Manufacturing method of multilayer piezoelectric composite material sensing and driving integrated electrode bonding pad

Abstract

The invention relates to a manufacturing method of a multilayer piezoelectric composite material sensing and driving integrated electrode bonding pad, and belongs to the technical field of sensors. The packaging structure comprises an insulation packaging layer, and the insulation packaging layer is internally provided with a first driving function layer group, an induction function layer group, a second driving function layer group and a third driving function layer group which are sequentially arranged from bottom to top; each of the first to third driving function layer groups comprises a first flexible insulating layer, a first conductive layer, a first piezoelectric composite material layer, a second conductive layer and a second flexible insulating layer which are sequentially arranged from bottom to top; in the first to third driving function layers, all first bonding pad center holes are coaxially arranged, and a general driving terminal negative electrode bonding pad is formed through filling, sintering and connecting of conductive slurry; and all the second bonding pad center holes are coaxially arranged, and are filled with conductive paste, sintered and connected to form a total driving terminal positive electrode bonding pad. And the integrated packaging of the device structure is also realized while multiple layers of bonding pads are overlapped, interconnected and led out in the vertical direction.

Description

Technical Field

[0001] The present invention relates to the field of sensor technology, and in particular to a method for manufacturing a multi-layer piezoelectric composite material sensing-driven integrated electrode pad. Background Art

[0002] Piezoelectric sensor is a sensor based on the piezoelectric effect. It works by using the phenomenon that certain dielectrics deform after being subjected to external forces, thereby generating charges on their surfaces. This sensor is mainly composed of piezoelectric sensing elements and measurement conversion circuits. Piezoelectric sensing elements are force-sensitive elements that can measure physical quantities that can be converted into forces, such as stress, pressure, vibration, acceleration, etc. Piezoelectric materials can be divided into piezoelectric single crystals, piezoelectric polycrystals, and organic piezoelectric materials. Among them, various piezoelectric ceramics of piezoelectric polycrystals and quartz crystals of piezoelectric single crystals are the most widely used in piezoelectric sensors.

[0003] At present, in conventional piezoelectric sensor structures, the ordinary comb-shaped electrode network is a planar shape, and can only make two driving electrode pads, but cannot make a separate sensing layer electrode pad. For multi-layer piezoelectric composite material sensing-drive integrated conformal devices, it is impossible to solve the problem of multi-layer isolation, superposition and interconnection of sensing electrodes and driving electrodes. The existing structure does not meet its lead-out function requirements and process processing requirements. Summary of the invention

[0004] The purpose of the present invention is to provide a method for manufacturing a multi-layer piezoelectric composite material sensing-driven integrated electrode pad. The invention superimposes the two electrode multi-layer pads of the driving layer of the sensing-driven integrated conformal device, with a coaxial through hole in the middle, and connects the corresponding pads together by filling the through hole with a conductive paste and sintering. The sensing electrode pad is led out as a separate layer of the sensing layer. While the driving electrode, piezoelectric material, insulating layer and other multi-layer isolations are stacked and led out, the device structure is also integrated and packaged.

