrum channels corresponding to four bands of red, yellow, blue and green in visible light, namely a spectrum channel 301, a spectrum channel 302, a spectrum channel 303 and a spectrum channel 304. The spectrum channels 301-304 are distributed at the edge of the light-transmitting area and correspond to a plurality of pixel units at the edge of the light sensing array.

Fig. 4c is a schematic diagram of a spectral channel layer 300 according to another embodiment of the invention.

In this embodiment, the spectral channel layer 300 includes a spectral channel 303 for blue light, a spectral channel 304 for green light, and a transparent channel 305 capable of transmitting all wavelength bands of light.

The spectral channels 303 and 304 are arranged in columns at intervals, and are formed in partial areas at the edges and the middle of the light-transmitting area so as to correspond to partial pixel units at corresponding positions in the optical sensing area.

The transparent channel 305 may be a transparent film, or the transparent channel 305 may be an opening without any film.

In other embodiments, there may be only one spectral channel, or three, four, or even more than five spectral channels in the spectral channel layer 300. Those skilled in the art can reasonably set the position distribution of each spectral channel and the specific wavelength band that each spectral channel can pass through according to specific needs.

The size of an individual spectral channel may be adjusted such that the size of an individual said spectral channel corresponds to one or more pixel elements.

The spectral channel layer 300 may be formed by depositing a spectral channel layer 300 having high transmittance to a specific wavelength band on the second surface of the substrate 200 by using evaporation or sputtering. The spectral channels in the spectral channel layer 300 for different bands may respectively adopt different film layer materials or structures. The multispectral film layer is manufactured by each spectral channel, and the multispectral structure can also be manufactured by other suitable methods; the film layers of the spectral channels can comprise at least one of an organic film layer, an inorganic film layer and a semiconductor material layer, and can also comprise at least one of functional layers such as an antireflection film layer, an antireflection layer, a hydrophobic layer and an oil drainage layer, and the film layers can be reasonably arranged according to specific needs.

In an embodiment of the present invention, a color filter array, such as a bayer array arranged in RGGB, or a color filter array in RYYB, RGBW, etc., may be formed on a pixel unit in the photo-sensing region 101 of the photo-sensing layer 100.

In some embodiments, the color and position distribution of the color filter array in the optical sensing region 101 may also be set according to the position and the corresponding wavelength band of each spectral channel in the multispectral channel layer 300. For example, an RGGB bayer filter array is disposed in an area where a pixel unit corresponding to the transparent channel 305 is located, and is used for imaging an RGB image; and filter layers are not required to be formed on the pixel units corresponding to other spectral channels of a specific waveband, and the received light waveband is limited only by the spectral channels. In other embodiments, filter layers with the same wavelength band transmission effect or filter layers with different wavelength band transmission effects may also be formed above the pixel units corresponding to the spectral channels, and the light finally received by the pixel units is the light transmitted after the spectral channels and the filter layers act together.

Referring to fig. 5, the substrate 200 is fixed on the optical sensing layer 100 such that the light-transmitting region of the substrate 200 is opposite to the optical sensing region 101.

The second surface 201 of the substrate 200 faces the front surface of the optical sensing layer 100, and the substrate 200 and the optical sensing layer 100 are bonded and fixed through a bonding layer 500.

In this embodiment, the bonding layer 500 is a non-transparent material layer, and the bonding layer 500 is disposed on the periphery of the optical sensing region 101 and the light-transmitting region to form an opening. The bonding layer 500 and the substrate 200 and the optical sensing layer 100 may be fixed by an adhesive, such that a cavity is formed between the bonding layer 500, the substrate 200 and the optical sensing layer 100, and the optical sensing layer 500 and the light-transmitting region are both facing the cavity. Light passing through the substrate 200 and the multispectral channel layer 300 passes through the cavity and impinges on the optical sensing area 101.

Fig. 6 is a schematic structural view illustrating the substrate 200 fixed on the optical sensing layer 100 according to another embodiment of the present invention.

