CN216528902U - Optical chip packaging structure and electronic equipment - Google Patents

Abstract

The application provides an optical chip's packaging structure and electronic equipment, can promote optical chip's detection performance. The packaging structure of the optical chip comprises: the optical chip comprises a substrate, a chip bonding adhesive film and an optical chip; the chip bonding adhesive film is arranged between the substrate and the optical chip and used for bonding the substrate and the optical chip, the chip bonding adhesive film is a dark chip bonding adhesive film, and the chip bonding adhesive film is also used for absorbing an optical signal passing through the optical chip so as to prevent the optical signal from interfering with optical detection of the optical chip after being reflected by the substrate. Through the technical scheme of this application embodiment, except utilizing chip laminating glued membrane to bond optical chip and base plate, can also design it into dark, directly utilize dark chip laminating glued membrane to absorb the light signal that passes through optical chip, prevent this light signal that passes through optical chip from reaching the surface of base plate, again by the optical detection performance of base plate reflection influence optical chip.

Description

Optical chip packaging structure and electronic equipment

Technical Field

The present application relates to the field of optical chip technology, and more particularly, to a package structure of an optical chip and an electronic device.

Background

With the rapid development of chip technology, optical chips have played an important role in various fields as a branch which is not negligible.

As an example, the optical chip may be used as a biometric detection chip, and is disposed in a consumer electronic product such as a mobile phone, a computer, a wearable device, etc., and by detecting a biometric optical signal passing through a user to detect biometric information such as a fingerprint, a human face, blood pressure, blood oxygen, etc. of the user, the electronic device may perform various related functions based on the biometric information, thereby greatly improving the user experience of the user on the electronic device.

Therefore, it is an object of the present invention to provide an optical chip for performing related functions by detecting optical signals, which can improve the quality of the detected optical signals and further improve the detection performance of the optical chip.

SUMMERY OF THE UTILITY MODEL

The application provides an optical chip's packaging structure and electronic equipment, can promote optical chip's detection performance.

In a first aspect, a package structure of an optical chip is provided, which includes: the optical chip comprises a substrate, a chip bonding adhesive film and an optical chip; the chip bonding adhesive film is arranged between the substrate and the optical chip and used for bonding the substrate and the optical chip, the chip bonding adhesive film is a dark chip bonding adhesive film, and the chip bonding adhesive film is also used for absorbing an optical signal passing through the optical chip so as to prevent the optical signal from interfering with optical detection of the optical chip after being reflected by the substrate.

Through the technical scheme of this application embodiment, except utilizing chip laminating glued membrane to bond optical chip and base plate, can also design it into dark, directly utilize dark chip laminating glued membrane to absorb the light signal that passes through optical chip, prevent this light signal that passes through optical chip from reaching the surface of base plate, again by the optical detection performance of base plate reflection influence optical chip. In addition, on the basis of ensuring the optical detection performance of the optical chip, the technical scheme can not introduce additional manufacturing processes and materials, such as black solder resist ink, vapor deposition black nickel and the like, to cover the surface of the substrate, so that the overall manufacturing cost of the packaging structure is reduced, and the problems of environmental protection, reliability and the like can not be introduced.

In some possible embodiments, the die-bonding adhesive film is a black die-bonding adhesive film.

In some possible embodiments, the light transmittance of the die attach adhesive film is 50% or less.

In some possible embodiments, the gloss of the die attach adhesive film is 200GU or less at a measurement angle of 60 °.

In some possible embodiments, the thickness of the die attach adhesive film is greater than or equal to 10 μm and less than or equal to 30 μm.

In some possible embodiments, the thickness of the optical chip is less than or equal to 300 μm.

In some possible embodiments, the optical chip is an optical fingerprint sensor chip.

In some possible embodiments, the package structure further includes: a microlens layer and at least one diaphragm layer; the microlens layer includes a microlens array formed of a plurality of microlenses; the optical fingerprint sensor chip comprises a photosensitive array formed by a plurality of photosensitive units; this at least one diaphragm layer sets up between this microlens layer and this optics fingerprint sensor chip, and every diaphragm layer includes in this at least one diaphragm layer: the light guide device comprises a light blocking layer and a plurality of diaphragm holes, wherein the diaphragm holes in the at least one diaphragm layer are used for forming a plurality of light guide channels, each light guide channel in the plurality of light guide channels corresponds to one photosensitive unit in the photosensitive array, and each light guide channel is used for transmitting a fingerprint light signal which passes through a finger of a user and is converged by the micro lens to the corresponding photosensitive unit so as to perform fingerprint detection.

In some possible embodiments, the substrate includes a printed circuit board, and the optical chip is adhered to a surface of the printed circuit board by the die attach adhesive film.

In some possible embodiments, the substrate includes a flexible circuit board and a stiffener, the optical chip is adhered to a surface of the flexible circuit board through the die attach adhesive film, and the stiffener is used for supporting and stiffening the flexible circuit board and the optical chip.

In some possible embodiments, the substrate includes a flexible circuit board and a stiffener, the flexible circuit board has an opening therein, the optical chip is located in the opening and is bonded to the stiffener through the die attach adhesive film, and the stiffener is used for supporting and stiffening the flexible circuit board and the optical chip.

