CN108712823B

CN108712823B - Conductive terminal, manufacturing method and binding method thereof, and binding method of circuit board

Info

Publication number: CN108712823B
Application number: CN201810491296.XA
Authority: CN
Inventors: 包潘飞
Original assignee: Wuhan China Star Optoelectronics Semiconductor Display Technology Co Ltd
Current assignee: Wuhan China Star Optoelectronics Semiconductor Display Technology Co Ltd
Priority date: 2018-05-21
Filing date: 2018-05-21
Publication date: 2020-07-24
Anticipated expiration: 2038-05-21
Also published as: CN108712823A

Abstract

The invention discloses a conductive terminal, a manufacturing method and a binding method thereof, a binding method of a circuit board and a display panel. The manufacturing method of the conductive terminal comprises the following steps: forming a conductive layer on a substrate; forming a solder layer on the conductive layer; the solder layer and the conductive layer are patterned to form a plurality of conductive terminals, wherein the conductive terminals are independent of each other. The binding method of the conductive terminal comprises the following steps: forming a first conductive terminal and a second conductive terminal on the first substrate and the second substrate respectively by using the manufacturing method; aligning the first substrate and the second substrate, and attaching the first conductive terminals and the second conductive terminals to each other; and heating the first conductive terminal and the second conductive terminal to enable the first soldering layer of the first conductive terminal and the second soldering layer of the second conductive terminal to be mutually welded. The conductive terminals on the two sides are connected by a welding method so as to improve the corrosion resistance of the conductive terminals.

Description

Conductive terminal, manufacturing method and binding method thereof, and binding method of circuit board

Technical Field

The invention belongs to the technical field of electronics, and particularly relates to a conductive terminal, a manufacturing method and a binding method thereof, a binding method of a circuit board, and a display device.

Background

However, for the current market, the screen occupation ratio is gradually increased, the non-display area available for transmitting signals is gradually reduced, and therefore the effective binding area needs to be increased in the smaller non-display area.

For the current bonding process, the bonding is mainly performed by using an Anisotropic Conductive Film (ACF) 100 as an intermediate material, as shown in fig. 1. For the current binding process, there are two drawbacks: (1) the free movement of the conductive particles 200 may cause a poor vertical conduction of the terminals 300 or a short circuit between the left and right terminals 300; (2) due to the existence of the ACF 100, the effective connection area on the non-display area terminal is reduced, and the ACF is not suitable for the development trend of the future display industry. (3) The prior ACF 100 has poor corrosion resistance and is easy to be corroded by water and oxygen. Therefore, under the condition that the terminal can be normally conducted, the effective binding area and the corrosion resistance of the bound terminal are increased, and the method has important significance for the development of the future display industry.

Disclosure of Invention

In order to solve the defects of the prior art, the invention aims to provide a conductive terminal with strong corrosion resistance, a manufacturing method and a binding method thereof, a binding method of a circuit board and a display device.

In order to achieve the purpose, the invention adopts the following technical scheme:

a method for manufacturing a conductive terminal comprises the following steps:

forming a conductive layer on a substrate;

forming a solder layer on the conductive layer;

patterning the solder layer and the conductive layer to form a plurality of conductive terminals, wherein the conductive terminals are independent of each other.

Preferably, the specific method for etching the soldering layer and the conductive layer to form a plurality of conductive terminals includes:

forming a photoresist layer on the brazing layer;

exposing the photoresist layer by using a photomask with a preset pattern;

developing and etching the exposed photoresist layer to form a patterned photoresist layer;

etching the conducting layer which is not covered by the patterned photoresist layer;

and stripping off the patterned photoresist layer.

Preferably, the brazing layer is made of SnAgCu.

Preferably, the conductive layer comprises a first titanium layer, an aluminum layer and a second titanium layer which are sequentially stacked.

The invention also discloses a binding method of the conductive terminal, which comprises the following steps:

forming a first conductive terminal and a second conductive terminal on the first substrate and the second substrate respectively by using any one of the above manufacturing methods;

aligning the first substrate and the second substrate, and attaching the first conductive terminals and the second conductive terminals to each other;

heating the first and second conductive terminals so that the first and second solder layers of the first and second conductive terminals are welded to each other.

Preferably, the material of the first brazing layer and/or the second brazing layer contains a corrosion resistant element.

Preferably, the first and second conductive terminals are heated using an induction heating device.

The invention also discloses a binding method of the circuit board, which comprises the following steps:

and forming a first conductive terminal and a second conductive terminal in the first binding region of the display panel and the second binding region of the circuit board respectively by using any one of the above manufacturing methods.

Aligning the display panel and the circuit board to each other, and attaching the first conductive terminals and the second conductive terminals to each other;

heating the first and second conductive terminals such that the first and second solder layers of the first and second conductive terminals are soldered to each other.

