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指導教授：王聖璋 博士
學生：黃伯嘉
2016/7/16
Outline
•結果與討論
•結論
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結果與討論
EDAX composition studies indicated that the layers were nearly
stoichiometric with Sn ＝50.84 at% and S ＝49.16 at%.
The as-grown SnS layers were annealed in a sulphur atmosphere at 300°C
for 60 min in order to improve the physical properties. Fig. 1 shows the X-ray
diffraction spectrum of an annealed SnS film. It can be observed that annealing the
layers resulted in an improvement in the crystallinity of the films with the suppression
of the low intensity peaks and an increase in the {1 1 1} peak intensity. The annealed
layers had an improved gain size of 0.38 mm. The annealing was also found to
decrease the electrical resistivity to 5Ωcm and a decrease in the carrier concentration
to 0.53 X1015 cm-3.
結果與討論
The CdS films grown at 180 1C
had the wurtzite crystal structure with a
strong (0 0 2)orientation. Doping the CdS
films with indium was found to lower the
electrical resistivity of the layers. Fig. 2
shows the variation of electrical resistivity
with the indium dopant concentration. CdS
films doped with 2 at% indium showed a
minimum resistivity of 5.5X10-3 Ω cm. These
films had a carrier concentration of 2.8X1019
cm-3 with a Hall mobility of 40 cm2 V-1 s-1.
The optical Eg of the films was 2.44 eV and
the optical transmittance of the films was
>85% for photons with energies lower than
the Eg.
結果與討論
J0：飽和電流密度
A：二極體理想因子
使用二極體方程式計算在在300K以下的飽和電流密度為2.9X10-6 － 4.5X10-6
－ Acm-2 ，在較低的溫度下電流飽和密度不敏感，電流密度的影響與表面缺陷有直接
的相關，表面缺陷不夠影響了電子電洞對的產生，影響了電流密度。
在溫度>300K的溫度下電流密度從原本的4.5X10-6提高至3.4X10-4 Acm-2
In order to evaluate the solar cell
performance, the SnS/CdS junctions of 0.3 cm2
area were illuminated with a light source of
100mWcm-2. Fig. 3 shows the illuminated I–V
characteristics of a typical SnS/CdS junction.
The best cells had an open circuit voltage of
260mV, a short circuit current density of 9.6
mAcm-2, a fill factor of 0.53 and with a
conversion efficiency of 1.3%. The data
indicates that there are both shunting and series
resistance problems with these initial devices.
The calculated value of the series resistance
was approximately 23Ω.
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結果與討論
The spectral response of a
SnS/CdS device is shown in Fig. 4 that
indicates a nonuniform spectral response.
The observed quantum efficiency was
approximately 70%. The heterojunction
window effect can be observed from this
plot, indicating the occurrence of response
for wavelengths within the range defined by
the energy band gaps of CdS and SnS. The
onset of collection at long wavelengths, 940
nm, corresponds to the onset of absorption
in the SnS which has an energy band gap
(Eg) of 1.32 eV. For short wavelengths here
was a sharp drop-off of response at 500 nm.
This corresponds to the absorption edge of
the CdS, (2.44 eV).
結論
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結論
Thanks for your attention
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