In this embodiment, the substrate 200 and the optical sensing layer 100 are fixed by a transparent bonding layer 600. The transparent bonding layer 600 covers the entire optical sensing layer 100. The material of the transparent bonding layer 600 may be a transparent adhesive layer.

Referring to fig. 7, an electrical connection structure 700 connected to the sensing array is formed in the optical sensing layer 100.

In this embodiment, a wafer level packaging process is used to form an electrical connection structure on the back side of the optical sensing layer 100.

The electrical connection structure comprises an electrical connection line 701 and a soldering bump 702, and the soldering bump 702 is connected to the sensing array in the optical sensing region 101 through the electrical connection line 701. The solder bump 701 may be a solder ball or a metal stud.

In other embodiments, pads may also be formed on the front surface of the optical sensing layer 100, and the pads are electrically connected to the sensing array in the photo-sensing region 101. The bonding pads may be formed prior to attaching the optical structure layer to the front side of the photo-sensing layer 100.

Referring to fig. 8, a lens array 800 is formed on the first surface 201 of the substrate 200.

The lens array 800 includes a plurality of imaging lenses 801 arranged in an array, each lens 801 having a size corresponding to one or more spectral channels. The lens array 800 is formed on the light-transmitting region of the substrate 200.

The lens array may be formed by etching the first surface 201 of the substrate 200; or depositing a transparent material layer on the first surface 201 of the substrate 200 and etching the transparent material layer to form the lens array 800. In other embodiments, the lens array 800 may be formed by nanoimprinting or thermal reflow

A light-shielding layer 802 is formed on the peripheral region of the lens array 800 and the surface of the substrate 200 between the adjacent lenses 801.

To this end, the lens array 800, the substrate 200 and the multispectral channel layer 300 constitute optical structure layers. By properly setting the focal length of the lens 801 and the distance between the lens 801 and the optical sensing area 101, the optical sensing area 101 can be located in the focal plane of the lens array 800 for imaging.

In other embodiments, the lens array may be replaced by other imaging structures, such as collimating structures, gratings, or light-transmissive hole structures in the substrate 200.

Fig. 9 is a schematic structural diagram of a multispectral imaging module according to another embodiment of the present invention.

In this embodiment, the multispectral channel layer 300a within the optical structure layer is formed between the substrate 200 and the lens 801. Specifically, after the substrate 200 is fixed on the optical sensing layer 100, the multispectral channel layer 300a is formed on the first surface 201 of the substrate 200; the lens array 800 is then formed on the multi-spectral channel layer 300 a.

In other embodiments, the multispectral channel layer may also be formed on the surface of the lens 801.

The position of the multispectral channel layer can be set reasonably by those skilled in the art according to requirements.

Through the above embodiments, the multispectral imaging chip having the multispectral imaging function is formed.

Embodiments of the present invention further form a multi-spectral imaging module.

With continued reference to fig. 10, a circuit board 1002 is provided to electrically connect the electrical connection structure of the optical sensing layer 100 to the circuit board 1002.

In this embodiment, the circuit board 1002 is a flexible circuit board, and the circuit board 1002 is fixed on a substrate 1001, and a rigid support is provided by the substrate 1001. The substrate 1001 may be a rigid board, such as a steel plate, a plastic plate, a rigid circuit board, or the like.

The multispectral imaging chip is flip-chip bonded on the circuit board 1002, and is electrically connected with the circuit in the circuit board 1002 through the bonding bumps 702, so that the sensing signals generated by the sensing array in the optical sensing layer 100 are output to the circuit board 1002.

Referring to fig. 11, a schematic structural diagram of an optical sensing layer 100a electrically connected to the circuit board 1102 according to another embodiment of the present invention is shown.

In this embodiment, the circuit board 1102 has an opening 1103 that secures the circuit board 1101 to the substrate 1101, providing rigid support through the substrate 1101. A pad 102 connected with an optical sensing array is formed on the front surface of the optical sensing layer 100a, the multispectral sensing chip is disposed in the opening 1103, the back surface of the optical sensing layer 100a is fixed on the surface of the substrate 1101 through an adhesive layer, and the pad 102 and the circuit board 1102 are electrically connected through wire bonding.

