WO2020244082A1

WO2020244082A1 - Optical fingerprint apparatus and manufacturing method therefor, and electronic device

Info

Publication number: WO2020244082A1
Application number: PCT/CN2019/104801
Authority: WO
Inventors: 吴宝全; 高攀
Original assignee: 深圳市汇顶科技股份有限公司
Priority date: 2019-06-05
Filing date: 2019-09-06
Publication date: 2020-12-10
Also published as: CN111247524A; CN111247524B

Abstract

An optical fingerprint apparatus and a manufacturing method therefor, and an electronic device. The optical fingerprint apparatus comprises: a filter (309) used for filtering out an optical signal of a non-target waveband and transmitting an optical signal of a target waveband; an optical path guiding structure (303) provided below the filter (309) and used for guiding, to an optical fingerprint chip (307), an optical signal which is returned after being reflected or scattered by a finger; the optical fingerprint chip (307) provided below the optical path guiding structure (303), the optical fingerprint chip (307) comprising a first pad (313) and a conductive through-hole structure; and a rewiring layer (311) provided below the optical fingerprint chip (307), the rewiring layer (311) comprising a second pad. The filter (309) is flush with the optical fingerprint chip (307) in a vertical direction, the first pad (313) is arranged on an upper surface of the optical fingerprint chip (307), and the conductive through-hole structure is arranged inside the optical fingerprint chip (307) and in communication with the first pad (313) and the second pad.

Description

Optical fingerprint device, manufacturing method and electronic equipment

This application claims the priority of the international application filed with the International Bureau on June 5, 2019 with the application number PCT/CN2019/090171 and the title of the invention "optical fingerprint device and electronic equipment", the entire content of which is incorporated into this application by reference in.

Technical field

The embodiments of the present application relate to the field of optical fingerprint technology, and more specifically, to an optical fingerprint device, a manufacturing method, and electronic equipment.

Background technique

With the advent of the era of full-screen mobile phones, under-screen fingerprint identification devices have become more and more widely used, and under-screen optical fingerprint identification devices are the most popular.

However, the size and area of current optical fingerprint devices are generally large, resulting in high production costs of optical fingerprint devices. Therefore, how to reduce the production cost of the optical fingerprint device is an urgent technical problem to be solved.

Summary of the invention

The embodiments of the present application provide an optical fingerprint device, a manufacturing method, and electronic equipment, which can effectively reduce the production cost of the optical fingerprint device.

In the first aspect, an optical fingerprint device is provided, including:

The filter is used to filter out the optical signal of the non-target waveband and pass the optical signal of the target waveband;

The optical path guiding structure is arranged under the optical filter, and is used to guide the optical signal returned from the reflection or scattering of the finger to the optical fingerprint chip;

The optical fingerprint chip is disposed under the optical path guiding structure, and the optical fingerprint chip includes a first pad and a conductive via structure located under the first pad;

The redistribution layer is arranged under the optical fingerprint chip, and the redistribution layer includes a second pad;

Wherein, the filter and the optical fingerprint chip are flush in the vertical direction, the first pad is arranged on the upper surface of the optical fingerprint chip, and the conductive via structure is arranged on the optical fingerprint chip It is internally connected with the first pad and the second pad.

In some possible embodiments, the optical fingerprint device further includes: a flexible circuit board arranged under the redistribution layer; wherein the optical filter and the optical fingerprint chip are integrally cut and arranged on the flexible circuit board. Above the circuit board.

In some possible embodiments, the optical fingerprint device further includes: an electrical connection layer disposed between the rewiring layer and the flexible circuit board, and the rewiring layer is connected to the flexible circuit board through the electrical connection layer. The flexible circuit board is electrically connected to transmit the electrical signal obtained by the optical fingerprint chip conversion to the flexible circuit board.

In some possible embodiments, the electrical connection layer is an anisotropic conductive adhesive ACF layer or a surface mount process SMT solder.

In some possible embodiments, the area of the filter is the same as the area of the optical fingerprint chip.

In some possible embodiments, the optical fingerprint device further includes: a transparent optical adhesive layer, which is disposed between the filter and the light path guiding structure, and is used to bond the filter and the light path. Guide structure.

In some possible embodiments, the light path guiding structure includes a microlens array, and the transparent optical glue layer is disposed between the filter and the microlens array, and/or is disposed on the filter. Between the sheet and the non-microlens array in the optical path guiding structure.

In some possible embodiments, the transparent optical adhesive layer is provided at least partly above the microlens array, and/or the transparent optical adhesive layer is provided at least partly above the non-microlens array .

In some possible embodiments, the refractive index of the transparent optical adhesive layer is lower than the refractive index of the microlens array.

In some possible embodiments, the microlens array includes a plurality of microlens units, and the optical fingerprint chip includes a plurality of pixel units; wherein, the first microlens unit of the plurality of microlens units is used to The first light signal from above the first microlens unit is converged to a first pixel unit corresponding to the first microlens unit among the plurality of pixel units.

In some possible embodiments, the rewiring layer is electrically isolated from the optical fingerprint chip by a first insulating layer.

In some possible embodiments, a second insulating layer is arranged between the lines of the redistribution layer.

In some possible embodiments, the conductive via structure includes the second insulating layer, the rewiring layer, and the first insulating layer.

In some possible embodiments, a coating layer is provided on the upper surface and/or the lower surface of the filter.

In some possible embodiments, the coating layer on the upper surface of the filter is used to cut off wavelengths shorter than 400 nm, and/or the coating on the lower surface of the filter is used to cut off wavelengths longer than 600 nm.

In some possible embodiments, the optical fingerprint device further includes: a coating layer for absorbing light of a specific wavelength band.

In some possible embodiments, the specific wavelength band is 570nm-700nm.

In some possible embodiments, the absorption rate of the coating layer for absorbing light of the specific wavelength band is greater than or equal to 80%.

In some possible embodiments, the coating layer is disposed between the filter and the coating layer on the upper surface of the filter, and/or the coating layer is disposed on the filter And the coating layer on the lower surface of the filter.

In some possible embodiments, the coating layer is disposed under the light path guiding structure.

In a second aspect, a manufacturing method of an optical fingerprint device is provided, the method including:

The optical filter, the optical path guiding structure, the optical fingerprint chip wafer, and the redistribution layer are bonded into one body. The optical filter is used to filter out the optical signal of the non-target wavelength band and transmit the optical signal of the target wavelength band. The optical path guiding structure is disposed under the optical filter, and is used to guide the optical signal reflected or scattered from the finger to the optical fingerprint chip wafer, and the optical fingerprint chip wafer is disposed on the optical path guiding structure Below, the redistribution layer is arranged under the optical fingerprint chip;

Thinning the optical fingerprint chip wafer;

Perform TSV processing on the back of the optical fingerprint chip wafer to form a conductive via structure inside the optical fingerprint chip wafer, and the conductive via structure communicates with the first optical fingerprint chip wafer A bonding pad and a second bonding pad of the rewiring layer;

The optical filter, the optical path guiding structure, the optical fingerprint chip wafer, and the redistribution layer are integrally cut.

