TWI612437B - Composite substrate sensor device and method of manufacturing such sensor device - Google Patents

Abstract

A composite substrate sensing device includes at least: a first substrate sensing wafer having an upper surface, a lower surface, a side surface, and a scanning and receiving circuit element; a second substrate connected to the first substrate sensing wafer; an insulating layer group including multiple An insulating layer is located on the upper surface of the second substrate and the first substrate sensing wafer on a virtual coplanar surface; the scanning and receiving electrode elements are located on the upper surface of the insulating layer group on the physical coplanar surface. The virtual coplanar surface is substantially Co-planar with the entity; and scanning and receiving wires, partly or wholly formed in the insulating layer group, and electrically connecting these scanning and receiving electrode elements to these scanning and receiving circuit elements, so that the receiving circuit element passes through the receiving electrode element and The receiving wire senses changes in the electric field near the object. The manufacturing method of the above sensing device is also provided.

Description

Composite substrate sensing device and manufacturing method thereof

The present invention generally relates to an electric field array sensing device and a manufacturing method thereof, and more particularly, to a composite substrate sensing device and a manufacturing method thereof.

Traditional non-optical array sensing devices, such as electric field / capacitance, thermal sensing, pressure sensing, etc., are applied to fingerprint sensing devices, for example, because the finger texture must be sensed, the sensing area needs to be maintained with the finger The necessary area of contact to get sufficient sensing accuracy. Taking an electric field / capacitive fingerprint sensor as an example, it has a plurality of sensing elements arranged in an array, and the area occupied by these sensing elements corresponds to the area of a finger on a one-to-one basis. For example, the design of a fingerprint sensor with a resolution of 500dpi, the pitch of the sensing elements in the sensing array is approximately equal to 50 micrometers (um), and each sensing element includes a sensing electrode element and its The corresponding sensing circuit elements below are generally manufactured by integrating the two into a semiconductor integrated circuit (IC) process, such as a complementary metal-oxide-semiconductor (CMOS) process, with the top surface metal ( Top metal) is used as a sensing electrode element to define the pitch of the sensing elements, and at the same time, a corresponding sensing circuit element is formed below each sensing electrode element to form a monolithic design. However, for such a monolithic design, for an area type sensor (area sensor), if it needs to have a large sensing area, it needs to have a large sensing electrode element array and its corresponding sensing circuit element. Arrays, that is to say, traditional electrode elements and circuit elements are one-to-one corresponding areas, and the sensing area is as large as the semiconductor wafer area. For example, if the sensing array has 100 X 100 sensing elements, there will be a sensing electrode element area of about 5mm X 5mm and the sensing circuit element area below 5mm x 5mm. If the surrounding analog and digital circuits are added, The area of the entire fingerprint sensor or chip will be quite large, making the cost quite high.

Therefore, how to reduce the area of the sensing circuit element while still maintaining an equivalently large sensing area is a problem to be solved in this case.

Therefore, an object of the present invention is to provide a sensing device capable of reducing the area of a scanning circuit element, while still maintaining an equivalently large sensing area, and a method for manufacturing the same.

To achieve the above object, the present invention provides a composite substrate sensing device, including at least: a first substrate sensing wafer having an upper surface, a lower surface, a plurality of side surfaces connected to the upper surface and the lower surface, and an underside of the upper surface. A plurality of scanning circuit elements and a plurality of receiving circuit elements; a second substrate connected to one or more of these sides of the first substrate sensing chip; an insulating layer group including a plurality of insulating layers, located at the second An upper surface of one of the substrates and an upper surface of the first substrate sensing wafer, an upper surface of the second substrate and an upper surface of the first substrate sensing wafer are located on a virtual coplanar plane; a plurality of scanning electrode elements and a plurality of receiving electrodes Element, located on the upper surface of one of the insulation layer groups, the upper surface of the insulation layer group is located on a solid coplanar, the virtual coplanar is substantially parallel to the solid coplanar; and a plurality of scanning wires and a plurality of receiving wires are formed in part or all In the insulating layer group, each scanning wire electrically connects one of the columns of the scanning electrode elements to a corresponding one of the scanning circuit elements, and each receiving wire connects the same. One row of the receiving electrode elements is electrically connected to a corresponding one of the receiving circuit elements, and the scanning circuit elements send one or more scanning signals to the scanning electrode elements, so that the receiving circuit elements pass through the receiving electrode elements and These receiving wires sense changes in the electric field near an object.

The invention also provides a method for manufacturing a composite substrate sensing device, which includes at least the following steps: providing a first substrate sensing wafer, the first substrate sensing wafer having an upper surface, a lower surface, and a plurality of connected to the upper surface and the lower surface; A plurality of sides and a plurality of scanning circuit elements and a plurality of receiving circuit elements below the upper surface; providing a second substrate surrounding one or more of the sides connected to the first substrate sensing chip; Forming an insulating layer group including a plurality of insulating layers on the upper surface of one of the second substrates and the upper surface of the first substrate sensing wafer; and a plurality of scanning wires and receiving wires partially or entirely located in the insulating layer group; And forming a plurality of scanning electrode elements and a plurality of receiving electrode elements on an upper surface of one of the insulating layer groups, each scanning wire electrically connecting one row of the scanning electrode elements to a corresponding one of the scanning circuit elements, and each receiving wire One row of the receiving electrode elements is electrically connected to a corresponding one of the receiving circuit elements, and the scanning circuit elements emit one or more scans. At this point the scan signal like electrode elements, these scan electrode through a scanning element such circuit elements a plurality of wires electrically connected to this, so that these reception The circuit element senses an electric field change near the object through the receiving electrode elements and the receiving wires.

