CN111639532A - Optical fingerprint module, manufacturing method thereof and electronic equipment - Google Patents
Optical fingerprint module, manufacturing method thereof and electronic equipment Download PDFInfo
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- CN111639532A CN111639532A CN202010346302.XA CN202010346302A CN111639532A CN 111639532 A CN111639532 A CN 111639532A CN 202010346302 A CN202010346302 A CN 202010346302A CN 111639532 A CN111639532 A CN 111639532A
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- G—PHYSICS
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- G06V—IMAGE OR VIDEO RECOGNITION OR UNDERSTANDING
- G06V40/00—Recognition of biometric, human-related or animal-related patterns in image or video data
- G06V40/10—Human or animal bodies, e.g. vehicle occupants or pedestrians; Body parts, e.g. hands
- G06V40/12—Fingerprints or palmprints
- G06V40/13—Sensors therefor
- G06V40/1318—Sensors therefor using electro-optical elements or layers, e.g. electroluminescent sensing
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- H01L27/00—Devices consisting of a plurality of semiconductor or other solid-state components formed in or on a common substrate
- H01L27/14—Devices consisting of a plurality of semiconductor or other solid-state components formed in or on a common substrate including semiconductor components sensitive to infrared radiation, light, electromagnetic radiation of shorter wavelength or corpuscular radiation and specially adapted either for the conversion of the energy of such radiation into electrical energy or for the control of electrical energy by such radiation
- H01L27/144—Devices controlled by radiation
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Abstract
The invention provides an optical fingerprint module, a manufacturing method thereof and electronic equipment. Optical fingerprint module includes optical fingerprint sensor chip, light guide component and filtering component. The optical fingerprint sensor chip comprises a first surface with a photosensitive device area, a second surface arranged opposite to the first surface, and a through hole penetrating through the first surface and the second surface, wherein the through hole is provided with a conductive material used for transmitting a sensing signal of the photosensitive device area to the second surface. The light guide element is arranged on one side where the first surface of the optical fingerprint sensor chip is located. The light filtering element is located between the first surface and the light guide element, covers and is attached to the first surface through the surface adhesive layer, and is used for filtering interference light of the guide light of the light guide element. The light filtering element and the light guide element are hung on the first surface of the optical fingerprint sensor chip adopting the through hole technology through the surface adhesive layer, so that the yield loss of the chip can be reduced, and the light leakage caused by chip welding can be improved.
Description
Technical Field
The invention relates to the technical field of fingerprint identification, in particular to an optical fingerprint module, a manufacturing method thereof and electronic equipment adopting the optical fingerprint module.
Background
With the rapid development of various electronic devices (such as mobile phones, tablet computers, notebook computers, etc.), users have made more functional demands on the electronic devices. Fingerprint identification technology is widely applied to electronic equipment due to the privacy protection function, so as to increase the user experience. Fingerprint identification techniques can be classified into optical, capacitive, acoustic, and the like. In the optical fingerprint identification technology, fingerprint identification is generally achieved by collecting and analyzing emitted light formed by light emitted by a light source and reflected by a finger. In recent two years, electronic equipment has entered the full screen era, and the optical fingerprint module is more and more emphasized because can set up and realize fingerprint discernment under the screen below the display screen.
In the related art, as shown in fig. 1, the optical module 100 may include a circuit board 110, an optical fingerprint sensor chip 120 disposed on the circuit board 110, and an optical microlens structure 130 and a filter element 140 integrated on the optical fingerprint sensor chip 120 for guiding light. The surface of the optical fingerprint sensor chip 120 adjacent to the optical microlens structure 130 has a photosensitive device region 122 corresponding to the optical microlens structure 130 and an edge region 126 located at the periphery of the photosensitive device region 122. The edge region 126 can be electrically connected to the circuit board 110 through a metal bonding wire 150 manufactured by a cob (chip On board) process, and a sensing signal of the photo sensor region 122 can be transmitted to the circuit board 110 through the edge region 126 and the metal bonding wire 150. In the course of implementing the present invention, the inventor found that integrating the optical microlens structure 130 and the filter element 140 on the optical fingerprint sensor chip 120 may cause yield loss of the optical fingerprint module due to the optical microlens process, and in addition, the plane size of the optical fingerprint module 100 of the related art is difficult to shrink, which may cause light leakage problem of the module.
Disclosure of Invention
In view of the above, it is desirable to provide an optical fingerprint module, a method for manufacturing the same, and an electronic device using the optical fingerprint module.
In a first aspect, an embodiment of the present invention provides an optical fingerprint module, which includes an optical fingerprint sensor chip, a light guide element, and a filter element. The optical fingerprint sensor chip comprises a first surface with a photosensitive device area, a second surface arranged opposite to the first surface, and a through hole penetrating through the first surface and the second surface, wherein a conductive material used for transmitting a sensing signal of the photosensitive device area to the second surface is arranged in the through hole. The light guide element is arranged on one side of the first surface of the optical fingerprint sensor chip. The light guide element is formed on the light filtering element, the light filtering element is located between the first surface and the light guide element, the light filtering element is covered and attached to the first surface through a surface adhesive layer, and the light filtering element is used for filtering interference light of the guide light of the light guide element and then providing the interference light to the photosensitive device area.
In the optical fingerprint module provided by the embodiment of the invention, the optical filtering element and the optical guiding element are externally hung on the first surface of the optical fingerprint sensor chip adopting the through hole technology through the surface adhesive layer, so that the chip yield loss caused by integrating the optical guiding element and the optical filtering element on the optical fingerprint sensor chip can be avoided. In addition, the optical fingerprint sensor chip adopts a through hole technology, so that the optical filtering element is conveniently adhered to the second surface of the optical fingerprint sensor chip through the surface adhesive layer, and the surface adhesive layer can also keep better fixed strength between the optical filtering element and the optical fingerprint sensor chip, thereby improving the overall strength of the optical fingerprint module; in addition, the edge area of the first surface of the optical fingerprint sensor chip is not required to be electrically connected with other external circuit devices by using metal bonding wires, but can be electrically connected with other external circuit devices by the second surface, so that the edge area can be removed or reduced, and the light leakage problem of a module can be improved.
In addition, because the sensing signal of the photosensitive device region is transmitted to the second surface through the through hole technology, the edge region of the first surface of the optical fingerprint sensor chip except the photosensitive device region can be removed or set to be smaller in size, and then the plane size of the optical fingerprint module can be smaller, and the area of the photosensitive device region can be higher.