In some possible embodiments, the manufacturing method further includes: integrally cutting the filter, the optical path guiding structure, the optical fingerprint chip wafer, and the redistribution layer and then connecting them to the top of the flexible circuit board.

In some possible embodiments, the step of integrally cutting the filter, the optical path guiding structure, the optical fingerprint chip wafer, and the redistribution layer and then connecting them to the top of the flexible circuit board includes: connecting the filter, After the optical path guiding structure, the optical fingerprint chip wafer, and the redistribution layer are cut in one piece, they are connected to the top of the flexible circuit board through the electrical connection layer to transmit the electrical signals obtained by the optical fingerprint chip wafer conversion to the flexible circuit board .

In some possible embodiments, the manufacturing method further includes: adhering the filter and the light path guiding structure through a transparent optical adhesive layer.

In some possible embodiments, the optical path guiding structure includes a microlens array, and the optical filter and the optical path guiding structure are bonded through a transparent optical glue layer, including: The microlens arrays are bonded through the transparent optical adhesive layer, and/or the transparent optical adhesive layer is bonded between the filter and the non-microlens array in the light path guiding structure .

In some possible embodiments, the transparent optical glue layer is disposed at least partly above the microlens array, and/or the transparent optical glue layer is disposed at least partly above the non-microlens array .

In some possible embodiments, the micro lens array includes a plurality of micro lens units, and the optical fingerprint chip wafer includes a plurality of pixel units; wherein, the first micro lens unit of the plurality of micro lens units is used Converging the first light signal from above the first microlens unit to a first pixel unit corresponding to the first microlens unit among the plurality of pixel units.

In some possible embodiments, the manufacturing method further includes: fabricating a first insulating layer between the redistribution layer and the optical fingerprint chip wafer, so as to connect the redistribution layer and the optical fingerprint chip wafer. Electrical isolation between wafers.

In some possible embodiments, the manufacturing method further includes: manufacturing a second insulating layer between the redistribution layer lines.

In some possible embodiments, the manufacturing method further includes: filling the second insulating layer, the redistribution layer, and the first insulating layer in the conductive via structure.

In some possible embodiments, before bonding the filter, the optical path guiding structure, the optical fingerprint chip wafer, and the redistribution layer into one body, the manufacturing method further includes: placing the filter on the upper surface and / Or make a coating layer on the lower surface.

In some possible embodiments, the manufacturing method further includes: manufacturing a coating layer for absorbing light in a specific wavelength band.

In some possible embodiments, the specific wavelength band is 570nm-700nm.

In some possible embodiments, the making the coating layer includes: making the coating layer between the filter and the coating layer on the upper surface of the filter, and/or, in the The coating layer is formed between the filter and the coating layer on the lower surface of the filter.

In some possible embodiments, the fabricating the coating layer includes: fabricating the coating layer under the light path guiding structure.

In a third aspect, an electronic device is provided, including a display screen and the first aspect or the optical fingerprint device in any possible implementation of the first aspect.

In the above technical solution, the optical fingerprint chip is packaged through the TSV process, that is, the filter and the optical fingerprint chip are bonded together and then cut together. Therefore, the filter has the same size and area as the optical fingerprint chip, which reduces the filter The area of the light sheet can effectively reduce the production cost of the optical fingerprint device.

Description of the drawings

FIG. 1 is a schematic structural diagram of an electronic device to which an embodiment of the present application is applied.

Figure 2 is a schematic diagram of an optical fingerprint gold threading module.

Fig. 3 is a schematic diagram of an optical fingerprint device according to an embodiment of the present application.

FIG. 4 is a processing flowchart of the TSV packaging process according to an embodiment of the present application.

Fig. 5 is a schematic diagram of an optical fingerprint device according to an embodiment of the present application.

Fig. 6 is a schematic flow chart of a manufacturing method of an optical fingerprint device according to an embodiment of the present application.

Fig. 7 is a schematic block diagram of an electronic device according to an embodiment of the present application.

Detailed ways

The technical solutions in the embodiments of the present application will be described below in conjunction with the drawings.

It should be understood that the embodiments of this application can be applied to optical fingerprint systems, including but not limited to optical fingerprint identification systems and medical diagnostic products based on optical fingerprint imaging. The embodiments of this application only take optical fingerprint systems as an example for description, but should not The embodiments of the application constitute any limitation, and the embodiments of the present application are also applicable to other systems using optical imaging technology.

As a common application scenario, the optical fingerprint system provided in the embodiments of this application can be applied to smart phones, tablet computers, and other mobile terminals with display screens or other terminal devices; more specifically, in the above-mentioned terminal devices, fingerprint identification The device may specifically be an optical fingerprint device, which may be arranged in a partial area or an entire area under the display screen, thereby forming an under-display optical fingerprint system. Alternatively, the fingerprint identification device can also be partially or fully integrated into the display screen of the terminal device, thereby forming an in-display optical fingerprint system.

As shown in FIG. 1 is a schematic structural diagram of a terminal device to which the embodiment of the application can be applied. The terminal device 10 includes a display screen 120 and an optical fingerprint device 130, wherein the optical fingerprint device 130 is disposed under the display screen 120 Local area. The optical fingerprint device 130 includes an optical fingerprint sensor, and the optical fingerprint sensor includes a sensing array 133 having a plurality of optical sensing units 131, and the area where the sensing array is located or its sensing area is the fingerprint detection area of the optical fingerprint device 130 103. As shown in FIG. 1, the fingerprint detection area 103 is located in the display area of the display screen 120. In an alternative embodiment, the optical fingerprint device 130 may also be arranged in other positions, such as the side of the display screen 120 or the non-transparent area of the edge of the terminal device 10, and the optical fingerprint device 130 may be designed to The optical signal of at least a part of the display area of the display screen 120 is guided to the optical fingerprint device 130, so that the fingerprint detection area 103 is actually located in the display area of the display screen 120.

It should be understood that the area of the fingerprint detection area 103 may be different from the area of the sensing array of the optical fingerprint device 130, for example, through optical path design such as lens imaging, reflective folding optical path design, or other optical path design such as light convergence or reflection, etc. The area of the fingerprint detection area 103 of the optical fingerprint device 130 can be made larger than the area of the sensing array of the optical fingerprint device 130. In other alternative implementations, if for example, light collimation is used for light path guidance, the fingerprint detection area 103 of the optical fingerprint device 130 may also be designed to be substantially the same as the area of the sensing array of the optical fingerprint device 130.

Therefore, when the user needs to unlock the terminal device or perform other fingerprint verification, he only needs to press his finger on the fingerprint detection area 103 located in the display screen 120 to realize fingerprint input. Since fingerprint detection can be implemented in the screen, the terminal device 10 adopting the above structure does not need to reserve a space on the front side for the fingerprint button (such as the Home button), so that a full screen solution can be adopted, that is, the display area of the display screen 120 It can be basically extended to the front of the entire terminal device 10.