The invention also discloses a conductive terminal which comprises a conductive layer and a brazing layer arranged on the conductive layer.

The invention also discloses a display device, which comprises a display panel, a circuit board and a plurality of conductive connecting ends, wherein the plurality of conductive connecting ends are independent from each other, the display panel comprises a first binding area, the circuit board comprises a second binding area, and the first binding area and the second binding area are connected and bound through the conductive connecting ends, wherein the conductive connecting ends comprise a first conductive layer arranged in the first binding area, a second conductive layer arranged in the second binding area and a welding layer arranged between the first conductive layer and the second conductive layer.

Has the advantages that: according to the conductive terminals, the manufacturing method and the binding method of the conductive terminals, the binding method of the circuit board and the display device, the brazing layer is formed on each conductive terminal through the patterning process, the conductive terminals are convenient to weld at the later stage, and the manufacturing method is simple in process and low in cost. According to the conductive terminal binding method provided by the embodiment of the invention, the conductive terminals on two sides are connected by a welding method, so that the terminals on two sides are ensured to be mutually communicated, and meanwhile, the adjacent conductive terminals can be prevented from being short-circuited.

Drawings

FIG. 1 is a diagram illustrating a binding state of a conductive terminal in the prior art;

fig. 2 is a flowchart of a method for manufacturing conductive terminals according to a first embodiment of the invention;

fig. 3A to 3C are process diagrams of conductive terminals according to a first embodiment of the invention;

fig. 4A to 4D are process flow diagrams of patterning processes of a conductive layer and a solder layer according to a first embodiment of the invention;

FIG. 5 is a flowchart of a method for binding conductive terminals according to a third embodiment of the present invention;

fig. 6A to 6D are process flow diagrams of a method for binding conductive terminals according to a third embodiment of the present invention;

fig. 7 is a schematic diagram of a circuit board binding state according to a fourth embodiment of the present invention;

fig. 8 is a schematic cross-sectional view of a display device according to a fifth embodiment of the invention.

Detailed Description

In order to make the objects, technical solutions and advantages of the present invention more apparent, the present invention is further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the invention and are not intended to limit the invention.

Example one

Fig. 2 shows a flow chart of a method of fabricating a conductive terminal according to an embodiment of the invention, the method of fabricating including steps one to three:

specifically, the first step: referring to fig. 3A, a conductive layer 20 is formed on a substrate 10.

Further, the substrate 10 in this embodiment may be a substrate in a display panel, a metal terminal is provided on the substrate 10, and the conductive layer 20 covers and contacts the metal terminal. Further, the conductive layer 20 is preferably deposited on the substrate 10 by a magnetron sputtering process, but other physical vapor deposition methods may be used to form the conductive layer 20. As a preferred embodiment, the conductive layer 20 includes a first titanium layer 20a, an aluminum layer 20b, and a second titanium layer 20c, which are sequentially stacked.

Step two: referring to fig. 3B, a solder layer 30 is formed on the conductive layer 20.

As a preferred embodiment, a magnetron sputtering process is used to deposit and form the brazing layer 30 on the conductive layer 20, and the material of the brazing layer 30 is preferably Sn-based solder, i.e. SnAgCu, which is an eutectic composition, i.e. its melting point is lower than that of Sn, so that the temperature during welding can be reduced, not only the efficiency can be improved, but also the risk of damage to the substrate can be reduced. In other embodiments, the material of the solder layer 30 may be other low-temperature solder, which can reduce the heating temperature of the solder layer 30 and prevent the device from being damaged by high temperature.

Step three: referring to fig. 3C, the solder layer 30 and the conductive layer 20 are patterned to form a plurality of conductive terminals 40, wherein the plurality of conductive terminals 40 are independent of each other.

As a preferred embodiment, the third step includes a first step to a fourth step:

specifically, the first step is as follows: referring to fig. 4A, a photoresist layer 50 is formed on the solder layer 30.

Step three: referring to fig. 4B, a yellow process is applied to the photoresist layer 50 to form a blocking layer 50 a. Further, a photoresist layer 50 is coated on the solder layer 30, the photoresist layer 50 is exposed using a mask 60 having a predetermined pattern, and the exposed photoresist layer 50 is developed and etched to form a patterned photoresist layer 50 a.

Step three: referring to fig. 4C, the conductive layer 20 not covered by the patterned photoresist layer 50a is etched. The solder layer 30 and the conductive layer 20 are etched according to the patterned photoresist layer 50a to form a plurality of conductive terminals 40. As a preferred embodiment, the solder layer 30 and the conductive layer 20 are etched by a dry etching process to form a plurality of conductive terminals 40 arranged at intervals, and each conductive terminal 40 includes the conductive layer 20 and the solder layer 30.

