阅读说明：本技术 一种微显示焊线方法及和焊线设备 (Micro-display wire welding method and wire welding equipment ) 是由 何光友 乔辉 叶成 路晓祥 于 2019-09-25 设计创作，主要内容包括：本发明揭示了一种微显示焊线方法,PCB板具有需要焊线的区域,准备能够吹出热风的热风管,将热风管的出风口对准焊线的区域持续利用热风对焊线的区域进行加热,直至焊线的区域加热到所需温度,再将焊线的两端焊接在焊线的区域。本发明的优点在于：1、只对焊线位置进行加热,有效避开一些不能耐温的元器件；2、电器元器件在PCB背部,不需要背面加热,可以不需要加热平台,很好保护了基板上的元器件3、因为只对焊线区域加热及加热平台去除,基板可以增加更多的电路器件。(The invention discloses a micro-display wire welding method.A PCB is provided with a region needing wire welding, a hot air pipe capable of blowing hot air is prepared, an air outlet of the hot air pipe is aligned with the region of the wire welding, the hot air is continuously utilized to heat the region of the wire welding until the region of the wire welding is heated to the required temperature, and then two ends of the wire welding are welded in the region of the wire welding. The invention has the advantages that: 1. only the position of the welding wire is heated, and some components which cannot resist temperature are effectively avoided; 2. the electrical components are arranged on the back of the PCB, back heating is not needed, a heating platform is not needed, the components 3 on the substrate are well protected, and more circuit devices can be added on the substrate because only the welding wire area is heated and the heating platform is removed.)

1. A micro-display wire bonding method is provided, a PCB board has an area needing wire bonding, and the method is characterized in that: preparing a hot air pipe capable of blowing hot air, aligning an air outlet of the hot air pipe with the area of the welding line, continuously heating the area of the welding line by using the hot air until the area of the welding line is heated to the required temperature, and welding two ends of the welding line in the area of the welding line.

2. The method for bonding wires for microdisplay of claim 1, wherein: the temperature of hot air blown out by the hot air pipe is 150 ℃ to 160 ℃, and the required temperature for heating the welding line area is 100 ℃ to 120 ℃.

3. The micro-display wire bonding method according to claim 2, wherein: the air volume of the hot air pipe blowing out hot air is 10-30L/min.

4. The micro-display wire bonding method according to claim 3, wherein: and when the hot air pipe is used for heating the welding line area, the distance between the air outlet of the hot air pipe and the welding line area is 5cm to 6 cm.

5. The micro-display wire bonding method according to claim 4, wherein: and when the hot air pipe is used for heating the welding line area, the duration is 3-5 s.

6. A wire bonding apparatus for the wire bonding method of micro display devices as claimed in any one of claims 1 to 5, wherein: the equipment is provided with a heat source, wherein an air blower is arranged in the heat source and used for conveying hot air to an air inlet of a hot air pipe through a pipeline, and the hot air pipe is fixed on a robot arm.

7. The wire bonding apparatus of claim 6, wherein: the heat source is a thermal oven, and the temperature in the thermal oven can at least reach 300 ℃.

8. The wire bonding apparatus according to claim 6 or 7, characterized in that: the blowing air quantity of the blower is 10-30L/min.

Technical Field

The invention relates to the field of semiconductor and LED packaging test, in particular to a Wire bonding method for Wire Bond bonding.

Background

Wire Bonding technology and function are the wiring of the circuit, so that the wafer and the packaging substrate or the lead frame complete the wiring of the circuit to play the function of electronic signal transmission. The method mainly comprises three welding principles, namely 1 hot pressure welding, 2 ultrasonic welding and 3 thermosonic welding, wherein the thermosonic welding is widely applied to semiconductors, and mainly comprises the steps of simultaneously heating and applying ultrasonic waves to a gold wire and a pressure welding point, generating plastic deformation on a contact surface, breaking an oxide film on an interface, activating the oxide film, and fully connecting the gold wire and the pressure welding point through mutual diffusion between two metals on the contact surface.

The welding principle is as follows:

1. thermocompression bonding	300-500℃	Without ultrasound	High pressure	Leading wires: au coating
					2. Ultrasonic welding	At room temperature	With ultrasound	Low pressure	Leading wires: AI, Au
3. Thermosonic welding	100-150℃	With ultrasound	Low pressure	Leading wires: au coating

Wherein the thermal pressure welding and the thermosonic welding can not heat the components to achieve the welding condition. The heating means is usually a heating panel directly heating the bottom of the wire element to reach the wire bonding condition. Generally, the higher the heating temperature, the higher the ball thrust after bonding (generally greater than 25g) and the higher the tensile force of the gold wire (generally greater than 5g) as shown in FIG. 3.