Since the optical sensing layer 100a is located in the opening 1103, the thickness of the packaged multi-spectrum sensing module is low.

In other embodiments, the circuit board may not have an opening, and the optical sensing layer 100a may be directly stacked on the circuit board.

In the method for forming the multispectral imaging chip according to the embodiment, the multispectral channel layer is formed in the light transmitting area of the imaging structure layer, the multispectral channel layer comprises at least one multispectral channel, and an optical imaging structure design is matched, so that information of a plurality of continuous spectrums of an object and the surrounding environment and images under specific spectrums can be acquired while single exposure is realized.

The embodiment of the invention also provides a multispectral imaging chip.

Fig. 9 is a schematic diagram of a multispectral imaging chip according to the present invention.

In this embodiment, the multispectral imaging chip includes: an optical sensing layer 100 and an optical structural layer.

The front surface of the optical sensing layer 100 is provided with an optical sensing area 101, and a sensing array comprising a plurality of pixel units is formed in the optical sensing area 101;

the optical structure layer comprises a substrate 200, a lens array 800 and a spectrum channel layer 300, wherein the substrate 200 is provided with a light transmission area corresponding to the optical sensing area 101, the array formed by the lenses 801 is positioned in the light transmission area, the spectrum channel layer 300 corresponds to at least part of the optical sensing area 101 and comprises at least one spectrum channel, and the spectrum channel is used for passing light rays with different specific wave bands.

The substrate 200 has a first surface 201 and a second surface 202 which are opposite, the first surface 201 faces the light incoming direction, and the lens array 800 is positioned on the first surface 201; the spectral channel layer 300 is located on the second surface 202, facing the optical sensing region 101. In other embodiments, the spectral channel layer 300 may also cover the surface of the lens array 800, or the spectral channel layer 300 is located between the lens array 800 and the substrate 200.

Each spectral channel in the spectral channel layer 300 corresponds to more than one pixel cell in the optical sensing region 101. Please refer to fig. 4a to 4c, which are schematic diagrams illustrating the distribution of spectral channels in the spectral channel layer.

Referring to fig. 4a, in this embodiment, the spectral channel layer 300 includes spectral channels corresponding to four wavelength bands of visible light, namely, a spectral channel 301, a spectral channel 302, a spectral channel 303, and a spectral channel 304. The spectrum channels 301-304 are distributed in the whole light-transmitting area, and the spectrum channels are arranged in an array at regular intervals, so that the spectrum channels 301-304 correspond to the whole area where the light sensing array is located.

Referring to fig. 4b, in this embodiment, the spectral channel layer 300 includes not only spectral channels for specific wavelength bands, but also a transparent channel 305. In this embodiment, the spectrum channel layer 300 includes spectrum channels corresponding to four wavelength bands of red, yellow, blue and green in visible light, namely a spectrum channel 301, a spectrum channel 302, a spectrum channel 303 and a spectrum channel 304. The spectrum channels 301-304 are distributed at the edge of the light-transmitting area and correspond to a plurality of pixel units at the edge of the light sensing array.

Referring to fig. 4c, in this embodiment, the spectral channel layer 300 includes a spectral channel 303 for blue light, a spectral channel 304 for green light, and a transparent channel 305 capable of transmitting all wavelength bands of light.

The spectral channels 303 and 304 are arranged in columns at intervals, and are formed in partial areas at the edges and the middle of the light-transmitting area so as to correspond to partial pixel units at corresponding positions in the optical sensing area. The transparent channel 305 may be a transparent film, or the transparent channel 305 may be an opening without any film.

In other embodiments, there may be only one spectral channel, or three, four, or even more than five spectral channels in the spectral channel layer 300. Those skilled in the art can reasonably set the position distribution of each spectral channel and the specific wavelength band that each spectral channel can pass through according to specific needs.