With the device and method of the present invention, a composite substrate sensing device suitable for sensing a fingerprint of a finger can be manufactured by using a small-area sensing chip. Therefore, the manufacturing cost of the fingerprint sensing device can be reduced. In addition, by using a lateral electric field to sense fingerprints, the total number of receiving circuit elements and scanning circuit elements is far less than the total number of receiving electrode elements and scanning electrode elements, so the volume of the first substrate sensing wafer can be effectively reduced, thereby reducing costs.

In order to make the above content of the present invention more comprehensible, the following describes the preferred embodiments in detail with the accompanying drawings, as follows.

F‧‧‧finger

PCP‧‧‧ entity coplanar

VCP‧‧‧Virtual Coplanar

10‧‧‧First substrate sensing chip

10A‧‧‧Chip protection layer

11‧‧‧ top surface

12‧‧‧ lower surface

13‧‧‧ side

15‧‧‧scan circuit element

20‧‧‧Second substrate / moulding layer

20C‧‧‧Groove

21‧‧‧ Top surface

30‧‧‧scan electrode

32‧‧‧sensing unit

35‧‧‧Second scanning electrode element

40‧‧‧Scan Lead

45‧‧‧Second scanning wire

50‧‧‧Second substrate sensing chip

51‧‧‧ Top surface

52‧‧‧ lower surface

53‧‧‧ side

55‧‧‧Second scanning circuit element

60‧‧‧Device protection layer

70‧‧‧Insulation layer group

71, 72, 73‧‧‧ Insulation

75‧‧‧ top surface

80‧‧‧ separated conductive layer

90‧‧‧ electric field emission element

92‧‧‧Signal Source

95‧‧‧ Covering board

100‧‧‧ composite substrate sensing device

130‧‧‧Receiving electrode element

140‧‧‧Receiving wire

150‧‧‧Receiving circuit element

150A‧‧‧Transmission electrode

150B‧‧‧Receiving circuit element entity part

350‧‧‧Second receiving electrode element

450‧‧‧Second receiving wire

550‧‧‧Second receiving circuit element

FIG. 1 is a schematic cross-sectional view of a composite substrate sensing device according to a first embodiment of the present invention.

FIG. 2 shows a connection diagram according to the first embodiment of the present invention.

FIG. 3 is a schematic top view of a first embodiment of the present invention.

FIG. 4 shows a schematic diagram of a receiving circuit element according to the first embodiment of the present invention.

FIG. 5 is a schematic front view of a second embodiment of the present invention.

FIG. 6 is a schematic top view of a third embodiment of the present invention.

7A and 7B are schematic front views of two examples according to a fourth embodiment of the present invention.

8 to 9 are schematic cross-sectional views showing steps of the manufacturing method of the first embodiment.

FIG. 10 is a schematic cross-sectional view showing another example of the manufacturing method of the first embodiment.

11A to 11G are schematic diagrams showing various configurations of a first substrate sensing wafer and a second substrate.

FIG. 12 is a schematic diagram showing a size of a sensing unit according to the present invention.

In the embodiment of the present invention, an embedded sensing chip (which can be regarded as a first substrate) is used in a second substrate or the sensing chip is connected to one side of the second substrate. In this embodiment, the second substrate may be A molding compound that is combined into a composite (the composite can be called a composite base Board) to form the wiring and electrodes of the assembly to form a composite substrate-type electric field array sensing device, which can be applied, for example, to a fingerprint sensing device and any sensing electric field change (especially a lateral electric field change) near an object installation. In the present invention, the second substrate may be not limited to a molding compound, and may be any semiconductor silicon substrate and an insulating property such as a glass substrate. In this way, the sensing chip and the scanning electrode element are formed in different processes. Without changing the size of the scan electrode element array, the sensing chip can be effectively reduced, thereby reducing the production cost. Furthermore, multiple sensing chips can be integrated together by using the technology of the embodiments of the present invention to meet various requirements.

FIG. 1 is a schematic cross-sectional view of a composite substrate sensing device 100 according to a first embodiment of the present invention. FIG. 2 shows a connection diagram according to the first embodiment of the present invention. FIG. 3 is a schematic top view of a first embodiment of the present invention. It is worth noting that FIG. 1 is only a schematic diagram showing the connection relationship of the structure, but does not completely correspond to FIG. 2 and FIG. 3. In addition, FIG. 3 does not draw the scanning wires and the receiving wires.