Further, in the optical fingerprint module of one embodiment, the filter element includes a substrate and a filter film disposed on at least one side of the substrate; the light guide element comprises a plurality of optical micro lenses and a light shielding layer positioned between every two adjacent optical micro lenses, and the optical micro lenses are formed on the surface, far away from the optical fingerprint sensor chip, of the light filtering element through an embossing process. The filter coating can filter stray light, improves the formation of image effect of optics fingerprint module. Because the light guide element also does not need to be provided with a base material, the thickness of the whole device is not large, and the light guide element and the light filtering element can be combined closely, so that the reliability of the optical fingerprint module is ensured.
In an embodiment of the optical fingerprint module, the filter element includes a first filter film located between the substrate and the plurality of optical microlenses and a second filter film located on a side of the substrate adjacent to the first surface, the surface of the first filter film away from the substrate forms the plurality of optical microlenses, and the surface of the second filter film away from the substrate is covered and attached to the first surface through the surface adhesive layer. The arrangement of the first and second light filtering films can achieve a good light filtering effect, and the phenomenon that interference light enters the photosensitive device area to influence fingerprint identification is reduced.
In the optical fingerprint module of one embodiment, the optical fingerprint module further includes a circuit board located on a side where the second surface of the optical fingerprint sensor chip is located, and a conductive body located between the circuit board and the second surface, and the conductive body is configured to transmit a sensing signal transmitted by a conductive material of the through hole to the circuit board. The conductive material of the through hole and the sensing signal transmitted by the second surface are transmitted to the circuit board through the conductor, so that the edge area can be removed or reduced, and module light leakage is improved.
In a second aspect, an embodiment of the present invention provides a method for manufacturing an optical fingerprint module, including the following steps:
providing a filter element;
forming a light guide element on the surface of the filter element, wherein the filter element is used for filtering interference light of the guide light of the light guide element;
providing an optical fingerprint sensor chip, wherein the optical fingerprint sensor chip comprises a first surface with a photosensitive device area, a second surface arranged opposite to the first surface and a through hole penetrating through the first surface and the second surface, and the through hole is internally provided with a conductive material for transmitting a sensing signal of the photosensitive device area to the second surface; and
the surface of the light filtering element far away from the light guide element is covered and attached to the first surface through a surface adhesive layer.
In the method for manufacturing the optical fingerprint module, the optical filter element and the optical guide element are externally attached to the first surface of the optical fingerprint sensor chip adopting the through hole technology through the surface adhesive layer, so that the chip yield loss caused by integrating the optical guide element and the optical filter element on the optical fingerprint sensor chip can be avoided, and the problems of low efficiency and low productivity caused by sequential manufacturing can be avoided as the optical filter element, the optical guide element and the optical fingerprint sensor chip can be separately manufactured and then attached through the surface adhesive layer.
In addition, because the optical fingerprint sensor chip adopts the through hole technology, the optical filtering element is conveniently pasted on the second surface of the optical fingerprint sensor chip through the surface adhesive layer, and the surface adhesive layer can also ensure that the optical filtering element and the optical fingerprint sensor chip keep better fixed strength, so that the overall strength of the optical fingerprint module is improved, in addition, the edge area of the first surface of the optical fingerprint sensor chip is not required to be electrically connected with other external circuit devices through a metal bonding wire, but can be electrically connected with other external circuit devices through the second surface, so that the edge area can be removed or reduced, and the light leakage module can be improved.
In addition, as the sensing signal of the photosensitive device region is transmitted to the second surface through the through hole technology, the edge region of the first surface of the optical fingerprint sensor chip except the sensing device region can be removed or reduced, and further the plane size of the optical fingerprint module obtained by the manufacturing method can be smaller, and the plane area ratio of the photosensitive device region can be higher.
In one embodiment of the method for manufacturing an optical fingerprint module, the step of providing the filter element includes: providing a substrate; and carrying out evaporation or sputtering on the surface of the substrate to form a first filter film, wherein the surface of the first filter film, which is far away from the substrate, forms the light guide element. The first filter film is formed on the surface of the substrate through evaporation or sputtering, the light guide element is formed on the surface, far away from the substrate, of the first filter film, and further the light guide element is not required to be provided with the substrate, so that the thickness of the whole device is small, the light guide element and the filter element can be combined tightly, and the reliability of the optical fingerprint module is guaranteed.
In an embodiment of the method for manufacturing an optical fingerprint module, the step of providing the filter element further includes: and forming a second filter film on the surface of the substrate far away from the first filter film by evaporation or sputtering, wherein the surface of the second filter film far away from the substrate is in covering fit with the first surface of the optical fingerprint sensor chip through the surface adhesive layer. Through evaporation plating or sputtering are in the substrate is kept away from the surface of first filter coating forms the second filter coating, the second filter coating is kept away from the surface of substrate is passed through the face glue film with the laminating is covered to the first surface of optics fingerprint sensor chip, first and second filter coating set up and also can reach better filter effect, reduce interference light and enter the regional phenomenon that leads to influencing fingerprint identification of sensitization device takes place. In addition, the first and second filter films are formed in the same evaporation or sputtering step, so that the manufacturing method of the optical fingerprint module is high in efficiency.
In one embodiment of the method for manufacturing an optical fingerprint module, the step of forming the light guide element on the surface of the filter element includes:
forming an optical microlens material layer on the surface of the first filter film, which is far away from the substrate;
embossing and photocuring the optical microlens material layer to form a plurality of optical microlenses;
depositing a shading material layer on one side of the optical micro lenses far away from the first filter film; and
and carrying out photomask exposure development on the shading material layer so that a shading layer is formed between the adjacent optical micro lenses and at least part of the plurality of optical micro lenses is exposed to receive light.
The light shading layer is formed by impressing and photocuring the optical microlens material layer to form a plurality of optical microlenses and exposing and developing the light shading material layer, and further the optical microlenses and the light shading layer do not need to be provided with a base material, so that the thickness of the whole device is small, the first light filtering film is tightly combined with the optical microlenses and the light shading layer, and the reliability of the optical fingerprint module is guaranteed.
In the method for manufacturing an optical fingerprint module according to one embodiment of the present invention, the method for manufacturing an optical fingerprint module further includes the following steps before the step of adhering the surface of the filter element away from the light guide element to the first surface by the adhesive surface layer:
providing a conductor and a circuit board;
arranging the conductor on the second surface of the optical fingerprint sensor chip by a ball planting process; and
the second surface of the optical fingerprint sensor chip is electrically connected with the circuit board through the electric conductor by a reflow soldering process, so that the sensing signal of the photosensitive device area can be transmitted to the circuit board through the electric conductor and the electric conductive material in the through hole.
