Page 39 - Mirjam-Theelen-Degradation-of-CIGS-solar-cells
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Stability of Cu(In,Ga)Se 2 Solar Cells
E C
E F
E V 0.3 eV
Figure 2.3: CIS MoO 2 / Mo
Band bending of the energy band diagram of a CulnSe 2 solar cell at the interface towards the Mo/MoO 2 back contact.
Modified based on reference [31].
A proposal for a general degradation route of non-selenised metallic molybdenum
on soda lime glass via the formation of molybdenum oxide is shown in Figure 2.4. The
change from metallic molybdenum to oxidised molybdenum has a negative effect
on the reflectivity and later also on the conductivity, as is described in reference [18].
1 2
1 Degradation due to exposure to CIGS
temperature and humidity
Back contact: MoO 2 /MoO 3 (potentially with Na)
2 CIGS deposition: selenisation and
reduction of molybdenum oxide Back contact: MoO 2 /MoO 3 /MoSe 2 (potentially with Na)
Back contact: Molybdenum
SLG
Figure 2.4
General reaction mechanism for the degradation of metallic molybdenum and the impact on the subsequent CIGS
deposition.
37
E C
E F
E V 0.3 eV
Figure 2.3: CIS MoO 2 / Mo
Band bending of the energy band diagram of a CulnSe 2 solar cell at the interface towards the Mo/MoO 2 back contact.
Modified based on reference [31].
A proposal for a general degradation route of non-selenised metallic molybdenum
on soda lime glass via the formation of molybdenum oxide is shown in Figure 2.4. The
change from metallic molybdenum to oxidised molybdenum has a negative effect
on the reflectivity and later also on the conductivity, as is described in reference [18].
1 2
1 Degradation due to exposure to CIGS
temperature and humidity
Back contact: MoO 2 /MoO 3 (potentially with Na)
2 CIGS deposition: selenisation and
reduction of molybdenum oxide Back contact: MoO 2 /MoO 3 /MoSe 2 (potentially with Na)
Back contact: Molybdenum
SLG
Figure 2.4
General reaction mechanism for the degradation of metallic molybdenum and the impact on the subsequent CIGS
deposition.
37
