SORTING OF III-V CONCENTRATOR SOLAR CELLS AS AN EFFICIENT TOOL FOR CPV MODULES MANUFACTURING

摘要

In the present status of the PV market, new approaches for introducing novelties and more efficient concepts are continuously under consideration. Concentration of light over the solar cell is certainly a very old topic but not old fashioned. The fast industrialization of current CPV modules are evidencing important fields of development not fully solved which call for immediate solutions. One of the needs is the measurements of III-V solar cells under manufacturing premises. In fact, an old topic extensively analyzed in literature for space applications, but has never been studied in depth for terrestrial applications and mass production scenarios. 4" Germanium wafers consisting of around 3000 triple junction solar cells are today being assembled in CPV modules at high volume (24 hours/day). Certainly, a bad strategy of assembly and manufacturing can be responsible of important energy losses at CPV module and tracking level. It is therefore a necessity to understand the performance of each solar cell before dicing and packaging. In these terms, this paper proposes and presents a fully automated solution of the measurement of solar cells at wafer level before starting the packaging procedure. The solution and procedure developed provides enough information of each solar cell and generates a wafer map suitable for further process in automatic die bonding machines. As a result, a fully automated process for very small solar cells (in the range of 1 mm~2) is currently in production in our manufacturing plant, allowing avoiding important losses at module level.