Our computers are getting ever faster and the possibilities that chips offer are becoming greater, so chip production machines have to become increasingly more advanced. A lithography machine, comparable to a highly precise slide projector, is an essential part of the chip production process. TNO has helped ASML, world leader in this field, realise prototypes for new lithography machines.
The new generation lithography machines use extreme ultraviolet light (EUV): light with a very short wavelength. This light is strongly absorbed in air and in the materials from which lenses are made. This implies for the new generation lithography machines that they will have to operate in contrast to their predecessors in a vacuum and use mirrors instead of lenses. Given the extreme complexity of the equipment, it is already difficult enough keeping the vacuum clean.
TNO has developed and built a number of important components of the EUV machines. The main similarity between all those components id the purity that has to be achieved. No foreign particles may enter the machine because these will disturb the image and result in chips that fail to work. But all kinds of organic material found in grease and glue also cannot be used. They cause vapour to form on the mirrors, so alternatives have to be sought. These requirements come on top of the extreme demands already imposed on this kind of system in terms of precision and reproduceability.