Step three and four: referring to fig. 4D, the patterned photoresist layer 50a is stripped and removed.

According to the manufacturing method of the conductive terminals, the brazing layer is formed on each conductive terminal through the etching process, so that the conductive terminals can be conveniently welded at the later stage, and the manufacturing method is simple in process and low in cost.

Example two

As shown in fig. 4D, the conductive terminal 40 according to the present embodiment includes the conductive layer 20 and the solder layer 30 provided on the conductive layer 20. As a preferred embodiment, the conductive terminal 40 is manufactured by the manufacturing method of the first embodiment.

EXAMPLE III

Fig. 5 shows a flowchart of a binding method of a conductive terminal according to an embodiment of the invention, the binding method including steps S1 to S3:

specifically, step S1: referring to fig. 6A and 6B, a first substrate 11 and a second substrate 12 are provided, and a first conductive terminal 41 is formed on the first substrate 11 and a second conductive terminal 42 is formed on the second substrate 12, respectively, according to the manufacturing method of the first embodiment.

Step S2: referring to fig. 6C, the first substrate 11 and the second substrate 12 are aligned, and the first conductive terminals 41 and the second conductive terminals 42 are attached to each other. Specifically, the first substrate 11 and the second substrate 12 are grasped by a robot, so that the first conductive terminal 41 and the second conductive terminal 42 are aligned and attached, and then the first conductive terminal 41 and the second conductive terminal 42 are pressed together, so that the two terminals do not move relatively.

Step S3: referring to fig. 6D, the first and second

conductive terminals

41 and 42 are heated such that the first and second soldering layers of the first and second

conductive terminals

41 and 42 are welded to each other. As a preferred embodiment, the induction heating device 400 is used to heat the first conductive terminal 41 and the second conductive terminal 42, and since the induction heating device 400 can realize rapid heating, the first solder layer and the second solder layer are melted rapidly and then fused to form the bonding layer 70, so that the first conductive terminal 41 and the second conductive terminal 42 are welded to each other and conducted to each other. To avoid damage to other parts of the device, the induction heating unit 400 only needs to heat the parts where the first conductive terminal 41 and the second conductive terminal 42 are located.

Further, in order to improve the corrosion resistance of the first conductive terminal 41 and the second conductive terminal 42, corrosion-resistant elements, such as Nb, Ni, and the like, are added to the materials of the first soldering layer and the second soldering layer, so that the corrosion resistance of the bound first conductive terminal 41 and the bound second conductive terminal 42 is improved, a subsequent gluing process can be omitted, and the production efficiency is improved.

According to the conductive terminal binding method provided by the embodiment of the invention, the conductive terminals on two sides are connected by a welding method, so that the terminals on two sides are ensured to be mutually communicated, and meanwhile, the adjacent conductive terminals can be prevented from being short-circuited.

Example four

The method for binding circuit boards according to the embodiment of the invention includes steps S10 to S30:

specifically, step S10: referring to fig. 7, a display panel 80 and a circuit board 90 are provided, the display panel 80 including a first bonding region and a plurality of first terminals 81 disposed in the first bonding region, the plurality of first terminals 81 being disposed at intervals, the circuit board 90 including a second bonding region and a plurality of second terminals 91 disposed in the second bonding region, the plurality of second terminals 91 being disposed at intervals.

Step S20: according to the manufacturing method of the first embodiment, a plurality of first conductive terminals 41 are formed on the first bonding region and a plurality of second conductive terminals 42 are formed on the second bonding region, wherein the plurality of first conductive terminals 41 are respectively in corresponding contact with the plurality of first terminals 81, and the plurality of second conductive terminals 42 are respectively in corresponding contact with the plurality of second terminals 91.

Step S30: the display panel 80 and the circuit board 90 are aligned, and the first conductive terminals 41 and the second conductive terminals 42 are attached to each other.

Step S40: the first and second

conductive terminals

41 and 42 are heated so that the first and second solder layers of the first and second

conductive terminals

41 and 42 are welded to each other.

As a preferred embodiment, the induction heating device 400 is used to heat the first conductive terminal 41 and the second conductive terminal 42, and since the induction heating device 400 can realize rapid heating, the first solder layer and the second solder layer are melted rapidly and then fused to form the bonding layer 70, so that the first conductive terminal 41 and the second conductive terminal 42 are welded to each other and conducted to each other. In order to avoid damage to other parts of the display panel, the induction heating device 400 only needs to heat the portions of the first conductive terminals 41 in the first binding region and the second conductive terminals 42 in the second binding region.