The spectral channels in the spectral channel layer 300 for different bands may respectively adopt different film layer materials or structures. The multispectral film layer is manufactured by each spectral channel, and the multispectral structure can also be manufactured by other suitable methods; the film layers of the spectral channels can comprise at least one of an organic film layer, an inorganic film layer and a semiconductor material layer, and can also comprise at least one of functional layers such as an antireflection film layer, an antireflection layer, a hydrophobic layer and an oil drainage layer, and the film layers can be reasonably arranged according to specific needs.

In some embodiments, a single lens 801 may correspond to one or more spectral channels.

In other examples, the lens array 800 may be replaced by other imaging structures located in the light-transmissive region, such as a collimating structure, a grating, or a light-transmissive hole structure in the substrate 200.

The optical structure layer is fixed above the optical sensing layer 100 through a bonding layer 500. In this embodiment, the bonding layer 500 is disposed on the periphery of the optical sensing region 101 and the light-transmitting region, and is bonded and fixed with the optical structure layer and the optical sensing layer 100.

In another embodiment, referring to fig. 6, the optical structure layer and the optical sensing layer 100 are fixed by a transparent bonding layer 600, and the transparent bonding layer 600 covers the entire optical sensing layer 100. The material of the transparent bonding layer 600 may be a transparent adhesive layer.

The optical sensing layer 100 also includes electrical connection structures that electrically connect to the sensing array within the optical sensing region 101. In this embodiment, the electrical connection structure includes: electrical connection lines 701 and solder bumps 702, the solder bumps 702 being connected to the sensing array in the photo-sensing region 101 through the electrical connection lines 701. The solder bumps 701 may be solder balls or metal bumps.

In other embodiments, the electrical connection structure of the optical sensing layer 100 includes: and the bonding pad is positioned on the front surface of the optical sensing layer.

The multispectral imaging chip further comprises: a circuit board 1002; an electrical connection is formed between the electrical connection structure of the optical sensing layer 100 and the circuit board 1002.

Referring to fig. 10, in this embodiment, the circuit board 1002 is a flexible circuit board, and the circuit board 1002 is fixed on a substrate 1001, and the substrate 1001 provides a rigid support. The substrate 1001 may be a rigid board, such as a steel plate, a plastic plate, a rigid circuit board, or the like. The multispectral imaging chip is flip-chip bonded on the circuit board 1002 and is electrically connected with the circuit in the circuit board 1002 through the bonding bumps 702, so that the sensing signals generated by the sensing array in the optical sensing layer 100 are output to the circuit board 1002.

Referring to fig. 11, in this embodiment, the circuit board 1102 has an opening 1103 to fix the circuit board 1101 on the substrate 1101, and the substrate 1101 provides a rigid support. A pad 102 connected with an optical sensing array is formed on the front surface of the optical sensing layer 100a, the multispectral sensing chip is disposed in the opening 1103, the back surface of the optical sensing layer 100a is fixed on the surface of the substrate 1101 through an adhesive layer and the like, and the pad 102 and the circuit board 1102 are electrically connected through wire bonding. Since the optical sensing layer 100a is located in the opening 1103, the thickness of the packaged multispectral sensing chip is low.

In other embodiments, the optical sensing layer 100a can be directly stacked on the circuit board 1102.

The embodiment of the invention further provides electronic equipment comprising the multispectral imaging module in any embodiment.

The electronic equipment further comprises a processor which is connected with the multispectral imaging module and is used for being matched with the multispectral imaging module to carry out multispectral imaging. The multispectral imaging method comprises the following steps: and acquiring sensing signals generated by pixel units corresponding to all spectral channels in the multispectral imaging module, and forming a multispectral image.