Specifically, before the step of covering and attaching the surface of the filter element far away from the light guide element to the first surface through the surface adhesive layer, the second surface of the optical fingerprint sensor chip is electrically connected with the circuit board through an electric conductor by using a ball-planting and reflow soldering process, so that the reliability of the electrical connection can be ensured, and the conductive material of the through hole and the sensing signal transmitted by the second surface are transmitted to the circuit board through the electric conductor, so that the edge area can be removed or reduced, and the module light leakage can be improved. In addition, the second surface of the optical fingerprint sensor chip is firstly electrically connected with the circuit board and then is covered and attached with the filter element through the surface adhesive layer, so that the filter element and the light guide element can be prevented from being damaged by ball planting and reflow soldering processes, and the filter element and the light guide element can be prevented from influencing the ball planting and reflow soldering processes.
In a third aspect, an embodiment of the present invention provides an electronic device, which includes the optical fingerprint module according to any one of the above embodiments. Specifically, in the electronic device of the embodiment, the optical filter element and the light guide element are externally hung on the first surface of the optical fingerprint sensor chip adopting the through hole technology through the surface adhesive layer, so that the chip yield loss caused by integrating the light guide element and the optical filter element on the optical fingerprint sensor chip can be avoided. In addition, the optical fingerprint sensor chip adopts a through hole technology, so that the optical filtering element is conveniently adhered to the second surface of the optical fingerprint sensor chip through the surface adhesive layer, and the surface adhesive layer can also keep better fixed strength between the optical filtering element and the optical fingerprint sensor chip, thereby improving the overall strength of the optical fingerprint module; in addition, the edge area of the first surface of the optical fingerprint sensor chip is not required to be electrically connected with other external circuit devices by using metal bonding wires, but can be electrically connected with other external circuit devices by the second surface, so that the edge area can be removed or reduced, and the light leakage problem of a module can be improved. In addition, because the sensing signal of the photosensitive device region is transmitted to the second surface through the through hole technology, the edge region of the first surface of the optical fingerprint sensor chip except the photosensitive device region can be removed or set to be smaller in size, and then the plane size of the optical fingerprint module can be smaller, and the area of the photosensitive device region can be higher.
In one embodiment of the electronic device, the filter element includes a substrate and a filter film disposed on at least one side of the substrate; the light guide element comprises a plurality of optical micro lenses and a light shielding layer positioned between every two adjacent optical micro lenses, and the optical micro lenses are formed on the surface, far away from the optical fingerprint sensor chip, of the light filtering element through an embossing process. The filter coating can filter stray light, improves the formation of image effect of optics fingerprint module. Because the light guide element also does not need to be provided with a base material, the thickness of the whole device is not large, and the light guide element and the light filtering element can be combined closely, so that the reliability of the optical fingerprint module is ensured.
In an embodiment of the electronic device, the filter element includes a first filter film located between the substrate and the plurality of optical microlenses and a second filter film located on a side of the substrate adjacent to the first surface, the plurality of optical microlenses are formed on a surface of the first filter film away from the substrate, and a surface of the second filter film away from the substrate is covered and attached to the first surface through the surface adhesive layer. The arrangement of the first and second light filtering films can achieve a good light filtering effect, and the phenomenon that interference light enters the photosensitive device area to influence fingerprint identification is reduced.
In the electronic device according to one embodiment of the present invention, the optical fingerprint module further includes a circuit board located on a side where the second surface of the optical fingerprint sensor chip is located, and a conductive body located between the circuit board and the second surface, and the conductive body is configured to transmit a sensing signal transmitted by a conductive material of the through hole to the circuit board. The conductive material of the through hole and the sensing signal transmitted by the second surface are transmitted to the circuit board through the conductor, so that a metal welding wire can be avoided, the edge area can be removed or reduced, and the light leakage of the module can be improved.
Drawings
In order to more clearly illustrate the embodiments of the present invention or technical solutions in related arts, the drawings used in the description of the embodiments or related arts will be briefly introduced below, it is obvious that the drawings in the following description are only embodiments of the present invention, and for those skilled in the art, other drawings can be obtained according to the provided drawings without creative efforts.
Fig. 1 is a schematic cross-sectional view of an optical fingerprint module according to the related art.
Fig. 2 is a schematic cross-sectional view of an optical fingerprint module according to an embodiment of the invention.
FIG. 3 is a flowchart illustrating a method for manufacturing an optical fingerprint module according to an embodiment of the invention.
Fig. 4 is a schematic cross-sectional view of a filter element in the method for manufacturing the optical fingerprint module shown in fig. 3.
Fig. 5 is a schematic cross-sectional view illustrating a filter element and a light guide element in the method for manufacturing the optical fingerprint module shown in fig. 3.
Fig. 6 is a schematic cross-sectional view of the optical fingerprint sensor chip, the conductor and the circuit board before being electrically connected in the manufacturing method of the optical fingerprint module shown in fig. 3.
Fig. 7 is a schematic cross-sectional view illustrating a cross-sectional structure of the optical fingerprint sensor chip and the conductor in the method for manufacturing the optical fingerprint module shown in fig. 3 after the optical fingerprint sensor chip and the conductor are electrically connected.
Fig. 8 is a schematic cross-sectional structure diagram of the optical fingerprint sensor chip, the conductor and the circuit board in the manufacturing method of the optical fingerprint module shown in fig. 3 after being electrically connected.
FIG. 9 is a flowchart of one embodiment of the method of manufacturing the optical fingerprint module of FIG. 3.
Detailed Description
To facilitate an understanding of the invention, the invention will now be described more fully with reference to the accompanying drawings. Preferred embodiments of the present invention are shown in the drawings. This invention may, however, be embodied in many different forms and should not be construed as limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete.
It will be understood that when an element is referred to as being "secured to" another element, it can be directly on the other element or intervening elements may also be present. When an element is referred to as being "connected" to another element, it can be directly connected to the other element or intervening elements may also be present. The terms "inner", "outer", "left", "right" and the like as used herein are for illustrative purposes only and do not represent the only embodiments.
Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. The terminology used in the description of the invention herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention. As used herein, the term "and/or" includes any and all combinations of one or more of the associated listed items.
As shown in fig. 2, the optical fingerprint module 200 according to an embodiment of the present invention can be applied to an electronic device. Specifically, electronic equipment can include optics fingerprint module 200, and optics fingerprint module 200 can set up and realize fingerprint identification under the screen in the display area below of electronic equipment's display screen. More specifically, in the embodiment of the present invention, the electronic device may be a portable intelligent terminal device such as a smart phone, a notebook computer, a tablet computer, a personal computer, an electronic book reader, a Portable Multimedia Player (PMP), a mobile medical device, and a wearable device, and may also be an access control device having a fingerprint identification function, a financial terminal device for depositing and paying, and the like. The optical fingerprint module 200 includes a circuit board 210, a conductive body 260, an optical fingerprint sensor chip 220, a surface adhesive layer 250, a filter element 240, and a light guide element 230.
