CN211293954U

CN211293954U - Fingerprint sensor assembly and intelligent terminal

Info

Publication number: CN211293954U
Application number: CN201921379338.7U
Authority: CN
Inventors: 文声敏; H.陈; C.肖; J.古德尔
Original assignee: Synaptic
Current assignee: Synaptic
Priority date: 2019-08-23
Filing date: 2019-08-23
Publication date: 2020-08-18
Anticipated expiration: 2029-08-23

Abstract

The utility model relates to a fingerprint sensor subassembly (100), include: a sensing element (110) having a first surface (101) and a second surface (102) opposite the first surface (101), the first surface (101) having one or more wire bond pads (130) disposed thereon; an integrated circuit die (120) coupled with the second surface (102) of the sensing element (110). The integrated circuit die (120) includes: a receiving unit for receiving sensor data from the sensing element (110); a processing unit for digitally processing the sensor data received from the sensing element (110) to generate digitally processed sensor data; and an output unit for providing the digitally processed sensor data to the lead pads (130).

Description

Fingerprint sensor assembly and intelligent terminal

Technical Field

The utility model relates to a control technical field, more specifically relates to a fingerprint sensor subassembly.

Background

The fingerprint sensor assembly may provide fingerprint data for verifying the identity of a user. The fingerprint sensor assembly may include metal balls or bumps to enable attachment to a substrate such as a printed circuit board. The metal balls or bumps may also allow signals to be transmitted from the fingerprint sensor to the printed circuit board. However, the metal balls or bumps also contribute to defects, imperfections, and/or distortions of the fingerprint sensor assembly (e.g., when the fingerprint sensor assembly is coupled to a printed circuit board).

SUMMERY OF THE UTILITY MODEL

According to an aspect of the utility model, a fingerprint sensor subassembly is provided, it includes: a sensing element having a first surface and a second surface opposite the first surface, the first surface having one or more wire bond pads disposed thereon; an integrated circuit die coupled with the second surface of the sense element, comprising: a receiving unit for receiving sensor data from the sensing element; a processing unit for digitally processing the sensor data received from the sensing element to generate digitally processed sensor data; and an output unit for providing the digitally processed sensor data to the lead pad.

According to another aspect of the utility model, a fingerprint sensor subassembly is provided, include: a sensing element having a first surface and a second surface opposite to the first surface, the first surface having one or more first lead pads thereon; an integrated circuit die coupled with the second surface of the sensing element; and a printed circuit board coupled with one or more first lead pads on a first surface of the sensing element; wherein the integrated circuit die comprises: a receiving unit for receiving sensor data from the sensing element; a processing unit for digitally processing the sensor data received from the sensing element to generate digitally processed sensor data; and an output unit for providing the digitally processed sensor data to the first lead pad.

Drawings

The exemplary embodiments are shown by way of example only and are not intended to be limited by the figures of the accompanying drawings. The same or similar elements are denoted by the same reference numerals.

Figure 1 shows a schematic view of a fingerprint sensor assembly according to an embodiment of the present invention;

figure 2 shows a schematic view of a fingerprint sensor assembly according to an embodiment of the present invention; and

fig. 3 shows a schematic view of a fingerprint sensor assembly according to an embodiment of the present invention.

Detailed Description

In the following description, numerous specific details are set forth, such as examples of specific components, circuits, and processes, in order to provide a thorough understanding of the present disclosure.

The term "coupled" as used herein means directly coupled to or coupled through one or more intermediate components or circuits. Furthermore, in the following description and for purposes of explanation, specific nomenclature is set forth to provide a thorough understanding of example embodiments. However, it will be apparent to one skilled in the art that these specific details may not be required in order to practice the example embodiments. In other instances, well-known circuits and devices are shown in block diagram form in order to avoid obscuring the present disclosure. Any signals provided over the various buses described herein may be time multiplexed with other signals and provided over one or more common buses. Additionally, the interconnection between circuit elements or software blocks may appear as a bus or a single signal line. Alternatively, each bus may be a single signal line, and each single signal line may alternatively be a bus, and a single line or bus may represent any one or more of a myriad of physical or logical mechanisms for communication between components. The example embodiments should not be construed as limited to the particular examples described herein but are to include within their scope all embodiments defined by the appended claims.

