Solution to LED Solid Crystal Adhesive Cracking

Single electrode chips have very high requirements for solidification in the packaging industry. For example, in the LED production process, the quality of solidification affects the quality of LED products. There are many factors that can cause LED chip breakage, and we will only explore solutions for LED chip breakage from three aspects: materials, machines, and human factors.

The phenomenon of cracking of the chip material itself

When the chip damage is greater than 1/5 of the width of a single side chip or the damage is at an oblique angle, and each single side edge is greater than 2/5 of the chip or damaged to the aluminum pad, such chips are not acceptable (this is a special item in the chip inspection standard). The main reasons for the occurrence of adverse phenomena are: 1. Improper operation by chip manufacturers; 2. Chip incoming inspection did not spot check 3, and was not picked out during online operations

Solution: 1. Notify chip manufacturers to make improvements; 2. Strengthen incoming inspection and reject chips with excessive damage ratio; 3. During the Q inspection of online homework, damaged chips should be picked out and replaced with good ones.

Improper use of LED solidification machine

1. Improper suction parameters of the machine. The suction nozzle height and solidification height of the machine are directly controlled by the parameters in the machine's computer. Large parameters, small absorption height; The parameter is small, but the suction height is large, and the damage of the chip is directly affected by the suction height parameter of the machine. The main reasons for the occurrence of adverse phenomena are: large machine parameters, low clamping height, excessive force on the chip, resulting in chip damage.

Solution: Adjust the machine parameters, increase the alert nozzle height or solidification height appropriately, adjust the nozzle height in the first item "Pick Level" of the "Bond head menu" in the "SETUP" mode of the machine, and then adjust the solidification height in the second item "Bond Level".

2. The size of the suction nozzle does not match. Chips of different sizes require different suction nozzles for solidification. Large chips require small suction nozzles, and chips that cannot be sucked up are prone to leakage and fixation; A small chip can be easily broken with a large nozzle, so choosing an appropriate nozzle is a prerequisite for fixing the chip. The reason for the adverse phenomenon is that the suction nozzle is too large, which breaks the chip.

Solution: Choose the appropriate ceramic nozzle.

Three people caused the rupture due to improper operation

1. Improper homework: Failure to operate according to regulations resulted in chip breakage. The main reasons for the occurrence of adverse phenomena are: materials not being properly handled and falling to the ground; Encountering chips when entering the oven

Solution: When holding materials, hold them firmly with your hands. When entering the oven, the material should be placed flat and gently, without tilting or applying excessive force.

2. Heavy object compression injury: The chip is broken due to excessive external force. The main reasons for this adverse phenomenon are: the microscope falls onto the material, causing the chip to break; Machine parts falling onto materials; Iron plate pressed onto the material

Solution: The microscope screws should be tightened; Regularly inspect the machine parts for looseness; There should be no iron plates or other objects passing through the material.