In some possible embodiments, the package structure further includes: the optical chip comprises a metal lead and lead protection glue, wherein the metal lead is used for electrically connecting the optical chip and the substrate, and the lead protection glue coats the metal lead and is used for supporting and protecting the metal lead.

In a second aspect, an electronic device is provided, comprising: a processing unit and an optical chip package structure as in the first aspect or any one of the possible embodiments of the first aspect, wherein the processing unit is configured to receive a detection signal of the optical chip through the substrate and process the detection signal.

In some possible embodiments, the electronic device further comprises: the display screen, this optical chip is optics fingerprint sensor chip, and this optics fingerprint sensor chip sets up in this display screen below.

Drawings

Fig. 1 is a schematic structural diagram of a package structure of an optical chip according to an embodiment of the present application.

Fig. 2 is a schematic structural diagram of a package structure of another optical chip provided in an embodiment of the present application.

Fig. 3 is a schematic structural diagram of a package structure of another optical chip provided in an embodiment of the present application.

Fig. 4 is a schematic structural diagram of a package structure of another optical chip provided in an embodiment of the present application.

Fig. 5 is a schematic structural diagram of a package structure of another optical chip provided in an embodiment of the present application.

Fig. 6 is a schematic top view of an electronic device according to an embodiment of the present disclosure.

Fig. 7 is a schematic cross-sectional structure diagram of an electronic device according to an embodiment of the present application.

Detailed Description

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

The technical scheme of the embodiment of the application can be applied to various electronic devices, and is particularly suitable for computers (computers) and peripheral 3C electronic products related to the computers, communication (Communications) and Consumer Electronics (Consumer Electronics), such as smart phones, notebook computers, tablet computers, intelligent wearable devices, household appliances, game devices and the like. In addition, the technical solutions related to the embodiments of the present application also relate to other types of electronic devices such as automotive electronics, and the embodiments of the present application are not particularly limited to this.

Specifically, the optical chip, as one of the chip types, needs to be electrically connected to an external electrical component through a packaging process in an actual application process, so as to provide a stable and reliable working environment for the optical chip, and perform a mechanical or environmental protection function on the optical chip, so that the optical chip can perform normal functions, and high stability and reliability are ensured.

As an example, fig. 1 shows a schematic structural diagram of a package structure 100 of an optical chip provided in an embodiment of the present application.

As shown in fig. 1, the package structure 100 of the optical chip may include: a substrate 110, a Die Attach Film (DAF) 120, and an optical chip 130.

Specifically, the optical chip 130 may include a light detection region 131 that may be used to detect and convert optical signals into electrical signals.

The substrate 110 is disposed below the optical chip 130, and is used for carrying the optical chip 130 and providing a package for the optical chip 130. Alternatively, the substrate 110 may be electrically connected to the optical chip 130 and used to transmit the electrical signal generated by the optical chip 130. As an example, the substrate 100 may be a Printed Circuit Board (PCB) having a certain strength and supporting the optical chip 130, and a metal wiring layer may be included in the PCB for transmitting an electrical signal of the optical chip 130. As another example, the substrate 100 may also include a Flexible Printed Circuit (FPC) and a stiffener for supporting the FPC and the optical chip 130.

The DAF 120 is disposed between the substrate 110 and the optical chip 120, and is used to bond and fix the optical chip 120 to the substrate 110. It will be appreciated that the DAF 120 is in a packaged configuration, which is embodied as a glue layer after peeling off the thin film substrate layer, which is used to double-side bond the optical chip 120 and the substrate 110, which is typically a transparent or white translucent color. For convenience of description, in the following description, DAF refers to a glue layer for double-sided adhesion in a package structure, and does not include other film substrate layers having an auxiliary function before packaging.

In this embodiment, the DAF 120 is transparent or white and translucent, when the optical chip 130 is used for detecting an optical signal, the strong optical signal 11 can penetrate through the optical chip 130 and the DAF 120 to reach the substrate 110, and after being reflected by the substrate 110, the strong optical signal is received by the light detection area 131 in the optical chip 130, and finally, the normal detection of the effective optical signal by the optical chip 130 is disturbed in the form of a noise signal, so that the optical detection performance of the optical chip is affected.

With the rapid development of chip technology, chips are becoming thinner and lighter, so as to reduce the space occupied by the chips in electronic equipment and facilitate the installation of the chips in the electronic equipment. In this case, when the thickness of the optical chip 130 is smaller, the noise interference of the optical chip 130 penetrating through the optical chip 130 and the DAF 120 and reflected back through the substrate 110 is more serious, and the optical detection performance of the optical chip is further affected.

