Ultrasonic sensor, ultrasonic fingerprint module and electronic equipment

Abstract

The utility model discloses an ultrasonic sensor, an ultrasonic fingerprint module and an electronic device, the ultrasonic sensor comprises a substrate, the substrate comprises an effective identification area and a non-effective identification area, the non-effective identification area on the upper surface of the substrate is internally provided with a bonding pad part, and the effective identification area and the bonding pad part are arranged at a preset distance along the length direction of the substrate. The bonding pad part comprises a plurality of bonding pads which are arranged at intervals along the width direction of the ultrasonic sensor, and the area of each bonding pad is 8000-50000 [mu] m < 2 >. According to the utility model, the area of the bonding pad is designed to be 8000mu m < 2 >-50000mu m < 2 >, and on the premise that the size of the ultrasonic sensor is reduced, the reliability and the stability of electric connection with other components are ensured, and the ACF lamination impedance is reduced.

Description

[0001] CLAIM OF PRIORITY AND CROSS-REFERENCE TO RELATED APPLICATIONS

[0002] This patent document claims priority to and the benefit of the filing date of an International Patent Application with the application number PCT / CN2024 / 075299, filed on February 1, 2024, and entitled “Ultrasonic Sensor, Ultrasonic Fingerprint Module, Manufacturing Method Thereof, and Electronic Device” by the applicant HUIKE (SINGAPORE) HOLDINGS PTE. LTD. TECHNICAL FIELD

[0003] The utility model relates to the field of fingerprint identification technology, more specifically, the utility model is an ultrasonic sensor, an ultrasonic fingerprint module, and an electronic device. BACKGROUND

[0004] There are various schemes for fingerprint identification technology, including capacitive fingerprint, optical fingerprint, and ultrasonic fingerprint. Currently, ultrasonic fingerprint technology is most widely used. With the increasing thinness of electronic devices, the application of full-screen and narrow frame leaves less and less space for optical sensors. However, the current optical sensors are relatively large in size, resulting in a large window opening in the screen of the electronic device, a large occupation of the overall structure space of the electronic device, and high cost. SUMMARY

[0005] To this end, the utility model embodiments provide the following technical solutions:

[0006] The utility model embodiment provides an ultrasonic sensor, which comprises a substrate, the substrate comprises an effective identification area and a non-effective identification area, a pad portion is arranged in the non-effective identification area on the upper surface of the substrate, the effective identification area and the pad portion are arranged at a predetermined distance along the length direction of the substrate, the pad portion comprises a plurality of pads arranged at intervals along the width direction of the ultrasonic sensor, the area of the pad is 8000um 2 -50000um 2 .

[0007] Further, the first straight line distance o from the edge of the effective identification area close to the pad portion to the side of the substrate close to the pad portion is 0.9mm-2.5mm, and the second straight line distance g from the edge of the effective identification area close to the pad portion to the pad portion is 0.8mm-2.4mm.

[0008] Further, the first straight line distance o is 1.5mm, and the second straight line distance g is 1.2mm.

[0009] Further, each pad comprises a plurality of first pads arranged at intervals along the width direction of the ultrasonic sensor.

[0010] Further, the sum of the areas of all the first pads in each of the pads is 8000um 2 - 50000um 2 .

[0011] Further, the ultrasonic sensor further comprises an acoustic layer, the acoustic layer is arranged on the upper surface of the substrate, the acoustic layer comprises a piezoelectric layer, an upper electrode arranged on the upper surface of the piezoelectric layer, and a lower electrode arranged on the lower surface of the piezoelectric layer, the lower electrode is arranged on the upper surface of the substrate, and the area of the substrate where the lower electrode is located is referred to as an effective identification area.

[0012] Further, the substrate of the ultrasonic sensor is a silicon-based substrate or a glass substrate.

[0013] The utility model embodiment further provides an ultrasonic fingerprint module, including the ultrasonic sensor and flexible circuit board that the embodiment is described above, the flexible circuit board is used for with external circuit connection, the pad part of the ultrasonic sensor with the electric connection area of the flexible circuit board is through ACF glue and adopts ACF press fit process to realize electric connection, when press fitting, the third straight line distance k of the parallel and close to the edge of the pad part of the effective identification area of the ultrasonic sensor of the pressure head of ACF press fit machine is in the range of: 0.7mm <= k < 2.5mm.

