Epoxy resin is one of the essential materials of LED
its performance affects directly on the reliability and output effect of the products.So
in the process of manufacturing LED
the epoxy resin should be selected according to the situations
make sure the product are satisfied customers' requirements.1.The influence of epoxy resin upon the reliability of the products Use №.02
12
14(with other same material e.g.chips)to package φ3 transparent type LEDs.In half of them is used in the second bond position to fix.Carry the soldering heat-resistant trial and PCB trial on the products(store in high temperature in the condition of external force).It is proved that №.14 epoxy resin is the best choice for improving products reliability.2.The influence of epoxy resin upon the light output effect of the products Use №.02
12
14(with other same material e.g.chips)to package 5 transparent type infrared LED(each 20 pcs).Test the light power of some samples.It showed that considering the light output efficiency
we should select №.12 epoxy resin.Test the samples connecting power supply in low temperature to evaluate the output stability of the products.It is proved that those products with the worse output have the little light output diminution as time goes by.Carry on the same light output and light diminution comparison tests on visible light LEDs
we have the same conclusion.So
it can be proved that the conclusion mentioned above is correct and common.3.The light selecting performance of epoxy resin According to the spectra of three kinds of photodiode made from different epoxy resins in the tests
we found light with wavelength in the range of 700~1 000nm is easy to pass through for 18C epoxy resin and 10B epoxy resin.Obviously
this material is not suitable for manufacturing the infrared opto-devices with high requirements on light selecting performance.While the 02B epoxy resin is only sensitive to infrared light with wavelength over 800nm.Using this kind of epoxy resin as packing material
it can make the products have excellent anti-jamming ability.Use special light source to shine directly on the surface of the devices
and send a same infrared signal in the same distance
18C and 10B epoxy resin have very slow response even have no response.While 02B products keep much sensitive
very like that with infrared light shining directly.It is consistent with to the result from the spectrum of tests.To conclude
the performance of epoxy resin have important effects on the reliability
the light output of the LED and the anti-jamming ability of the opto-devices.And we should select suitable epoxy resin according to the situations.