In view of this, in some related arts, the whole surface of the substrate 110 is blackened, and the blackened substrate 110 has a strong light absorption function, so that the optical signal can be prevented from being reflected by the substrate 110 after reaching the substrate 110, and the reflected optical signal can be prevented from causing noise interference on the optical chip 130. However, in this solution, a special black coating and/or a special process is required for additional blackening treatment, which causes certain cost problems and other related problems. Specifically, if the substrate 110 is a printed circuit board, a special black solder resist ink is required to be used on the printed circuit board, and the black solder resist ink not only causes extra cost, but also may cause environmental problems, which is not favorable for popularization and use of the package structure 100. If the substrate 110 includes a flexible circuit board and a stiffener, the black solder resist ink is also used on the flexible circuit board, and a black film is prepared on the stiffener through a plating process, for example, black nickel is plated on the stiffener. The coating process is costly and the black nickel has poor adhesion, which may affect the overall reliability of the chip package structure 100.

In order to solve the above problem, the present application provides a schematic structure of another optical chip package structure 200.

As shown in fig. 2, in the embodiment of the present application, a package structure 200 of an optical chip includes: a substrate 210, a Die Attach Film (DAF)220, and an optical chip 230;

the DAF 220 is disposed between the substrate 210 and the optical chip 230 and used for adhering the optical chip 230 and the substrate 210, the DAF 200 is a dark DAF 220, and the dark DAF 200 is used for absorbing an optical signal passing through the optical chip 230 to prevent the optical signal from interfering with optical detection of the optical chip 230 after being reflected by the substrate 210.

Specifically, in the present embodiment, the substrate 210 is used for carrying and supporting the optical chip 230, providing a package of the optical chip 230. Optionally, in some embodiments, the substrate 210 may also be electrically connected to the optical chip 230 for transmitting the related electrical signal of the optical chip 230. As an example, the substrate 210 may receive the electrical signal generated by the optical chip 230 and transmit the electrical signal, for example, to a processing unit, which may process the electrical signal to perform a corresponding function. In addition, the substrate 210 may also be used to transmit control signals in a control unit or a processing unit to the optical chip 230 to control the operation of the optical chip 230.

Alternatively, the substrate 210 may include any type of circuit board, for example, the circuit board may be a printed circuit board, a flexible circuit board, a rigid-flex circuit board, or the like, and the specific type of the circuit board is not limited in this application. It should be noted that, when the substrate 210 includes a flexible circuit board, a reinforcing plate of the flexible circuit board is also needed to be included to reinforce and support the flexible circuit board and the optical chip 230, wherein the optical chip 230 may be disposed on the reinforcing plate, or may also be disposed in a region of the flexible circuit board having a reinforcing plate for reinforcement.

Alternatively, the optical chip 230 in the embodiment of the present application may be an optical sensor chip, also called a photo sensor chip, for performing optical signal detection. The optical signal detected by the optical chip 230 may be a visible light signal, an ultraviolet light signal, an infrared light signal, or the like. Specifically, the optical chip 230 is an unpackaged bare chip (die), or may also be referred to as a bare wafer.

In some embodiments, the optical chip 230 may include a plurality of photosensitive cells for detecting optical signals, and the plurality of photosensitive cells may form a photosensitive array for performing optical imaging, wherein each photosensitive cell in the photosensitive array may correspond to one pixel in an optical image. Alternatively, in other embodiments, the optical chip 230 may include only one photosensitive unit for detecting optical signals, and the photosensitive unit may detect the light intensity received by the photosensitive unit, and analyze the light intensity to perform various functions such as distance detection and biometric information detection. The light sensing unit includes, but is not limited to, a photodiode (Photo Diode) or a Photo transistor (Photo transistor), etc.

Based on the functions of the optical chip 230, as an example, the optical chip 230 may be applied to an optical biometric detection system, such as an optical fingerprint detection system, an optical face recognition system, an optical blood oxygen/blood pressure/heart rate detection system, and so on. As another example, the optical chip 230 may also be applied to an ambient light detection system, a distance detection system, and the like. The embodiment of the present application does not limit the specific application of the optical chip 230.

For the DAF 220, the main component may be epoxy resin, and in addition, other auxiliary substances may be included to adjust the color, optical properties, electrical properties, and the like of the DAF 220. By way of example, the dark colored DAF 220 in the embodiments of the present application may be formed by adding pigments to a currently transparent or white translucent DAF. Alternatively, in other examples, the dark-colored DAF 220 in the embodiment of the present application may be prepared by other related technologies, and the embodiment of the present application is not limited to a specific preparation method thereof.

The DAF 220 has viscosity at normal or high temperature, and can be fixed by a chemical reaction generated by baking, so as to achieve stable adhesion between the optical chip 230 and the substrate 210.

Through the technical scheme of the embodiment of the application, the optical chip 230 and the substrate 210 can be bonded by using the DAF 220, and the DAF 220 with the dark color can be designed into the dark color, so that the optical signal passing through the optical chip 230 is directly absorbed by using the DAF 220 with the dark color, and the optical signal passing through the optical chip 230 is prevented from reaching the surface of the substrate 210 and then reflected by the substrate 210 to influence the optical detection performance of the optical chip 230. According to the technical scheme, on the basis of ensuring the optical detection performance of the optical chip 230, additional manufacturing processes and materials, such as the black solder resist ink and the vapor deposition black nickel, are not introduced, so that the overall manufacturing cost of the packaging structure 200 is reduced, and the problems of environmental protection, reliability and the like are not introduced.