[0014] Further, the third straight line distance k is 1.2mm.

[0015] Further, when the pad part of the ultrasonic sensor and the electric connection area of the flexible circuit board are press fitted by ACF glue and ACF press fit process, the press fit pressure is 10N-100N, and the press fit temperature of the area where the ACF glue is located is 110 DEG C-160 DEG C.

[0016] Further, when the pad part of the ultrasonic sensor and the electric connection area of the flexible circuit board are press fitted by ACF glue and ACF press fit process, the press fit pressure is 25N, and the press fit temperature of the area where the ACF glue is located is 148 DEG C.

[0017] Further, when the pad part of the ultrasonic sensor and the electric connection area of the flexible circuit board are press fitted by ACF glue and ACF press fit process, in the length direction of the pad part, the pressure head of the ACF press fit machine completely covers or partially covers the pad part.

[0018] Further, when the pad part of the ultrasonic sensor and the electric connection area of the flexible circuit board are press fitted by ACF glue and ACF press fit process, the length n of the projection of the pressure head of the ACF press fit machine on the ultrasonic sensor is 0.2mm-1mm.

[0019] Further, the length n of the projection of the pressure head of the ACF press on the ultrasonic sensor is 0.3mm.

[0020] The utility model embodiment further provides an electronic device comprising the ultrasonic sensor of the above embodiment, or the ultrasonic fingerprint module of the above embodiment.

[0021] Beneficial effects

[0022] The utility model discloses beneficial effect is: the area of pad is designed as 8000um 2 -50000um 2 Under the premise of reducing the size of the ultrasonic sensor, the electrical connection reliability and stability with other components are ensured, and the ACF pressing impedance is reduced, the problems of large optical sensor size, large electronic device screen window, large electronic device whole machine structure space occupation and high cost are solved, the cost is reduced, and the screen is more convenient. BRIEF DESCRIPTION OF DRAWINGS

[0023] In order to more clearly illustrate the technical scheme in the utility model embodiment, the following will briefly introduce the drawing needed to be used in each embodiment description, and obviously, the drawing in the following description is only some embodiments of the utility model embodiment, and for those skilled in the art, other drawings can also be obtained according to the drawings in the following specific description of the utility model embodiment without creating labor.

[0024] Figure 1 It is the top view of ultrasonic sensor.

[0025] Figure 2 It is the side view of ultrasonic sensor.

[0026] Figure 3 It is the structure schematic view of pad part.

[0027] Figure 4 It is the structure schematic view of pad part of another embodiment.

[0028] Figure 5 It is the side view of ultrasonic fingerprint module.

[0029] Figure 6 It is the structure schematic view of ACF pressing process.

[0030] Figure 7 It is the position relation diagram of the head of ACF press and pad part.

[0031] Figure 8 It is the position relation diagram of the head of ACF press and pad part of another embodiment.

[0032] In the figure, 1, ultrasonic sensor; 11, substrate; 111, effective identification area; 12, pad part; 13, pad; 14, first pad; 15, acoustic layer; 151, piezoelectric layer; 152, upper electrode; 153, lower electrode; 2, flexible circuit board; 3, back support; 4, ACF press; 41, press head; 5, FPC platform; 6, ACF glue; 7, buffer plate.

[0033] Embodiments of the present application

[0034] The technical solutions of the ultrasonic sensor, the ultrasonic fingerprint module and the electronic equipment provided by the embodiments of the present application will be described clearly and completely below in conjunction with the drawings in the specification. Obviously, the described embodiments are only part of the embodiments of the present application, rather than all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative labor fall within the scope of protection of the present application.

[0035] In the description of the embodiments of the present application, it should be understood that the orientations or positional relationships indicated by the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer" and the like are based on the orientations or positional relationships shown in the drawings, and are only for the convenience of describing the embodiments of the present application and simplifying the description, and therefore cannot be understood as indicating or implying that the devices or elements indicated must have a particular orientation, be constructed and operated in a particular orientation, and therefore cannot be understood as a limitation on the embodiments of the present application. In addition, the terms "first", "second", "third" and the like are only for the purpose of description, and cannot be understood as indicating or implying relative importance or implicitly indicating the number of the technical features indicated. Therefore, the features limited by "first", "second", "third" can explicitly or implicitly include one or more features. In the description of the embodiments of the present application, the meaning of "multiple" is two or more, unless otherwise specifically limited.