As shown in FIG. 1 to FIG. 3, the composite substrate sensing device 100 of this embodiment includes at least a first substrate sensing wafer 10, a second substrate (molding layer) 20, an insulating layer group 70, and a plurality of scans. The electrode unit 30, the plurality of receiving electrode units 130, the plurality of scanning leads 40, and the plurality of receiving leads 140.

The first substrate sensing wafer 10 has an upper surface 11, a lower surface 12, a plurality of side surfaces 13 connected to the upper surface 11 and the lower surface 12, and a plurality of scanning circuit elements 15 and a plurality of scanning circuits 15 below the upper surface 11. Receive circuit element 150. These scanning circuit elements 15 may be composed of one scanning circuit and a plurality of switching units, or may be independent scanning circuits. These receiving circuit elements 150 may be composed of one receiving circuit and a plurality of switching units, or may be independent receiving circuits.

The first substrate sensing wafer 10 is embedded in the second substrate 20 and becomes a coplanar design with each other. This can completely save the thickness of the device after the completion (exactly the same as the conventional technology using a silicon substrate to complete the sensing). Element array design), which is very important for applications such as mobile phones, where the second substrate 20 is a molding plastic layer 20 surrounding the side surfaces 13 of the first substrate sensing wafer 10. The insulating layer group 70 includes a plurality of insulating layers (for example, insulating layers 71, 72, and 73). The insulating layer group 70 is located on an upper surface 21 of the molding compound layer 20 and the upper surface 11 of the first substrate sensing wafer 10. The upper surface 21 of the plastic layer 20 and the first substrate The upper surface 11 of the sensing chip 10 is located on a virtual coplanar VCP. In another embodiment, the second substrate is connected to one side of the first substrate sensing wafer. For example, the first substrate sensing wafer 10 in FIG. 1 is moved to the left or right to the left or right boundary. The right side or the left side of a substrate sensing wafer may be connected to the molding compound layer 20. That is, one of the side surfaces of the second substrate and the first substrate sensing wafer can be directly contacted.

The plurality of scanning electrode elements 30 and the plurality of receiving electrode elements 130 are located on an upper surface 75 of the insulation layer group 70 and are arranged vertically and horizontally. The upper surface 75 of the insulation layer group 70 is located on a solid coplanar PCP. The virtual coplanar VCP is substantially parallel to the physical coplanar PCP and is separated from the physical coplanar PCP by a distance, which is the vertical distance of the insulation layer group 70. In this embodiment, the scanning electrode cells 30 and the receiving electrode cells 130 are homogeneously distributed above the first substrate sensing wafer 10 and the second substrate 20 to minimize the area of the first substrate sensing wafer 10. Without sacrificing a physical sensing area (area exposed to contact with a finger) of the composite substrate sensing device 100. In another embodiment, the scanning electrode elements 30 and the receiving electrode elements 130 are heterogeneously distributed above the first substrate sensing wafer 10 and the second substrate 20. In yet another embodiment, the scanning electrode elements 30 and the receiving electrode elements 130 are located only above the second substrate 20, but not directly above the first substrate sensing wafer 10.

The plurality of scanning wires 40 and the plurality of receiving wires 140 are partially or completely formed in the insulating layer group 70 (because some of the scanning wires 40 and some receiving wires 140 may be formed above or below the insulating layer group 70), each The scanning wire 40 electrically connects one of the columns of the scanning electrode elements 30 to a corresponding one of the scanning circuit elements 15 (for example, a scanning wire 40 electrically connects the upper scanning circuit element 15 to the upper four scanning lines). Electrode element 30). Each receiving wire 140 electrically connects one row of the receiving electrode elements 130 to a corresponding one of the receiving circuit elements 150 (for example, a receiving wire 140 electrically connects an upper receiving circuit element 150 to the left of three rows of three Receiving electrode element 130). The scanning circuit elements 15 send one or more scanning signals to the scanning electrode elements 30, so that the receiving circuit elements 150 sense a change of an electric field near the object through the receiving electrode elements 130 and the receiving wires 140. In this embodiment, the fingerprint of a finger F is taken as a non-limiting example for explanation, because the interference of the peak or valley of the finger F on the receiving electrode element adjacent to the scanning electrode element can be calculated by the electric field change. , Thereby obtaining the difference information between the peaks or valleys of the finger F. In this embodiment, The scanning electrode elements 30 of one row are electrically connected to each other, and the receiving electrode elements 130 of one row are electrically connected to each other.