In this embodiment, the optical fingerprint sensor chip 220 includes a first surface 222 having a photosensitive device region 222a, a second surface 224 opposite to the first surface 222, and a through hole penetrating the first surface 222 and the second surface 224. The via 226 has therein a conductive material 228 for transmitting a sensing signal of the photo-sensing device region 222a to the second surface 224. The Through Hole 226 may be a Through-Silicon-Hole (TSV) penetrating Through the optical fingerprint sensor chip 220. The light guide element 230 is disposed on a side of the first surface 222 of the optical fingerprint sensor chip 220, and the light guide element 230 is used for guiding incident light (such as light reflected by a finger) to the photosensitive device region 222a via the filter element 240. The light guide element 230 is formed on the filter element 240, the filter element 240 is located between the first surface 222 and the light guide element 230, the filter element 240 is covered and attached to the first surface 222 through the surface adhesive layer 250, and the filter element 240 is used for filtering interference light from the guide light of the light guide element 230 and then providing the interference light to the light sensing device region 222 a. Specifically, as shown in fig. 2, the filter element 240 can be attached to the first surface 222 by the surface adhesive layer 250 in a full-coverage manner, and it can be understood that the filter element 240 and the first surface 222 have the largest overlapping coverage area by the full-coverage attachment. However, it is understood that in some embodiments, the ratio of the overlapping coverage of the area of the filter element 240 and the first surface may also be controlled, for example, 80% of the coverage is attached, that is, 80% of the area of the filter element 240 is attached to the first surface 222 through the surface adhesive layer 250, or 80% of the area of the first surface 222 is attached to the filter element 240 through the surface adhesive layer 250.
Specifically, in the optical fingerprint sensor chip 220, the photosensitive device region 222a may cover a substantial portion of the first surface 222, such that the area of the photosensitive device region 222a on the first surface 222 is relatively high. The photo-sensing device region 222a may have a plurality of photo-sensing units for receiving light and generating an electrical sensing signal. The plurality of light sensing units may be arranged in an array, and each light sensing unit may include a photodiode for converting received light into an electrical signal. In this embodiment, the optical fingerprint sensor chip 220 may use a flip-chip through silicon via technology, and the via 226 may be formed through an etching process. The conductive material 228 can be a conductive metal layer, and the conductive material 228 can cover the sidewall and the bottom of the via 226 and electrically connect to the photo-sensing unit on the photo-sensing device region 222a at the first surface 222. The conductive body 260 on the second surface 224 is connected to the circuit board 210, and the sensing signal of the photo sensor device region 222a can be transmitted to the second surface 224 via the conductive material 228 in the through hole 226, and further transmitted to the circuit board 210 via the conductive body 260. It is understood that the second surface 224 may also be formed with conductive traces, and the conductive material 228 in the via 226 may be electrically connected to the conductive body 260 through the conductive traces of the second surface 224.
The number of the conductive bodies 260 may be plural, and the conductive bodies 260 may be conductive particles such as conductive metal balls, for example, solder balls. Specifically, the conductive body 260 may be disposed on the second surface 224 through a ball-bonding process (solder bumping) and then connected to the surface 212 of the circuit board 210 through a solder reflow process, but the present invention is not limited thereto, and the conductive body 260 may be disposed on the surface 212 of the circuit board 210 first and then connected to the second surface 224 through a solder reflow process.
The circuit board 210 may be a flexible circuit board, and the surface 212 of the circuit board 210 may have metal wires connected to the conductive bodies 260 to receive the sensing signals transmitted by the conductive bodies 260. The circuit board 210 may also be electrically connected to other circuit boards of the electronic device (e.g., a printed circuit board) to transmit the sensing signal to other circuit boards of the electronic device.
The filter device 240 includes a substrate 242, a first filter 244 disposed on a side of the substrate 242 adjacent to the light guide 230, and a second filter 246 disposed on a side of the substrate 242 adjacent to the first surface 222. The surface of the second filter 246 away from the substrate 242 may be attached to the first surface 222 by a topcoat layer 250. The second light-shielding film 246 and the surface adhesive layer 250 can substantially completely cover the first surface 222, thereby achieving full coverage. Specifically, the planar size of the filter element 240 may be substantially the same as the planar size of the optical fingerprint sensor chip 220, and thus the planar size of the second filter 246 may be substantially the same as the planar size of the first surface 224, and then the second filter 246 may be substantially aligned with the first surface 224 and adhered to the first surface 222 through the adhesive layer 250.
The material of the substrate 242 includes, but is not limited to, a glass material and a resin material, wherein the resin material may include a polyester resin material (PET) and/or a cyclic olefin polymer material (COP). It will be appreciated that the light transmittance and refractive index of the substrate 242 should meet the requirements of the optical fingerprint design. The first and second filter films 244 and 246 can be both infrared cut filter films, but are not limited to the above, and the first and second filter films 244 and 246 can be formed by performing evaporation or sputtering on the front and back surfaces of the substrate 242. In other embodiments, the filter element 240 may also be provided with a filter on one side, such as the first filter 244 or the second filter 246, and the filter can be specifically provided according to actual needs.
The surface Adhesive layer 250 may be a Die Attach Film (DAF) and an optical Adhesive (OCA), but is not limited thereto. Specifically, the surface adhesive layer 250 may be coated on at least one of the surface of the second filter film 246 away from the substrate 242 and the first surface 222, and then the filter element 240 and the optical fingerprint sensor chip 220 are bonded together.
The light guiding element 230 includes a plurality of optical microlenses 232 and a light shielding layer 234 located between two adjacent optical microlenses 232 and at least partially exposing the plurality of optical microlenses 232. In this embodiment, the plurality of optical microlenses 232 may be formed on the surface of the first filter 244 away from the substrate 242 by a stamping process, specifically, a layer of optical microlens material may be coated on the surface of the first filter 244 away from the substrate 242, and then the plurality of optical microlenses 232 are formed by stamping and photo-curing (e.g., uv irradiation curing). The plurality of optical microlenses 232 may be arranged in an array. Each of the optical micro-lenses 232 may correspond to one of the light sensing units of the light sensing device region 222a, and is configured to receive light and guide the light to the corresponding one of the light sensing units via the filter element 240. It is understood that the plurality of optical microlenses 232 can have an optical refractive index and a light transmittance that meet the requirements of the optical fingerprint identification technology, and the optical microlenses 232 can have a curvature and a height that are in accordance with the requirements of the optical fingerprint identification technology, so that the light received by the optical microlenses 232 is focused to the corresponding photosensitive cells of the photosensitive device region 222 a.
