GaN-InGaN Heterostructure

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GaN-InGaN Heterostructure Quantum Well

• 2005. 10. 27
• ? ? ?
• Process Design Lab.

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INTRODUCTION(1)

• ?? ?? blue LED? ??? ??? ?? ?? ???? ?? ???? ?? ???
  ??? ??.
• ?? ???? ?? ??? ???? Matsuoka? ?? ?????, ?? ????
  26.2eV ??? ??? ???? ??? ? ??.
• ?-?? ??? ???? InGaN? ??? mole fraction? ?? ???
  ??? ???(23.4eV)? ?? ??? blue LED? ????? ??? ?
  ??.

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INTRODUCTION(2)

• MOCVD? ?? InGaN ??? ?? ?? InN? ??? ?? ?? ? 500??
  ?? ???? ?????.
• GaN ?? ?? ???? InGaN ??? ???? ?? ?? ???? InGaN
  ??? ???? PL(photoluminescence measurement) ?? ?
  ???? ? ??? ?? Nakamura? ?? ????.
• ?? Si? ??? InGaN ??? Mg? ??? p-type GaN ???? blue
  emission? ??? 20? ?? ??.

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EXPERIMENTAL(1)

• InGaN ??? MOCVD?? ?? ?????.
• (0001) ??? 2?? ???? ??? 1050?? ??.
• GaN ???? ????? ?? 510?? ??? ??.
• GaN ??? ????? ?? 1020?? ??? ??.

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EXPERIMENTAL(2)

• GaN ?? ? 800?? ??? Si? ??? InGaN ??? ?????.
• Mg? ??? p-GaN ??? ????? ?? ??? 1020??? ???.
• ?? ? ?? p-GaN? ?? ?? electron-beam radiation?
  ????.

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RESULT(1)

• The peak wavelength
• 440nm.
• The FWHM of the peak emission 180meV
• Blue emission? FWHM?? ???? ????? blue GaN LED?
  ??? ?? ??.

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RESULT(2)

• The output power? 20mA?? ????? ????.
• The output power 125?
• The external quantum
• efficiency 0.22
• The homostructure GaN blue LEDs
• the output power 42?

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RESULT(3)

• homostructure GaN blue LED? ???? ? forward
  voltage? ?? ??.
• ?? LEEBI ?? ??? ???? p-type GaN?? ?? ??? ????.
• ?? Nakamura? ?? ??? ?? ??? ???? ??? ?.

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GaN/InGaN Quantum Wells(1)

• GaN? ???? ???? ?? ??? ? ???? ?? ??? InGaN? ?? ???
  Quantum Well?? active region ?? ????.
• ?? GaN? AlGaN? ?? InGaN? ???? ??? ???, p-n
  junction GaN LED? ?? ??????.
• InxGa1-xN? ??? ??? ??? mole fraction? ????? ?? ?
  ??? ?? ?? ????.

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GaN/InGaN Quantum Wells(2)

• The energy band gap of InxGa1-xN (0 lt x lt 1)
• Eg(x) (1-x)Eg(InN)
• xEg(GaN) bx(1-x)
• Eg(GaN) 3.40eV
• Eg(InN) 2.07eV
• ????? ??? ???? ??? ????? ????.

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GaN/InGaN Quantum Wells(3)

• InxGa1-xN? ?? ??? ?? ???? ??? ?? ??? ?? ???
  Yoshimoto, Matsuoka? ?? ??????.
• ?? ??? 500??? 900?? ??? ?, ???? ??? 1020cm-3??
  1018cm-3?? ??? ??? ???? ???? 10cm2/Vs??
  100cm2/Vs? ????.
• Nakamula? Mukai? GaN ??? ???? ???? ???? InxGa1-xN
  ??? ???? ???? ???.

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• The emission spectra for QWs of 10, 20, 30, 50Å
• The peak wavelength of emission and the line
  width as a function of well thickness

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• ?????