Environmental Engineering Reference
In-Depth Information
-3
(a)
(a)
n = 1 . 6 8
φ
= 1 . 1 4
-4
-5
-6
-7
-8
-9
-10
0.0 0.2 0.4 0.6 0.8 1.0
Voltage (V)
Figure 3.10
Typical log-linear I-V characteristics under dark conditions
for an n-n-i-p structure shown in Fig. 3.9 and fabricated with electrode-
posited layers. Note the RF of
∼
10
6
,the
n
of 1.68, and the potential barrier
height (
φ
b
)of1.14eV[17].
Figure 3.10 shows a dark I-V curve of a four-layer device
fabricated using electrodeposition with an n-n-i-p structure, as
shown by the energy band diagram in Fig. 3.9. This is an excellent
diode with the rectification factor (RF) at 1.00 V, about six orders
of magnitude, ideality factor (
n
) of 1.68, and a potential barrier
of 1.14 eV. The future work should be directed towards research
and development of these promising multi-layer graded bandgap
solar cell structures using low-cost electrodeposited materials.
The challenges faced by researchers are the consistency and
reproducibility of materials growth due to the existence of four
or five different elements in this alloy compound semiconductor.