Alternatively, as shown in fig. 2, the DAF 220 may be a black DAF 220, which has a good light absorption property and can absorb a large amount of light signals transmitted through the optical chip 230.

By way of example, a black DAF 220 in the present example may be formed by adding carbon black pigment to a presently transparent or white translucent DAF. Alternatively, in other examples, the black DAF 220 in the embodiment of the present application may also be prepared by other related technologies, and the embodiment of the present application is not limited to a specific preparation method thereof.

Of course, the DAF 220 may be other darker colors besides black, such as: black brown, black red, dark green, etc., and also has superior light absorption properties.

Alternatively, the thickness of the DAF 220 is greater than a certain threshold to ensure high absorbance. As an example, the thickness of the DAF 220 may be above 10 μm. On the basis, the thickness of the DAF 220 may be further controlled within a certain threshold, so as to prevent the excessively thick DAF 220 glue layer from affecting the overall thickness of the package structure 200. By way of example, the thickness of the DAF 220 may be within 30 μm. That is, in the embodiment of the present application, the thickness of the DAF 220 is 10 μm or more and 30 μm or less.

Alternatively, since the DAF 220 has a superior light absorption property, the DAF 220 also has a lower light transmittance. As an example, the DAF 220 has a light transmittance of 50% or less.

Further, on the basis of ensuring that the DAF 220 has better light absorption performance and lower light transmittance, the DAF 220 may also have lower reflectivity, so as to prevent the light signal passing through the optical chip 230 from being reflected back to the optical chip 230 by the DAF 220 and affecting the light detection performance of the optical chip 230.

Generally, the lower the gloss of the surface of the object, the less specular the surface of the object is able to reflect light signals. As an example, for the DAF 220 in the embodiments of the present application, its glossiness may be 200GU or less at a measurement angle of 60 °.

In the above-mentioned embodiments, the DAF 220 has a better light absorption function, a lower light transmittance and a lower reflectivity, and can block the optical signal passing through the optical chip 230, so as to prevent the optical signal from interfering with the optical detection of the optical chip 230 after being reflected by the substrate 210 and/or the adhesive layer 220. Therefore, the thickness of the optical chip 230 can be thinner, even if a large amount of optical signals pass through the thinner optical chip 230, the optical chip 230 can be blocked by the DAF 220, and at the same time, the thinner optical chip 230 only needs to occupy a smaller space, which is beneficial to the development of the light and thin package structure 200.

As an example, the thickness of the optical chip 230 may be 300 μm or less.

Alternatively, as described in the above embodiments, the substrate 210 may include any type of circuit board and is electrically connected to the optical chip 230 to form the package structure 200 in the embodiment of the present application.

By way of example, in the following application embodiments, the DAF 200 is a black DAF 220, and in other examples, the black DAF 220 may be replaced by a dark DAF to absorb the optical signal passing through the optical chip 230.

Fig. 3 is a schematic structural diagram of a package structure 200 of another optical chip according to an embodiment of the present application.

As shown in fig. 3, in the package structure 200, the substrate 210 includes a printed circuit board 211. The optical chip 230 is attached to the surface of the printed circuit board 211 by the black DAF 220.

In addition to the printed circuit board 211, the black DAF 220, and the optical chip 230, the package structure 200 in the embodiment of the present application may further include an electrical connector 240 to electrically connect the printed circuit board 211 and the optical chip 230.

As an example, as shown in fig. 3, the electrical connector 240 may be a metal lead, the surfaces of the printed circuit board 211 and the optical chip 230 may be provided with metal pads, and the metal lead is used for connecting the printed circuit board 211 and the metal pads of the optical chip 230 to realize the electrical connection of the printed circuit board 211 and the optical chip 230.

Optionally, in cooperation with the fine metal leads, the package structure 200 further includes: and the lead protection glue 250 is used for coating the metal lead by the lead protection glue 250.

In the embodiment of the present application, since the package structure 200 is provided with the black DAF 220 to absorb and block the optical signal passing through the optical chip 230, the solder mask layer on the surface of the printed circuit board 211 may not need to use black solder mask ink, i.e., the solder mask layer on the surface of the printed circuit board 211 is a non-black solder mask layer, which may be green, white, yellow or any other non-black color.

When the optical chip 230 is adhered to the printed circuit board 211 through the black DAF 220 and electrically connected to the printed circuit board 211 through the metal leads, the optical chip 230 forms an electrical signal that can be transmitted to the printed circuit board 211 and transmitted to the processing unit through the printed circuit board 211 to perform related functions. Optionally, the package structure 200 may include the processing unit, which may be similarly disposed and electrically connected to the printed circuit board 211. Alternatively, the processing unit is disposed on a component independent from the package structure 200, and the printed circuit board 211 needs to be connected to the component of the processing unit through an electrical connector.

By way of example, in the embodiment shown in fig. 3, the printed circuit board 211 may be connected to the resident components of the processing unit by means of a flexible circuit board 212.

Optionally, the printed circuit board 211 comprises: a first gold finger 2111; the package structure 200 further includes: a flexible circuit board 212, one end of which is provided with a second gold finger 2121, the second gold finger 2121 being used to be electrically connected to the first gold finger 2111 through an Anisotropic Conductive Film (ACF) 214 to electrically connect the printed circuit board 211 and the flexible circuit board 212.

