Carbon rich dislocations in silicon
Carbon rich dislocations in silicon (close up)
Oxygen profile in silicon ingot

Silicon material: the cost pressure encourages the use of cheaper silicon feedstock, with more impurities, crystallised as quickly as possible, with more defects. It is becoming important to be capable of analysing and comparing the various qualities obtained, including previously widely ignored parameters like carrier mobilities. Imaging techniques have high potential, but improvements in the quantitative evaluation, agreed methods of data handling and quality measures to assure reliable answers from measurements are needed.