The light shielding layer 234 exposes a central region of the optical microlens 232 and is used to shield light emitted between two adjacent optical microlenses 232, so as to prevent crosstalk between adjacent light sensing units caused by large-angle stray light entering the light sensing device region 222 a. The light-shielding layer 234 may be formed by depositing a light-shielding material layer on the surfaces of the optical microlenses 232 away from the filter element 240 by spin coating, evaporation, sputtering, or the like, and exposing and developing through a mask such that a portion of the light-shielding material layer between adjacent optical microlenses 232 remains to form the light-shielding layer 234, and at least a portion (e.g., a central region) of the light-shielding material layer of the plurality of optical microlenses 232 is removed and exposed for receiving light.
In the optical fingerprint module 200 and the electronic device having the optical fingerprint module 200 according to the embodiments of the present invention, the optical filter element 240 and the optical guide element 230 are externally hung on the first surface 222 of the optical fingerprint sensor chip 220 using the through-hole technology through the surface adhesive layer 250, so that the chip yield loss caused by integrating the optical guide element and the optical filter element on the optical fingerprint sensor chip can be avoided.
In addition, since the optical fingerprint sensor chip 220 adopts the through hole technology, the filter element 240 can be conveniently covered and attached to the first surface 222 of the optical fingerprint sensor chip 220 through the surface adhesive layer 250, and the surface adhesive layer 250 can also keep better fixing strength between the filter element 240 and the optical fingerprint sensor chip 220, so that the reliability of the optical fingerprint module 200 is improved; moreover, the edge area of the first surface 222 of the optical fingerprint sensor chip 220 does not need to be electrically connected to other external circuit devices by using metal bonding wires, but can be electrically connected to other external circuit devices (such as the circuit board 210) through the second surface 224, so that the edge area can be removed or reduced and the module light leakage problem can be improved.
In addition, since the sensing signal of the photo sensor region 222a is transmitted to the second surface 224 by the through hole technology, the first surface 222 of the optical fingerprint sensor chip 220 may not have an edge region or an edge region with a smaller size except the photo sensor region 222a, and thus the planar size of the optical fingerprint module 200 may be smaller and the planar area ratio of the photo sensor region 222a may also be higher.
Further, the filter element 240 includes a substrate 242 and a first filter 244 located on a side of the substrate 242 adjacent to the light guide element 230, and the plurality of optical micro lenses 232 of the light guide element 230 are formed on a surface of the first filter 244 away from the substrate 242 by a stamping process, so that the light guide element 230 does not need to be provided with a substrate, the thickness of the whole device is not large, and the light guide element 230 and the filter element 240 can be combined tightly, thereby ensuring the reliability of the optical fingerprint module 200.
Furthermore, the light filtering element 240 further includes a second light filtering film 246 disposed on a side of the substrate 242 adjacent to the first surface 222, the second light filtering film 246 is covered and attached to the first surface 222 through a surface adhesive layer 250, and the arrangement of the first and second light filtering films 244 and 246 can achieve a better light filtering effect, so as to reduce the phenomenon that the interference light enters the photo-sensing device region 222a to affect the fingerprint identification.
Further, the optical fingerprint module 200 further includes a circuit board 210 located on the side of the second surface 224 of the optical fingerprint sensor chip 220 and a conductive body 260 located between the circuit board 210 and the second surface 224, and the conductive material 228 of the through hole 226 and the sensing signal transmitted by the second surface 224 are transmitted to the circuit board 210 through the conductive body 260, so that a metal bonding wire can be avoided, the edge area can be further removed or reduced, and the module light leakage problem can be improved.
As shown in fig. 3, an embodiment of the invention further provides a method for manufacturing an optical fingerprint module. The optical fingerprint module 200 shown in fig. 2 can be obtained by the manufacturing method of the optical fingerprint module. However, it is understood that the optical fingerprint module manufacturing method is only one manufacturing method of the optical fingerprint module 200, and may include the following steps S310, S320, S330 and S340.
In step S310, a filter element is provided.
Step S320, forming a light guiding element on a surface of the light filtering element, where the light guiding element is used to receive light and guide the received light to the photosensitive device region via the light filtering element, and the light filtering element is used to filter out interference light from the guided light of the light guiding element.
Step S330, providing an optical fingerprint sensor chip, wherein the optical fingerprint sensor chip comprises a first surface with a photosensitive device area, a second surface arranged opposite to the first surface, and a through hole penetrating through the first surface and the second surface, and the through hole is provided with a conductive material for transmitting a sensing signal of the photosensitive device area to the second surface.
Step S340, covering and adhering the surface of the filter element far from the light guide element to the first surface through a surface adhesive layer.
Specifically, in step S310, as shown in fig. 4, the filter element 240 may include a substrate 242, a first filter 244 located on a side of the substrate 242 adjacent to the light guide element 240, and a second filter 246 located on a side of the substrate 242 adjacent to the first surface 222. The material of the substrate 242 includes, but is not limited to, a glass material and a resin material, wherein the resin material may include a polyester resin material (PET) and/or a cyclic olefin polymer material (COP). It will be appreciated that the light transmittance and refractive index of the substrate 242 should meet the requirements of the optical fingerprint design. The first filter 244 and the second filter 246 can be both infrared cut filters, but are not limited to the above.
Specifically, step S310 may include the steps of:
providing a substrate 242; and
a first filter 244 is formed on the surface of the substrate 242 by evaporation or sputtering, and the light guide element 230 is formed on the surface of the first filter 244 away from the substrate 242.
More specifically, step S310 may further include the steps of: a second filter film 246 is formed on the surface of the substrate 242 away from the first filter film 244 by evaporation or sputtering, wherein the surface of the second filter film 246 away from the substrate 242 is used for covering and attaching the optical fingerprint sensor chip 220 on the first surface 222 through a surface adhesive layer 250.
It is understood that the filter element 240 can be attached to the first surface 222 by the face adhesive layer 250 in a full-covering manner, and it is understood that the filter element is attached by the full-covering manner. Moreover, the filter element 240 and the first surface 222 have the largest overlapping coverage area by full coverage bonding. However, it is understood that in some embodiments, the ratio of the overlapping coverage of the area of the filter element 240 and the first surface may also be controlled, for example, 80% of the coverage is attached, that is, 80% of the area of the filter element 240 is attached to the first surface 222 through the surface adhesive layer 250, or 80% of the area of the first surface 222 is attached to the filter element 240 through the surface adhesive layer 250. The first filter 244 and the second filter 246 can be formed in the same evaporation or sputtering process or in different evaporation or sputtering processes. However, it is understood that the steps of the method for manufacturing the optical fingerprint module are simplified when the first filter 244 and the second filter 246 can be formed in the same evaporation or sputtering process.
