LED the improvement measure failure problem

LED the improvement measure failure problem

Discovery
Through the above-mentioned LED the main failure mode analysis, which LED light in actual use that improve the service life of the technology.

(1) thermal technology

Cooling technology has been LED the important link of the application effect, if not in time to heat LED devices, will lead to the junction temperature rise serious chip, then the luminous efficiency fell sharply and reliability (such as life, color shift etc) will deteriorate; At the same time, high temperature high fever will make LED encapsulation structure internal produce mechanical stress, may be further cause a series of reliability problem [5]. Therefore, in the manufacturing process, can choose good thermal conductivity of the base, and that LED's heat area as far as possible big, thus increasing the heat dissipating performance of the device.

(2) anti-static technology

In the first section 2.4, as already mentioned in GaN chip, in use existing LED a very big problem is, if not the electrostatic effect deal with this, it will be seriously affected the life span of the device. Therefore, in LED the design, full consideration should be given to the design of anti-static, in order to avoid devices because high the electrostatic voltage cause breakdown and failure phenomenon.

(3) packaging technology

Encapsulation of epoxy resin material used for illumination and temperature rise and cause its light through rate of degradation, in use is behaved for originally transparent epoxy resin material happen Browning, affect device originally spectrum power distribution. Therefore, in the packaging, we LED to strictly control the curing temperature, to avoid the encapsulate, it has caused the epoxy resin early ageing.

On the other hand, in order to prevent corrosion phenomena in device happen choose transparency good packaging materials at the same time, should pay attention to in the process of plastic injection, try to row material interior clean air bubbles, to minimize the residues of moisture, reduce the rate of corrosion occurred device.

(4) to optimize manufacturing process

LED manufacturing process needs the right bonding conditions, if the bonding over general will be crushed chip, otherwise, will cause the bonding strength device, making the devices easy to lack off loose. Therefore, in the guarantee bonding strength of the device at the same time, need to try to reduce the bonding process of chip of the damage, in order to achieve the purpose of the bonding process optimization.

In the chip adhesive, control temperature and time requirements in the appropriate range, making the solder, no empty to dense, small residual stress the technological requirements. (5) the reasonable selection

In before they leave the factory, can increase LED a screening process, is to some of these samples of reasonable aging and screening tests, eliminate some possible failure in advance of the device, in order to reduce the actual use in LED early failure phenomenon.

conclusion

To sum up, although LED has the very high theory, but in actual life in use process, the chip, sealing, stress the influence of factors, use the time far not achieve expected the theoretical value. In order to really improve the life of LED, whether in the manufacturing process, or in the application layer surface, all need further research, exploration and practice. With LED the development of technology, will surely there will also be new problems continue to emerge. But as long as to be the root cause of the failure LED can in the practice does, indeed, improve the performance of the device, LED the new light source to the front of the promotion application field, better service to production and life.

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