LED packaging technology, the basic requirements

LED packaging technology has three elements: packaging structure design, selection of appropriate packaging materials and process level, the current structure of the LED package has more than 100 kinds, the main package types are more than 40 kinds of Lamp series, SMD (chip LED and TOP LED) series More than 30 kinds, COB series of more than 30 kinds of PLCC, high-power packaging, optical integrated packaging and modular packaging, packaging technology to closely follow and meet the LED application product development needs.

LED packaging technology, the basic requirements are: to improve the light efficiency, high light color performance and device reliability.

(1)To improve the light efficiency

LED package out of the light efficiency of up to 80 to 90%.

① choose a better transparency of the packaging material: transparency ≥ 95% (1mm thickness), refractive index greater than 1.5 and so on.

② selection of high excitation efficiency, high-dominance of the phosphor, particle size appropriate.

③ mounted substrate (reflective cup) to have high reflectivity, high luminous rate of the optical design shape.

④ choose the appropriate packaging process, especially the coating process.

(2) high light color performance

LED light color of the main technical parameters: height, glare, color temperature, color, color tolerance, light flashing.

Color rendering index CRI≥70 (outdoor), ≥80 (outdoor), ≥90 (art galleries, etc.)

Color tolerance ≤3 SDCM

≤ 5 SDCM (full life period)

Package to be used to achieve the combination of multiple primary colors, focusing on improving the LED spectral distribution of the amount of radiation SPD, close to the distribution of the amount of sunlight. To pay attention to the development and application of quantum dot phosphor, to achieve better light color quality.

(3) LED device reliability

LED reliability includes LED device performance under various conditions and a variety of failure mode mechanism (LED packaging material degradation, the impact of integrated stress, etc.), which is mainly referred to the reliability of the characterization of the value of life, the current LED device life is generally 3 to 5 hours, up to 5 to 10 million hours.

① use the appropriate packaging materials: bonding strength should be large, small stress, good match, air tightness, temperature, moisture (low water absorption), anti-UV and so on.

② package heat dissipation material: high thermal conductivity and high conductivity of the substrate, high thermal conductivity, high conductivity and high strength of the solid crystal material, the stress should be small.

③ the appropriate packaging process: loading, pressure welding, packaging and other combination of strong, the stress should be small, combined to match.