Chemistry Reference
In-Depth Information
4K
20K
0K
50K
100K
200K
Fig. 10.6
Sample temperature dependence of EL intensities from the annealed sample
The P
+
ion implantation was carried out with the ion energy of 30 keV and a dose of
10
14
cm
−
2
followed by annealing at 500
◦
C to make n-type regions. The temperature
dependence of the EL spectra at 6mA injection current is shown in Fig.
10.7
a. EL
peaks with very broad distribution in 1.5-1
.
μ
m range are observed even at room
temperature. This is considered due to the fact that the radiative recombination pro-
cesses increase in the multilayer structures by the increase of the radiative Ge-Si-O
complex areas.
Figure
10.7
b shows injection current density
J
dependence of EL peak intensities
I
's centered at 1
7
m at several measurement temperatures. The EL intensities are
proportional to
J
m
. The exponent
m
's increase from 0.74 to 1.3 with the increase
of the measurement temperatures. This suggests that the recombination processes
are dominated by the process of Auger recombination at low temperature (7 K) and
by the recombination process at non-radiative recombination sites at room temper-
ature (300 K).
.
55
μ
(a)
Injection current density:
J
(A/cm
2
)
Fig. 10.7
EL intensities from Ge nanodot multilayer structures. (
a
) EL spectra at different sample
temperatures and (
b
) injection current dependence of EL peak intensities at 1
.
55
μ
mregionat
different sample temperatures (7, 100, 300 K)