As an optional implementation, as shown in FIG. 1, the optical fingerprint device 130 includes a light detecting part 134 and an optical component 132, and the light detecting part 134 includes the sensor array and is electrically connected to the sensor array. The connected reading circuit and other auxiliary circuits can be fabricated on a chip (Die) by a semiconductor process, such as an optical imaging chip or an optical fingerprint sensor. The sensing array is specifically a photodetector (Photodetector) array, which includes multiple There are two photodetectors distributed in an array, and the photodetectors can be used as the above-mentioned optical sensing unit.

The optical component 132 may be disposed above the sensing array of the light detecting part 134, which may specifically include a filter layer (Filter), a light guide layer or a light path guiding structure, and other optical elements. The filter layer may be used In order to filter out the ambient light penetrating the finger, the light guide layer or light path guiding structure is mainly used to guide the reflected light reflected from the finger surface to the sensor array for optical detection.

In terms of specific implementation, the optical assembly 132 and the light detecting part 134 may be packaged in the same optical fingerprint component. For example, the optical component 132 and the optical detection part 134 can be packaged in the same optical fingerprint chip, or the optical component 132 can be arranged outside the chip where the optical detection part 134 is located, for example, the optical component 132 is attached above the chip, or some components of the optical assembly 132 are integrated into the chip.

Wherein, the light guide layer or light path guiding structure of the optical component 132 has multiple implementation schemes. For example, the light guide layer may specifically be a collimator layer made on a semiconductor silicon wafer, which has multiple A collimating unit or a micro-hole array. The collimating unit can be specifically a small hole. Among the reflected light reflected from the finger, the light that is perpendicularly incident on the collimating unit can pass through and be passed by the optical sensing unit below it. The light with an excessively large incident angle is attenuated by multiple reflections inside the collimating unit. Therefore, each optical sensing unit can basically only receive the reflected light reflected by the fingerprint pattern directly above it. The sensor array can detect the fingerprint image of the finger.

In another embodiment, the light guide layer or the light path guide structure may also be an optical lens (Lens) layer, which has one or more lens units, such as a lens group composed of one or more aspheric lenses, which The sensing array used to converge the reflected light reflected from the finger to the light detection part 134 below it, so that the sensing array can perform imaging based on the reflected light, thereby obtaining a fingerprint image of the finger. Optionally, the optical lens layer may further have a pinhole formed in the optical path of the lens unit, and the pinhole may cooperate with the optical lens layer to expand the field of view of the optical fingerprint device to improve the optical The fingerprint imaging effect of the fingerprint device 130.

In other embodiments, the light guide layer or the light path guide structure may also specifically adopt a micro-lens (Micro-Lens) layer. The micro-lens layer has a micro-lens array formed by a plurality of micro-lenses, which can be grown by semiconductors. A process or other processes are formed above the sensing array of the light detecting part 134, and each microlens may correspond to one of the sensing units of the sensing array. Moreover, other optical film layers may be formed between the microlens layer and the sensing unit, such as a dielectric layer or a passivation layer. More specifically, the microlens layer and the sensing unit may also include The light-blocking layer of the micro-hole, wherein the micro-hole is formed between the corresponding micro-lens and the sensing unit, the light-blocking layer can block the optical interference between the adjacent micro-lens and the sensing unit, and make the sensing The light corresponding to the unit is condensed into the microhole through the microlens and is transmitted to the sensing unit through the microhole to perform optical fingerprint imaging.

It should be understood that several implementation solutions of the above-mentioned optical path guiding structure can be used alone or in combination. For example, a microlens layer can be further provided under the collimator layer or the optical lens layer. Of course, when the collimator layer or the optical lens layer is used in combination with the micro lens layer, its specific laminated structure or optical path may need to be adjusted according to actual needs.

As an optional embodiment, the display screen 120 may be a display screen with a self-luminous display unit, such as an organic light-emitting diode (Organic Light-Emitting Diode, OLED) display or a micro-LED (Micro-LED) display Screen. Taking an OLED display screen as an example, the optical fingerprint device 130 may use the display unit (ie, an OLED light source) of the OLED display screen 120 located in the fingerprint detection area 103 as an excitation light source for optical fingerprint detection. When the finger 140 is pressed against the fingerprint detection area 103, the display screen 120 emits a beam of light 111 to the target finger 140 above the fingerprint detection area 103. The light 111 is reflected on the surface of the finger 140 to form reflected light or pass through all the fingers. The finger 140 scatters to form scattered light. In related patent applications, for ease of description, the above-mentioned reflected light and scattered light are collectively referred to as reflected light. Because fingerprint ridges and valleys have different light reflection capabilities, the reflected light 151 from the fingerprint ridge and the reflected light 152 from the fingerprint ridge have different light intensities. After the reflected light passes through the optical component 132, It is received by the sensor array 134 in the optical fingerprint device 130 and converted into a corresponding electrical signal, that is, a fingerprint detection signal; based on the fingerprint detection signal, fingerprint image data can be obtained, and fingerprint matching verification can be further performed, so that the The terminal device 10 implements an optical fingerprint recognition function.

In other embodiments, the optical fingerprint device 130 may also use a built-in light source or an external light source to provide an optical signal for fingerprint detection. In this case, the optical fingerprint device 130 may be suitable for non-self-luminous display screens, such as liquid crystal display screens or other passively-luminous display screens. Taking a liquid crystal display with a backlight module and a liquid crystal panel as an example, in order to support the under-screen fingerprint detection of the liquid crystal display, the optical fingerprint system of the terminal device 10 may also include an excitation light source for optical fingerprint detection. The excitation light source may specifically be an infrared light source or a light source of invisible light of a specific wavelength, which may be arranged under the backlight module of the liquid crystal display or arranged in the edge area under the protective cover of the terminal device 10, and the The optical fingerprint device 130 can be arranged under the edge area of the liquid crystal panel or the protective cover and guided by the light path so that the fingerprint detection light can reach the optical fingerprint device 130; or, the optical fingerprint device 130 can also be arranged in the backlight module. Under the group, and the backlight module is designed to allow the fingerprint detection light to pass through the liquid crystal panel and the backlight module and reach the optical fingerprint device 130 through openings or other optical designs on the film layers such as diffuser, brightness enhancement film, and reflective film. . When the optical fingerprint device 130 adopts a built-in light source or an external light source to provide an optical signal for fingerprint detection, the detection principle is the same as that described above.

It should be understood that, in specific implementation, the terminal device 10 further includes a transparent protective cover, and the cover may be a glass cover or a sapphire cover, which is located above the display screen 120 and covers the terminal. The front of the device 10. Because, in the embodiment of the present application, the so-called finger pressing on the display screen 120 actually refers to pressing on the cover plate above the display screen 120 or covering the surface of the protective layer of the cover plate.