Further, the other end of the flexible circuit board 212 is provided with a Connector (Connector)2122 to connect to an external electrical component, for example, a component where the processing unit is located. Through the printed circuit board 211 and the flexible circuit board 212, the electrical signal generated by the optical chip 230 can be transmitted to a processing unit for processing, so as to perform corresponding functions.

Optionally, as shown in fig. 3, in order to process and optimize the electrical signals passing through the flexible circuit board 212, auxiliary electrical Components, such as Passive Components (Passive Components)2123 of resistors, capacitors, inductors, etc., may be disposed on the flexible circuit board 212. In addition to the passive components 2123, a Micro Controller Unit (MCU) may be disposed on the flexible circuit board 212 to control the operation of the optical chip 230 and related components.

In order to support the passive components 2123 and the MCU on the flexible circuit board 212, a reinforcing plate 213 is disposed below the flexible circuit board 212 to reinforce the region of the flexible circuit board 212 where the components are disposed. The flexible circuit board 212 can be bent in the area where no component is disposed, and has better flexibility, so as to facilitate the mounting of the flexible circuit board 212 and the connection with other electrical components.

Fig. 4 is a schematic structural diagram of a package structure 200 of another optical chip shown in the embodiment of the present application.

As shown in fig. 4, in the package structure 200, the substrate 210 includes a flexible circuit board 212 and a reinforcing plate 213. The optical chip 230 is adhered to the surface of the flexible circuit board 212 through the black DAF 220 and electrically connected to the flexible circuit board 213. The reinforcing plate 213 is disposed under the flexible circuit board 212 and is adhered to the flexible circuit board 212 by a structural adhesive 215, and the reinforcing plate 213 is used for supporting and reinforcing the flexible circuit board 212 and the optical chip 230.

In the embodiment of the present application, since the package structure 200 is provided with the black DAF 220 to absorb and block the optical signal passing through the optical chip 230, the solder mask layer on the surface of the flexible circuit board 212 may not need to use black solder mask ink, i.e., the solder mask layer on the surface of the flexible circuit board 212 is a non-black solder mask layer, which may be green, white or any other non-black color.

Optionally, in the embodiment of the present application, the electrical connection manner between the optical chip 230 and the flexible circuit board 212 may refer to the electrical connection manner in the embodiment shown in fig. 3 above, that is, the electrical connector 240 in the embodiment of the present application may also be a metal lead, and the optical chip 230 may be connected to the flexible circuit board 212 through the metal lead. Further, the metal leads are covered by the lead protection paste 250 to achieve reliable electrical connection therebetween.

Alternatively, in the embodiment of the present application, in addition to the flexible circuit board 212 electrically connected to the optical chip 230, other components such as a connector 2122 and a passive component 2123 may be disposed on the flexible circuit board 212. The optical chip 230 may be electrically connected to the component where the processing unit is located directly through the flexible circuit board 212, and transmit its formed electrical signal using the flexible circuit board 212.

Compared with the package structure shown in fig. 3, the package structure of the embodiment of the present application does not need to realize the electrical connection between the rigid circuit board 211 and the flexible circuit board 212, and only needs to directly bond the optical chip 230 to the surface of the flexible circuit board 212, so that the overall process is simple, and the production efficiency and the productivity of the package structure can be improved.

Fig. 5 is a schematic structural diagram of a package structure 200 of another optical chip according to an embodiment of the present application.

As shown in fig. 5, in the package structure 200, the substrate 210 includes a flexible circuit board 212 and a reinforcing plate 213. The optical chip 230 is adhered to the surface of the reinforcing plate 213 through the black DAF 220 and electrically connected to the flexible circuit board 213.

Specifically, as shown in fig. 5, the reinforcing plate 213 is disposed below the flexible circuit board 212 and is adhered to the flexible circuit board 212 by a structural adhesive 215, the flexible circuit board 212 has an opening therein, and the optical chip 230 is located in the opening and adhered to the reinforcing plate 213 by a black DAF 220.

By the embodiment, the opening is formed in the flexible circuit board 212 to accommodate the optical chip 230, so that the overall thickness of the package structure 200 can be reduced, and the package structure 200 and the electronic device thereof can be light and thin.

In addition, in this embodiment, since the black DAF 220 is disposed in the package structure 200 to absorb and block the optical signal passing through the optical chip 230, the surface of the reinforcing plate 213 does not need to be subjected to any blackening treatment, i.e., the surface of the reinforcing plate 213 is not coated with the black light blocking layer, and the reinforcing plate 213 may be a silver-white reinforcing steel plate or any other type of reinforcing plate.

Alternatively, similar to the embodiment shown in fig. 4, in the embodiment of the present application, the flexible circuit board 212 may also be electrically connected to the optical chip 230 through a metal lead, and other components such as the connector 2122 and the passive component 2123 may also be disposed on the flexible circuit board 212. The optical chip 230 may be electrically connected to the processing unit via the flexible circuit board 212 directly, and transmit an electrical signal formed by the flexible circuit board 212.