It will be understood that in the context of the present invention, when an element such as a layer, region or substrate is referred to as being formed on, deposited on, or disposed "on" or "over" another element, it can be directly on the other element or intervening elements may also be present. In contrast, when an element is referred to as being "directly on" or "directly over" another element, there are no intervening elements present.

FIG. 1 illustrates an example of a fingerprint sensor assembly 100 in which example embodiments may be implemented. The fingerprint sensor assembly 100 may include a sensor element 110 and an integrated circuit die 120. The sensor element 110 may include a wire bond pad 130 and one or more sensors 140. As shown in fig. 1, the wire bond pads 130 and the sensor 140 may be disposed on a first surface 101 of the sensing element 110, where the first surface 101 is opposite to a second surface 102. Although the first surface 101 and the second surface 102 indicate specific surfaces on the sensing element 110, the items associated with the first surface 101 may be interchanged with the elements associated with the second surface 102.

The sensing element 110 may be formed of silicon, fiberglass, or any other feasible material. In some aspects, the sensor 140 may provide sensor data associated with a user's finger that is near the sensing element 110 or in contact with the sensing element 110. The sensor data may include fingerprint data for detecting or identifying one or more characteristics of a user's fingerprint. In some embodiments, the sensor 140 may include an optical or capacitive sensor to capture and generate sensor data. Although optical and capacitive sensors are described herein, the sensors 140 may include any feasible sensors or sensors to generate sensor data and are not limited thereto.

For simplicity, the sensing element 110 is illustratively depicted as having two lead pads 130. In other embodiments, the sensing element 110 may include any feasible number of wire bond pads 130. As described in more detail below, the wire bond pads 130 can provide electrical connections for signals originating from or terminating at the sensing element 110 and/or the integrated circuit die 120.

The integrated circuit die 120 may be coupled to the sensing elements 110 at the second surface 102. The sensing elements 110 and the integrated circuit die 120 may include electrical connections that may be aligned and coupled to each other to enable the transmission and reception of electrical signals between the sensing elements 110 and the integrated circuit die 120. The electrical connections may be Through Silicon Vias (TSVs), conductive balls, or any other feasible electrical connection. The sensing element 110 and the integrated circuit die 120 can include any number of electrical connections. Electrical connections may be disposed near or on the second surface 102 of the sense elements 110 and near or on the first surface 121 of the integrated circuit die 120 (opposite the first surface 121 of the integrated circuit die 120 is the second surface 122). In some implementations, the sensing elements 110 can be coupled to the integrated circuit die 120 using a flip chip mounting process, which can align the associated electrical connections. For example, solder balls may be placed on some or all of the electrical connections. In other embodiments, copper (Cu) pillars with solder caps may be used for some or all of the electrical connections. The surfaces of the sensing element 110 and the integrated circuit die 120 may be aligned. The electrical connections may be placed in contact with each other. Next, the solder at the solder balls may be reflowed to attach the sensing element 110 to the integrated circuit die 120. In some cases, an underfill material may be used between the sense element 110 and the integrated circuit die 120 (after soldering) to enhance this attachment.

Although not shown in fig. 1, the integrated circuit die 120 may include circuits, components, and/or devices for processing sensor data. In one embodiment, the integrated circuit die 120 may include a receiving unit, a processing unit, and an output unit. Wherein the receiving unit is configured to receive sensor data from the sensing element 110; the processing unit is configured to perform digital processing on the sensor data received from the sensing element 110 to generate digitally processed sensor data; and an output unit for providing the sensor data digitally processed to the lead pads 130. In one embodiment, the processing unit may include one or more analog-to-digital converters (ADCs) to digitize sensor data provided by the sensing elements 110. Sensor data may be transferred from the sensor 140 to circuitry included in the integrated circuit die 120 through electrical connections. The electrical connections may also cause digitized sensor data from the integrated circuit die 120 to be routed to the sensing elements 110. For example, digitized sensor data from one or more circuits in the integrated circuit die 120 can be provided to the lead pads 130 on the first surface 101 of the sensing element 110 through electrical connections.

