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EXPERIMENTAL DETAILS
FIG. 1. Color online Schematic structure InGaN/GaN multiple quantumwell
LEDs with varied well thicknesses
 veeco metal–organic
chemical vapor deposition
system
 Chip size 350*350µ𝑚2
 MQW growth time are 1.5 nm
(1 min), 2.0 nm (1.33 min),
and 2.5 nm (1.67 min),
respectively
 mounted onto TO-46 lead
frames without epoxy
encapsulation
 pulse duration 3 ms and duty
cycle 5% by Keithley 24001
source meter.
RESULTS AND DISCUSSION
2.9%
26.3%
43.8%
Fig. 1. Normalized EQE measurements of the MQW LEDs with varied
well thicknesses. A reduced efficiency droop behavior is demonstrated for
the samples with thicker quantum wells. The inset shows absolute values of
the external quantum efficiencies for the samples.
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Fig. 2. Schematic figure of total current density Jtotal = Jrad + Jnrad +Joverflow .
𝐽𝑡𝑜𝑡𝑎𝑙 = 𝐽𝑟𝑎𝑑 + 𝐽𝑛𝑟𝑎𝑑 + 𝐽𝑜𝑣𝑒𝑟𝑓𝑙𝑜𝑤 (1)
R= 𝑅𝑟𝑎𝑑 + 𝑅𝑑𝑖𝑠 + 𝑅𝐴𝑢𝑔𝑒𝑟 2
𝐽𝑛𝑟𝑎𝑑 = 𝐽𝑑𝑖𝑠 + 𝐽𝐴𝑢𝑔𝑒𝑟 (3)
 Utilizing a commercial
software—simulator of light
emitters based on nitride
semiconductors(SiLENSe)—
is performed.
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