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INTRODUCTION

Compared to InGaN-based LEDs, AlGaN LEDs may be
subject to more severe self-heating due to higher operation voltage
and lower radiative efficiency. The poor electrical conductivity of
AlGaN materials was found to exacerbate the current crowding and
localized heating problems.

In this paper, we report on the temperature-dependent
performance of state-of-the-art AlGaN-based LEDswith different Al
contents. In contrast to dominant localized stated emission in InGaN
LEDs, the UV emission is mainly caused by band-to-band transition,
and much more sensitive tothe junction temperature due to smaller
carrier-confining and localization potentials.
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STRUCTURE
Chip Size: 7.0*10-4 cm2
P
N
p+-GaN: Mg cladding
p-AlGaN: Mg cladding
AlGaN MQW
n-AlGaN:Si cladding
AlN/AlGaN Superlattice
AlN
365, 335, 280, and 265nm @10mA
Migration-enhanced MOCVD
sapphire
(Flip-Chip on PCB)
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