[0005] It adopts the following technical solutions: A method for manufacturing a multilayer piezoelectric composite material sensing-driven integrated electrode pad; a multilayer piezoelectric composite material sensing-driven integrated electrode pad structure is used, the structure includes an insulating packaging layer, and the insulating packaging layer has a first driving function layer group, a sensing function layer group, a second driving function layer group and a third driving function layer group arranged in sequence from bottom to top; The first to third driving function layer groups each include a first flexible insulating layer, a first conductive layer, a first piezoelectric composite material layer, a second conductive layer, and a second flexible insulating layer, which are arranged in sequence from bottom to top; One side of the first flexible insulating layer has a protruding first pad substrate lead-out portion, the first pad substrate lead-out portion is provided with a first through hole, the first conductive layer is provided with a first pad connected to the first pad substrate lead-out portion, the first pad has a center hole, the center hole and the first through hole are coaxially arranged and equal in size, and the first pad serves as a common negative electrode of the driving terminal and the sensing function terminal; One side of the second flexible insulating layer has a protruding second pad substrate lead-out portion, the first and second pad substrate lead-out portions are arranged opposite to each other, a second through hole is arranged on the second pad substrate lead-out portion, a second pad 241 connected to the second pad substrate lead-out portion is arranged on the second conductive layer, the second pad has a center hole, the center hole is coaxially arranged with the second through hole and has the same size, and the second pad serves as the positive electrode of the driving terminal; The sensing function layer group comprises a third flexible insulating layer, a third conductive layer and a second piezoelectric composite material layer arranged in sequence from bottom to top; one side of the third flexible insulating layer has a protruding third pad substrate lead-out portion, and in the vertical projection direction, the third pad substrate lead-out portion is at a certain distance from the first and second pad substrate lead-out portions and does not contact each other, and the third conductive layer is provided with a third pad connected to the third pad substrate lead-out portion, and the third pad serves as the positive electrode of the sensing function terminal; Among them, in the first to third driving function layers, all the center holes of the first pads are coaxially arranged, and are connected by filling and sintering with conductive paste to form the negative electrode pad of the total driving terminal; all the center holes of the second pads are coaxially arranged, and are connected by filling and sintering with conductive paste to form the positive electrode pad of the total driving terminal; The method comprises the following steps: S1, using a flexible insulating material as a substrate to respectively manufacture the first to third flexible insulating layers, using a piezoelectric composite material as a substrate to respectively manufacture the first and second piezoelectric composite material layers, and using a conductive paste as a conductive material to print and sinter the corresponding conductive layers on the first to third flexible insulating layers; S2, connecting the first conductive layer with the first flexible insulating layer and the second conductive layer with the second flexible insulating layer to the upper and lower surfaces of the first piezoelectric composite material layer through flexible conductive adhesives, respectively, to form first to third driving functional layers; connecting the third conductive layer with the third flexible insulating layer to the second piezoelectric composite material layer through flexible conductive adhesives, to form a sensing functional layer group; S3, sequentially gluing the first driving function layer group, the sensing function layer group, the second driving function layer group and the third driving function layer group together; wherein all the center holes of the first pads are vertically coaxially aligned, and all the center holes of the second pads are also vertically coaxially aligned; S4, filling the central holes of all the first pads with conductive paste and sintering them to form a negative pad of the total driving terminal, and filling the central holes of all the second pads with conductive paste and sintering them to form a positive pad of the total driving terminal; S5. Insulating glue is provided on the exposed surfaces of the above layers to form an insulating packaging layer, and the device is packaged as a whole.

[0006] Furthermore, the first to third flexible insulating layers are insulating layers with PI polyimide resin as the base material.

[0007] Furthermore, the first to third flexible insulating layers are all rectangular, the first pad substrate lead-out portion and the second pad substrate lead-out portion are arranged diagonally opposite to each other in a rectangle; the first pad substrate lead-out portion and the third pad substrate lead-out portion are arranged opposite to each other in a straight line.

[0008] Furthermore, the conductive paste is gold paste.

[0009] Compared with the prior art, the present invention has the following beneficial effects: The present invention arranges the positions of the first to third pad substrate lead-out parts so that the third pad substrate lead-out part is at a certain distance from the first and second pad substrate lead-out parts in the vertical projection direction and does not contact each other, so that the multi-layer pads are vertically superimposed, and the corresponding pads are connected by conductive paste. While the multi-layer isolation, superposition and interconnection of the sensing electrode and the driving electrode are conducted, the device structure is also packaged in an integrated manner. BRIEF DESCRIPTION OF THE DRAWINGS

[0010] Figure 1 It is a schematic diagram of the structure of a multi-layer piezoelectric composite material with an integrated sensing and driving electrode pad of the present invention; Figure 2 yes Figure 1 A top view of Figure 3 yes Figure 2 Schematic diagram of the cross-sectional structure along the AA direction.

