Deposition of a-Si:H Devices in a RTR System for Photovoltaic and Macroelectronic Applications
- PDF / 1,502,705 Bytes
- 6 Pages / 382.5 x 615.6 pts Page_size
- 14 Downloads / 206 Views
MAScholz, D. Peros and M. B6hm Institut fbr Halbleiterelektronik (IHE), Universittt GH-Siegen, Hdlderlinstr. 3, D-57068 Siegen, Germany ABSTRACT This work presents first results of potential manufacturing processes for integrated series connected hydrogenated amorphous silicon (a-Si:H) thin film solar modules and/or pindiode/TFT based macroelectronic circuits on flexible tapes. A RTR (Reel-To-Reel) deposition system on laboratory scale has been built, The system consists of seven metal sealed LIHV stinless steel chambers to obtain ultra high vacuum as a basis for high quality a-Si:H layers, in order to support continuous movement of the tape in the RTR process the chambers cannot be isolated from each other. The necessary pressure difference between the sputtering chambers and the PECVD (Plasma Enhanced Chemical Vapor Deposition) chambers is provided by pressure stages. They are optimized for high molecular flow resistance without any influence on the moving substrate tape. The back metal contacts and the semitransparent TCO (Transparent Conductive Oxide) contacts are deposited by rf magnetron sputtering, the a-Si:H film system is deposited by PECVD. Parallel to the film deposition a Nd:YAG laser patterning system is coupled into one chamber. This allows for instance a total manufacturing of integrated series connected solar modules in one system without breaking the vacuum. Our present investigations focus on the deposition of doped and intrinsic high quality a-Si:H based layers in neighboring chambers. The quality of semiconducting films deposited in adjacent chambers is studied with regard to potential contamination effects. INTRODUCTION
During the last decade many photovoltaic R&D efforts have been focusing on the optimization of amorphous silicon solar cells and modules. In comparison to mono- and polycrystalline devices the amorphous material shows better potential for the production of large area low cost PV modules. Despite this fact thin film solar cells have not yet gained considerable market share until now. They contribute only about one fifth to the total shipment of solar cells [11. One reason is the fact that in general there has been no significant increase in the demand for photovoltaic products. On the other hand the public attention is dominated and perhaps too much focused on lower efficiencies and stability problems of commercially available a-Si:H devices. In spite of the remarkable progress in the cell efficiency and stability the necessary transfer of results from research labs into production is insufficient and production rates for a-Si:H devices are relatively low. Furthermore, there are only a few companies worldwide working on related subjects [e.g. 2,3,41. Therefore innovative features and new products of a-Si:H thin film technology such as integrated series connection, flexible devices, macroelectronic, sensor and memory applications have not received the appropriate attention. In order to transfer the R&D results into production, this work aims at potential a-Si:H device manufacturi
Data Loading...
