The optical and thermal properties of the CSP LEDs were investigated as function of the phosphor film thickness and width. Eight different types of phosphor-converted white CSP LEDs were prepared by using mixed multicolor phosphors. It was shown that with increasing phosphor film thickness, the luminous flux and the radiation angle increased. On the other hand, as the CSP area increased, the radiation angle decreased. This behavior was attributed to the fact that the blue light of the LED did not excite the whole area of the phosphor. At high current, the junction temperature increased with increasing phosphor film thickness and the thickest phosphor sample showed the highest junction temperature. The results demonstrate a simple method of optimizing the phosphor layer thickness and width for the fabrication of high-performance white LEDs for a white light source.
|Title of host publication
|J. Hite, V. Chakrapani, J. Zavada, T. J. Anderson, S. Kilgore
|Electrochemical Society Inc.
|Number of pages
|Published - 2018
|Symposium on Wide Bandgap Semiconductor Materials and Devices 19 - 233rd ECS Meeting - Seattle, United States
Duration: 2018 May 13 → 2018 May 17
|Symposium on Wide Bandgap Semiconductor Materials and Devices 19 - 233rd ECS Meeting
|18/5/13 → 18/5/17
Bibliographical noteFunding Information:
This work was supported by LG Innotek Co., Ltd. and the Global Research Laboratory (GRL) program through the National Research Foundation of Korea (NRF) funded by the Ministry of Science, ICT, and Future Planning (NRF-2017K1A1A2013160).
ASJC Scopus subject areas
- General Engineering