Compared with the package structure shown in fig. 4, the package structure 200 of the present embodiment has a smaller overall thickness, which facilitates the development of the package structure 200 and the electronic device thereof.

The embodiment of the present application further provides an electronic device, which may include a processing unit and the package structure 200 of the optical chip in any of the above embodiments, where the processing unit is configured to receive a detection signal of the optical chip 230 through the substrate 210 and process the detection signal to execute a corresponding function.

As a common application scenario, the optical chip 230 provided in the embodiment of the present application is an optical fingerprint sensor chip, and correspondingly, the package structure 200 provided in the embodiment of the present application is a package structure of an optical fingerprint sensor chip, and the package structure 200 of the optical fingerprint sensor chip may be applied to a smart phone, a tablet computer, and other mobile terminals or other electronic devices with a display screen; more specifically, in the above electronic device, the package structure 200 of the optical fingerprint sensor chip may be disposed in a partial area or an entire area below the display screen, thereby forming an Under-screen (Under-display) optical fingerprint system.

Fig. 6 and 7 illustrate a schematic top-view structure and a schematic cross-sectional structure of an electronic device 10 provided according to an embodiment of the present application.

In an embodiment of the present application, the electronic device 10 includes a display screen 101 and the package structure 200 in any of the above embodiments, wherein the package structure 200 may be disposed in a local area below the display screen 101.

As an example, the package structure 200 shown in fig. 7 may be the same as the package structure 200 shown in fig. 5. In other examples, the package structure 200 shown in fig. 7 may be the same as the package structure 200 shown in any of fig. 2-4 above.

Specifically, in the embodiment of the present application, the optical chip 230 in the package structure 200 is an optical fingerprint sensor chip, the optical fingerprint sensor chip includes a photosensitive array 231 having a plurality of optical sensing units (also called photosensitive units), and a sensing area of the photosensitive array 231 in the display screen 101 is a fingerprint detection area 201 of the package structure 200. As shown in fig. 6, the fingerprint detection area 201 is located in the display area of the display screen 101.

When a user needs to unlock or verify other fingerprints of the electronic device, the user only needs to press a finger on the fingerprint detection area 201 of the display screen 101, and the optical fingerprint sensor chip in the package structure 200 can detect the fingerprint of the user. Since fingerprint detection can be implemented under the screen, the electronic device 10 with the above structure does not need to reserve a space on the front surface thereof specially for setting a fingerprint key (such as a Home key), so that a full-screen scheme can be adopted, that is, the display area of the display screen 101 can be basically extended to the front surface of the whole electronic device 10.

As an alternative implementation, as shown in fig. 7, the package structure 200 may further include an optical component 260 in addition to the optical chip 230. The optical assembly 260 may be correspondingly disposed above the photosensitive array 231, and may specifically include a light guiding layer or a light path guiding structure and other optical elements, where the light guiding layer or the light path guiding structure is mainly used for guiding the reflected light reflected from the surface of the finger to the photosensitive array 231 for optical detection.

In particular implementations, the optical component 260 may be completely encapsulated in the optical chip 230, or at least a portion of the optical component 260 may be disposed outside of the optical chip 230. In some examples, the entirety of the optical component 260 fits over the optical chip 230; or in other examples, some components of the optical assembly 260 are packaged in the optical chip 230, and another component is disposed outside the optical chip 230.

The light guide layer or the light path guide structure of the optical component 260 has various implementation schemes, for example, in an embodiment, the light guide layer may be specifically a Collimator (collimater) layer fabricated on a semiconductor silicon wafer; alternatively, in another embodiment, the light guiding layer or the light path guiding structure may be an optical Lens (Lens) layer having a single Lens or a Lens group formed by a plurality of lenses. Alternatively still, in other embodiments, the light guiding layer or the light path guiding structure may include a Micro-Lens (Micro-Lens) layer having a Micro-Lens array formed by a plurality of Micro-lenses and at least one aperture layer disposed between the Micro-Lens layer and the optical chip 230. Alternatively, the microlens array and the at least one aperture layer may be formed over the photosensitive array 231 of the optical chip 230 by a semiconductor growth process or other processes. Specifically, in at least one aperture layer, each aperture layer includes: the light blocking layer and the diaphragm holes arranged in the light blocking layer, the diaphragm holes in at least one diaphragm layer can form a plurality of light guide channels, each light guide channel can correspond to one photosensitive unit in the photosensitive array 231 and is used for guiding fingerprint light signals passing through fingers and converged by the micro lenses to the photosensitive unit. Optionally, in the microlens array, each microlens may correspond to one light guide channel and one light sensing unit, or each microlens may also correspond to a plurality of light guide channels and a plurality of light sensing units, so as to improve the utilization rate of the fingerprint light signal.

