During manufacturing of a CIGS device, the metal back contact is deposited first, while in case of the CdTe solar cells, the back contact is deposited in the last processing step. What are the configurations of both cells:
a) Both the CI(G)S and CdTe solar cells are made in superstrate stucture.
b) The CI(G)S solar cell is made in a superstrate structure, whereas CdTe solar cell is made in a substrate structure.
c) The CI(G)S solar cell is made in a substrate structure, whereas CdTe solar cell is made in a superstrate structure. d)Both CI(G)S and CdTe solar cells are made in substrate stucture.
question?
c
c) The CI(G)S solar cell is made in a substrate structure, whereas CdTe solar cell is made in a superstrate structure.
c) The CI(G)S solar cell is made in a substrate structure, whereas the CdTe solar cell is made in a superstrate structure.
To understand why the metal back contact is deposited first in CI(G)S devices and in the last processing step in CdTe solar cells, it's important to know the difference between superstrate and substrate structures in solar cells.
In a superstrate structure, the light enters the solar cell through the top transparent electrode and exits through the back contact. This means that the sunlight has to pass through all the layers of the solar cell before reaching the back contact. In this configuration, the back contact is usually deposited in the last processing step to prevent any damage or interference with the layers above it.
On the other hand, in a substrate structure, the light enters the solar cell through the back contact and exits through the top transparent electrode. In this configuration, the back contact is deposited first because it will be in direct contact with the incoming sunlight. By depositing the back contact first, it ensures good electrical conductivity and efficient collection of the generated electricity.
Based on this information, option c) is the correct answer where the CI(G)S solar cell is made in a substrate structure and the CdTe solar cell is made in a superstrate structure.