Chip antistatic ability
With the increasing competition in the LED industry, LED quality has received unprecedented attention. During the manufacture, transportation, assembly and use of LEDs, production equipment, materials and operators are likely to cause electrostatic (ESD) damage to the LEDs, leading to premature LED leakage current increase, light attenuation, and even dead lights.
Phenomenon, static electricity has a very important impact on LED quality. The antistatic index of LED is not only simply reflecting its antistatic strength. The antistatic ability of LED has a great relationship with its leakage value and overall reliability, and it is a comprehensive reflection of overall quality and reliability. Because it is often anti-static high LED, its light characteristics, electrical characteristics will be good.
LED electrostatic failure principle:
Due to the different levels of static electricity in the environment, a certain amount of electrostatic charges having opposite polarities are accumulated at both ends of the PN junction of the LED chip by electrostatic induction or direct transfer to form different degrees of electrostatic voltage. When the electrostatic voltage exceeds the maximum withstand value of the LED, the electrostatic charge will discharge between the two electrodes of the LED chip in a very short time (nanoseconds), thereby generating heat. The conductive layer inside the LED chip and the PN junction light-emitting layer form a high temperature of 1400 ° C or higher, and the high temperature causes partial melting into small holes, thereby causing LED leakage, darkening, dead light, short circuit, etc.
LEDs that are damaged by static electricity often cause dead lights and electric leakage. Slight electrostatic damage, LED generally has no abnormalities, but at this time, the LED has a certain hidden danger, when it is subject to secondary electrostatic damage, then there will be a chance of dark, dead lights, leakage. Based on the data experience summarized by Jinjian Lab's case analysis for many years, when the LED chip is subjected to slight, undetected electrostatic damage, it is necessary to scan the electron microscope to enlarge it to more than 10,000 times to further confirm the diagnosis to prevent the higher probability of failure accident.
Antistatic index depends on LED chip, but LED lamp is more susceptible to electrostatic damage
The anti-static index of the LED lamp bead depends on the LED light-emitting chip itself, which is basically independent of the encapsulation material's expected packaging process, or the influence factor is small and very subtle; the LED lamp is more susceptible to electrostatic damage, which is separated from the two pins.
Relationship, the distance between the two electrodes of the bare chip of the LED chip is very small, generally less than one hundred micrometers, and the LED pin is about two millimeters. When the electrostatic charge is to be transferred, the larger the spacing, the easier it is to form a large potential difference. , that is, high voltage. Therefore, it is often more prone to electrostatic damage accidents after being sealed into LED lights.
Good antistatic index is a comprehensive reflection of the comprehensive performance of LED
The antistatic index of LED is not only simply reflecting its antistatic strength. Anyone who knows the design and manufacture of LED chips knows that the antistatic ability of LED chips has a lot to do with its leakage value and overall reliability. A comprehensive performance of comprehensive quality and reliability, because LEDs with high antistatic ability, its optical characteristics and electrical characteristics will be good.
The antistatic index of LEDs not only means that it can be applied to various products and various environments, but also the reliable performance of LED comprehensive performance. According to the actual anti-static index of LEDs of different brands measured by Jinjian, the anti-static of LEDs of various international LED manufacturers is generally better, while the anti-static of some B products, miscellaneous brands and Korean chips are still very low. The antistatic ability of LED is the core embodiment of LED reliability. Even if the brightness and electrical properties of the LED are good, once the antistatic index is low, it is easy to die due to electrostatic damage. Testing the antistatic index of LED is a very effective quality control method, and it is urgent to evaluate the antistatic ability of LED effectively.