[0011] Explanation of the reference numerals: 100, insulating packaging layer; 200, first driving function layer group; 210, first flexible insulating layer; 211, first pad substrate lead-out portion; 212, first through hole; 220, first conductive layer; 221, first pad; 230, first piezoelectric composite material layer; 240, second conductive layer; 241, second pad; 250, second flexible insulating layer; 251, second pad substrate lead-out portion; 252, second through hole; 300, sensing function layer group; 310, third flexible insulating layer; 311, third pad substrate lead-out portion; 320, third conductive layer; 321, third pad; 330, second piezoelectric composite material layer; 400, second driving function layer group; 500, third driving function layer group; 600, negative electrode pad of the total driving terminal; 700, positive electrode pad of the total driving terminal. DETAILED DESCRIPTION

[0012] To make the present invention more clear, a method for manufacturing a multilayer piezoelectric composite material sensing-driven integrated electrode pad of the present invention is further described below in conjunction with the accompanying drawings. The specific embodiments described here are only used to explain the present invention and are not used to limit the present invention.

[0013] A method for manufacturing a multi-layer piezoelectric composite material sensing drive integrated electrode pad, using a multi-layer piezoelectric composite material sensing drive integrated electrode pad structure, specifically as follows Figures 1 to 3 As shown, a multi-layer piezoelectric composite material sensing-driven conformal device structure includes a three-dimensional insulating packaging layer 100, and the insulating packaging layer 100 is coated with a first driving function layer group 200, a sensing function layer group 300, a second driving function layer group 400 and a third driving function layer group 500 which are sequentially connected from bottom to top. The first to third driving function layer groups each include a first flexible insulating layer 210, a first conductive layer 220, a first piezoelectric composite material layer 230, a second conductive layer 240 and a second flexible insulating layer 250 which are sequentially arranged from bottom to top.

[0014] The first flexible insulating layer 210 is made of high-quality flexible insulating material as a substrate, and serves as a substrate for the first conductive layer 220 . One side of the first flexible insulating layer 210 has a protruding first pad substrate lead-out portion 211 , and the first pad substrate lead-out portion 211 is provided with a through first through hole 212 .

[0015] The first conductive layer 220 uses conductive paste as the conductive material, is made on the first flexible insulating layer 210 and has a first pad 221 as its lead-out end. The first pad 221 has a center hole, which is coaxially arranged with the first through hole 212 and is equal in size. The first pad 221 serves as a common negative electrode for the driving terminal and the sensing function terminal.

[0016] The first piezoelectric composite material layer 230 is made of piezoelectric composite material and has no lead terminals.

[0017] The second flexible insulating layer 250 is also made of a high-quality flexible insulating material as a substrate, and serves as a substrate for the second conductive layer 240. One side of the second flexible insulating layer 250 has a protruding second pad substrate lead-out portion 251. The first and second pad substrate lead-out portions are arranged opposite to each other, that is, in the vertical projection direction, the first and second pad substrate lead-out portions are at a certain distance from each other and do not contact each other. In this example, the first and second flexible insulating layers are both rectangular. Preferably, the first pad substrate lead-out portion 211 and the second pad substrate lead-out portion 251 are arranged diagonally opposite to each other in a rectangular shape, so that the first and second pad substrate lead-out portions are separated as much as possible to avoid electrical interconnection in subsequent processes. The second pad substrate lead-out portion 251 is provided with a second through hole 252.

[0018] The second conductive layer 240 uses conductive paste as the conductive material, is made under the second flexible insulating layer 250 and has a second solder pad 241 as its lead end. The second solder pad 241 has a center hole, which is coaxially arranged with the second through hole 252 and equal in size. The second solder pad 241 serves as the positive electrode of the driving terminal.

[0019] The sensing functional layer group 300 includes a third flexible insulating layer 310 , a third conductive layer 320 , and a second piezoelectric composite material layer 330 which are sequentially connected from bottom to top.

[0020] Among them, the third flexible insulating layer 310 is also made of high-quality flexible insulating material as the base material. The substrate of the second conductive layer 240 is rectangular as a whole, and one side of the third pad substrate lead-out portion 311 is provided. In the vertical projection direction, the third pad substrate lead-out portion 311 is at a certain distance from the first and second pad substrate lead-out portions and does not contact each other. Preferably, the third pad substrate lead-out portion 311 is arranged opposite to the first pad substrate lead-out portion 211 in a straight line, that is, the third pad substrate lead-out portion 311 is located at a straight line 180 degrees symmetrical to the first pad substrate lead-out portion 211.