In order to improve the corrosion resistance of the first conductive terminal 41 and the second conductive terminal 42, corrosion resistant elements, such as Nb, Ni, and the like, are added to the materials of the first solder layer and the second solder layer, so that the corrosion resistance of the bound first conductive terminal 41 and the bound second conductive terminal 42 is provided, a subsequent gluing process can be omitted, and the production efficiency is improved.

EXAMPLE five

As shown in fig. 8, the display device according to the present embodiment includes a display panel 80, a circuit board 90, and a conductive connection terminal 500, the display panel 80 includes a first bonding region and a plurality of first terminals 81 disposed in the first bonding region, the plurality of first terminals 81 are disposed at intervals, the circuit board 90 includes a second bonding region and a plurality of second terminals 91 disposed in the second bonding region, and the plurality of second terminals 91 are disposed at intervals. The first bonding region and the second bonding region are connected and bonded by a plurality of conductive connection terminals 500, the plurality of conductive connection terminals 500 are independent of each other, wherein the conductive connection terminals 500 include a first conductive layer 21 disposed in the first bonding region, a second conductive layer 22 disposed in the second bonding region, and a solder layer 23 disposed between the first conductive layer 21 and the second conductive layer 22. Further, the first conductive layer 21 is connected to the first terminal 81, and the second conductive layer 22 is connected to the second terminal 91.

The display device in the embodiment connects and binds the first conducting layer and the second conducting layer through the welding layer, ensures good conductivity between the first conducting layer and the second conducting layer, improves the corrosion resistance of the conductive connecting end, and does not need to bind the first conducting layer and the second conducting layer through ACF glue.

Although a few embodiments of the present invention have been shown and described, it would be appreciated by those skilled in the art that changes may be made in these embodiments without departing from the principles and spirit of the invention, the scope of which is defined in the claims and their equivalents, and that such changes and modifications are intended to be within the scope of the invention.

Claims

1. A method of binding conductive terminals, comprising:

forming a first conductive terminal (41) and a second conductive terminal (42) on the first substrate (11) and the second substrate (12) respectively by using a conductive terminal manufacturing method;

aligning the first substrate (11) and the second substrate (12), and attaching the first conductive terminals (41) and the second conductive terminals (42) to each other;

heating the first conductive terminal (41) and the second conductive terminal (42) so as to enable a first soldering layer (31) of the first conductive terminal (41) and a second soldering layer (32) of the second conductive terminal (42) to be mutually welded, wherein only the part where the first conductive terminal (41) and the second conductive terminal (42) are located is heated by an induction heating device;

the manufacturing method of the conductive terminal comprises the following steps:

forming a conductive layer (20) on a substrate (10);

forming a solder layer (30) on the conductive layer (20);

patterning the solder layer (30) and the conductive layer (20) to form a plurality of conductive terminals (40), wherein the conductive terminals (40) are independent of each other;

the brazing layer (30) is made of low-temperature material;

the specific method for patterning the brazing layer (30) and the conductive layer (20) comprises the following steps:

coating a photoresist layer (50) on the brazing layer (30);

exposing the photoresist layer (50) by using a photomask (60) with a predetermined pattern;

developing and etching the exposed photoresist layer (50) to form a patterned photoresist layer (50 a);

etching the conductive layer (20) not covered by the patterned photoresist layer (50 a);

and stripping off the patterned photoresist layer.

2. The method for binding conductive terminals according to claim 1, wherein the conductive layer (20) comprises a first titanium layer (20a), an aluminum layer (20b) and a second titanium layer (20c) sequentially stacked.

3. The method for binding conductive terminals according to claim 2, wherein the solder layer (30) is made of SnAgCu.

4. The method for binding electrically conductive terminals according to claim 1, characterized in that the first brazing layer (31) and/or the second brazing layer (32) is made of a material having a corrosion resistant element.

5. A method for binding circuit boards is characterized by comprising the following steps:

respectively forming a first conductive terminal (41) and a second conductive terminal (42) in a first binding region of a display panel (80) and a second binding region of a circuit board (90) by using a conductive terminal manufacturing method;

aligning the display panel (80) and the circuit board (90), and attaching the first conductive terminal (41) and the second conductive terminal (42) to each other;

forming a conductive layer (20) on a substrate (10);

forming a solder layer (30) on the conductive layer (20);

the brazing layer (30) is made of low-temperature material;

coating a photoresist layer (50) on the brazing layer (30);

and stripping off the patterned photoresist layer.

6. The circuit board bonding method according to claim 5, wherein the conductive layer (20) comprises a first titanium layer (20a), an aluminum layer (20b), and a second titanium layer (20c) sequentially stacked.

7. The circuit board bonding method according to claim 6, wherein the solder layer (30) is made of SnAgCu.