Samenvatting

This report is written to guide the reader step by step through the process of developing a heating stage and a iron mapping device for a photoluminescence setup, used to measure the lifetime of silicon wafers in solar cells. Subject specific terms will be explained throughout the report.

First, research has been done to determine how silicon wafers are produced, what influences their lifetimes, why does iron contamination occur in silicon and how does a photoluminescence setup work. After understanding these basics, the requirements for the desired implementations could be formulated. The strengths, weaknesses, opportunities and threats were analyzed by a SWOT analysis. Then several concepts were devised and afterwards judged by their different properties. There is decided to use a hot plate to make a heating stage and to research if the standard equipment of the PL-setup can be used to make iron maps.

After implementing the chosen concepts in the PL-setup, several tests were done to monitor the performance of the new features. The heating stage turned out to be a large improvement of the old hot plates that were used, especially in terms of homogeneity. Some further improvements of the accuracy can be made by using a vacuum pump to suck the silicon wafer to the hot plate surface. The laser in the PL-setup was found to be incapable for making iron maps, but further research and adjustments on the setup might give new opportunities. It is however determined that an external high intensity light source, in this case a flash head, can be used to replace the laser.