[0021] The third conductive layer 320 is provided with a third pad 321 connected to the third pad substrate lead-out portion 311 , and the third pad 321 serves as the positive electrode of the sensing functional terminal. The second piezoelectric composite material layer 330 has the same structure as the first piezoelectric composite material layer 230 .

[0022] In the first to third driving function layers, the center holes of all the first pads 221 are coaxially arranged, and are connected by filling and sintering with conductive paste to form the total driving terminal negative electrode pad 600; the center holes of all the second pads 241 are coaxially arranged, and are connected by filling and sintering with conductive paste to form the total driving terminal positive electrode pad 700. Of course, the total driving terminal negative electrode pad 600, the total driving terminal positive electrode pad 700 and the positive electrode of the sensing function terminal should have an area that exposes the insulating packaging layer 100, so as to facilitate electrical connection with external devices.

[0023] In this embodiment, the first to third flexible insulating layers are preferably insulating layers with PI polyimide resin as the base material; and the conductive paste is preferably gold paste.

[0024] The present application also provides a method for manufacturing a multilayer piezoelectric composite material sensing-driven integrated conformal device structure, which uses the multilayer piezoelectric composite material sensing-driven integrated conformal device structure, and comprises the following steps: S1, using a flexible insulating material as a substrate to form corresponding first to third flexible insulating layers by cutting them according to specific shapes, using a piezoelectric composite material as a substrate to form corresponding first and second piezoelectric composite material layers by cutting them according to specific shapes, and printing and sintering corresponding conductive layers on the first to third flexible insulating layers using conductive paste as a conductive material; S2. The first conductive layer 220 with the first flexible insulating layer 210 and the second conductive layer 240 with the second flexible insulating layer 250 are respectively connected to the upper and lower surfaces of the first piezoelectric composite material layer 230 through flexible conductive adhesive to form the first to third driving functional layers; the third conductive layer 320 with the third flexible insulating layer 310 is connected to the second piezoelectric composite material layer 330 through flexible conductive adhesive to form a sensing functional layer group 300.

[0025] S3, sequentially glue and connect the first driving function layer group 200, the sensing function layer group 300, the second driving function layer group 400 and the third driving function layer group 500 into one body, and note that the center holes of all the first pads 221 are vertically coaxially aligned, and the center holes of all the second pads 241 are also vertically coaxially aligned. Here, the above-mentioned center holes can be positioned and aligned by corresponding equipment or tooling.

[0026] S4. Fill the central holes of all the first pads 221 with conductive paste and sinter them to form the total drive terminal negative pad 600, and fill the central holes of all the second pads 241 with conductive paste and sinter them to form the total drive terminal positive pad 700. Here, the filling and positioning of the conductive paste is mainly achieved by the existing hole filling equipment, and the hole filling equipment ensures that the conductive paste will not overflow when filling the corresponding central holes, thereby ensuring the conduction performance of the positive and negative pads of the total drive terminal.

[0027] S5. Finally, insulating glue is provided on the exposed surfaces of the above layers to form an insulating packaging layer 100 to package the device as a whole.

[0028] The above embodiments of the present invention are merely examples for clearly illustrating the present invention, and are not intended to limit the embodiments of the present invention. For those skilled in the art, other different forms of changes or modifications can be made based on the above description. It is not necessary and impossible to list all the embodiments here. However, these obvious changes or modifications derived from the essential spirit of the present invention still fall within the scope of protection of the present invention.