On the other hand, in some embodiments, the optical fingerprint device 130 may specifically include a plurality of optical fingerprint sensors; the plurality of optical fingerprint sensors may be arranged side by side under the display screen 120 in a splicing manner, and The sensing areas of the multiple optical fingerprint sensors collectively constitute the fingerprint detection area 103 of the optical fingerprint device 130. In other words, the fingerprint detection area 103 of the optical fingerprint device 130 may include multiple sub-areas, and each sub-area corresponds to the sensing area of one of the optical fingerprint sensors, so that the fingerprint collection area of the optical fingerprint module 130 103 can be extended to the main area of the lower half of the display screen, that is, to the area where the finger is habitually pressed, so as to realize the blind fingerprint input operation. Alternatively, when the number of optical fingerprint sensors is sufficient, the fingerprint detection area 130 can also be extended to half of the display area or even the entire display area, thereby realizing half-screen or full-screen fingerprint detection.

Optionally, in some embodiments of the present application, the optical fingerprint device 130 may further include a circuit board for transmitting signals (such as the fingerprint detection signal). For example, the circuit board may be a flexible printed circuit board (Flexible Printed Circuit Board). Circuit, FPC). The optical fingerprint sensor can be connected to the FPC, and through the FPC, electrical interconnection and signal transmission with other peripheral circuits or other elements in the electronic device are realized. For example, the optical fingerprint sensor may receive the control signal of the processing unit of the electronic device through the FPC, and may also output a fingerprint detection signal (for example, a fingerprint image) to the processing unit of the electronic device through the FPC or Control unit, etc.

It should be noted that, for ease of understanding, in the embodiments shown below, for the structures shown in different embodiments, the same structures are given the same reference numerals, and for brevity, detailed descriptions of the same structures are omitted. .

It should be understood that the heights or thicknesses of various structural members in the embodiments of the present application shown below and the overall thickness of the optical fingerprint device are only exemplary descriptions, and should not constitute any limitation to the present application.

In some embodiments, as shown in FIG. 2, the optical fingerprint chip 207 interconnects the chip electrical connection pad 201 and the electrical connection pad 206 of the FPC 208 through a gold wire 205, and an optical structure is provided above the optical fingerprint chip 207 The upper surface of the optical structure layer 203 is provided with a microlens array 204. Among them, the microlens array 204 and the pixel unit 202 inside the optical fingerprint chip 207 have a one-to-one correspondence. After cutting the optical fingerprint chip, the filter 209 is placed above the microlens array in the form of external placement, with an air gap between it and the microlens array 204.

Since the filter 209 needs to be supported and placed, the area size of the filter 209 may be larger than the area size of the optical fingerprint chip 207, which will result in higher filter cost.

Based on the above problems, the embodiments of the present application propose a new optical fingerprint device, which can reduce the area of the filter, thereby effectively reducing the production cost of the optical fingerprint device.

Hereinafter, the aforementioned optical sensing unit 131 is also referred to as a pixel unit, and the sensing array 133 is also referred to as a pixel array.

The optical fingerprint device 300 according to an embodiment of the present application will be described in detail below with reference to FIG. 3. It should be understood that, in the embodiment of the present application, the optical fingerprint device 300 may correspond to the optical fingerprint identification device 130 in FIG. 1. It should be noted that the optical fingerprint device in the embodiments of the present application may also be referred to as an optical fingerprint recognition module, a fingerprint recognition device, a fingerprint recognition module, a fingerprint module, a fingerprint acquisition device, etc., and the above terms can be replaced with each other.

As shown in FIG. 3, the optical fingerprint device 300 may include an optical filter 309, an optical path guiding structure 303, a redistribution layer 311, and an optical fingerprint chip 307.

Specifically, the filter 309 is used to filter out the optical signal of the target wavelength band, and transmit the optical signal of the target wavelength band (that is, the optical signal of the wavelength band required for fingerprint identification). The optical path guiding structure 303 is disposed under the filter 309, and is used to guide the optical signal returned from the reflection or scattering of the finger to the optical fingerprint chip 307. The optical fingerprint chip 307 includes a first pad 313 and a conductive via structure located under the first pad 313. The redistribution layer 311 includes a second pad, which is disposed under the optical fingerprint chip 307.

Wherein, the filter 309 and the optical fingerprint chip 307 are flush in the vertical direction, the first pad 313 is arranged on the upper surface of the optical fingerprint chip 307, and the conductive via structure is arranged inside the optical fingerprint chip 307 and communicates with the first pad 313 and the second pad. It can be seen from FIG. 3 that the arrangement of the first pad 313 does not protrude from the upper surface of the optical fingerprint chip 307, that is, the arrangement of the first pad 313 does not increase the thickness of the optical fingerprint chip 307.

The optical signal mentioned in the above content can carry fingerprint information of the finger, and fingerprint identification can be performed based on the fingerprint information. The light source used to illuminate the finger may be, for example, a light-emitting unit in a self-luminous display such as an OLED display screen, or other external excitation light sources, which are not limited here.

The optical signal may be a vertical optical signal or an oblique optical signal reflected by the finger. Among them, since the light intensity of the light signal obliquely incident on the finger is significantly increased after being reflected by the finger, the contrast of the fingerprint valley and ridge can be improved, and it has better fingerprint recognition performance for special fingers such as dry fingers.

In the embodiments of the present application, the optical fingerprint chip may be packaged by using a through silicon via (TSV) process. Specifically, the embodiment of the present application adopts the TSV packaging process to bond the filter and the optical fingerprint chip wafer together, perform TSV processing, and then lead the metal pads from the front surface of the optical fingerprint chip wafer to the optical fingerprint chip wafer. The back of the circle. Among them, the detailed processing flow of the filter and the optical fingerprint chip can be shown in Figure 4.

In 410, the filter is coated.

Specifically, coating the filter may include: coating the upper surface and/or the lower surface of the filter. The coating layer on one side of the filter (such as the upper surface) can be used for the wavelength band whose cut-off wavelength is shorter than 400 nm, and/or the coating layer on one side of the filter (such as the lower surface) can be used for the wavelength whose cut-off wavelength is longer than 600 nm.

It should be understood that in the embodiments of the present application, the coating layer may also be referred to as another name, such as an optical cut-off coating layer.

It should also be understood that the term "and/or" in this text is only an association relationship describing associated objects, indicating that three relationships can exist. For example, A and/or B can mean that A alone exists, and both A and B, there are three cases of B alone.

In 420, the filter and the optical fingerprint chip wafer front side are bonded together.

Optionally, the lower surface of the filter and the front surface of the optical fingerprint chip wafer can be bonded together with an optical adhesive.

In 430, the optical fingerprint chip wafer is thinned to achieve the required thickness.

