LED has the advantages of small size, low power consumption, long life and environmental protection, etc. In the actual production and development process, it is necessary to evaluate the reliability level of LED chip through life test, and improve the reliability level of LED chip through quality feedback, so as to ensure the quality of LED chip.

Determination of life test conditions

Electronic products in the specified working and environmental conditions, the work of the test is called life test, also known as durability test.
With the improvement of LED production technology level, the life and reliability of the product improved, LED the theory of life of 100000 hours, if still adopts the conventional life test under normal stress rating, it is very hard to the life and reliability of the product to make relatively objective evaluation, and the main purpose of our experiment is to, through the life test master LED chip light output attenuation situation, thus infer that its life.
According to the characteristics of LED devices, through comparative tests and statistical analysis, the life test conditions of chips below 0.3× ~ 0.3mm2 are finally specified:
Random samples, the number is 8 ~ 10 chip, made ф 5 single lamp;
The working current is 30mA;
The environmental conditions were at room temperature (25℃±5℃).
The experiment period was 96 hours, 1000 hours and 5000 hours.
The working current of 30mA is 1.5 times of the rated value, which is the life test of increasing the electrical stress. Although the results cannot represent the real life condition, they are of great reference value. Life test for epitaxial wafer production batch of mother sample, a random sample of a piece of 8 ~ 10 particles in the epitaxial wafer chip, encapsulated into a ф 5 single lamp device, life test for 96 hours, the results on behalf of all the extension of the production batch.
Generally speaking, the test cycle of 1000 hours or more is called long life test. When the production process is stable, the frequency of 1000-hour life test is lower, and the frequency of 5000-hour life test is lower.