Specifically, in step S320, as shown in fig. 5, fig. 5 is a schematic cross-sectional structure diagram of the optical filter element 240 and the optical guiding element 230 in the manufacturing method of the optical fingerprint module shown in fig. 3, which are combined together. The light guiding element 230 includes a plurality of optical microlenses 232 and a light shielding layer 234 located between two adjacent optical microlenses 232 and at least partially exposing the plurality of optical microlenses 232. The plurality of optical microlenses 232 can be formed on the surface of the first filter 244 away from the substrate 242 by a stamping process, and specifically, a layer of optical microlens material can be coated on the surface of the first filter 244 away from the substrate 242, and then the plurality of optical microlenses 232 can be formed by stamping and photocuring (e.g., uv irradiation curing). The plurality of optical microlenses 232 may be arranged in an array. Each of the optical micro-lenses 232 may correspond to one of the light-sensing units of the light-sensing device region 222a, and is configured to receive light (e.g., light reflected by a finger) and guide the light to the corresponding one of the light-sensing units via the filter element 240. It is understood that the plurality of optical microlenses 232 can have an optical refractive index and a light transmittance that meet the requirements of the optical fingerprint identification technology, and the optical microlenses 232 can have a curvature and a height that are in accordance with the requirements of the optical fingerprint identification technology, so that the light received by the optical microlenses 232 is focused to the corresponding photosensitive cells of the photosensitive device region 222 a.
The light shielding layer 234 exposes a central region of the optical microlens 232 and is used to shield light emitted between two adjacent optical microlenses 232, so as to prevent crosstalk between adjacent light sensing units caused by large-angle stray light entering the light sensing device region 222 a.
The light-shielding layer 234 may be formed by depositing a light-shielding material layer on the surfaces of the optical microlenses 232 away from the filter element 240 by spin coating, evaporation, sputtering, or the like, and exposing and developing through a mask such that a portion of the light-shielding material layer between adjacent optical microlenses 232 remains to form the light-shielding layer 234, and at least a portion (e.g., a central region) of the light-shielding material layer of the plurality of optical microlenses 232 is removed and exposed for receiving light.
More specifically, in some embodiments, step S320 may include the steps of:
forming a layer of optical microlens material on the surface of the first filter 244 away from the substrate 242;
imprinting and photocuring the layer of optical microlens material to form a plurality of optical microlenses 232;
depositing a light-shielding material layer on the surface of the plurality of optical microlenses 242 away from the first filter 244; and
the light-shielding material layer is exposed to light and developed such that a light-shielding layer 234 is formed between adjacent optical microlenses 232 and at least a portion of the plurality of optical microlenses 232 is exposed to receive light.
Specifically, in step S330, as shown in fig. 6, 7 and 8, step S330 may further include the following steps:
providing a conductor 260 and a circuit board 210;
disposing the conductive body 260 on the second surface 224 of the optical fingerprint sensor chip 220 through a ball-planting process; and
the second surface 224 of the optical fingerprint sensor chip 220 is electrically connected to the circuit board 210 through the electrical conductor 260 by a solder reflow process, so that the sensing signal of the photo sensor area 222a can be transmitted to the circuit board 210 through the conductive material 228 in the through hole 226 and the electrical conductor 260. However, in other embodiments, in step S330, the conductive body 260 may be disposed on the surface 212 of the circuit board 210 by a ball-planting process, and then connected to the second surface 224 by a reflow process.
Further, in step S330, in the optical fingerprint sensor chip 220, the photosensitive device region 222a may cover most of the first surface 222, so that the area of the photosensitive device 222a on the first surface 222 is relatively high. The photo-sensing device region 222a may have a plurality of photo-sensing units for receiving light and generating an electrical sensing signal. The plurality of light sensing units may be arranged in an array, and each light sensing unit may include a photodiode. In this embodiment, the optical fingerprint sensor chip 220 may be implemented by a flip-chip through silicon via technology, and the through hole 226 may be formed by an etching process. The conductive material 228 may be a conductive metal layer, and the conductive material 228 may cover the sidewalls and the bottom of the via 226 and be electrically connected to the photo device region 222a at the first surface 222. The conductive material 228 is also connected to the circuit board 210 through the conductive body 260, and the sensing signal of the photosensitive device region 222a can be transmitted to the conductive body 260 at the second surface 224 and further transmitted to the circuit board 210 through the conductive material 228 in the through hole 226. It is understood that the second surface 224 may also have conductive traces formed thereon, and the conductive material 228 in the via 226 may be electrically connected to the conductive body 260 through the conductive traces. The number of the conductive bodies 260 may be plural, and the conductive bodies 260 may be conductive particles such as conductive metal balls, for example, solder balls. Specifically, the conductive body 260 may be disposed on the second surface 224 by a ball-bonding process, and then connected to the surface 212 of the circuit board 210 by a reflow soldering process. The circuit board 210 may be a flexible circuit board, and the surface 212 of the circuit board 210 may have metal wires connected to the conductive bodies 260 to receive the sensing signals transmitted by the conductive bodies 260. The circuit board 210 may be electrically connected to other circuit boards of the electronic device (e.g., a printed circuit board) to transmit the sensing signal to other circuit boards of the electronic device (e.g., a printed circuit board).
Specifically, in step S340, as shown in fig. 5, 8 and 2, a surface of the light guide element 230 and the second filter film 246 of the filter element 240, which are obtained in step S320 and are far from the substrate 242, and at least one of the first surface 222 of the optical fingerprint sensor chip 220, which is obtained in step S330 and is shown in fig. 8, are provided with a surface adhesive layer 250, and then the second filter film 246 and the first surface 222 are covered and adhered by the surface adhesive layer 250, so as to obtain the optical fingerprint module 200. More specifically, the surface adhesive layer 250 may be a Die Attach Film (DAF) and an optical adhesive (OCA), but is not limited thereto.
As shown in fig. 9, more specifically, in one embodiment of the method for manufacturing the optical fingerprint module shown in fig. 3, the method may include the following steps S902-S920 for forming the optical fingerprint module 200 shown in fig. 2.
Step S902, a substrate is provided. Specifically, as shown in fig. 4, a substrate 242 may be provided.
Step S904, performing evaporation or sputtering on the front and back surfaces of the substrate to form a first filter and a second filter. Specifically, as shown in fig. 4, the first and second filters 244 and 246 can be formed on the front and back surfaces of the substrate 242 by evaporation or sputtering.
Step S906, forming an optical microlens material layer on the surface of the first filter film away from the substrate. Specifically, as shown in fig. 5, a layer of optical microlens material may be formed on the surface of the first filter film 244 away from the substrate 242.
Step S908, embossing and photocuring the optical microlens material layer to form a plurality of optical microlenses. Specifically, as shown in fig. 5, the layer of optical microlens material is embossed and photocured to form a plurality of optical microlenses 232.
In step S910, a light-shielding material layer is deposited on the surfaces of the optical microlenses away from the first filter film. Specifically, as shown in fig. 5, a light shielding material layer is deposited on the surface of the plurality of optical microlenses 242 away from the first filter 244.