Optionally, the thinning process of the optical fingerprint chip wafer may be, for example, using mechanical polishing, chemical substrate etching, and chemical mechanical polishing (Chemical Mechanical Polishing, CMP) to remove the wafer from the back of the optical fingerprint chip wafer. Material to thin the wafer. The thickness of the optical fingerprint chip wafer after the thinning process can be, for example, 30 microns or less and less than 80 microns, or even thinner.

In 440, TSV processing is performed on the thinned optical fingerprint chip wafer to obtain multiple conductive via structures.

The TSV process may include, for example, the formation of through holes, the formation of insulating sidewalls, and the filling of through holes. For details, please refer to the TSV process in the related art, which will not be repeated here.

The through holes in the plurality of conductive through hole structures may be vertical through holes or inclined through holes (for example, as shown in FIG. 3). When the through hole in the conductive through hole structure is an inclined through hole, the present application does not limit the inclination angle of the through hole, for example, it may be a clip between 45° and 90° with the lower surface of the optical fingerprint chip 307 angle.

In addition, the present application does not limit the shape of the through hole. For example, the cross section of the through hole may be circular, rectangular, trapezoidal or other polygonal shapes.

In 450, the optical fingerprint chip wafer and filter are simultaneously diced.

By cutting the optical fingerprint chip wafer and the filter at the same time, multiple optical fingerprint chips can be obtained. For example, the optical fingerprint chip 307 shown in FIG. 3 is one of the obtained multiple optical fingerprint chips. Since the filter and the optical fingerprint chip wafer are bonded together and then cut into a single piece, the filter 309 in FIG. 3 has the same size and area as the optical fingerprint chip 307. For example, the optical filter 309 and the optical fingerprint chip 307 are both 8 inches.

In this way, the solution of the embodiment of the present application can reduce the area of the filter, thereby reducing the cost of the optical fingerprint device.

The optical fingerprint device 300 of the embodiment of the present application will be described in detail below in conjunction with a single packaged product (ie, the optical fingerprint chip 307) obtained after cutting.

For the optical fingerprint chip 307, under the first pad 313, the electrical connection of the first pad 313 can be connected to the back surface of the optical fingerprint chip 307 through the rewiring layer 311 through the TSV process.

Optionally, the rewiring layer 311 and the optical fingerprint chip 307 are electrically isolated by the first insulating layer 305. The arrangement of the first insulating layer 305 can prevent the rewiring layer 311 and the optical fingerprint chip 307 from being electrically connected, thereby causing leakage and short circuits.

Further, a second insulating layer 310 is provided between the lines of the redistribution layer 311, and the second insulating layer 311 can function as isolation protection.

In this case, the conductive via structure may include the second insulating layer 310, the redistribution layer 311, and the first insulating layer 305.

It should be noted that the embodiment of the present application does not limit the materials of the first insulating layer 305 and the second insulating layer 311. At the same time, the embodiment of the present application does not limit the thickness of the first insulating layer 305 and the second insulating layer 311.

Optionally, in the embodiment of the present application, the optical fingerprint device may further include:

Flexible circuit board 308. The optical filter 309 and the optical fingerprint chip 307 can be integrated on the flexible circuit board 308 after being cut. The flexible circuit board 308 may be electrically connected to modules or units other than the optical fingerprint device 300. For example, the flexible circuit board 308 may be electrically connected to the processor or memory of an electronic device (for example, a mobile phone), which is not limited in the embodiment of the present application. .

Optionally, in the embodiment of the present application, the optical fingerprint device 300 may further include:

The electrical connection layer 312 is disposed between the redistribution layer 311 and the flexible circuit board 308. The redistribution layer 311 is electrically connected to the flexible circuit board 308 through the electrical connection layer 312 to transmit the electrical signal converted by the optical fingerprint chip 307 to the flexible circuit board 308.

The electrical connection layer 312 may be surface mounting technology (SMT) solder, anisotropic conductive film (ACF) or other metal layers. When the electrical connection layer 312 is a metal layer, the metal layer may include at least one of the following: a copper layer, a gold layer, and an alloy layer. That is, the metal layer can be a layer of metal or a stack of multiple layers of metal.

The transparent optical adhesive layer 301 is disposed between the filter 309 and the light path guiding structure 303 for bonding the filter 309 and the light path guiding structure 303. It should be understood that the transparent optical adhesive layer 301 is also the optical adhesive mentioned in the foregoing.

Optionally, in the embodiment of the present application, as shown in FIG. 5, the light path guiding structure 303 may include a micro lens array 3031. The material of the microlens array 3031 is a transparent medium, and the light transmittance of the transparent medium is greater than 99%. For example, the material of the micro lens array 3031 may be resin or the like.

In this case, the transparent optical glue layer 301 can be disposed between the filter 309 and the microlens array 3031, and/or the transparent optical glue layer 301 can be disposed between the filter 309 and the non-microlens in the light path guiding structure Between arrays. Specifically, a transparent optical adhesive layer 301 may be provided at least partially above the microlens array 3031, and/or a transparent optical adhesive layer 301 may be provided at least partially above the non-microlens array.

It can be seen that when the transparent optical glue layer 301 is provided on all upper positions of the micro lens array 3031, there is no air layer between the filter 309 and the micro lens array 3031. In other cases, for example, when the filter 309 is glued to a local position of the microlens array 3031 through the transparent optical glue layer 301, there is an air layer between the filter 309 and the microlens array 3031.

Optionally, the refractive index of the transparent optical glue layer 301 may be lower than the refractive index of the microlens array 3031. For example, the refractive index of the transparent optical adhesive layer 301 may range from 1.3 to 1.7, and the light transmittance may be greater than or equal to 95%.

The microlens array 3031 may include a plurality of microlens units, and the curvatures of the plurality of microlens units are the same in different directions. The upper surface of each micro lens unit may be a spherical aspheric surface. Optionally, the shape and size of each microlens unit in the plurality of microlens units may be the same or different, which is not specifically limited in the embodiment of the present application. The micro lens unit in the micro lens array 3031 can increase the incident angle of the central field of view, increase the inflow of light, and thus can improve the imaging quality. At the same time, the microlens unit in the microlens array 3031 can minimize the interference of large-angle incident light in adjacent areas, thereby reducing the crosstalk problem between adjacent units, and thereby improving the imaging quality.

Optionally, the light path guiding structure 303 may further include an optical structure layer 3032. The optical structure layer 3032 may be, for example, at least one light blocking layer.

Optionally, the light blocking rate of the light blocking area of the light blocking layer is greater than or equal to 95%.

The light-blocking layer may include a plurality of light-passing holes, and the microlens array 3031 is used to converge light signals in a specific direction to the light-passing holes, and converge light signals in a non-specific direction to the light-blocking layer of the light-blocking layer. area. The upper surface of the optical fingerprint chip 307 is provided with a pixel array 302 having a plurality of pixel units, and the specific direction optical signal can be transmitted to the pixel units in the pixel array 302 in the optical fingerprint chip 307 through a plurality of light-passing holes.