In this embodiment, a plurality of scanning circuit elements 15 form a scanning circuit element array, and the numbers of the scanning circuit elements 15 and the scanning electrode elements 30 correspond one-to-many. In other embodiments, one scanning circuit element 15 may correspond to multiple scanning wires 40 and multiple scanning electrode elements 30, so that the number of scanning circuit elements 15 and the area of the first substrate sensing chip can be further reduced; or one scanning circuit The element 15 can correspond to multiple scanning wires and one scanning electrode element, so as to prevent the failed wires from affecting the yield of the product. In addition, a plurality of receiving circuit elements 150 constitute an array of receiving circuit elements. The number of receiving circuit elements 150 and receiving electrode elements 130 corresponds one-to-many. In other embodiments, one receiving circuit element 150 may correspond to multiple receiving wires 140 and multiple receiving electrode elements 130, so that the number of receiving circuit elements 150 and the area of the first substrate sensing chip can be further reduced; or one receiving circuit The element 150 can correspond to multiple receiving wires and one receiving electrode element, so as to prevent the failed wires from affecting the yield of the product. In addition, the plurality of scanning electrode cells 30 and the plurality of receiving electrode cells 130 constitute a scanning receiving electrode cell array. So far, another important feature of the present invention is that it is only necessary to use a one-dimensional linear receiving circuit element 150 to design a two-dimensional sensing array element, which has never been proposed. Of course, the geometrical arrangement of FIG. 2 in this embodiment is only for explaining the features of the present invention, and is not intended to limit the present invention to only be applicable to this line layout arrangement.

In addition, the composite substrate sensing device 100 may further include a device protection layer 60 located on the insulating layer group 70 and the scanning electrode elements 30 and the receiving electrode elements 130. The device protection layer 60 is directly connected to the finger F or Indirect contact can protect the scanning electrode element 30 and the receiving electrode element 130, and the protective layer may be composed of a single material or a composite layer material. Since the first substrate sensing wafer 10 and the molding compound layer 20 are regarded as two substrates, this embodiment is referred to as a composite substrate sensing device 100. The scanning electrode unit 30, the receiving electrode unit 130, the scanning wire 40 and the receiving wire 140 are all located above the first substrate sensing wafer 10 and the molding compound layer 20, that is, the scanning electrode unit 30, the receiving electrode unit 130, and the scanning wire 40. When the receiving wire 140, the scanning circuit element 15 and the receiving circuit element 150 are being projected on the virtual coplanar VCP or the physical coplanar PCP, the coverage of the scanning wire 40 covers the coverage of the scanning circuit element 15, and / or the scanning electrode. The coverage of element 30 covers the coverage of scanning circuit element 15, and / or the coverage of receiving wire 140 covers the coverage of receiving circuit element 150, and / or the coverage of receiving electrode element 130. The coverage area covers the coverage area of the receiving circuit element 150.

FIG. 4 shows a schematic diagram of a receiving circuit element 150 according to the first embodiment of the present invention. As shown in FIG. 4, the receiving circuit element 150 includes a transmitting electrode 150A and a receiving circuit element physical portion 150B electrically connected to the transmitting electrode 150A. The transmitting electrode 150A is electrically connected to the receiving wire 140 and is used as a signal transmission. The transmitting electrode 150A is electrically connected to the receiving wire 140 and is used as a signal transmission. In one example, the receiving circuit element entity part 150B may include a part or all of a front-end sensing circuit, an analog-to-digital conversion circuit, a gain amplifier circuit, an operational amplifier, and other circuits. It is worth noting that when the receiving circuit element 150 is not yet combined with the second substrate (molding material layer) 20, the transmission electrode 150A may be covered with a wafer protection layer 10A, because a plurality of first wafers may be fabricated on the same wafer. A substrate is cut and packaged after the wafer 10 is sensed. Therefore, the wafer protection layer 10A can protect the transmission electrode 150A.

Referring again to FIG. 1, in this embodiment, the insulating layer group 70 is composed of three insulating layers. In other embodiments, the insulating layer group 70 may be composed of four or more insulating layers, depending on the difficulty of the wiring layout. The smaller the ratio of the area of the scanning circuit element 15 in the horizontal direction to the area of the scanning electrode element 30 in the horizontal direction, the larger the number of insulating layers required.

As shown in FIGS. 2 and 3, the scanning circuit elements 15 are arranged in a one-dimensional first array, and the scanning electrode elements 30 and the receiving electrode elements 130 are arranged in a two-dimensional second array. An array and the second array have X and Y axes perpendicular to each other. The size of the first array on the X axis is less than or equal to the size of the second array on the X axis. The first array is on the Y The size on the axis is less than or equal to the size of the second array on the Y axis. That is, the scanning leads 40 and the receiving leads 140 are extended from the scanning circuit element 15 to the scanning electrode element 30 in one or two dimensions.

FIG. 5 is a schematic front view of a second embodiment of the present invention. As shown in FIG. 5, the composite substrate sensing device 100 of this embodiment is similar to the first embodiment, except that it further includes a second substrate sensing wafer 50, a plurality of second scanning electrode elements 35, and a plurality of The second receiving electrode element 350, the plurality of second scanning wires 45, and the plurality of second receiving wires 450.

