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Results and discussion(3/9)
 T 2 
Eg (T )  Eg (0 K )  

T   
侷限能力較好
Blue shift (band filling effect)
應該要 T ↑ Eg ↓ Wd ↑但是沒看到此現象
InGaN沒有受到溫度影響
Figure 7. The operating current (a) and ambient temperature (b)
dependences of the EL of InGaN green SQW structure LEDs.
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Results and discussion(4/9)
 T 2 
Eg (T )  Eg (0 K )  

T   
In含量比較少
T ↑ Eg ↓ Wd ↑
AlInGaP對溫度比較敏感
Figure 8. The operating current (a) and ambient temperature (b) dependences of
the EL of conventional AlInGaP Red LEDs (Toshiba TLRH 157P).
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Results and discussion(5/9)
 T 2 
Eg (T )  Eg (0 K )  

T   
In含量比較少
有較小的侷限能階
Figure 9. The operating current (a) and ambient temperature (b) dependences of the
EL of InGaN UV SQW structure LEDs with an emission peak wavelength of 380 nm.
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Results and discussion(6/9)
 T 2 
Eg (T )  Eg (0 K )  

T   
藉由改變In的微小變量足以影響整體
T ↑ Eg ↓ Wd ↑
Figure 10. The operating current (a) and ambient temperature (b) dependences of the
EL of InGaN UV SQW structure LEDs with an emission peak wavelength of 375 nm.
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Results and discussion(7/9)
In 含 量 越 多 使
TDs越多
UV GaN on
Sapphire 和on
ELOG LED
差了快兩個
Order
為何會最亮?
推測可能載子
侷限能力遠大
於 Dislocation
的影響
Figure 11. Relative output power of UV InGaN and
GaN LEDs as functions of forward current.
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Results and discussion(8/9)
Figure 12. The wavelength dependence of the external quantum
efficiency in the GaN-based LEDs grown on sapphire substrates.
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Results and discussion(9/9)
Figure 13. The temperature dependence of the output power of
InGaN LEDs with an emission peakwavelength of 400 nm.
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Conclusion



Indium content in the overall light modulation
efficiency and the impact on the dislocation
density.
The temperature of the LED luminous
efficiency is a popular focus of discussion.
Use ELOG to reduce the dislocation generated.
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Reference


T Mukai, S Nagahama, N Iwasa, M Senoh and T Yamada, “Nitride
light-emitting diodes,” J. Phys. : Condens. Matter 13 (2001) 7089–
7098
http://www.google.com.tw/url?sa=t&source=web&ct=res&cd=2&ve
d=0CCwQFjAB&url=http%3A%2F%2Fykuo.ncue.edu.tw%2Freport
%2F014Yellow%2520green%2520AlGaInP%2520materials.doc&ei=J5ECT
KCNBMLXcZmShLUK&usg=AFQjCNEkZO_Xe9ykfScYspOAkd
ZAxzqEgQ(黃綠光磷化鋁鎵銦 (AlGaInP) 光學特性之研究)
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