Through the arrangement of the microlens array 3031, the light blocking layer 270, the light-passing hole and the pixel unit, the light signal from the upper side of the micro-lens unit is condensed to the light-passing hole, and is transmitted to the pixel unit through the light-passing hole. In this way, the pixel unit can detect the light signal from the corresponding area above the microlens unit, and then can obtain the pixel value according to the light intensity of the light signal.

Optionally, the light-passing hole may be cylindrical, that is, the light-passing hole may be a hole in the light blocking layer. The diameter of the light-passing hole can be greater than 100 nm, so as to transmit the required light for imaging. In addition, the diameter of the light-passing hole should also be smaller than a predetermined value to ensure that the light-blocking layer can block unwanted light. That is to say, the parameter setting of the light-passing hole is as far as possible to maximize the transmission of the optical signal required for imaging of the optical fingerprint device 300 to the pixel unit, and the unnecessary light is blocked to the maximum.

Optionally, the multiple microlens units correspond to multiple pixel units in the pixel array 302 in a one-to-one correspondence. That is, the micro lens array 3031 includes a first micro lens unit, and the pixel array 302 includes a first pixel unit. The first micro lens unit is used to converge the first optical signal from above the first micro lens unit to the first micro lens unit. The first pixel unit corresponding to the micro lens unit.

Further, the first pixel unit may also be used to process the first light signal to obtain the first fingerprint image electrical signal, and the first fingerprint image electrical signal is a unit pixel in the fingerprint image.

Each pixel unit in the pixel array 302 may adopt a photodiode (photodiode), a metal oxide semiconductor field effect transistor (metal oxide semiconductor field effect transistor, MOSFET) and other devices. The shape of each pixel unit may be a polygon, such as the matrix shown in FIG. 3.

The coating layer is used to absorb light in a specific wavelength band. Exemplarily, the specific wavelength band may be 570-700 nm, that is, the light of the specific wavelength band is red light. The coating layer has a wavelength absorption rate of 570-700 nm that is greater than 80%.

As an example, the coating layer can be provided between the filter 309 and the coating layer on the upper surface of the filter, and/or the coating layer can be provided between the filter 309 and the coating layer on the lower surface of the filter between.

As another example, the coating layer may be disposed under the micro lens array 3031.

In the embodiment of this application, the optical fingerprint chip is packaged by the TSV process, that is, the filter and the optical fingerprint chip are bonded together and then cut in one piece. Therefore, the filter has the same size and area as the optical fingerprint chip, which reduces The area of the filter can effectively reduce the production cost of the optical fingerprint device.

The device embodiment of the present application is described in detail above in conjunction with Figures 3 to 5, and the method embodiment of the present application is described in detail below in conjunction with Figure 5. It should be understood that the method embodiment and the device embodiment correspond to each other, and similar descriptions can be Refer to the device embodiment.

Fig. 6 shows a schematic flow chart of a manufacturing method of an optical fingerprint device according to an embodiment of the present application. It should be understood that the steps or operations in FIG. 6 are only examples, and the embodiment of the present application may also perform other operations or variations of various operations in FIG. 6. In addition, each step in FIG. 6 may be executed in a different order from that shown in FIG. 6, and it may not be necessary to perform all the operations in FIG. 6.

As shown in Figure 6, the manufacturing method of the optical fingerprint device may include the following steps:

In 610, the optical filter, the optical path guiding structure, the optical fingerprint chip wafer, and the redistribution layer are bonded together. Among them, the optical filter is used to filter out the optical signal of the non-target waveband and pass the optical signal of the target waveband , The optical path guiding structure is arranged under the filter, and is used to guide the optical signal reflected or scattered from the finger to the optical fingerprint chip wafer. The optical fingerprint chip wafer is arranged under the optical path guiding structure, and the redistribution layer is arranged on the optical Below the fingerprint chip.

In 620, the optical fingerprint chip wafer is thinned.

In 630, TSV processing is performed on the back of the optical fingerprint chip wafer to form a conductive via structure inside the optical fingerprint chip wafer. The conductive via structure connects the first pad of the optical fingerprint chip wafer to the heavy The second pad of the wiring layer.

In 640, the optical filter, optical path guiding structure, optical fingerprint chip wafer, and redistribution layer are integratedly cut.

Optionally, in some embodiments, the method 600 further includes: integrally cutting the filter, the optical path guiding structure, the optical fingerprint chip wafer, and the redistribution layer and then connecting them to the top of the flexible circuit board.

Optionally, in some embodiments, the optical filter, the optical path guiding structure, the optical fingerprint chip wafer, and the redistribution layer are integrally cut and connected to the top of the flexible circuit board, which may specifically include: guiding the optical filter and optical path After the structure, the optical fingerprint chip wafer, and the redistribution layer are integratedly cut, they are connected to the upper side of the flexible circuit board through the electrical connection layer to transmit the electrical signals obtained by the optical fingerprint chip wafer conversion to the flexible circuit board.

Optionally, in some embodiments, the electrical connection layer is an anisotropic conductive adhesive ACF layer or surface mount process SMT solder.

Optionally, in some embodiments, the area of the filter is the same as the area of the optical fingerprint chip.

Optionally, in some embodiments, the method 600 further includes: adhering the filter and the light path guiding structure through a transparent optical adhesive layer.

Optionally, in some embodiments, the optical path guiding structure includes a microlens array, and the optical filter and the optical path guiding structure are bonded through a transparent optical adhesive layer, which may specifically include: passing between the optical filter and the microlens array The transparent optical glue layer is bonded, and/or the transparent optical glue layer is bonded between the filter and the non-microlens array in the light path guiding structure.

Optionally, in some embodiments, the transparent optical glue layer is disposed at least partly above the microlens array, and/or the transparent optical glue layer is disposed at least partly above the non-microlens array.

Optionally, in some embodiments, the refractive index of the transparent optical glue layer is lower than the refractive index of the microlens array.

Optionally, in some embodiments, the microlens array includes a plurality of microlens units, and the optical fingerprint chip wafer includes a plurality of pixel units; wherein, the first microlens unit of the plurality of microlens units is used to transfer the The first optical signal above a micro lens unit is converged to a first pixel unit corresponding to the first micro lens unit among the plurality of pixel units.

Optionally, in some embodiments, the method 600 further includes: forming a first insulating layer between the redistribution layer and the optical fingerprint chip wafer to electrically isolate the redistribution layer and the optical fingerprint chip wafer.

Optionally, in some embodiments, the method 600 further includes: forming a second insulating layer between the lines of the redistribution layer.

Optionally, in some embodiments, the method 600 further includes: filling the second insulating layer, the rewiring layer, and the first insulating layer in the conductive via structure.

Optionally, in some embodiments, before bonding the filter, the optical path guiding structure, the optical fingerprint chip wafer, and the redistribution layer into one body, the method 600 further includes: on the upper surface of the filter and/or Make a coating layer on the bottom surface.