In step S912, the light-shielding material layer is exposed and developed by a mask, so that a light-shielding layer is formed between adjacent optical microlenses and at least a portion of the plurality of optical microlenses is exposed. Specifically, as shown in fig. 5, the light-shielding material layer is subjected to mask exposure development so that a light-shielding layer 234 is formed between adjacent optical microlenses 232 and at least a portion of the plurality of optical microlenses 232 is exposed.
Step S914, providing an optical fingerprint sensor chip, an electrical conductor and a circuit board, where the optical fingerprint sensor chip includes a first surface having a photosensitive device region, a second surface disposed opposite to the first surface, and a through hole penetrating the first surface and the second surface, and the through hole has a conductive layer therein for transmitting a sensing signal of the photosensitive device region to the second surface. Specifically, as shown in FIG. 6, an optical fingerprint sensor chip 220 and an electrical conductor 260 are provided. The optical fingerprint sensor chip 220 includes a first surface 222 having a photo sensing device region 222a, a second surface 224 disposed opposite to the first surface 222, and a through hole 226 penetrating the first surface 222 and the second surface 224, wherein the through hole 226 has a conductive material 228 for transmitting a sensing signal of the photo sensing device region 222a to the second surface 224.
Step S916, disposing the conductor on the second surface of the optical fingerprint sensor chip by a ball-planting process. Specifically, as shown in fig. 7, the conductive body 260 is disposed on the second surface 224 of the optical fingerprint sensor chip 220 through a ball-planting process.
Step S918, electrically connecting the second surface of the optical fingerprint sensor chip to the circuit board through the conductor by a reflow soldering process. Specifically, as shown in fig. 7 and 8, the second surface 224 of the optical fingerprint sensor chip 220 is electrically connected to the circuit board 210 through the electrical conductor 260 by a reflow soldering process.
Step S920, cover and attach the surface of the filter element away from the light guide element to the first surface through a surface adhesive layer. As shown in fig. 5, 8 and 2, a surface of the light guide element 230 and the second filter film 246 of the filter element 240 as shown in fig. 5 obtained in step S3912, which is away from the substrate 242, and at least one of the first surface 222 of the optical fingerprint sensor chip 220 as shown in fig. 8 obtained in step S918 are provided with a surface adhesive layer 250, and the second filter film 246 and the first surface 222 are covered and adhered by the surface adhesive layer 250, so as to obtain the optical fingerprint module 200.
It can be understood that the material, structure and other features of the components of the method for manufacturing the optical fingerprint module according to the embodiment shown in fig. 9 have been described and explained in detail in the steps of the method for manufacturing the optical fingerprint module according to the embodiment shown in fig. 3, and thus are not repeated herein. In addition, in some other embodiments, steps S902 to S912 may be performed simultaneously with steps S914 to S918, or steps S914 to S918 may be performed before steps S902 to S912.
In the method for manufacturing an optical fingerprint module according to the embodiment of the present invention, the filter element 240 and the light guide element 230 are externally attached to the first surface 222 of the optical fingerprint sensor chip 220 using the through-hole technology through the surface adhesive layer 250, so that the yield loss of the chip due to the integration of the light guide element and the filter element on the optical fingerprint sensor chip can be avoided, and the manufacturing of the filter element 240 and the light guide element 239 (such as steps S902 to S912) and the manufacturing of the optical fingerprint sensor chip 220 and the connection of the optical fingerprint sensor chip 220 and the circuit board 210 (such as steps S914 to S918) can be performed separately or simultaneously, and the filter element 240 and the light guide element 239 are attached to the optical fingerprint sensor chip 220 through the surface adhesive layer 250 after the respective manufacturing or connection is completed, so that the surface adhesive layer attaching process is simpler than the process of directly integrating the filter element on the optical fingerprint sensor chip, the problems of low efficiency and low productivity caused by the sequential manufacturing of direct integration can be improved.
In addition, since the optical fingerprint sensor chip 220 adopts the through hole technology, the optical filter element 240 is conveniently adhered to the first surface 222 of the optical fingerprint sensor chip 220 through the surface adhesive layer 250, and the surface adhesive layer 250 can keep a better fixing strength between the optical filter element 240 and the optical fingerprint sensor chip 220, so that the overall strength of the optical fingerprint module 200 is improved; moreover, the edge region of the first surface 222 of the optical fingerprint sensor chip 220 is not required to be electrically connected to other external circuit devices by using metal bonding wires, but can be electrically connected to other external circuit devices (including but not limited to a flexible circuit board) through the second surface 224, so that the edge region can be removed or reduced and the module light leakage problem can be improved.
In addition, since the sensing signal of the photo sensor region 222a is transmitted to the second surface 224 by the via technology, the edge region of the first surface 222 of the optical fingerprint sensor chip 220 except for the photo sensor region 222a can be removed or reduced, and thus the planar size of the optical fingerprint module 220 obtained by the manufacturing method can be smaller and the planar area ratio of the photo sensor region 222a can be higher.
Further, a first filter film 244 is formed by evaporation or sputtering on the surfaces of the substrate 242 and the substrate 242, and the surface of the first filter film 244 away from the substrate 242 forms the light guiding element 230, so that the light guiding element 230 does not need to be provided with a substrate, the thickness of the whole device is small, and the light guiding element 230 and the light filtering element 240 can be combined tightly, thereby ensuring the reliability of the optical fingerprint module 200.
Further, a second filter film 246 is formed on the surface of the substrate 242 away from the first filter film 244 by evaporation or sputtering, the surface of the second filter film 246 away from the substrate 242 is used for covering and attaching the first surface 222 of the optical fingerprint sensor chip 220 through a surface adhesive layer 250, and the first and second filter films 244 and 246 can achieve a better light filtering effect, so that the phenomenon that interference light enters the photosensitive device region 222a to affect fingerprint identification is reduced.
Further, a plurality of optical micro lenses 232 are formed by impressing and photocuring the optical micro lens material layer and a light shield layer 234 is formed by exposing and developing the light shield material layer, and then the plurality of optical micro lenses 232 and the light shield layer 232 do not need to be provided with a base material, so that the thickness of the whole device is small, the first filter film 244 can be tightly combined with the plurality of optical micro lenses 232 and the light shield layer 234, and the reliability of the optical fingerprint module 200 is further ensured.
