Why blue-green light LED chips need to be fixed with insulating adhesive instead of silver adhesive

Analysis of the Reasons Why Blue-Green Light LED Chips Need to Be Fixed with Insulating Adhesive Instead of Silver Adhesive
　　I. Introduction@@@@@@@@@@@@@@@@@@@@@@

LED technology is one of the most important technologies of the 21st century. It not only shines in the field of lighting but also plays an important role in many other fields such as display, indication, and backlight. Among them, blue-green light LED chips have a wide range of applications in the fields of display and lighting, and their performance directly affects the quality of the product. The packaging process of blue-green light LED chips is one of the key factors that determine their performance, and the fixing method of blue-green light LED chips has an important impact on the performance of the chips. Currently, the main fixing methods for blue-green light LED chips are silver adhesive and insulating adhesive. Silver adhesive has good conductivity and can achieve a good electrical connection between the chip and the packaging substrate, but its coefficient of thermal expansion is different from that of the LED chip, which is easy to cause thermal stress on the chip, thereby affecting the performance of the chip. Insulating adhesive has good insulation properties and can effectively avoid the thermal stress problems brought by silver adhesive, therefore, the fixing method of blue-green light LED chips mostly adopts insulating adhesive. This article will analyze in depth the reasons why blue-green light LED chips need to be fixed with insulating adhesive instead of silver adhesive.

II. Influencing Factors of the Selection of Blue-Green Light LED Chip Fixing Methods

1. Thermal Stress

Blue-green light LED chips generate a large amount of heat during the working process. If the fixing method is not proper, it is easy to cause thermal stress between the chip and the packaging substrate, which affects the performance of the chip. Silver adhesive has good conductivity and can achieve a good electrical connection between the chip and the packaging substrate, but its coefficient of thermal expansion is different from that of the LED chip, which is easy to cause thermal stress on the chip, thereby affecting the performance of the chip. Insulating adhesive has good insulation properties and can effectively avoid the thermal stress problems brought by silver adhesive, therefore, the fixing method of blue-green light LED chips mostly adopts insulating adhesive.

2. Mechanical stress

During the packaging process of blue-green light LED chips, they will be affected by mechanical stress, such as mechanical stress generated during the packaging process, and mechanical stress between the packaging material and the chip. Silver glue will produce a certain amount of shrinkage during the curing process, which may cause mechanical stress to the chip, thereby affecting the performance of the chip. Insulating glue does not produce obvious shrinkage during the curing process and can effectively avoid the impact of mechanical stress on the chip.

3. Thermal resistance

During the working process, blue-green light LED chips will produce a large amount of heat. If the fixation method is not appropriate, it will lead to an increase in thermal resistance between the chip and the packaging substrate, affecting the performance of the chip. Silver glue has good conductivity, which can achieve a good electrical connection between the chip and the packaging substrate. However, its coefficient of thermal expansion is different from that of the LED chip, which is prone to cause thermal stress to the chip, thereby affecting the performance of the chip. Insulating glue has good insulation performance and can effectively avoid the thermal stress problem brought by silver glue, therefore the fixation method for blue-green light LED chips mostly uses insulating glue.

3. Optimization scheme for the selection of fixation methods for blue-green light LED chips

1. Choose appropriate insulating glue

When choosing insulating glue, factors such as thermal resistance, insulation performance, and curing speed should be considered. Choosing the appropriate insulating glue can effectively avoid the thermal stress problem brought by silver glue, thereby improving the performance of blue-green light LED chips.

2. Optimize packaging process

Optimizing the packaging process can effectively avoid thermal stress and mechanical stress between the chip and the packaging substrate, thereby improving the performance of blue-green light LED chips. For example, double-sided tape can be used for chip fixation, which avoids the thermal stress problem brought by silver glue and can effectively avoid the impact of mechanical stress on the chip.

3. Choose appropriate packaging materials

Choosing the appropriate packaging material can effectively avoid thermal stress and mechanical stress between the chip and the packaging substrate, thereby improving the performance of blue-green light LED chips. For example, high thermal conductivity packaging materials can be used to effectively reduce the thermal resistance between the chip and the packaging substrate, thereby improving the performance of the chip.

4. Conclusion

In summary, the choice of the fixation method for blue-green light LED chips has an important impact on the performance of the chips. Currently, the fixation method for blue-green light LED chips mostly uses insulating glue, while silver glue has good conductivity, which can achieve a good electrical connection between the chip and the packaging substrate. However, its coefficient of thermal expansion is different from that of the LED chip, which is prone to cause thermal stress to the chip, thereby affecting the performance of the chip. Therefore, the fixation method for blue-green light LED chips mostly uses insulating glue to avoid the thermal stress problem brought by silver glue, thereby improving the performance of blue-green light LED chips.