Optionally, in some embodiments, the coating layer on the upper surface of the filter is used to cut off wavelengths shorter than 400 nm, and/or the coating on the lower surface of the filter is used to cut off wavelengths longer than 600 nm.

Optionally, in some embodiments, the method 600 further includes: making a coating layer for absorbing light of a specific wavelength band.

Optionally, in some embodiments, the specific wavelength band is 570nm-700nm.

Optionally, in some embodiments, the absorption rate of the coating layer to absorb light in a specific wavelength band is greater than or equal to 80%.

Optionally, in some embodiments, the preparation of the coating layer may specifically include: preparing a coating layer between the filter and the coating layer on the upper surface of the filter, and/or, in the filter and A coating layer is made between the coating layers on the lower surface of the filter.

Optionally, in some embodiments, the manufacturing of the coating layer may specifically include: manufacturing the coating layer under the light path guiding structure.

An embodiment of the present application also provides an electronic device 700. As shown in FIG. 7, the electronic device 700 may include a display screen 720 and an optical fingerprint device 710. The optical fingerprint device 710 may be the optical fingerprint device in the foregoing embodiment. 300 and arranged below the display screen 720. Wherein, as an optional embodiment, the display screen 520 has a self-luminous display unit, and the self-luminous display unit can be used as an excitation light source for the optical fingerprint device 710 for fingerprint detection.

It should be understood that the specific examples in the embodiments of the present application are only intended to help those skilled in the art to better understand the embodiments of the present application, rather than limiting the scope of the embodiments of the present application.

It should be understood that the terms used in the embodiments of the present application and the appended claims are only for the purpose of describing specific embodiments, and are not intended to limit the embodiments of the present application. For example, the singular forms of "a", "above" and "the" used in the embodiments of this application and the appended claims are also intended to include plural forms, unless the context clearly indicates other meanings.

A person of ordinary skill in the art may be aware that, in combination with the examples described in the embodiments disclosed herein, the units can be implemented by electronic hardware, computer software, or a combination of both, in order to clearly illustrate the interchangeability of hardware and software. In the above description, the composition and steps of each example have been described generally in terms of function. Whether these functions are executed by hardware or software depends on the specific application and design constraint conditions of the technical solution. Professionals and technicians can use different methods for each specific application to implement the described functions, but such implementation should not be considered beyond the scope of this application.

In the several embodiments provided in this application, it should be understood that the disclosed system and device may be implemented in other ways. For example, the device embodiments described above are only illustrative. For example, the division of the units is only a logical function division, and there may be other divisions in actual implementation, for example, multiple units or components can be combined or It can be integrated into another system, or some features can be ignored or not implemented. In addition, the displayed or discussed mutual coupling or direct coupling or communication connection may be indirect coupling or communication connection through some interfaces, devices or units, and may also be electrical, mechanical or other forms of connection.

The units described as separate components may or may not be physically separated, and the components displayed as units may or may not be physical units, that is, they may be located in one place, or they may be distributed on multiple network units. Some or all of the units may be selected according to actual needs to achieve the objectives of the solutions of the embodiments of the present application.

In addition, the functional units in the various embodiments of the present application may be integrated into one processing unit, or each unit may exist alone physically, or two or more units may be integrated into one unit. The above-mentioned integrated unit can be implemented in the form of hardware or software functional unit.

If the integrated unit is implemented in the form of a software functional unit and sold or used as an independent product, it can be stored in a computer readable storage medium. Based on this understanding, the technical solution of this application is essentially or the part that contributes to the existing technology, or all or part of the technical solution can be embodied in the form of a software product, and the computer software product is stored in a storage medium It includes several instructions to make a computer device (which may be a personal computer, a server, or a network device, etc.) execute all or part of the steps of the methods described in the various embodiments of the present application. The aforementioned storage media include: U disk, mobile hard disk, read-only memory (ROM, Read-Only Memory), random access memory (RAM, Random Access Memory), magnetic disk or optical disk and other media that can store program code .

The above are only specific implementations of this application, but the protection scope of this application is not limited to this. Anyone familiar with the technical field can easily think of various equivalents within the technical scope disclosed in this application. Modifications or replacements, these modifications or replacements shall be covered within the protection scope of this application. Therefore, the protection scope of this application shall be subject to the protection scope of the claims.

Claims

An optical fingerprint device, characterized by comprising:

The filter is used to filter out the optical signal of the non-target waveband and pass the optical signal of the target waveband;

The optical path guiding structure is arranged under the optical filter, and is used to guide the optical signal returned from the reflection or scattering of the finger to the optical fingerprint chip;

The optical fingerprint chip is disposed under the optical path guiding structure, and the optical fingerprint chip includes a first pad and a conductive via structure located under the first pad;

The redistribution layer is arranged under the optical fingerprint chip, and the redistribution layer includes a second pad;

Wherein, the filter and the optical fingerprint chip are flush in the vertical direction, the first pad is arranged on the upper surface of the optical fingerprint chip, and the conductive via structure is arranged on the optical fingerprint chip It is internally connected with the first pad and the second pad.
The optical fingerprint device according to claim 1, wherein the optical fingerprint device further comprises:

The flexible circuit board is arranged under the redistribution layer;

Wherein, the filter and the optical fingerprint chip are integrally cut and arranged above the flexible circuit board.
The optical fingerprint device according to claim 2, wherein the optical fingerprint device further comprises:

The electrical connection layer is arranged between the rewiring layer and the flexible circuit board, and the rewiring layer is electrically connected to the flexible circuit board through the electrical connection layer to convert the optical fingerprint chip into The electrical signal is transmitted to the flexible circuit board.
4. The optical fingerprint device of claim 3, wherein the electrical connection layer is an anisotropic conductive adhesive ACF layer or a surface mount process SMT solder.
The optical fingerprint device according to any one of claims 1 to 4, wherein the area of the filter is the same as the area of the optical fingerprint chip.
The optical fingerprint device according to any one of claims 1 to 5, wherein the optical fingerprint device further comprises:

The transparent optical adhesive layer is arranged between the filter and the light path guiding structure, and is used for bonding the filter and the light path guiding structure.
The optical fingerprint device according to claim 6, wherein the optical path guiding structure comprises a micro lens array, and the transparent optical glue layer is disposed between the filter and the micro lens array, and/or , Arranged between the filter and the non-microlens array in the optical path guiding structure.
The optical fingerprint device according to claim 7, wherein the transparent optical glue layer is provided at least partly above the microlens array, and/or, at least partly above the non-microlens array is provided There is the transparent optical adhesive layer.
The optical fingerprint device according to claim 7 or 8, wherein the refractive index of the transparent optical glue layer is lower than the refractive index of the microlens array.
The optical fingerprint device according to any one of claims 7 to 9, wherein the micro lens array includes a plurality of micro lens units, and the optical fingerprint chip includes a plurality of pixel units;

