LI Shu-ti, FAN Guang-han, ZHOU Tian-ming, SUN Hui-qing, WANG Hao, ZHENG Shu-wen, GUO Zhi-you. Influence of Thermal Annealing to the Characteristics of AlGaInP/GaInP Multiple Quantum Wells LED Wafers[J]. Chinese Journal of Luminescence, 2004,(5): 510-514
LI Shu-ti, FAN Guang-han, ZHOU Tian-ming, SUN Hui-qing, WANG Hao, ZHENG Shu-wen, GUO Zhi-you. Influence of Thermal Annealing to the Characteristics of AlGaInP/GaInP Multiple Quantum Wells LED Wafers[J]. Chinese Journal of Luminescence, 2004,(5): 510-514DOI:
The AlGaInP/GaInP multiple quantum wells red LED wafers were grown by EMCORE GS/3200 LP-MOCVD.Properties of these wafers were investigated by ECV and photoluminescence measurements.The influences of thermal annealing on the characteristics of AlGaInP/GaInP multiple quantum wells LED wafers were studied. The AlGaInP/GaInP multiple quantum wells LED wafer for thermal annealing experiments consisted of a 0.5 μm n-GaAs buffer layer with carrier concentration of about 5×10
17
cm
-3
a 0.5 μm n-(Al
0.7
Ga
0.3
)
0.5
In
0.5
P cladding layer with carrier concentration of about 3×10
17
cm
-3
a (Al
0.3
Ga
0.7
)
0.5
In
0.5
P/Ga
0.5
In
0.5
P MQW active region
a 0.5 μm p-(Al
0.7
Ga
0.3
)
0.5
In
0.5
P cladding layer with carrier concentration of about 6×10
17
cm
-3
and a 4.8 μm p-GaP current spreading layer with carrier concentration of about 5×10
18
cm
-3
.The wafer was split into six pieces.These six pieces were annealed under different temperatures within 460~780℃ respectively for 15 min in nitrogen.Compared with as grown samples
the hole carrier concentration of GaP layer in LED wafer increased from 5.6×10
18
cm
-3
to 6.5×10
18
cm
-3
and the hole carrier concentration of AlGaInP layer increased from 6.0×10
17
cm
-3
to 1.1×10
18
cm
-3
when wafer was annealed under 460℃ for 15 min in nitrogen.The hole carrier concentration of GaP and AlGaInP layers did not obviously change when the annealed temperature was increased to 700℃.However
the hole carrier concentration of GaP layer and AlGaInP layer decreased to 8×10
17
cm
-3
and 1.7×10
17
cm
-3
when wafer was annealed under 780℃ for 15 min.And the diffusibility of Mg atoms was enhanced and the undoped AlGaInP/GaInP MQW was p type conductance when the annealing temperature increased to 780℃.The peak wavelength and FWHM did not obviously change when the annealing temperature was lower than 780℃.However
the PL peak intensity from MQW was about 2 times stronger than that of as grown sample when wafer was annealed under 780℃ for 15 min.