Fig. 2 illustrates another example of a fingerprint sensor assembly 200 according to some embodiments. The fingerprint sensor assembly 200 may include a sensing element 210, an integrated circuit die 220, and a printed circuit board 230. The sensing elements 210 may be coupled to an integrated circuit die 220, which together may be an implementation of the fingerprint sensor assembly 100.

As shown in fig. 2, the sensing element 210 has a first surface 211 and a second surface 212 opposite to the first surface 211. The first surface 211 of the sensing element 210 can include wire bond pads 213 that couple external signals to the sensing element 210 or couple signals from the sensing element 210 and/or the integrated circuit die 220 to external elements. The wire bond pads 213 may be a conductive material such as copper, aluminum, metal bumps, metal balls, or any other feasible material. Wire bond pads 213 may also be referred to as bond finger pads, bond pads, wire finger pads, bumps, balls, and the like. Although the first surface 211 and the second surface 212 indicate particular surfaces on the sensing element 210, in some embodiments, items associated with the first surface 211 may be interchanged with elements associated with the second surface 212.

The sensing element 210 may be formed of silicon, fiberglass, or any other feasible material. For simplicity, the exemplary sense element 210 is shown with two wire bond pads 213. In other embodiments, the sensing element 210 may include any feasible number of wire bond pads 213. As described in more detail below, wire bond pads 213 may provide electrical connections for signals originating from or terminating at sensing element 210 and/or integrated circuit die 220.

The integrated circuit die 220 may be coupled to the sensing elements 210 at the second surface 212. The sensing element 210 and the integrated circuit die 220 may include electrical connections that may be aligned and coupled to each other to enable the transmission and reception of electrical signals between the sensing element 210 and the integrated circuit die 220. The electrical connections may be Through Silicon Vias (TSVs), conductive balls, or any other feasible electrical connection. The sensing element 210 and the integrated circuit die 220 may include any number of electrical connections. The electrical connection may be disposed near or on the second surface 212 of the sensing element 210. In some embodiments, the sensing elements 210 may be coupled to the integrated circuit die 220 using a flip chip mounting process, which may align the associated electrical connections. For example, solder balls may be placed on some or all of the electrical connections. In other embodiments, copper (Cu) pillars with solder caps may be used for some or all of the electrical connections. The surfaces of the sensing element 210 and the integrated circuit die 220 may be aligned. The electrical connections may be placed in contact with each other. Next, the solder at the solder balls may be reflowed to attach the sensing element 210 to the integrated circuit die 220. In some cases, an underfill material may be used between the sensing element 210 and the integrated circuit die 220 (after soldering) to enhance this attachment.

In fig. 2, the sensing element 210 and the integrated circuit die 220 are disposed over a printed circuit board 230 with an insulating support layer 240 (which may be formed, for example, of an adhesive) disposed therebetween. As shown in fig. 2, a support layer 240 is disposed between the integrated circuit die 220 and the printed circuit board 230 and at least partially surrounds the integrated circuit die 220. More specifically, the adhesive may be an epoxy, an underfill, a molding compound, or any other feasible adhesive material. The adhesive may partially or completely fill the gap between the sensing element 210 and the printed circuit board 230. Warpage of the sensing elements 210 and/or the integrated circuit die 220 can be avoided or mitigated by the provision of the support layer 240.

The printed circuit board 230 may be formed of fiberglass, ceramic, organic, or any other feasible material. The printed circuit board 230 may be a sub-component of a larger device, such as a smart terminal (e.g., a smart phone, a tablet, a laptop, etc.). The printed circuit board 230 may include lead pads 231. The wire bond pad 231 may be similar in composition and function to the wire bond pad 213. For simplicity, the printed circuit board 230 is shown with only two lead pads 231, but the printed circuit board 230 may include any feasible number of lead pads. Wires 232 may bond wire pads 213 to wire pads 231 so that signals from sensing element 210 and/or integrated circuit die 220 may be communicated to printed circuit board 230 via wires 232.