Wherein, the first microlens unit of the plurality of microlens units is used to converge the first optical signal from above the first microlens unit into the plurality of pixel units and the first microlens unit The corresponding first pixel unit.
The optical fingerprint device according to any one of claims 1 to 10, wherein the rewiring layer and the optical fingerprint chip are electrically isolated by a first insulating layer.
The optical fingerprint device according to any one of claims 1 to 11, wherein a second insulating layer is provided between the lines of the redistribution layer.
The optical fingerprint device according to claim 12, wherein the conductive via structure comprises the second insulating layer, the redistribution layer and the first insulating layer.
The optical fingerprint device according to any one of claims 1 to 13, wherein a coating layer is provided on the upper surface and/or the lower surface of the filter.
The optical fingerprint device according to claim 14, wherein the coating layer on the upper surface of the filter is used to cut off wavelengths shorter than 400nm, and/or the coating layer on the lower surface of the filter is used to cut off Wavelengths longer than 600nm.
The optical fingerprint device according to any one of claims 1 to 15, wherein the optical fingerprint device further comprises:

The coating layer is used to absorb light in a specific wavelength band.
The optical fingerprint device according to claim 16, wherein the specific wavelength band is 570nm-700nm.
The optical fingerprint device according to claim 16 or 17, wherein the absorption rate of the coating layer to absorb the light of the specific wavelength band is greater than or equal to 80%.
The optical fingerprint device according to any one of claims 16 to 18, wherein the coating layer is disposed between the filter and the coating layer on the upper surface of the filter, and/or , The coating layer is arranged between the filter and the coating layer on the lower surface of the filter.
The optical fingerprint device according to any one of claims 16 to 18, wherein the coating layer is disposed under the light path guiding structure.
A manufacturing method of an optical fingerprint device, characterized in that the method includes:

The optical filter, the optical path guiding structure, the optical fingerprint chip wafer, and the redistribution layer are bonded into one body. The optical filter is used to filter out the optical signal of the non-target wavelength band and transmit the optical signal of the target wavelength band. The optical path guiding structure is disposed under the optical filter, and is used to guide the optical signal reflected or scattered from the finger to the optical fingerprint chip wafer, and the optical fingerprint chip wafer is disposed on the optical path guiding structure Below, the redistribution layer is arranged under the optical fingerprint chip;

Thinning the optical fingerprint chip wafer;

Perform TSV processing on the back of the optical fingerprint chip wafer to form a conductive via structure inside the optical fingerprint chip wafer, and the conductive via structure communicates with the first optical fingerprint chip wafer A bonding pad and a second bonding pad of the rewiring layer;

The optical filter, the optical path guiding structure, the optical fingerprint chip wafer, and the redistribution layer are integrally cut.
22. The manufacturing method according to claim 21, wherein the manufacturing method further comprises:

The optical filter, the optical path guiding structure, the optical fingerprint chip wafer, and the redistribution layer are integrally cut and connected to the top of the flexible circuit board.
The manufacturing method according to claim 21 or 22, characterized in that the said filter, optical path guiding structure, optical fingerprint chip wafer, and redistribution layer are integratedly cut and then connected to the top of the flexible circuit board, comprising :

After the filter, the optical path guiding structure, the optical fingerprint chip wafer, and the redistribution layer are integrally cut, they are connected to the top of the flexible circuit board through an electrical connection layer to convert the electrical signals obtained by the optical fingerprint chip wafer To the flexible circuit board.
The manufacturing method according to claim 24, wherein the electrical connection layer is an anisotropic conductive adhesive ACF layer or a surface mount process SMT solder.
The manufacturing method according to any one of claims 21 to 24, wherein the area of the filter is the same as the area of the optical fingerprint chip.
The manufacturing method according to any one of claims 21 to 25, wherein the manufacturing method further comprises:

The optical filter and the optical path guiding structure are bonded through a transparent optical adhesive layer.
The manufacturing method according to claim 26, wherein the light path guiding structure comprises a microlens array, and bonding the filter and the light path guiding structure through a transparent optical glue layer, comprising:

Bonding between the filter and the microlens array through the transparent optical adhesive layer, and/or between the filter and the non-microlens array in the optical path guiding structure The transparent optical adhesive layer is bonded.
The manufacturing method according to claim 27, wherein the transparent optical glue layer is disposed at least partially above the microlens array, and/or the transparent optical glue layer is disposed on the non-microlens At least part of the upper position of the array.
The manufacturing method according to claim 27 or 28, wherein the refractive index of the transparent optical glue layer is lower than the refractive index of the micro lens array.
The manufacturing method according to any one of claims 27 to 29, wherein the microlens array includes a plurality of microlens units, and the optical fingerprint chip wafer includes a plurality of pixel units;

Wherein, the first microlens unit of the plurality of microlens units is used to converge the first optical signal from above the first microlens unit into the plurality of pixel units and the first microlens unit The corresponding first pixel unit.
The manufacturing method according to any one of claims 21 to 30, wherein the manufacturing method further comprises:

A first insulating layer is formed between the redistribution layer and the optical fingerprint chip wafer to electrically isolate the redistribution layer and the optical fingerprint chip wafer.
The manufacturing method according to claim 21 or 31, wherein the manufacturing method further comprises:

A second insulating layer is formed between the lines of the redistribution layer.
The manufacturing method according to claim 32, wherein the manufacturing method further comprises:

The second insulating layer, the redistribution layer, and the first insulating layer are filled in the conductive via structure.
The manufacturing method according to any one of claims 21 to 33, characterized in that, before bonding the filter, the optical path guiding structure, the optical fingerprint chip wafer, and the redistribution layer into one body, the manufacturing method also include:

A coating layer is made on the upper surface and/or the lower surface of the filter.
The manufacturing method according to claim 34, wherein the coating layer on the upper surface of the filter is used for cut-off wavelengths shorter than 400nm, and/or the coating layer on the lower surface of the filter is used for the cut-off wavelength Wave band longer than 600nm.
The manufacturing method according to any one of claims 21 to 35, wherein the manufacturing method further comprises:

A coating layer is made, and the coating layer is used to absorb light of a specific wavelength band.
The manufacturing method according to claim 36, wherein the specific wavelength band is 570nm-700nm.
The manufacturing method according to claim 36 or 37, wherein the absorption rate of the coating layer to absorb light in the specific wavelength band is greater than or equal to 80%.
The manufacturing method according to any one of claims 36 to 38, wherein the manufacturing the coating layer comprises:

The coating layer is made between the filter and the coating layer on the upper surface of the filter, and/or, between the filter and the coating layer on the lower surface of the filter The coating layer.
The manufacturing method according to any one of claims 36 to 38, wherein the manufacturing the coating layer comprises:

The coating layer is made under the light path guiding structure.
An electronic device, characterized in that, the electronic device includes:

Display screen

The optical fingerprint device according to any one of claims 1 to 20.