As an alternative embodiment, the display screen 101 may adopt a display screen having a self-luminous display unit, such as an Organic Light-Emitting Diode (OLED) display screen or a Micro-LED (Micro-LED) display screen. Taking the OLED display screen as an example, the package structure 200 may utilize the display unit (i.e., the OLED light source) of the OLED display screen 101 located in the fingerprint detection area 201 as an excitation light source for optical fingerprint detection. When the finger 300 is pressed against the fingerprint detection area 201, the display 101 emits a beam of light 111 toward the target finger 300 above the fingerprint detection area 201, and the light 111 is reflected on the surface of the finger 300 to form reflected light or scattered light by scattering through the inside of the finger 300 to form scattered light, which is collectively referred to as reflected light for convenience of description in the related patent application. Since the ridges (ridges) and the valleys (valley) of the fingerprint have different light reflection capabilities, the reflected light from the ridges and the valleys of the fingerprint have different light intensities, and the reflected light 112 is received by the optical chip 230 in the package structure 200 and converted into corresponding electrical signals, i.e., fingerprint detection signals, after passing through the optical assembly 260. Further, the fingerprint detection signal is transmitted to the processing unit through the substrate 210, and the processing unit can obtain the fingerprint image data based on the fingerprint detection signal, and can further perform fingerprint matching verification, thereby implementing the optical fingerprint identification function in the electronic device 10. By way of example, and not limitation, the processing unit may be a master control unit of the electronic device 10.

In other embodiments, the package structure 200 may also use an internal light source or an external light source to provide an optical signal for fingerprint detection. In this case, the package structure 200 may be suitable for a non-self-luminous Display screen, such as a Liquid Crystal Display (LCD) or other passive luminous Display screen.

It should be understood that in particular implementations, the electronic device 10 also includes a transparent protective cover plate, which may be a glass cover plate or a sapphire cover plate, positioned over the display screen 101 and covering the front face of the electronic device 10. Because, in the present embodiment, the pressing of the finger on the display screen 101 actually means pressing on the cover plate above the display screen 101 or the surface of the protective layer covering the cover plate.

Alternatively, the package structure 200 disposed below the display screen 101 may be fixedly disposed on the display screen 101 according to actual conditions, and/or fixedly disposed on a middle frame of the electronic device 10, where the middle frame is a middle frame of the electronic device 10 and may be used to support various components of the display screen 101, a battery, a main board, and the like in the electronic device 10.

Optionally, a gap may be formed between the display screen 101 and the middle frame, and the package structure 200 in the embodiment of the disclosure may be fixed on a surface of the middle frame facing the display screen 101, so as to be fixedly disposed below the display screen 101. The package structure 200 and the display screen 101 may have a certain distance therebetween to satisfy the optical imaging requirement of the optical chip 230 in the package structure 200.

In addition, the package structure 200 may be disposed on the middle frame, and may also be fixed to the lower surface of the display screen 101 through a foam layer, an adhesive layer, and the like, where the foam layer and the adhesive layer may have a certain thickness, so that a certain distance is formed between the package structure 200 and the display screen 101, so as to meet the optical imaging requirement of the optical chip 230 in the package structure 200.

It should be noted that, the above embodiment of fig. 7 only uses the optical fingerprint system as an example to describe an application scenario of the package structure 200 in the embodiment of the present application, and it should not constitute any limitation to the embodiment of the present application. In addition to optical fingerprint systems, the package structure 200 of the present embodiment is also applicable to other systems using optical imaging or optical detection techniques.

It should be noted that, for convenience of description, like reference numerals denote like parts in the embodiments of the present application, and a detailed description of the like parts is omitted in different embodiments for the sake of brevity. It should be understood that the thickness, length, width and other dimensions of the various components in the embodiments of the present application and the overall thickness, length, width and other dimensions of the integrated device shown in the drawings are only exemplary and should not constitute any limitation to the present application.

It should be understood that the processing unit of the embodiments of the above application, also referred to as a processor, may be an integrated circuit chip having signal processing capabilities. In implementation, the steps of the above method embodiments may be performed by integrated logic circuits of hardware in a processor or instructions in the form of software. The Processor may be a general purpose Processor, a Digital Signal Processor (DSP), an Application Specific Integrated Circuit (ASIC), an off-the-shelf Programmable Gate Array (FPGA) or other Programmable logic device, discrete Gate or transistor logic device, or discrete hardware components.

It should also be understood that the specific examples in the embodiments of the present application are for the purpose of promoting a better understanding of the embodiments of the present application and are not intended to limit the scope of the embodiments of the present application.

Furthermore, the terminology used in the embodiments of the present application and the appended claims is for the purpose of describing particular embodiments only and is not intended to be limiting of the embodiments of the present application. For example, as used in the examples of this application and the appended claims, the singular forms "a," "an," and "the" are intended to include the plural forms as well, unless the context clearly indicates otherwise.

Those of ordinary skill in the art will appreciate that the elements of the examples described in connection with the embodiments disclosed herein may be implemented as electronic hardware, computer software, or combinations of both, and that the components and steps of the examples have been described above generally in terms of their functionality in order to clearly illustrate the interchangeability of hardware and software. Whether such functionality is implemented as hardware or software depends upon the particular application and design constraints imposed on the implementation. Skilled artisans may implement the described functionality in varying ways for each particular application, but such implementation decisions should not be interpreted as causing a departure from the scope of the present application.