[0036] In the embodiments of the present application, unless otherwise specifically defined and limited, the terms "mounting", "connection", "connection", "fixing" and the like should be understood in a broad sense, for example, it can be fixedly connected, or it can be detachably connected, or it can be integrated; it can be mechanically connected, or it can be electrically connected; it can be directly connected, or it can be indirectly connected through an intermediate medium; it can be the communication or interaction relationship between two elements, unless otherwise specifically limited. For those skilled in the art, the specific meanings of the above terms in the embodiments of the present application can be understood according to the specific circumstances.

[0037] In the embodiments of the present application, the word "exemplary" is used to mean "serving as an example, instance, or illustration." Any embodiment described as "exemplary" in the embodiments of the present application is not necessarily to be construed as preferred or advantageous over other embodiments. The following description is presented to enable any person skilled in the art to make and use the embodiments of the present application. In the following description, for the purposes of explanation, numerous specific details are set forth in order to provide a thorough understanding of the embodiments of the present application. It is apparent, however, to one skilled in the art that the embodiments of the present application can be practiced without using these specific details. In other instances, well-known structures and processes are not elaborated in order not to obscure the description of the embodiments of the present application with unnecessary details. Therefore, the embodiments of the present application are not intended to be limited to the embodiments shown, but are to be accorded the widest scope consistent with the principles and features disclosed herein.

[0038] Referring to Figure 1 and Figure 2 , Figure 1 is a top view of the ultrasonic sensor, Figure 2 is a side view of the ultrasonic sensor. The embodiment specifically discloses an ultrasonic sensor, which comprises a substrate 11 and an acoustic layer 15, the acoustic layer 15 is arranged on the upper surface of the substrate 11, the acoustic layer 15 comprises a piezoelectric layer 151, an upper electrode 152 arranged on the upper surface of the piezoelectric layer 151 and a lower electrode 153 arranged on the lower surface of the piezoelectric layer 151, the lower electrode 153 is an electrode array formed by a plurality of pixel units, the lower electrode 153 is arranged on the upper surface of the substrate 11, the substrate 11 is integrated with a circuit, the area of the substrate 11 where the lower electrode 153 is located is referred to as an active area (AA area) 111, therefore, the substrate 11 comprises the active area 111 and a non-active area (non-AA area), the area of the upper electrode 152 is equal to or greater than that of the lower electrode 153, therefore, the acoustic layer 15 can only cover the active area 111 or completely cover the active area 111 and part of the non-active area. The non-active area on the upper surface of the substrate 11 is provided with a pad part 12, and the active area 111 and the pad part 12 are arranged at a predetermined distance along the length direction of the substrate 11.

[0039] Referring to Figure 3 , the pad part 12 comprises a plurality of pads 13 arranged at intervals in the width direction of the ultrasonic sensor 1, and the pads 13 realize the electrical connection between the ultrasonic sensor 1 and other components. Further, the area of the pad 13 is 8000um 2 -50000um 2The size of the pad 13 directly affects the impedance of the ACF (Anisotropic Conductive Film) after compression. The larger the size of the pad 13, the smaller the impedance of the ACF after compression. Therefore, the area of the pad 13 is designed to be 8000 um 2 -50000 um 2 Under the premise of reducing the size of the ultrasonic sensor 1, the electrical connection reliability and stability with other components are ensured, and the ACF compression impedance is reduced. For example, the length of the pad 13 is 120 um, the width is 80 um, and the area is 9600 um 2 ; or the length of the pad 13 is 300 um, the width is 90 um, and the area is 27000 um 2 ; or the length of the pad 13 is 500 um, the width is 100 um, and the area is 50000 um 2 The area of the pad 13 is flexibly set according to the actual application scenario and electrical connection requirements.

