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 the dislocation densities are set
to 1.2 × 108 , 2.4 × 108 , and 5 ×
108 cm−2 for LED structures
with 1.5, 2.0, and 2.5 nm well
thicknesses
 The Auger coefficient is set to
1.8 × 1030 𝑐𝑚6 /s for active
regions of all three structures
 It is believed that LED
samples with thicker well
structures lead to more
dislocation density induced by
more internal strain effect
Fig. 3. Simulation results of IQE at different current densities.
𝐽𝑟𝑎𝑑
𝐼𝑄𝐸 =
𝐽𝑡𝑜𝑡𝑎𝑙
 The simulation results match
the experimental results very
well.
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Fig. 4. Ratios of dislocation recombination rates to total carrier recombination rates,
Rdis/Rdis + Rrad + RAuger , and Auger recombination rates to total carrier recombination
rates, RAuger/Rdis + Rrad + RAuger, versus total current density. The ratios of dislocation
recombination rates are higher than that of Auger recombination rates at low current
densities. As current densities increase, ratios of dislocation recombination rates decrease
and ratios of Auger recombination rates increase.
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Fig. 5. Ratios of nonradiative current densities to total current densities Jnrad /Jtotal and
carrier overflow current densities to total current densities Joverflow /Jtotal at different
current densities. Jnrad /Jtotal saturates at current higher than 100 A/cm2 . Joverflow
/Jtotal increases as total current densities increase.
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TABLE I
VARIATIONS OF IQE, RATIO OF NONRADIATIVE CURRENT DENSITIES TO
TOTAL CURRENT DENSITIES (JNRAD /JTOTAL ) AND RATIO OF CARRIER
OVERFLOW CURRENT DENSITIES TO TOTAL CURRENT DENSITIES
(JOVERFLOW /JTOTAL ) IN DIFFERENT CURRENT DENSITY RANGES
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