Claims

1. A method for manufacturing a multilayer piezoelectric composite material sensing-drive integrated electrode pad, characterized in that; A multi-layer piezoelectric composite material sensing-driven integrated electrode pad structure is used, the structure comprising an insulating packaging layer (100), wherein the insulating packaging layer (100) has a first driving function layer group (200), a sensing function layer group (300), a second driving function layer group (400) and a third driving function layer group (500) arranged in sequence from bottom to top; The first to third driving function layer groups each comprise a first flexible insulating layer (210), a first conductive layer (220), a first piezoelectric composite material layer (230), a second conductive layer (240) and a second flexible insulating layer (250) which are arranged in sequence from bottom to top; The first flexible insulating layer (210) has a protruding first pad substrate lead-out portion (211) on one side, the first pad substrate lead-out portion (211) is provided with a first through hole (212), the first conductive layer (220) is provided with a first pad (221) connected to the first pad substrate lead-out portion (211), the first pad (221) has a center hole, the center hole and the first through hole (212) are coaxially arranged and have the same size, and the first pad (221) serves as a common negative electrode for the driving terminal and the sensing function terminal; The second flexible insulating layer (250) has a protruding second pad substrate lead-out portion (251) on one side, the first and second pad substrate lead-out portions are arranged opposite to each other, a second through hole (252) is provided on the second pad substrate lead-out portion (251), the second conductive layer (240) is provided with a second pad 241 () connected to the second pad substrate lead-out portion (251), the second pad (241) has a center hole, the center hole and the second through hole (252) are coaxially arranged and have the same size, and the second pad (241) serves as the positive electrode of the driving terminal; The sensing function layer group (300) comprises a third flexible insulating layer (310), a third conductive layer (320) and a second piezoelectric composite material layer (330) which are arranged in sequence from bottom to top; one side of the third flexible insulating layer (310) is provided with a protruding third pad substrate lead-out portion (311); in the vertical projection direction, the third pad substrate lead-out portion (311) is at a certain distance from the first and second pad substrate lead-out portions and does not contact each other; the third conductive layer (320) is provided with a third pad (321) connected to the third pad substrate lead-out portion (311); the third pad (321) serves as the positive electrode of the sensing function terminal; Among them, in the first to third driving function layers, the central holes of all the first pads (221) are coaxially arranged, and are connected by filling with conductive paste and sintering to form a total driving terminal negative electrode pad (600); the central holes of all the second pads (241) are coaxially arranged, and are connected by filling with conductive paste and sintering to form a total driving terminal positive electrode pad (700); The method comprises the following steps: S1, using a flexible insulating material as a substrate to respectively manufacture the first to third flexible insulating layers, using a piezoelectric composite material as a substrate to respectively manufacture the first and second piezoelectric composite material layers, and using a conductive paste as a conductive material to print and sinter the corresponding conductive layers on the first to third flexible insulating layers; S2, connecting the first conductive layer (220) with the first flexible insulating layer (210) and the second conductive layer (240) with the second flexible insulating layer (250) to the upper and lower surfaces of the first piezoelectric composite material layer (230) via flexible conductive adhesive, respectively, to form first to third driving functional layers; connecting the third conductive layer (320) with the third flexible insulating layer (310) to the second piezoelectric composite material layer (330) via flexible conductive adhesive, to form a sensing functional layer group (300); S3, sequentially gluing and connecting the first driving function layer group (200), the sensing function layer group (300), the second driving function layer group (400) and the third driving function layer group (500) into one body; wherein the center holes of all the first pads (221) are vertically coaxially aligned, and the center holes of all the second pads (241) are also vertically coaxially aligned; S4, filling the central holes of all the first pads (221) with conductive paste and sintering them to form a total drive terminal negative electrode pad (600), and filling the central holes of all the second pads (241) with conductive paste and sintering them to form a total drive terminal positive electrode pad (700); S5. Insulating glue is provided on the exposed surfaces of the above-mentioned layers to form an insulating packaging layer (100), and the device is packaged as a whole.

2. The method for manufacturing a multilayer piezoelectric composite material sensing-drive integrated electrode pad according to claim 1, characterized in that: The first to third flexible insulating layers are insulating layers with PI polyimide resin as a base material.

3. A method for manufacturing a multilayer piezoelectric composite material sensing-drive integrated electrode pad according to claim 1 or 2, characterized in that: The first to third flexible insulating layers are all rectangular in shape; the first pad substrate lead-out portion (211) and the second pad substrate lead-out portion (251) are arranged diagonally opposite to each other in a rectangle; and the first pad substrate lead-out portion (211) and the third pad substrate lead-out portion (311) are arranged opposite to each other in a straight line.

4. A method for manufacturing a multilayer piezoelectric composite material sensing-drive integrated electrode pad according to claim 1, characterized in that: The conductive paste is gold paste.

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