[0040] Optionally, referring to Figure 4 The pad part 12 includes a plurality of pads 13 arranged at intervals in the width direction of the ultrasonic sensor 1. Each pad 13 includes a plurality of first pads 14 arranged at intervals in the width direction of the ultrasonic sensor 1. Each pad 13 is divided into a plurality of first pads 14, and Figure 3 Compared with the structure of the pad part 12 shown in Figure 4 The scheme shown in increases the overall width of the pad 13 on the substrate 11 due to the spacing between the first pads 14, that is, increases the width of the entire pad part 12, further increases the contact area of the pad part 12 with other components, and the connection is more reliable and stable. Further, the total area of all first pads 14 in each pad 13 is 8000 um 2 -50000 um 2 The area of the first pad 14 is flexibly set according to the actual application scenario and electrical connection requirements. Further, each pad 13 includes two or three first pads 14, so that the area of the first pad 14 is not too small, the actual contact area of the first pad 14 with other components is ensured, and the ACF compression impedance is reduced, and the processing and production are facilitated.

[0041] The first straight line distance o from the edge of the effective recognition area 111 close to the pad portion 12 to the fourth side of the substrate 11 close to the pad portion 12 is 0.9mm-2.5mm, and the second straight line distance g from the edge of the effective recognition area 111 close to the pad portion 12 to the pad portion 12 is 0.8mm-2.4mm. The above setting shortens the distance from the pad portion 12 to the effective recognition area 111, and further reduces the size of the ultrasonic sensor 1, that is, when the distances from the effective recognition area 111 to the other three sides of the substrate 11 remain unchanged, the distance from the effective recognition area 111 to the fourth side of the substrate 11 is reduced, and further the size of the substrate 11 is reduced, and the proportion of the effective recognition area 111 in the ultrasonic sensor 1 is improved.

[0042] Further, the first straight line distance o is 1.5mm, and the second straight line distance g is 1.2mm, which not only reduces the size of the ultrasonic sensor 1, but also maintains the safety distance of each component, improves the proportion of the effective recognition area 111 in the ultrasonic sensor 1, and ensures the performance of the ultrasonic sensor 1.

[0043] Optionally, the substrate 11 of the ultrasonic sensor 1 is a silicon substrate or a glass substrate.

[0044] In a more preferred embodiment, the size of the ultrasonic sensor 1 can be reduced to 6mm in length and width, the first straight line distance o is 1.5mm, and the second straight line distance g is 1.2mm. Both the safety distance and the distance from the pad portion 12 to the effective recognition area 111 are shortened, and the proportion of the effective recognition area 111 in the ultrasonic sensor 1 is improved.

[0045] Please refer to Figure 5 The application also provides an ultrasonic fingerprint module, which comprises any one of the ultrasonic sensors 1 provided in the above embodiments and a flexible circuit board (FPC) 2, the pad portion 12 of the ultrasonic sensor 1 is electrically connected with the electrical connection area of the flexible circuit board 2, and the flexible circuit board 2 is used to be electrically connected with an external circuit. In the embodiment, the electrical connection area of the flexible circuit board 2 also comprises a pad. The pad portion 12 of the ultrasonic sensor 1 and the electrical connection area of the flexible circuit board 2 can be electrically connected through conductive glue.

[0046] In the embodiment, the pad portion 12 of the ultrasonic sensor 1 and the electrical connection area of the flexible circuit board 2 are electrically connected through the ACF glue 6 by using the ACF pressing process. The ultrasonic sensor 1 and the flexible circuit board 2 are bound through the ACF glue 6, so that the electrical connection is realized, and meanwhile the ACF glue 6 itself has adhesion, so that the ultrasonic sensor 1 and the flexible circuit board 2 are adhered together. Please refer to Figure 6, the ultrasonic sensor 1 is placed on the back up 3, the flexible circuit board 2 is placed on the FPC platform 5, the electrical connection area of the flexible circuit board 2 is placed above the pad part 12 of the ultrasonic sensor 1, the ACF glue 6 is arranged between the pad part 12 of the ultrasonic sensor 1 and the electrical connection area of the flexible circuit board 2, the pressure head 41 of the ACF press 4 is pressed from above the electrical connection area of the flexible circuit board 2, and high-temperature pressing is performed. When pressing, the third straight line distance k from the pressure head 41 of the ACF press 4 to the edge of the effective recognition area 111 of the ultrasonic sensor 1 parallel to the pad part 12 is in the range of 0.7mm≤k<2.5mm, that is, the minimum distance from the pressure head 41 of the ACF press 4 to the effective recognition area 111 of the ultrasonic sensor 1 is 0.7mm, and the part of the acoustic layer 15 corresponding to the effective recognition area 111 is ensured not to be invalid.

