Non-destructive chemical and physical characterization mechanism will allow the development of a microscopic material degradation –physical parameter- device failure relationship. Nondestructive analyses allow the samples to be characterized by several means without destroying the device. This is an advantage in some cases, since the same OPV can be characterized by different and complementary analytical methods.
1. Comparison of the qualitative and quantitative device degradation of samples that are aged in parallel at different groups. If no standard for data exchange exists, then one will be decided on at the beginning of the Action.
2. Establish the relevant and available characterization techniques and their sequence for efficient characterization for analysis of devices aged in WG3. The WG1 will also contribute to this objective to leverage latest advances in characterization and avoid investigation of recently discovered failure paths.
3. Non-destructive characterization of devices and test structures at different stages of their degradation will be carried out successively or in parallel at different laboratories. Techniques to be considered for non-destructive testing include standard opto-electrical characterization of the OPV performance, in combination with imaging techniques to reveal the location of any failures. Chemical and surface and bulk structural characterization techniques of test structures will allow better understanding of the failure on the material level. These will be combined with physical and spectroscopic techniques to link the failure to physical parameters.
4. These tools are not only available at few locations but their often time-consuming and costly therefore the experts in WG3 and WG4 for ensure selection of only relevant samples.
5. Simulation and Modelling. Degradation can occur at different locations within the device, for example the light adsorbing layer, the electrodes, the many interfaces between layers, etc. Due to such complex structure and diverse degradation paths the application of modelling and simulation approaches is very important for the future advancement of the technology. In this respect, modelling and simulation will be used as a tool to understand OPV lifetime and results will be compared with experimental data obtained from the non-destructive and destructive analyses.
The results of the different characterization methods will be combined to aim at global understanding of the different degradation paths taking place in devices and test structures. This implies using the results both from destructive and non-destructive methods and compared to other reports in the literature.
Description of degradation mechanisms based on the large number of results obtained within the non-destructive analyses, with the aim at generalizing the finding for other materials and device structures. Suggestion to prevent these degradation routes and possible ways to derive accelerate testing methods for these particular processes. Results obtained in this WG will be combined with those observed in WG5 in order to arrive to more comprehensible degradation mechanisms.