6315.1:
Optical nano gratings for thin-film silicon solar cell
Abstract
This project is a continuation of the feasibility project (FP) 5810.1 and the preparation of a possible important project.
The aim of these 3 projects (i.e. feasibility project (FP), this continuation project and possible future full integrated project (IP)) is the improvement of the conversion efficiencies of thin-film silicon solar cells while maintaining cell manufacturing cost as low as possible. In the feasibility project (5810.1) we have been able to obtain the following results:
· for the first time, to the best of our knowledge, we could experimentally enhance the performance of thin film solar cells by the use of a substrate structured with nano-scale grating.
· the theoretical study strongly indicates that with quantitatively tuned nano-scale gratings it will be possible to reach performance improvements that are even higher than what has so far been obtained by the industrially standard, expensive polycrystalline random structures.
· solar cell fabrication has successfully been transferred from polyimide (PI) to PET substrates, without measurable loss in performance; on the thermoplastic PET substrate it becomes now conceivable that low-cost roll-to-roll replication could be in future used to apply the nano-grating technique at the industrial mass production level
At this point of time we propose a continuation of the FP (5810.1) to resolve two remaining issues which have not been covered so far. Once these issues have been addressed, we will be able to outline and plan the following phase of a full Top Nano 21 project called hereunder ”integrated project” (IP).
The remaining points to be addressed in this ”continuation project” are the following:
· technological :
1-analysis of the influence of the structure of the metallic layers on the optical performance
2-study of geometrical replication properties and
3-accurate analysis of the different solar cell layer properties.
· Theoretical: Efficient blaze grating structure to increase the current of thin amorphous silicon solar cell.
In parallel, we will use the time period of this continuation project to identify and motivate an additional project partner (or supplier), who will cover in the next phase (i.e. within the integrated project) the issues of fabrication and of low-cost replication of the required nano-scale gratings on PET substrate rolls.