[0047] Preferably, the third straight line distance k is 1.2mm.

[0048] Optionally, when the pad part 12 of the ultrasonic sensor 1 and the electrical connection area of the flexible circuit board 2 are pressed by the ACF glue 6 by using the ACF pressing process, the pressing pressure is 10N-100N, and the pressing temperature of the area where the ACF glue 6 is located is 110℃-160℃. When ACF pressing, because the position of the ACF glue 6 and the acoustic layer 15 are on the same substrate 11, the high temperature during pressing will be conducted to the position of the acoustic layer 15 through two ways of substrate conduction and air conduction, and exceeding a certain range will also cause the acoustic layer 15 to be invalid. The embodiment effectively reduces the pressing temperature, and in the case of reducing the size of the ultrasonic sensor 1, it can also ensure that the acoustic layer 15 will not be invalid, at least the part of the acoustic layer 15 corresponding to the effective recognition area 111 will not be invalid, and the display effect of the image is ensured.

[0049] Preferably, when the pad part 12 of the ultrasonic sensor 1 and the electrical connection area of the flexible circuit board 2 are pressed by the ACF glue 6 by using the ACF pressing process, the pressing pressure is 25N, and the pressing temperature of the area where the ACF glue 6 is located is 148℃. In the case of ensuring that the ultrasonic sensor 1 and the flexible circuit board 2 are electrically connected and firmly bonded, the acoustic layer 15 is prevented from being invalid.

[0050] Optionally, please refer to Figure 7 and Figure 8 When the pad part 12 of the ultrasonic sensor 1 and the electrical connection area of the flexible circuit board 2 are pressed by the ACF glue 6 by using the ACF pressing process, in the length direction of the pad part 12, the pressure head 41 of the ACF press 4 completely covers or partially covers the pad part 12, as long as the ACF glue 6 reaches the preset temperature and pressure, the connection between the pad part 12 of the ultrasonic sensor 1 and the electrical connection area of the flexible circuit board 2 is stable and reliable, and the pressing difficulty is reduced.

[0051] Preferably, when the pad part 12 of the ultrasonic sensor 1 and the electric connection area of the flexible circuit board 2 are pressure-bonded by the ACF adhesive 6 through the ACF pressure-bonding process, the length n of the projection of the pressure head 41 of the ACF pressure-bonding machine 4 on the ultrasonic sensor 1 is 0.2mm-1mm, which ensures the area of the ACF adhesive 6 and further ensures the stable and reliable connection between the pad part 12 of the ultrasonic sensor 1 and the electric connection area of the flexible circuit board 2.

[0052] More preferably, when the pad part 12 of the ultrasonic sensor 1 and the electric connection area of the flexible circuit board 2 are pressure-bonded by the ACF adhesive 6 through the ACF pressure-bonding process, the length n of the projection of the pressure head 41 of the ACF pressure-bonding machine 4 on the ultrasonic sensor 1 is 0.3mm.

[0053] The application also provides a manufacturing method of the ultrasonic fingerprint module as described in the above embodiments, comprising:

[0054] The ultrasonic sensor 1 is placed on the back support 3, the ACF adhesive 6 is arranged between the pad part 12 of the ultrasonic sensor 1 and the electric connection area of the flexible circuit board 2, and the electric connection is realized by pressure-bonding through the ACF pressure-bonding machine 4. For details, please refer to Figure 6 The flexible circuit board 2 is placed on the FPC platform 5, the electric connection area of the flexible circuit board 2 is placed above the pad part 12 of the ultrasonic sensor 1, the ACF adhesive 6 is arranged between the pad part 12 of the ultrasonic sensor 1 and the electric connection area of the flexible circuit board 2, the pressure head 41 of the ACF pressure-bonding machine 4 is pressed from above the electric connection area of the flexible circuit board 2, and high-temperature pressure-bonding is performed. The feature is that the pressure-bonding pressure is 10N-100N, the pressure-bonding temperature of the area where the ACF adhesive 6 is located is 110℃-160℃, and the temperature of the back support 3 is 50℃-130℃, which effectively reduces the pressure-bonding temperature and ensures that the acoustic layer 15 will not fail, at least the part of the acoustic layer 15 corresponding to the effective identification area 111 will not fail, and the display effect of the image is not affected.

