abstract: |
The primary aim of this research project is to develop low cost photovoltaic systems. Routes to decrease “cost per Watt” are either to reduce the cost of the technology or to increase its efficiency. The first of these is addressed by the use of thin film technology for low cost deposition at low temperatures and with low material usage. The second is addressed by using multiple threshold devices to push efficiencies beyond the Schockley-Queisser limit for single band-gap PV cells. Our research activities will focus on the study and development of new electronic devices for both PV and optoelectronic applications. Materials of interest for PV system include compound II-VI thin film semiconductors, especially CdTe, transparent conducting oxides required for the fabrication of solar cells. The main goal of this project is the development of polycrystalline growth techniques of high efficiency CdS/CdTe and ZnSe/CdTe solar cells on the polyimide substrates in different substrate configurations. Continuation of joint research towards the development of commercially viable CdTe-based solar cells will be build on the research collaboration, which will successfully combine the glass and flexible solar-cell fabrication by close space sublimation (CSS) and hot wall technique (HWT) at Moldova State University, chemical bath deposition (CBD) and electrodeposition at University of Trieste, Italy with the characterization and analysis expertise in mechanism of CdCl2 treatment process, annealing ambient and formation of electronic properties of the layers and junction at Tallinn University of Technology, Estonia. Specific goals of the project are (1) increased cell efficiency to near 15% by improvements in electrical contact and reductions in window-layer absorption, (2) demonstration that cell stability can be reasonably extrapolated to several years, and (3) enhanced measurement and analysis capability in Moldova. |