The signals of different spectrums can be processed independently, and a plurality of spectrum images are formed respectively aiming at the spectrums of different wave bands; it is also possible to combine images of multiple spectra in one image. Under the condition that a multispectral channel layer of the multispectral imaging module comprises a transparent channel, the multispectral image can be a composite image of RGB and a spectral image. For example, the multispectral image may be a composite image of an RGB image and an infrared image. Because the reflected light on the surface of the object has different characteristics due to the structural material characteristics of the surface of the object and the emitted light with different wave bands, the multispectral image obtained by the multispectral imaging chip can comprise image information in different spectral wave band ranges, and therefore, the detailed structure of the surface of the object to be shot can be embodied.

Furthermore, images of various spectrums can be synthesized through processing of software algorithms to obtain more detailed images with higher resolution, so that more accurate data can be obtained in the aspects of biological identification, detection of the surface and internal structures of organs in the medical field, quality detection of food and medicines and the like.

In some embodiments, the processor is further configured to perform feature identification according to the sensing signal generated by the pixel unit corresponding to the specific spectral channel.

The feature identification method comprises the following steps: obtaining characteristic information of the reflected light of the specific spectrum for comparison, and obtaining characteristic parameters; and carrying out feature recognition on the shot object according to the feature parameters.

In one embodiment, the authenticity of the photographed object can be identified by obtaining characteristic information of the object surface, such as light intensity and brightness of reflected light of a specific spectrum, and comparing the characteristic information. For example, because the reflection spectrum characteristics of different materials are different, the ratio of the intensity of the reflected light of two or more spectra can be selected as the characteristic parameter to distinguish and identify the true and false object materials.

That is, the above description is only an embodiment of the present application, and not intended to limit the scope of the present application, and all equivalent structures or equivalent flow transformations made by using the contents of the specification and the drawings, such as mutual combination of technical features between various embodiments, or direct or indirect application to other related technical fields, are included in the scope of the present application.

Claims (25)

1. A multispectral imaging chip, comprising:

the front surface of the optical sensing layer is provided with an optical sensing area, and a sensing array comprising a plurality of pixel units is formed in the optical sensing area;

the optical structure layer comprises a substrate, an imaging structure and a spectrum channel layer, wherein the substrate is provided with a light transmission area corresponding to the optical sensing area, the imaging structure is positioned in the light transmission area, the spectrum channel layer corresponds to at least part of the optical sensing area and comprises at least one spectrum channel, and the spectrum channel is used for passing light rays of a specific waveband.

2. The multispectral imaging chip of claim 1, wherein the substrate has first and second opposing surfaces, the first surface facing in a light entrance direction, the imaging structure being located on the first surface; the spectral channel layer is located on the second surface, or the spectral channel layer covers a surface of the imaging structure, or the spectral channel layer is located between the imaging structure and the substrate.

3. The multispectral imaging chip of claim 1, wherein each spectral channel corresponds to more than one pixel cell within the optical sensing region.

4. The multispectral imaging chip of claim 1, wherein the imaging structure comprises a lens array; individual lenses in the lens array correspond to one or more spectral channels.

5. The multispectral imaging chip of claim 1, wherein the spectral channels correspond to pixel elements located at an edge or a middle of the light sensing array, or the spectral channels correspond to an entire area where the light sensing array is located.

6. The multispectral imaging chip of claim 1, wherein the optical structure layer is secured over the optical sensing layer by a bonding layer; the bonding layer is arranged on the periphery of the optical sensing area and the light transmission area and is fixedly bonded with the optical structure layer and the optical sensing layer; or the optical structure layer and the optical sensing layer are fixed through a transparent bonding layer, and the transparent bonding layer covers the whole optical sensing layer.

7. The multispectral imaging chip of any one of claims 1 to 6, wherein the optical sensing layer further comprises an electrical connection structure electrically connected to the sensing array.

8. The multispectral imaging chip of claim 7, wherein the electrical connection structure comprises: and the bonding pads are positioned on the front surface of the optical sensing layer or the welding bumps are positioned on the back surface of the optical sensing layer.

9. A multi-spectral imaging module, comprising:

the multispectral imaging chip of claim 7;

a circuit board;

and an electric connection is formed between the electric connection structure of the optical sensing layer of the multispectral imaging chip and the circuit board.