Further, before the step of covering and adhering the surface of the filter element 240 away from the light guide element 230 to the first surface 222 through the surface adhesive layer 250, the second surface 224 of the optical fingerprint sensor chip 220 is electrically connected to the circuit board 210 through the conductor 260 by using ball-planting and reflow soldering processes, which not only can ensure the reliability of the electrical connection, but also can transmit the sensing signals transmitted by the conductive material 228 of the through hole 226 and the second surface 224 to the circuit board 210 through the conductor 260, thereby avoiding the use of metal bonding wires, further removing or reducing the edge area and improving the module light leakage problem. In addition, the second surface 224 of the optical fingerprint sensor chip 220 is electrically connected to the circuit board 210, and then is covered and attached to the optical filter element 240 through the surface adhesive layer 250, so that the optical filter element 240 and the optical guiding element 230 are prevented from being damaged by ball-mounting and reflow soldering processes, and the optical filter element 240 and the optical guiding element 230 are also prevented from being affected by the ball-mounting and reflow soldering processes.
The technical features of the embodiments described above may be arbitrarily combined, and for the sake of brevity, all possible combinations of the technical features in the embodiments described above are not described, but should be considered as being within the scope of the present specification as long as there is no contradiction between the combinations of the technical features. The above-mentioned embodiments only express several embodiments of the present invention, and the description thereof is more specific and detailed, but not construed as limiting the scope of the invention. It should be noted that, for a person skilled in the art, several variations and modifications can be made without departing from the inventive concept, which falls within the scope of the present invention. Therefore, the protection scope of the present patent shall be subject to the appended claims.
Claims (10)
1. The utility model provides an optical fingerprint module, its characterized in that, optical fingerprint module includes:
the optical fingerprint sensor chip comprises a first surface with a photosensitive device area, a second surface arranged opposite to the first surface, and a through hole penetrating through the first surface and the second surface, wherein the through hole is provided with a conductive material for transmitting a sensing signal of the photosensitive device area to the second surface;
a light directing element disposed on a side of the optical fingerprint sensor chip where the first surface is located; and
the light guide element is formed on the light filtering element, the light filtering element is located between the first surface and the light guide element, the light filtering element is covered and attached to the first surface through a surface adhesive layer, and the light filtering element is used for filtering interference light of the guide light of the light guide element and then providing the interference light to the photosensitive device area.
2. The optical fingerprint module of claim 1, wherein the filter element comprises a substrate and a filter film disposed on at least one side of the substrate; the light guide element comprises a plurality of optical micro lenses and a light shielding layer positioned between every two adjacent optical micro lenses, and the optical micro lenses are formed on the surface, far away from the optical fingerprint sensor chip, of the light filtering element through an embossing process.
3. The optical fingerprint module of claim 2, wherein the filter element comprises a first filter located between the substrate and the plurality of optical microlenses and a second filter located on a side of the substrate adjacent to the first surface, the surface of the first filter away from the substrate forms the plurality of optical microlenses, and the surface of the second filter away from the substrate is covered and attached to the first surface through the surface adhesive layer.
4. The optical fingerprint module of claim 1, further comprising a circuit board located at a side of the second surface of the optical fingerprint sensor chip, and an electrical conductor located between the circuit board and the second surface, wherein the electrical conductor is configured to transmit the sensing signal transmitted by the conductive material of the through hole to the circuit board.
5. The utility model provides an optical fingerprint module manufacturing approach, its characterized in that, optical fingerprint module manufacturing approach includes following step:
providing a filter element;
forming a light guide element on the surface of the filter element, wherein the filter element is used for filtering interference light of the guide light of the light guide element;
providing an optical fingerprint sensor chip, wherein the optical fingerprint sensor chip comprises a first surface with a photosensitive device area, a second surface arranged opposite to the first surface, and a through hole penetrating through the first surface and the second surface, and the through hole is provided with a conductive material used for transmitting a sensing signal of the photosensitive device area to the second surface; and
the surface of the light filtering element far away from the light guide element is covered and attached to the first surface through a surface adhesive layer.
6. The method of claim 5, wherein the step of providing the filter element comprises:
providing a substrate; and
and carrying out evaporation or sputtering on the surface of the substrate to form a first filter film, wherein the surface of the first filter film, which is far away from the substrate, forms the light guide element.
7. The method of claim 6, wherein the step of providing the filter element further comprises:
and forming a second filter film on the surface of the substrate far away from the first filter film by evaporation or sputtering, wherein the surface of the second filter film far away from the substrate is in covering fit with the first surface of the optical fingerprint sensor chip through the surface adhesive layer.
8. The method for manufacturing an optical fingerprint module according to claim 6, wherein the step of forming the light guiding element on the surface of the light filtering element comprises:
forming an optical microlens material layer on the surface of the first filter film, which is far away from the substrate;
embossing and photocuring the optical microlens material layer to form a plurality of optical microlenses;
depositing a shading material layer on one side of the optical micro lenses far away from the first filter film; and
and carrying out photomask exposure development on the shading material layer so that a shading layer is formed between the adjacent optical micro lenses and at least part of the plurality of optical micro lenses is exposed to receive light.
9. The method for manufacturing an optical fingerprint module according to claim 5, further comprising the following steps before the step of adhering the surface of the filter element away from the light guide element to the first surface by the adhesive surface layer:
providing a conductor and a circuit board;
arranging the conductor on the second surface of the optical fingerprint sensor chip by a ball planting process; and
the second surface of the optical fingerprint sensor chip is electrically connected with the circuit board through the electric conductor by a reflow soldering process, so that the sensing signal of the photosensitive device area can be transmitted to the circuit board through the electric conductor and the electric conductive material in the through hole.
10. An electronic device, characterized in that the electronic device comprises an optical fingerprint module according to any one of claims 1 to 4.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202010346302.XA CN111639532A (en) | 2020-04-27 | 2020-04-27 | Optical fingerprint module, manufacturing method thereof and electronic equipment |
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202010346302.XA CN111639532A (en) | 2020-04-27 | 2020-04-27 | Optical fingerprint module, manufacturing method thereof and electronic equipment |
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| CN111639532A true CN111639532A (en) | 2020-09-08 |
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| Application Number | Title | Priority Date | Filing Date |
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| CN202010346302.XA Withdrawn CN111639532A (en) | 2020-04-27 | 2020-04-27 | Optical fingerprint module, manufacturing method thereof and electronic equipment |
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| CN (1) | CN111639532A (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN113299836B (en) * | 2020-11-10 | 2023-11-17 | 友达光电股份有限公司 | photosensitive device |
-
2020
- 2020-04-27 CN CN202010346302.XA patent/CN111639532A/en not_active Withdrawn
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN113299836B (en) * | 2020-11-10 | 2023-11-17 | 友达光电股份有限公司 | photosensitive device |
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Address after: 330096 No.699 Tianxiang North Avenue, Nanchang hi tech Industrial Development Zone, Nanchang City, Jiangxi Province Applicant after: Jiangxi OMS Microelectronics Co.,Ltd. Address before: 330096 Jiangxi Nanchang Nanchang hi tech Industrial Development Zone, east of six road, south of Tianxiang Avenue. Applicant before: OFilm Microelectronics Technology Co.,Ltd. |
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