[0055] Optionally, a buffer plate 7 can be arranged between the pressure head 41 of the ACF pressure-bonding machine 4 and the flexible circuit board 2. The buffer plate 7 is used to buffer the excessive pressure of the pressure head 41, so that the pressure is transmitted to the flexible circuit board 2 and the ultrasonic sensor 1 gently, and moreover, there is a possibility that the surface of the flexible circuit board 2 is uneven, and the buffering effect of the buffer plate 7 can make the ACF adhesive 6 receive uniform pressure. The buffer plate 7 is made of elastic material, and preferably made of silicone material. During pressure-bonding, the buffer plate 7 is placed between the flexible circuit board 2 and the pressure head 41, and after pressure-bonding is completed, the buffer plate 7 can be removed.

[0056] The temperature at the ACF glue 6 of the embodiment of the present application is the temperature after the pressure head 41 and the back support 3 jointly act after the pressure head 41 is pressed down. The temperature at the ACF glue 6, and the temperature of the pressure head 41 and the temperature of the back support 3 corresponding to the temperature are determined before the ultrasonic fingerprint module is produced, and only the temperature of the back support 3 and the pressure head 41 is controlled during the pressing. Before the pressure head 41 is pressed down, the pressure head 41 and the back support 3 are first heated to the corresponding temperature, and then the pressure head 41 is pressed down to apply pressure. During the pressing, the back support 3 is kept at a constant temperature, the pressure head 41 is kept at a constant temperature or pulse heating, the temperature at the ACF glue 6 is ensured to reach the preset temperature, and the ACF glue 6 is cured after being kept at a constant temperature and pressure for a period of time. Then, the pressure head 41 removes the pressure, the ultrasonic sensor 1 and the flexible circuit board 2 are taken down, and the ACF pressing connection is completed.

[0057] Preferably, the pressing pressure of the ACF pressing machine 4 is 25N, the pressing temperature of the region where the ACF glue 6 is located is 148℃, and the temperature of the back support 3 is 120℃, which ensures that the ultrasonic sensor 1 and the flexible circuit board 2 are electrically connected and firmly bonded, and avoids the failure of the acoustic layer 15. Before the pressure head 41 is pressed down, the back support 3 is first heated to 120℃, and the pressure head 41 is heated to 190℃. Then, the pressure head 41 is pressed down to apply pressure. During the pressing, the back support 3 is kept at a constant temperature of 120℃, and the pressure head 41 is kept at a constant temperature of 190℃ or pulse heating, so that the temperature at the ACF glue 6 reaches 148℃. After being kept at a constant temperature and pressure for a period of time, the ACF glue 6 is cured. Then, the pressure head 41 removes the pressure, the ultrasonic sensor 1 and the flexible circuit board 2 are taken down, and the ACF pressing connection is completed.

[0058] The present application also provides an electronic device comprising any one of the ultrasonic sensors 1 provided in the above embodiments, or any one of the ultrasonic fingerprint modules provided in the above embodiments. The electronic device is an electronic device with a display screen, which can be a notebook computer, a mobile phone, a tablet computer, a desktop computer, a game device, a vehicle-mounted electronic device, a wearable smart device, etc.

[0059] The above only describes preferred embodiments of the present application and is not intended to limit the present application. Any modification, equivalent replacement and simple improvement made on the essential content of the embodiments of the present application shall be included in the protection scope of the present application.

Claims

1. An ultrasonic sensor, comprising a substrate (11), characterized in that The substrate (11) includes an effective recognition area (111) and an ineffective recognition area, a pad portion (12) is provided in the ineffective recognition area on the upper surface of the substrate (11), the effective recognition area (111) and the pad portion (12) are arranged at a predetermined distance along the length direction of the substrate (11), the pad portion (12) includes a plurality of pads (13) arranged at intervals along the width direction of the ultrasonic sensor (1), the area of the pad (13) is 8000 um 2 -50000 um 2 .