In the several embodiments provided in the present application, it should be understood that the disclosed system and apparatus may be implemented in other ways. For example, the above-described apparatus embodiments are merely illustrative, and for example, the division of the units is only one logical division, and other divisions may be realized in practice, for example, a plurality of units or components may be combined or integrated into another system, or some features may be omitted, or not executed. In addition, the shown or discussed mutual coupling or direct coupling or communication connection may be an indirect coupling or communication connection through some interfaces, devices or units, and may also be an electric, mechanical or other form of connection.

The units described as separate parts may or may not be physically separate, and parts displayed as units may or may not be physical units, may be located in one place, or may be distributed on a plurality of network units. Some or all of the units can be selected according to actual needs to achieve the purpose of the solution of the embodiments of the present application.

In addition, functional units in the embodiments of the present application may be integrated into one processing unit, or each unit may exist alone physically, or two or more units are integrated into one unit. The integrated unit can be realized in a form of hardware, and can also be realized in a form of a software functional unit.

The integrated unit, if implemented in the form of a software functional unit and sold or used as a stand-alone product, may be stored in a computer readable storage medium. Based on such understanding, the technical solution of the present application may be substantially or partially contributed by the prior art, or all or part of the technical solution may be embodied in a software product, which is stored in a storage medium and includes instructions for causing a computer device (which may be a personal computer, a server, or a network device) to execute all or part of the steps of the method according to the embodiments of the present application. And the aforementioned storage medium includes: various media capable of storing program codes, such as a usb disk, a removable hard disk, a Read-Only Memory (ROM), a Random Access Memory (RAM), a magnetic disk, or an optical disk.

While the invention has been described with reference to specific embodiments, the scope of the invention is not limited thereto, and those skilled in the art can easily conceive various equivalent modifications or substitutions within the technical scope of the invention. Therefore, the protection scope of the present application shall be subject to the protection scope of the claims.

Claims (14)

1. An optical chip package structure, comprising: the optical chip comprises a substrate, a chip bonding adhesive film and an optical chip;

the chip bonding adhesive film is arranged between the substrate and the optical chip and used for bonding the substrate and the optical chip, the chip bonding adhesive film is a dark chip bonding adhesive film, and the chip bonding adhesive film is also used for absorbing an optical signal penetrating through the optical chip so as to prevent the optical signal from interfering with optical detection of the optical chip after being reflected by the substrate.

2. The package structure of claim 1, wherein the die attach adhesive film is a black die attach adhesive film.

3. The package structure of claim 1, wherein the light transmittance of the die attach adhesive film is less than or equal to 50%.

4. The package structure of claim 1, wherein the gloss of the die attach adhesive film is less than or equal to 200GU at a measurement angle of 60 °.

5. The package structure of claim 1, wherein the die attach adhesive film has a thickness of 10 μm or more and 30 μm or less.

6. The package structure according to any one of claims 1 to 5, wherein the optical chip has a thickness of 300 μm or less.

7. The package structure according to any one of claims 1 to 5, wherein the optical chip is an optical fingerprint sensor chip.

8. The package structure of claim 7, further comprising: a microlens layer and at least one diaphragm layer;

the micro-lens layer comprises a micro-lens array formed by a plurality of micro-lenses;

the optical fingerprint sensor chip comprises a photosensitive array formed by a plurality of photosensitive units;

the at least one diaphragm layer is arranged between the micro-lens layer and the optical fingerprint sensor chip, and each diaphragm layer in the at least one diaphragm layer comprises: the light guide device comprises a light blocking layer and a plurality of diaphragm holes, wherein the diaphragm holes in the at least one diaphragm layer are used for forming a plurality of light guide channels, each light guide channel in the plurality of light guide channels corresponds to one photosensitive unit in the photosensitive array, and each light guide channel is used for transmitting a fingerprint light signal which passes through a finger of a user and is converged by the micro lens to the corresponding photosensitive unit so as to perform fingerprint detection.

9. The package structure according to any one of claims 1 to 5, wherein the substrate comprises a printed circuit board, and the optical chip is adhered to a surface of the printed circuit board by the die attach adhesive film.

10. The package structure according to any one of claims 1 to 5, wherein the substrate includes a flexible circuit board and a stiffener, the optical chip is bonded to a surface of the flexible circuit board by the die attach adhesive film, and the stiffener is configured to support and reinforce the flexible circuit board and the optical chip.

11. The package structure according to any one of claims 1 to 5, wherein the substrate comprises a flexible circuit board and a stiffener, the flexible circuit board has an opening therein, the optical chip is located in the opening and is bonded to the stiffener by the die attach adhesive film, and the stiffener is used for supporting and reinforcing the flexible circuit board and the optical chip.

12. The package structure according to any one of claims 1 to 5, further comprising: the optical chip comprises a metal lead and lead protection glue, wherein the metal lead is used for electrically connecting the optical chip and the substrate, and the lead protection glue covers the metal lead and is used for supporting and protecting the metal lead.

13. An electronic device, comprising: a processing unit for receiving the detection signal of the optical chip through the substrate and processing the detection signal, and the package structure of the optical chip according to any one of claims 1 to 12.

14. The electronic device of claim 13, further comprising: the display screen, the optics chip is optics fingerprint sensor chip, optics fingerprint sensor chip set up in the display screen below.

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