10. The multispectral imaging module of claim 9, wherein the electrical connection structure comprises a solder bump on a back surface of the optical sensing layer, and the multispectral imaging chip is flip-chip bonded to the surface of the circuit board via the solder bump.

11. The multispectral imaging module of claim 9, wherein the electrical connection structure comprises a bonding pad on the front side of the optical sensing layer, the bonding pad being electrically connected to the circuit board by a bonding wire.

12. The multispectral imaging module of claim 11, wherein the circuit board has an opening therein, and the multispectral imaging chip is located in the opening.

13. A method for forming a multispectral imaging chip is characterized by comprising the following steps:

providing an optical sensing layer, wherein the front surface of the optical sensing layer is provided with an optical sensing area, and a sensing array comprising a plurality of pixel units is formed in the optical sensing area;

forming an optical structure layer, wherein the optical structure layer comprises a substrate, an imaging structure and a spectrum channel layer, the substrate is provided with a light transmission area corresponding to the optical sensing area, the imaging structure is positioned in the light transmission area, the spectrum channel layer corresponds to at least part of the optical sensing area and comprises at least one spectrum channel, and the spectrum channel is used for passing light rays with a specific wave band;

and fixing the substrate on the optical sensing layer so that the light-transmitting area is opposite to the optical sensing area.

14. The method of claim 13 wherein said substrate has first and second opposing surfaces, said first surface facing in a light entrance direction, said imaging structure formed on said first surface.

15. The method for forming the multispectral imaging chip as recited in claim 13, wherein the spectral channel layer is formed on the second surface before the substrate is fixed on the optical sensing layer; or, forming the spectral channel layer on the surface of the imaging structure; alternatively, after the spectral channel layer is formed on the first surface, the imaging structure is formed on the spectral channel layer.

16. The method for forming the multispectral imaging chip as recited in claim 13, wherein the imaging structure comprises a lens array; individual lenses in the lens array correspond to one or more spectral channels.

17. The method for forming the multispectral imaging chip according to any one of claims 13 to 16, further comprising: forming an electrical connection structure within the optical sensing layer that connects to the sensing array.

18. The method for forming the multispectral imaging chip as recited in claim 17, wherein the method for forming the electrical connection structure comprises: forming solder bumps on the back of the optical sensing layer to be electrically connected to the sensing array after the substrate is fixed on the optical sensing layer; alternatively, pads electrically connected to the sensing array are formed on the front surface of the optical sensing layer before the substrate is fixed to the optical sensing layer.

19. The method for forming the multispectral imaging chip as recited in claim 18, wherein the lens array is formed on the first surface of the substrate after the solder bumps are formed.

20. A method for forming a multi-spectral imaging module, comprising:

providing the multispectral imaging chip according to claim 7 or formed by the method according to claim 17;

providing a circuit board;

and electrically connecting the electric connection structure of the optical sensing layer of the multispectral imaging chip to the circuit board.

21. The method of forming a multi-spectral imaging module of claim 20, comprising: the electrical connection is formed by a wire bonding process or the optical sensing layer is flip-chip bonded to the circuit board by a flip-chip bonding process.

22. An electronic device, comprising:

the multispectral imaging module of any one of claims 9 to 12;

and the processor is connected with the multispectral imaging module and is used for acquiring sensing signals generated by the pixel units corresponding to the spectral channels in the multispectral imaging module and forming a multispectral image.

23. The electronic device of claim 22, wherein the processor is further configured to perform feature recognition according to the sensing signal generated by the pixel unit corresponding to the specific spectral channel.

24. A method of multispectral imaging of an electronic device comprising the multispectral imaging module of any one of claims 9 to 12, the method comprising:

and acquiring induction signals generated by pixel units corresponding to all spectral channels in the multispectral imaging module, and forming a multispectral image.

25. The method of multispectral imaging according to claim 24, further comprising: and performing characteristic identification according to the sensing signals generated by the pixel units corresponding to the specific spectral channels.

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