2. The ultrasonic sensor of claim 1, wherein, A first linear distance o of an edge of the effective recognition area (111) parallel to and close to a side of the pad portion (12) to a first straight line of the substrate (11) parallel to and close to the side of the pad portion (12) is 0.9mm-2.5mm, and a second linear distance g of an edge of the effective recognition area (111) close to a side of the pad portion (12) to the pad portion (12) is 0.8mm-2.4mm.

3. The ultrasonic sensor of claim 2, wherein, The first linear distance o is 1.5mm, and the second linear distance g is 1.2mm.

4. The ultrasonic sensor of claim 1, wherein, Each of the pads (13) comprises a plurality of first pads (14) arranged at intervals in a width direction of the ultrasonic sensor (1).

5. The ultrasonic sensor of claim 4, wherein, The sum of the areas of all the first pads (14) in each of the pads (13) is 8000 um 2 - 50000 um 2 .

6. The ultrasonic sensor of claim 1, wherein, The ultrasonic sensor further comprises an acoustic layer (15) arranged on an upper surface of the substrate (11), the acoustic layer (15) comprising a piezoelectric layer (151), an upper electrode (152) arranged on an upper surface of the piezoelectric layer (151), and a lower electrode (153) arranged on a lower surface of the piezoelectric layer (151), the lower electrode (153) being arranged on the upper surface of the substrate (11), and a region of the substrate (11) where the lower electrode (153) is arranged being referred to as an effective recognition area (111).

7. The ultrasonic sensor of claim 1, wherein, The substrate (11) of the ultrasonic sensor (1) is a silicon-based substrate or a glass substrate.

8. An ultrasonic fingerprint module comprising the ultrasonic sensor (1) of any one of claims 1-7 and a flexible circuit board (2), characterized in that, The flexible circuit board (2) is used to connect with an external circuit, and the pad portion (12) of the ultrasonic sensor (1) is electrically connected to an electrical connection region of the flexible circuit board (2) by ACF (6) using an ACF pressing process, and when pressing, a third linear distance k of a pressing head (41) of an ACF pressing machine (4) to an edge of the effective recognition area (111) of the ultrasonic sensor (1) parallel to and close to the pad portion (12) is in the range of 0.7mm≤k<2.5mm. 9.The ultrasonic fingerprint module of claim 8, wherein, The third linear distance k is 1.2mm. 10.The ultrasonic fingerprint module of claim 8, wherein, When the pad portion (12) of the ultrasonic sensor (1) is pressed to the electrical connection region of the flexible circuit board (2) by ACF (6) using the ACF pressing process, the pressing pressure is 10N-100N, and the pressing temperature of the region where the ACF (6) is located is 110℃-160℃. 11.The ultrasonic fingerprint module of claim 8, wherein, When the pad portion (12) of the ultrasonic sensor (1) is pressed to the electrical connection region of the flexible circuit board (2) by ACF (6) using the ACF pressing process, the pressing pressure is 25N, and the pressing temperature of the region where the ACF (6) is located is 148℃. 12.The ultrasonic fingerprint module of claim 8, wherein, When the pad portion (12) of the ultrasonic sensor (1) is pressed to the electrical connection region of the flexible circuit board (2) by ACF (6) using the ACF pressing process, in a length direction of the pad portion (12), a pressing head (41) of an ACF pressing machine (4) completely covers or partially covers the pad portion (12).

13. The ultrasonic fingerprint module of claim 8, wherein, When the pad part (12) of the ultrasonic sensor (1) and the electric connection area of the flexible circuit board (2) are pressure-bonded by ACF through ACF glue (6), the length n of the projection of the pressure head (41) of the ACF pressure-bonding machine (4) on the ultrasonic sensor (1) is 0.2-1 mm.

14. The ultrasonic fingerprint module of claim 13, wherein, The length n of the projection of the pressure head (41) of the ACF pressure-bonding machine (4) on the ultrasonic sensor (1) is 0.3 mm.

15. An electronic device, comprising: The ultrasonic sensor (1) of any one of claims 1-7, or the ultrasonic fingerprint module of any one of claims 8-14.

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