86
V. L. Borblik
-0.6
-0.4
-0.2
0.0
0.2
0.4
0
1
2
3
4
5
6
U, V
1/ C 2
, (
pF/ cm 2
)
-2
r 0 = 100 nm
(a)
(b)
(c)
-0.6
-0.4
-0.2
0.0
0.2
0.4
0
2
4
6
8
10
12
1/ C 2
, (
pF/ cm 2
)
-2
U, V
r 0 = 70 nm
-0.6
-0.4
-0.2
0.0
0.2
0.4
0
2
4
6
8
10
12
14
16
18
U, V
1/ C 2
, (
pF/ cm 2
)
-2
r 0 = 60 nm
Fig. 5 Dependence of 1/C 2 on applied voltage in p-Ge/n-GaAs heterojunction (solid curves), in
Ge p-n homojunction (dash-dot), and in GaAs p-n homojunction (dash-dot-dot) at interface radius
of 100 nm (a), 70 nm (b), and 60 nm, (c) and the same impurity concentrations N A1 = N D2 = 10 18
cm −3
4 Nanowire Radial p-i-n Diode
4.1 Theory
Schematic view of the structure under consideration is presented in Fig. 6. Here,
i-layer is located between r 1 and r 2 .
In the depletion approximation, we have next Poisson’s equations
1
r
d
dr
(r E) =
q N A
ε S
,
r p ≤ r ≤ r 1 ,
(18a)
1
r
d
dr
(r E) = 0,
r 1 ≤ r ≤ r 2 ,
(18b)