The second substrate sensing wafer 50 has an upper surface 51, a lower surface 52, a plurality of side surfaces 53 connected to the upper surface 51 and the lower surface 52, and located below the upper surface 11 of the second substrate sensing wafer 50. Multiple second scanning circuit elements 55 and multiple second receiving circuit elements 550, the molding compound layer 20 is connected to one or more of the side surfaces 53 of the second substrate sensing wafer 50 (in this embodiment, these side surfaces 53 surrounding the second substrate sensing wafer 50, and The connection here is, for example, a direct connection). The insulating layer group 70 is located on the upper surface 21 of the molding compound layer 20, the upper surface 11 of the first substrate sensing wafer 10, and the second substrate sensing wafer 50. This upper surface 51. The plurality of second scanning electrode elements 35 and the plurality of second receiving electrode elements 350 are located on the upper surface 75 of the insulating layer group 70 and the upper surface 11 of the second substrate sensing wafer 50. The plurality of second scanning wires 45 and the plurality of second receiving wires 450 are partially or completely formed in the insulating layer group 70, and each of the second scanning wires 45 is electrically connected to one of the columns of the second scanning electrode elements 35 thereto One of the corresponding one of the second scanning circuit elements 55, and each of the second receiving wires 450 electrically connects one row of the second receiving electrode elements 350 to one of the corresponding one of the second receiving circuit elements 550, and the second The scanning circuit element 55 sends one or more second scanning signals to the second scanning electrode elements 35, so that the second receiving circuit elements 550 pass through the second receiving electrode elements 350 and the second receiving wires 450 to cooperate with each other. The receiving circuit element 150 senses the fingerprint of the finger F.

In this embodiment, the second substrate sensing wafer 50 and the first substrate sensing wafer 10 may have the same function and size, and the second substrate sensing wafer 50 and the first substrate sensing wafer 10 are actual electrical properties. Connected (not shown in the figure), such as power supply or synchronized clock, and can also transfer the data of one of them to the other, and then transfer the combined data to the outside by the other. Different designs can be considered as system design and data transmission between independent chips. However, the biggest feature of the present invention is to integrate the largest physical sensing area with the smallest chip area. In this way, the sensing chip can be mass-produced and used as a standard sensing chip. When a designer needs multiple sensing chips to complete a composite substrate sensing device, multiple sensing chips can be used. In other embodiments, the second substrate sensing wafer 50 and the first substrate sensing wafer 10 may have different functions and sizes, and are regarded as two standard components, which are selected by a designer. It is worth noting that in the second substrate sensing wafer 50 and the first substrate sensing wafer 10, not all scanning circuit elements need to be connected to the scanning electrode element, and not all receiving circuit elements need to be connected to the receiving electrode element. To meet the needs of the designer.

FIG. 6 is a schematic top view of a third embodiment of the present invention. As shown in FIG. 6, this embodiment is similar to the first embodiment, except that the conducting wire 40 is extended from the scanning circuit element 15 to the scanning electrode element 30 in one dimension, that is, only along the X-axis direction. expansion. because Therefore, the size of the first array on the X axis is substantially equal to the size of the second array on the X axis, and the size of the first array on the Y axis is smaller than the size of the second array on the Y axis. . This has the advantage that the first substrate sensing wafer 10 can be made into a long strip, and only one-dimensional externally expanded wiring has a simple effect. Combining FIG. 4 and FIG. 6, another feature of the present invention is that the electrode sensing elements are distributed over the first and second substrates according to design, so as to obtain the smallest sensing chip and the smallest sensing device. Geometric area without sacrificing physical sensing area. Of course, the spirit of this embodiment may also include that the scan electrode element is only located above the second substrate.

7A and 7B are schematic front views of two examples according to a fourth embodiment of the present invention. As shown in FIG. 7A, this embodiment is similar to the second embodiment, except that the composite substrate sensing device further includes two separated conductive layers 80 disposed between the receiving electrode element 130 and the receiving circuit element 150, and It is coupled to a fixed potential (for example, it can be 5V, 3.3V or ground potential) for shielding the receiving electrode element 130 and the receiving circuit element 150 from mutual interference. The separate conductive layers 80 are on the same plane. It is worth noting that the separated conductive layer 80 is not electrically connected to the conductive wires 40, 140, 45, and 145, and as long as there is a separated conductive layer 80, the shielding effect can be achieved. As shown in FIG. 7B, this example is similar to FIG. 7A, except that the separated conductive layers 80 are located on two different planes, respectively, and may be partially overlapped or not overlapped when projected on the horizontal plane.

8 to 9 are schematic cross-sectional views showing steps of the manufacturing method of the first embodiment. The manufacturing method of the composite substrate sensing device 100 includes at least the following steps. First, as shown in FIG. 8, a first substrate sensing wafer 10 is provided. The first substrate sensing wafer 10 has an upper surface 11, a lower surface 12, and a plurality of side surfaces 13 connected to the upper surface 11 and the lower surface 12. And a plurality of scanning circuit elements 15 and a plurality of receiving circuit elements 150 located below the upper surface 11. The first substrate sensing wafer 10 is fabricated, for example, from a silicon wafer through a semiconductor process. The first substrate sensing wafer 10 may have the above-mentioned wafer protection layer 10A, of course, in other examples, the wafer protection layer 10A may not be provided.

