To make progress in contact formation, a new approach is necessary. Almost no improvement has been made in this topic for the last 10 years, the same pastes are being used as 10 years ago.
To be able to use environmentally benign components, to accomplish higher efficiencies, and a robust process, a scientific approach was followed. Hypotheses were made to predict the functions of components in paste and to predict behaviour during processing. These hypotheses were tested by simple experiments and detailed characterisation.
Using the results from these measurements and experiments, models were made to describe the behaviour of components and the complete system during deposition, drying and sintering. These models were tested and used to guide the development to improve contact formation. One of the outcomes of our scientific approach is the way we experiment and test new metallisation components and processes. A simple test methods on components is used to see whether they perform as predicted and to avoid expensive, large-scale experiments involving cell processing with many process settings.