It is obvious that direct heating of the bottom of the PCB does not allow components to be present or requires avoidance of PCB bottom components (which need to be temperature resistant).

With the development of semiconductors and LEDs, the bottom of the PCB is often accompanied by some components or connectors and the temperature resistance is not up to the bonding conditions, so new bonding methods are needed.

Disclosure of Invention

The invention aims to solve the technical problem of realizing a welding method capable of reducing the heating difficulty of a PCB during welding wires.

In order to achieve the purpose, the invention adopts the technical scheme that: a method for micro-display of welding lines includes arranging an area needing welding lines on a PCB, preparing a hot air pipe capable of blowing out hot air, aligning an air outlet of the hot air pipe to the area of the welding lines, continuously heating the area of the welding lines by utilizing the hot air until the area of the welding lines is heated to required temperature, and welding two ends of the welding lines to the area of the welding lines.

The temperature of hot air blown out by the hot air pipe is 150 ℃ to 160 ℃, and the required temperature for heating the welding line area is 100 ℃ to 120 ℃.

The air volume of the hot air pipe blowing out hot air is 10-30L/min.

And when the hot air pipe is used for heating the welding line area, the distance between the air outlet of the hot air pipe and the welding line area is 5cm to 6 cm.

And when the hot air pipe is used for heating the welding line area, the duration time is 3-5 s.

A wire bonding device for the micro-display wire bonding method is characterized in that: the equipment is provided with a heat source, wherein an air blower is arranged in the heat source and used for conveying hot air to an air inlet of a hot air pipe through a pipeline, and the hot air pipe is fixed on a robot arm.

The heat source is a hot oven, and the temperature in the hot oven can reach at least 500 ℃.

The blowing air quantity of the blower is 10-30L/min.

The invention has the advantages that:

1. only the position of the welding wire is heated, and some components which cannot resist temperature are effectively avoided;

2. the electrical components are arranged on the back of the PCB, back heating and a heating platform are not needed, and the components on the substrate are well protected

3. Because only the bond wire area is heated and the heated platen is removed, more circuit devices can be added to the substrate.

Drawings

The following is a brief description of the contents of each figure in the description of the present invention:

FIG. 1 is a schematic view of a wire heating process;

FIG. 2 is a schematic view of the welding line of the ceramic nozzle after heating to a predetermined temperature;

fig. 3 is a schematic view of background art thermocompression bonding and thermosonic bonding.

Detailed Description

The following description of the embodiments with reference to the drawings is provided to describe the embodiments of the present invention, and the embodiments of the present invention, such as the shapes and configurations of the components, the mutual positions and connection relationships of the components, the functions and working principles of the components, the manufacturing processes and the operation and use methods, etc., will be further described in detail to help those skilled in the art to more completely, accurately and deeply understand the inventive concept and technical solutions of the present invention.

The common heating methods include panel heating and hot air heating. Then, the bonding wire area is heated to the condition required by bonding wires by a hot air heating mode, so that some electric components or panels which are sensitive to temperature are avoided from being heated in an unheated area.

An adjustable and controllable heat oven is prepared, an air supply mechanism, preferably an air blower, is fixed in the heat oven, the air blower can adjust the air quantity to 10L/min-30L/min, and the room temperature of the heat oven can reach 500 ℃.

Hot air of the hot oven is conducted to the air outlet of the hot air pipe through the hot air pipe, the hot air pipe nozzle is fixed with the robot arm, and the hot air pipe nozzle is brought into the welding line area through the robot arm.

During welding, hot air is brought into a welding line area through an air outlet of the hot air pipe;

and controlling the distance from a nozzle of the hot air pipe to a welding line to be about 5cm to 6cm, the time to be 3-5s, the air quantity to be 20L/min and the hot air temperature to be 150-160 ℃ to heat the welding line area to be 100-120 ℃.

And heating the welding wire area to the required temperature, stopping the heat drying oven, bringing the arm of the instrument to the heat return air pipe, and welding the welding wire at the position of the required welding wire in the heating area.

The invention has been described above with reference to the accompanying drawings, it is obvious that the invention is not limited to the specific implementation in the above-described manner, and it is within the scope of the invention to apply the inventive concept and solution to other applications without substantial modification.