Then, a molding compound layer 20 is provided, surrounding the side surfaces 13 of the first substrate sensing wafer 10 or connected to one or more of the side surfaces 13. The molding compound layer 20 also covers the first substrate sensing wafer 10 and the wafer protection layer 10A. Details are explained below. First, the first substrate sensing wafer 10 is placed in a mold (not shown), and the molding compound layer 20 is poured to surround the side surfaces 13, the upper surface 11 and the lower surface 12 of the first substrate sensing wafer 10. As shown in Figure 8 Show. Then, regrind is performed to remove the molding compound layer 20 located above the upper surface 11 of the first substrate sensing wafer 10 to expose the scanning circuit element 15 and the receiving circuit element 150, and in particular the transmission of the receiving circuit element 150. The electrode 150A is shown in FIGS. 9 and 4. That is, a regrind step is performed to remove the wafer protection layer 10A located on the first substrate sensing wafer 10 until the transmission electrode 150A of the receiving circuit element 150 is exposed. Of course, the removal operation can also be stopped at the wafer protection layer 10A, and the transmission electrode 150A can be exposed by a general photolithography technique.

It is worth noting that, in another embodiment, a molding compound layer 20 may be provided to be connected to one or more of these side faces 13, and may be connected to the first substrate sensing wafer 10 by injecting the second substrate 20. A side surface 13, an upper surface 11, and a lower surface are then ground back to remove the second substrate 20 located above the upper surface 11 of the first substrate sensing wafer 10.

Next, as shown in FIG. 1, an insulating layer group 70 including a plurality of insulating layers 71, 72, and 73 is formed on the upper surface 11 of the molding compound layer 20 and the upper surface 11 of the first substrate sensing wafer 10. And a plurality of scanning wires 40 and a plurality of receiving wires 140 which are partially or completely located in the insulating layer group 70. The wires 40 and the insulating layers 71, 72, 73 can be completed through processes including, but not limited to, electroplating, etching, and deposition, and particularly a wiring formation process compatible with the semiconductor process. Since those with ordinary knowledge in the art can easily understand how to implement such technology, it will not be repeated here.

Next, as shown in FIG. 1, a plurality of scanning electrode cells 30 and a plurality of receiving electrode cells 130 are formed on the upper surface 75 of the insulating layer group 70, and each scanning wire 40 electrically connects one of the columns of the scanning electrode cells 30 to this. Each receiving wire 140 electrically connects one row of the receiving electrode elements 130 to one of the corresponding receiving circuit elements 150, and the scanning circuit elements 15 issue one or more The scanning signal reaches these scanning electrode cells 30. As such, the receiving circuit elements 150 can sense the fingerprint of the finger F through the receiving electrode elements 130 and the receiving leads 140. Of course, a device protection layer 60 may be formed on the insulating layer group 70, the scan electrode elements 30, and the receiving electrode elements 130, and the device protection layer 60 is in direct or indirect contact with the finger F. The device protection layer 60 is preferably composed of abrasion-resistant materials, and of course, it may include coatings of different colors, or it may be covered with another insulating layer substrate (such as a sapphire substrate) to prevent fingernails or foreign objects. Scratched.

Of course, the manufacturing process described above is explained in order to familiarize the skilled person with the implementation. The spirit of the present invention is not limited to this. For example, FIG. 10 shows the manufacturing method of the first embodiment. A schematic cross-sectional view of another example. The second substrate 20 may also be any semiconductor substrate and insulation characteristics such as a glass substrate, and the manufacturing process may define the same or slightly larger geometric dimensions of the first substrate sensing wafer 10 than the second substrate 20 A recess 20C, and the first substrate sensing wafer 10 is embedded in the second substrate 20, and is integrated through the processes of FIGS. 8 to 9 to make the insulating layer group 70, and the plurality of wires 40. The array of scan electrode cells 30 and the device protection layer 60. It is worth noting that the groove 20C of FIG. 10 does not penetrate the second substrate 20, so after the first substrate sensing wafer 10 is implanted, the bottom portion of the second substrate 20 may be removed by grinding to obtain a substrate as shown in FIG. 9 Shown structure. Of course, it is also possible to directly provide the groove 20C penetrating the second substrate 20 and then implant the first substrate sensing wafer 10 into the second substrate 20 to obtain the structure shown in FIG. 9. Alternatively, the bottom portion of the second substrate 20 need not be removed.

11A to 11G are schematic diagrams showing various configurations of a first substrate sensing wafer and a second substrate. As shown in FIG. 11A, the first substrate sensing wafer 10 is located on the left side of the second substrate 20 and has the same size as the second substrate 20 on the Y axis. As shown in FIG. 11B, the dimensions of the X-axis and the Y-axis of the first substrate sensing wafer 10 are smaller than those of the second substrate 20. As shown in FIG. 11C, the first substrate sensing wafer 10 is located at a corner of the second substrate 20. As shown in FIG. 11D, the first substrate sensing wafer 10 is located at two corners of the second substrate 20. As shown in FIG. 11E, the first substrate sensing wafer 10 is located on the left and right sides of the second substrate 20. As shown in FIG. 11F, the first substrate sensing wafer 10 is located at four corners of the second substrate 20. As shown in FIG. 11G, the first substrate sensing wafer 10 is located at a central portion of the second substrate 20.

