具有線柵薄膜偏光片(Wire grid polarizer film, WGF)的白光晶片直
接封裝(Chip-on-board, COB)發光二極體(Light emitting Diodes, LED)，
有偏極化光源、高消光比、降低眩光及提升顏色均勻性等優點。隨著
白光 COB LED 功率的增加，使得白光 COB LED 封裝膠的表面溫度
跟著提高。因此無法使用基板材質為塑膠的線柵薄膜偏光片。
為了降低高功率白光 COB LED 的表面溫度，本研究針對白光
COB LED 的封裝結構、散熱器與散熱膏做優化。白光 COB LED 的
最佳封裝結構為玻璃板/螢光膠層/藍光 COB LED。實驗的結果顯示，
螢光膠層添加氧化鋁粉的最佳封裝結構白光 COB LED 與傳統白光
COB LED 相比，其表面溫度下降 9.5%且出光量下降 9.7%。其中蓋在
螢光膠層上之玻璃板作用可以降低溫度與增加出光量，而在螢光膠層
內添加氮化鋁粉可提升導熱係數。對於散熱器而言，表面面積大的柱
型散熱鰭片散熱器具有較佳的散熱效果。對於散熱膏而言，混合有石
墨烯與碳漿之散熱膏在適當的濃度與厚度下具有最佳散熱性。

The high power polarized white chip-on-board (COB) type light
emitting diodes (LEDs) which packaged with the wire-grid polarizer film
(WGF) have a characteristics of polarized light, high extinction ratio,
reduced glare and improved angular illumination uniformity. As the output
power of white COB LED increases, the surface temperature of the
phosphor resin layer of the white COB LED rise. Therefore, the wire-grid
polarizer with polymeric substrate cannot be implemented into the white
COB LEDs.
To lower the surface temperature of phosphor resin layer on the high
power white COB LED, we investigated the optimized package structures
of white COB LED, heat sink and thermal grease in this study. The
optimized package structure is as Glass substrate /Phosphor resin mixed
with Aluminum Nitride (AlN) /blue COB LED. According to the
experimental results, the white COB LED with the optimized package
structure which has the phosphor resin blending with AIN powder reduce
the surface temperature by 9.5% and the luminous efficiency by 9.7%
while compared with the traditional white COB LED. The effect of the
glass substrate, which is deposited on the top of the silicon resin, is to
reduce the surface temperature and enhance the output luminance. The
AIN particulate can improve the thermal conductivity of the phosphor resin
layer when add to the silicon resin. For the heat sink, the larger of surface
area of the heat dissipation fin of the column type heat sink, the better heat
dissipation effect. For the thermal grease made of mixing carbon paste with
graphene powder, an appropriate concentration and thickness have best
thermal performance.

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