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P. 246
Chapter 8
between J (IV) and J (EQE) as obtained at t=0 h. The mismatch between the Jsc from
sc
sc
IV and the EQE measurements was between 15.8 and 16.9%. After degradation, the
mismatch was between 15.6 and 17.0% for the non-degraded and the HO/O , H O/
2
2
2
N and unpurged H O samples. EQE on H O/CO /N and H O/air samples did not show
2
2
2
2
2
2
any current, while the IV reported very low currents.
A Leica Wild M400 macroscope and a digital camera were used to determine the visual
changes. Lock-in thermography (LIT) images were taken using an ImageIR camera and
a Sunfilm IR lens from Infratec.
The morphological and structural properties of the layers were determined by a FEI
XL40 FEG Scanning Electron Microscope (SEM). Compositional depth profiles were
performed by SIMS using a magnetic sector Cameca IMS 7F instrument in the positive
mode with Cs ions, the primary beam intensity was 57nA with 5keV acceleration and
+
it was rastered by 200x200 μm .
2
8.3 Results
8.3.1 Structural properties
Figure 8.3 shows microscopy pictures of the surface of the samples before (a) and
after 340 hours exposure to the different conditions (b-f). It is shown that all samples
looked less homogeneous after exposure, which can be observed as surface patterns.
The effect is the largest for the HO/air and H O/CO /N samples, while the latter also
2
2
2
2
has a slightly purple red colour after exposure.
Figure 8.3 Figure 3: Microscopy photos taken on the (a) H 2O/O 2 sample
Figure 3: Microscopy photos taken on the (a) H 2O/O 2 sample
Microscopy photos taken on the surface of the (a) H 2 O/O 2 sample before degradation (b-f) after 340 hours exposure to (b)
before degradation (b-f) after 340 hours exposure to (b) H 2O
before degradation (b-f) after 340 hours exposure to (b) H 2O
(c) H 2O/N 2 (d) H 2O/O 2 (e) H 2O/air (f) H 2O/CO 2/N 2
H 2 O (c) H 2 O/N 2 (d) H 2 O/O 2 (e) H 2 O/air (f) H 2 O/CO 2 /N 2
(c) H 2O/N 2 (d) H 2O/O 2 (e) H 2O/air (f) H 2O/CO 2/N 2
244
between J (IV) and J (EQE) as obtained at t=0 h. The mismatch between the Jsc from
sc
sc
IV and the EQE measurements was between 15.8 and 16.9%. After degradation, the
mismatch was between 15.6 and 17.0% for the non-degraded and the HO/O , H O/
2
2
2
N and unpurged H O samples. EQE on H O/CO /N and H O/air samples did not show
2
2
2
2
2
2
any current, while the IV reported very low currents.
A Leica Wild M400 macroscope and a digital camera were used to determine the visual
changes. Lock-in thermography (LIT) images were taken using an ImageIR camera and
a Sunfilm IR lens from Infratec.
The morphological and structural properties of the layers were determined by a FEI
XL40 FEG Scanning Electron Microscope (SEM). Compositional depth profiles were
performed by SIMS using a magnetic sector Cameca IMS 7F instrument in the positive
mode with Cs ions, the primary beam intensity was 57nA with 5keV acceleration and
+
it was rastered by 200x200 μm .
2
8.3 Results
8.3.1 Structural properties
Figure 8.3 shows microscopy pictures of the surface of the samples before (a) and
after 340 hours exposure to the different conditions (b-f). It is shown that all samples
looked less homogeneous after exposure, which can be observed as surface patterns.
The effect is the largest for the HO/air and H O/CO /N samples, while the latter also
2
2
2
2
has a slightly purple red colour after exposure.
Figure 8.3 Figure 3: Microscopy photos taken on the (a) H 2O/O 2 sample
Figure 3: Microscopy photos taken on the (a) H 2O/O 2 sample
Microscopy photos taken on the surface of the (a) H 2 O/O 2 sample before degradation (b-f) after 340 hours exposure to (b)
before degradation (b-f) after 340 hours exposure to (b) H 2O
before degradation (b-f) after 340 hours exposure to (b) H 2O
(c) H 2O/N 2 (d) H 2O/O 2 (e) H 2O/air (f) H 2O/CO 2/N 2
H 2 O (c) H 2 O/N 2 (d) H 2 O/O 2 (e) H 2 O/air (f) H 2 O/CO 2 /N 2
(c) H 2O/N 2 (d) H 2O/O 2 (e) H 2O/air (f) H 2O/CO 2/N 2
244