FIG. 12 is a schematic diagram showing the size of a sensing unit 32 according to the present invention. As shown in FIG. 12, two adjacent scanning electrode cells 30 and two adjacent receiving electrode cells 130 constitute a sensing unit 32. In the embodiment of the present invention, the sensing unit 32 has a square shape. The size of the sensing unit 32 is between 20 and 100 micrometers, preferably between 40 and 60 micrometers, such as 50 micrometers (corresponding to 500 dpi), so as to meet the resolution requirements of fingerprint sensing. Due to the demand for such a high resolution, it is not easy to complete a complete circuit layout with traditional organic substrate manufacturing and wafer bonding packaging technologies. This is also a feature of the present invention. With the manufacturing technology of a wafer-level composite substrate, the composite substrate can be regarded as a general silicon wafer. The high-resolution scanning and receiving circuit layout is completed on the top, which is also a design that has never been mentioned.

With the above embodiments of the present invention, a small area sensing chip can be used. A composite substrate sensing device suitable for sensing a fingerprint of a finger is made. Therefore, the manufacturing cost of the fingerprint sensing device can be reduced. In addition, by using a lateral electric field to sense fingerprints, the total number of receiving circuit elements and scanning circuit elements is far less than the total number of receiving electrode elements and scanning electrode elements, so the volume of the first substrate sensing wafer can be effectively reduced, thereby reducing costs.

The specific embodiments proposed in the detailed description of the preferred embodiments are only used to facilitate the description of the technical content of the present invention, rather than limiting the present invention to the above embodiments in a narrow sense, without exceeding the spirit of the present invention and the following patent applications The scope of the scope, the implementation of various changes, all belong to the scope of the present invention.

F‧‧‧finger

PCP‧‧‧ entity coplanar

VCP‧‧‧Virtual Coplanar

10‧‧‧First substrate sensing chip

11‧‧‧ top surface

12‧‧‧ lower surface

13‧‧‧ side

15‧‧‧scan circuit element

20‧‧‧Second substrate / moulding layer

21‧‧‧ Top surface

30‧‧‧scan electrode

40‧‧‧Scan Lead

60‧‧‧Device protection layer

70‧‧‧Insulation layer group

71, 72, 73‧‧‧ Insulation

75‧‧‧ top surface

100‧‧‧ composite substrate sensing device

130‧‧‧Receiving electrode element

140‧‧‧Receiving wire

150‧‧‧Receiving circuit element

Claims (18)

