LED environmental resistance

LED environmental resistance

LEDs are made up of a combination of different materials.
Therefore, depending on the environment in which it is used, the material may be affected by the external environment.
Here, we will explain sulfurization as an example.

LEDs sometimes use silver in the lead FRAMES to increase the efficiency of light extraction from the chip.
Therefore, if sulfur compounds get inside the LED, they can react chemically with silver, causing it to blacken.
Blackening can cause the LED to lose brightness, change color, or become open.

There are two main approaches to improving the sulfur resistance of LEDs:

1. How to prevent sulfur compounds from entering
One method of preventing sulfur compounds from penetrating into the LED is to use epoxy resin as the encapsulating resin.
Epoxy resin has a high sealing property and can effectively prevent the intrusion of sulfur compounds from the outside.

2. Using materials that do not react with sulfur compounds
The effects of sulfuration can be prevented by using materials that do not react chemically with sulfur compounds.
For example, by using a material with high sulfide resistance, such as gold, it is possible to suppress deterioration due to sulfide.

These mechanisms allow LED manufacturers to improve the sulfur resistance of LEDs and increase their reliability.

The following methods are effective in protecting LEDs from sulfur compounds:

1. Use materials that do not contain sulfur compounds
For example,

• rubber
• Substrate resist
• exhaust gas
• hot spring water

Avoiding materials containing these sulfur compounds and using materials that do not contain sulfur compounds can prevent sulfuration in LEDs. It is particularly important to carefully select the product's usage environment and surrounding materials.

2. Use LEDs with high sulfur resistance
In environments where sulfur compounds cannot be completely eliminated, it is effective to use LEDs with high sulfur resistance.
For example, the effects of sulfurization can be reduced by using epoxy resin as the encapsulant or by selecting LEDs that are designed without silver.

Combining these methods can protect LEDs from sulfuration and maintain stable performance over the long term.