Project: HELIOS

Title: "Higher efficiency through decreased light induced degradation and optimisation of amorphous silicon - HELIOS"

Short Description: Increasing the stability of amorphous silicon solar cells, simultaneously increases their efficiency. The study undertaken during this project led to the development of a new cell with a significantly improved stabilised efficiency.

The main objective of this is project, entitled HELIOS, was to study the problems associated with increasing the stabilised efficiency of amorphous silicon solar cells. The study has undertaken the first complete, fundamental study of the fabrication and improvement of the interfaces involved in tandem and single junction a-Si:H solar cells. This requires a thorough understanding of the plasma and plasma/interface interactions involved in a-Si:H fabrication. The primary aim of this project was to fabricate highly efficient, degradation resistant, single and tandem junction a-Si:H cells, further developing a-Si cell technology and deepening understanding of the physical processes at work in the p-i-n structure. The project aimed to use, for the first time, in situ analysis techniques for the study and improvement of the interfaces, along with the modelling of the performance and degradation of the interfaces and overall structure. It is anticipated that this will lead to a long-term improvement in the performance of a-Si:H solar cells. Furthermore, these advances will enable the production of tandem and single junction solar cells with an efficiency of 12% and degradation of less than 15%. A new micro-crystalline-amorphous n-layer, which can improve the overall performance of the double staked cell and the recombination junction by 8%, was also to be applied in this project.

Project Status: Completed