A composite substrate sensing device includes at least: a first substrate sensing wafer having an upper surface, a lower surface, a plurality of sides connected to the upper surface and the lower surface, and a plurality of scanning circuits below the upper surface. And a plurality of receiving circuit elements; a second substrate connected to one or more of the side surfaces of the first substrate sensing wafer; an insulating layer group including a plurality of insulating layers located on the second substrate An upper surface and the upper surface of the first substrate sensing wafer, the upper surface of the second substrate and the upper surface of the first substrate sensing wafer are located on a virtual coplanar plane; a plurality of scanning electrode elements and A plurality of receiving electrode elements is located on an upper surface of the insulating layer group, the upper surface of the insulating layer group is located on a solid coplanar, the virtual coplanar is substantially parallel to the solid coplanar; and a plurality of scanning wires and A plurality of receiving wires are partially or wholly formed in the insulating layer group, and each of the scanning wires electrically connects one column of the scanning electrode elements to a corresponding one of the scanning circuit elements, each of which The receiving wire electrically connects one row of the receiving electrode elements to a corresponding one of the receiving circuit elements, and the scanning circuit elements send one or more scanning signals to the scanning electrode elements, so that the receiving circuit elements A change in an electric field near an object is sensed through the receiving electrode elements and the receiving wires. The composite substrate sensing device is a fingerprint sensing device, and the object is a finger. The finger can be obtained by the electric field change. Information about the difference between the ripple peaks or valleys. The composite substrate sensing device according to item 1 of the scope of the patent application, further comprising: a second substrate sensing wafer having an upper surface, a lower surface, a plurality of sides connected to the upper surface and the lower surface, and located at The second substrate senses a plurality of second scanning circuit elements and a plurality of second receiving circuit elements below the upper surface of the wafer, and the second substrate is connected to one of the side surfaces of the second substrate sensing wafer or Multiple, the insulating layer group is located on the upper surface of the second substrate, the upper surface of the first substrate sensing wafer and the upper surface of the second substrate sensing wafer; a plurality of second scanning electrode elements and A plurality of second receiving electrode elements are located on the upper surface of the insulating layer group and the upper surface of the second substrate sensing wafer; and a plurality of second scanning wires and a plurality of second receiving wires are formed in part or all In the insulating layer group, each of the second scanning wires electrically connects one of the columns of the second scanning electrode elements to a corresponding one of the second scanning circuit elements, and each of the second receiving wires connects the first Two receiving electrode elements The middle row is electrically connected to a corresponding one of the second receiving circuit elements, and the second scanning circuit elements send one or more second scanning signals to the second scanning electrode elements, so that the second receiving circuits The element, through the second receiving electrode element and the second receiving wire, cooperates with the receiving circuit element to sense the electric field change of the near object. The composite substrate sensing device according to item 1 of the patent application scope, wherein the insulating layer group includes three insulating layers. The composite substrate sensing device according to item 1 of the scope of patent application, wherein the scanning circuit elements are arranged in a one-dimensional first array, and the scanning electrode elements and the receiving electrode elements are arranged in a two-dimensional first array. Two arrays, the first array and the second array have mutually perpendicular X-axis and Y-axis, the size of the first array on the X-axis is less than or equal to the size of the second array on the X-axis, the first array The size of an array on the Y axis is less than or equal to the size of the second array on the Y axis. The composite substrate sensing device according to item 1 of the scope of patent application, wherein the scanning circuit elements are arranged in a one-dimensional first array, and the scanning electrode elements and the receiving electrode elements are arranged in a two-dimensional first array. Two arrays, the first array and the second array have mutually perpendicular X-axis and Y-axis, the size of the first array on the Y-axis is substantially equal to the size of the second array on the Y-axis, the first array The size of an array on the X axis is less than or equal to the size of the second array on the X axis. For example, the composite substrate sensing device described in item 1 of the patent application scope further includes a device protection layer located on the insulating layer group and the scanning electrode elements and the receiving electrode elements. The device protection layer directly or indirectly communicates with the device protection layer. The object is in contact. The composite substrate sensing device according to item 1 of the scope of the patent application, wherein the scanning electrode elements and the receiving electrode elements are distributed above the first substrate sensing wafer and the second substrate so that the first substrate The area of the substrate sensing wafer is minimized without sacrificing a physical sensing area of the composite substrate sensing device. The composite substrate sensing device described in item 1 of the scope of the patent application, further includes a separated conductive layer disposed between the receiving electrode elements and the receiving circuit element and coupled to a fixed potential for shielding the The receiving electrode elements and the receiving circuit elements are protected from mutual interference. The composite substrate sensing device according to item 1 of the patent application scope, wherein the second substrate surrounds the sides of the first substrate sensing wafer. The composite substrate sensing device according to item 1 of the scope of patent application, wherein the second substrate is in direct contact with one of the sides of the first substrate sensing wafer. The composite substrate sensing device according to item 1 of the scope of the patent application, wherein two adjacent scanning electrode elements and two adjacent receiving electrode elements form a sensing unit, and the size of the sensing unit ranges from 20 to Between 100 microns. A method for manufacturing a composite substrate sensing device includes at least the following steps: (a) providing a first substrate sensing wafer, the first substrate sensing wafer having an upper surface, a lower surface, connected to the upper surface, and the lower surface; A plurality of side surfaces of the surface and a plurality of scanning circuit elements and a plurality of receiving circuit elements below the upper surface; (b) providing a second substrate connected to one of the side surfaces of the first substrate sensing chip or A plurality; (c) forming an insulating layer group including a plurality of insulating layers on an upper surface of the second substrate and the upper surface of the first substrate sensing wafer, and partially or entirely located in the insulating layer group A plurality of scanning leads and a plurality of receiving leads; and (d) forming a plurality of scanning electrode elements and a plurality of receiving electrode elements on an upper surface of the insulating layer group, each scanning lead electrically charging one row of the scanning electrode elements Connected to one of the corresponding scanning circuit elements, each of the receiving wires electrically connects one row of the receiving electrode elements to a corresponding one of the receiving circuit elements, and the scanning circuit elements send Output one or more scanning signals to the scanning electrode elements, so that the receiving circuit elements sense an electric field change near the object through the receiving electrode elements and the receiving wires, wherein the composite substrate sensing device is a In a fingerprint sensing device, the object is a finger, and the difference information between the peak or valley of the finger can be obtained by the electric field change. The manufacturing method according to item 12 of the scope of patent application, wherein the step (b) includes at least: (b1) pouring the second substrate to surround the side surfaces, the upper surface, and the lower surface of the first substrate sensing wafer And (b2) performing back grinding to remove the second substrate above the upper surface of the first substrate sensing wafer. The manufacturing method according to item 13 of the scope of patent application, wherein step (b) is performed to remove a wafer protective layer on the first substrate sensing wafer until the transmission electrodes of the receiving circuit elements are exposed. . The manufacturing method described in item 12 of the patent application scope further includes the following steps: (e) forming a device protection layer on the insulating layer group, the scanning electrode elements, and the receiving electrode elements, the device protection layer and The object is in direct or indirect contact. The manufacturing method according to item 12 of the scope of patent application, wherein the step (b) includes at least: forming a groove in the second substrate; and placing the first substrate sensing wafer in the groove. The manufacturing method according to item 12 of the scope of patent application, wherein step (b) includes at least: (b1) perfusing one of the side surfaces of the second substrate connected to the first substrate sensing wafer, the upper surface and the lower surface; and (b2) performing a regrind to remove the first substrate sensing The second substrate above the upper surface of the wafer. The manufacturing method according to item 11 of the scope of patent application, wherein two adjacent scanning electrode elements and two adjacent receiving electrode elements form a sensing unit, and the size of the sensing unit is between 20 and 100 microns. between.