Similar to the embodiment shown in fig. 1, although not shown in fig. 2, the integrated circuit die 220 may include a receiving unit, a processing unit, and an output unit. Wherein the receiving unit is configured to receive sensor data from the sensing element 210; the processing unit is configured to perform digital processing on the sensor data received from the sensing element 210 to generate digitally processed sensor data; and an output unit for supplying the sensor data subjected to the digital processing to the lead pads 213.

In the fingerprint sensor assembly 200, no solder balls or metal bumps are used to couple or attach the sensing element 210 and the integrated circuit die 220 to the printed circuit board 230. Such an arrangement may avoid some or all deformation of the sensing element 210 and/or the integrated circuit die 220 during mounting or solder reflow processes. The elimination of solder balls or metal bumps may further allow the fingerprint sensor assembly 200 to have a smaller size.

Figure 3 shows the fingerprint sensor assembly of figure 2. Some of these elements are illustrated in fig. 2 and will not be described again here. In contrast to fig. 2, the fingerprint sensor assembly 300 in fig. 3 further comprises an encapsulation layer 301. The encapsulation layer 301 is disposed over the printed circuit board 230 and encompasses the sensing elements 210 and the integrated circuit die 220. In one embodiment of the present disclosure, the encapsulation layer 301 may be, for example, a cover glass.

In the foregoing specification, the exemplary embodiments of the invention have been described with reference to specific exemplary embodiments thereof. It will, however, be appreciated that various modifications and changes may be made thereto without departing from the spirit and scope of the disclosure as set forth in the appended claims. The specification and drawings are, accordingly, to be regarded in an illustrative sense rather than a restrictive sense.

Claims

1. A fingerprint sensor assembly, comprising:

a sensing element having a first surface and a second surface opposite the first surface, the first surface having one or more wire bond pads disposed thereon; and

an integrated circuit die coupled with the second surface of the sense element, comprising:

a receiving unit for receiving sensor data from the sensing element;

a processing unit for digitally processing the sensor data received from the sensing element to generate digitally processed sensor data; and

an output unit for providing the digitally processed sensor data to the lead pads.

2. The fingerprint sensor assembly of claim 1, wherein the integrated circuit die is coupled to the second surface of the sensing element by a flip-chip mounting process.

3. The fingerprint sensor assembly of claim 1, wherein the first surface of the sensing element further comprises one or more sensors configured to generate the sensor data.

4. The fingerprint sensor assembly of claim 3, wherein the sensor data comprises fingerprint data.

5. The fingerprint sensor assembly of claim 1, further comprising one or more electrical connections for coupling the sensing element with the integrated circuit die.

6. The fingerprint sensor assembly of claim 1 or 2, wherein the processing unit comprises at least one analog-to-digital converter configured to digitally process the sensor data.

7. A fingerprint sensor assembly, comprising:

the sensing element is provided with a first surface and a second surface opposite to the first surface, and a first group of lead bonding pads are arranged on the first surface;

an integrated circuit die coupled with the second surface of the sensing element; and

a printed circuit board coupled with a first set of lead pads on a first surface of the sensing element;

wherein the integrated circuit die comprises:

a receiving unit for receiving sensor data from the sensing element;

an output unit for providing the digitally processed sensor data to the first set of lead pads.

8. The fingerprint sensor assembly of claim 7, further comprising a support layer disposed between the integrated circuit die and the printed circuit board and at least partially surrounding the integrated circuit die.

9. The fingerprint sensor assembly of claim 8, wherein the support layer is formed from an insulating adhesive.

10. The fingerprint sensor assembly of claim 7, wherein the printed circuit board includes a second set of lead pads.

11. The fingerprint sensor assembly of claim 10, wherein the first set of lead pads and the second set of lead pads are connected by wires.

12. The fingerprint sensor assembly of claim 7, further comprising an encapsulation layer disposed over the printed circuit board, the encapsulation layer encompassing the sensing element and the integrated circuit die.

13. The fingerprint sensor assembly of claim 12, wherein the encapsulation layer is a cover glass.

14. A smart terminal, characterized in that it comprises a fingerprint sensor assembly according to any one of claims 1 to 13.