Development process of phosphor coating with screen printing for white LED packaging

Author

Yu, Shan ; Yang, Liang ; Bin, Cao ; Zheng, Huai ; Chen, Mingxiang ; Liu, Sheng

Author_Institution

Sch. of Mech. Sci. & Eng., Huazhong Univ. of Sci. & Technol., Wuhan, China

fYear

2011

fDate

8-11 Aug. 2011

Firstpage

1

Lastpage

5

Abstract

An improved screen printing technology for the coating of a cerium-doped yttrium aluminum garnet (YAG): Ce³⁺ yellow phosphor on blue light emitting diodes (LEDs) is presented. A metal plate with apertures matches with wire-bonded LED chips on a substrate. Silicone with YAG: Ce³⁺ phosphor is pushed into the apertures by a squeegee blade and then the metal plate is removed by release agent after curing. The thickness of phosphor layer is controlled by the thickness of metal mask and the phosphor concentration on luminescence emission and chromaticity are investigated. In order to obtain uniform coating and an optimized geometry of the phosphor layer on the surface of LED chip, this approach is optimized to manufacture and provide a wide range of color temperature.

Keywords

cerium; curing; lead bonding; light emitting diodes; luminescence; phosphors; yttrium compounds; YAG:Ce; blue light emitting diodes; chromaticity; curing; luminescence emission; metal plate; phosphor coating; phosphor concentration; release agent; screen printing; squeegee blade; white LED packaging; wire bonded LED chips; Coatings; Image color analysis; Light emitting diodes; Metals; Packaging; Phosphors; Printing;

fLanguage

English

Publisher

ieee

Conference_Titel

Electronic Packaging Technology and High Density Packaging (ICEPT-HDP), 2011 12th International Conference on

Conference_Location

Shanghai

Print_ISBN

978-1-4577-1770-3

Electronic_ISBN

978-1-4577-1768-0

Type

conf

DOI

10.1109/ICEPT.2011.6066799

Filename

6066799