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This work describes progress towards achieving a flexible, high specific power and low-cost photovoltaic (PV) for emerging large area space applications. The study reports the highest conversion efficiency of 15.3% AM1.5G for a CdTe device on ultra-thin cerium-doped cover glass, the standard protective material for extra-terrestrial PVs. The deposition technique used for all of the semiconductor layers comprising the device structure was atmospheric pressure metal organic chemical vapour deposition. Improvements to the device structure over those previously reported led to a Voc of 788 mV and a relatively low series resistance of 3.3 Ω·cm2. These were largely achieved by the introduction of a post-growth air anneal and a refinement of the front contact bus bars, respectively. The aluminium-doped zinc oxide transparent conductive oxide, being the first layer applied to the cover glass, was subject to thermal shock cycling +80 to (-) 196°C to test the adhesion under the extreme conditions likely to be encountered for space application. Scotch Tape testing and sheet resistance measurements before and after the thermal shock testing demonstrated that the aluminium-doped zinc oxide remained well adhered to the cover glass and its electrical performance unchanged.

29th European Photovoltaic Solar Energy Conference and Exhibition; 2066-2071, This paper will look at the novel development of an affordable thin film cell for space use that promises an alternative path to the higher cost III-V solar cell development. The finished product will be a thin film cell of CdTe applied to a toughened large area flexible space qualified coverglass (Qioptiq CMG), the first time that this has been attempted. An efficiency of at least 14% AM0 is expected to be achieved. The programme has started with the successful application of the transparent conductive oxide to CMG glass. The work will then continue with the application of the cadmium telluride and the initial measurements of efficiency; further optimising the cell design and increasing the deposition area on the CMG glass; and then laser scribing the total area into series cells to produce higher voltage modules. In parallel with this the important environmental testing to meet the stringent conditions encountered in space will be undertaken. Further work on the completion of the programme will be discussed. This will include an array level development that exploits the thin film cell properties. In parallel with this flight opportunities on microsat missions will also be discussed in order for the cell type to gain flight heritage.