Focusing of molecular beams for the development of new tools for nanoscience and nanotechnology

Beams of neutral atoms or molecules at thermal energies are already known as a powerful probe for structural and dynamical analysis of solid surface properties, and in particular characteristics on the nanometer scale. By the implementation of suitable optical elements, based on nanometric features obtained by lithographic methods, the neutral beams can be focused. This opens up the possibility on the one hand of imaging with absolutely non-perturbing probes and on the other hand allowing the deposition of molecular species in submicrometric spots. The latter can be used to fabricate patterns on solid substrates with possible application in nanoelectronics, photonics and biochips. In this contribution we present state of the art measurements carried out with a neutral helium beam, for the development of a helium microscope. The best spatial resolution so far obtained was less than 1 ¿m and an improvement down to a few hundred nanometer is foreseen by controlling the virtual source size and the chromatic aberration of the optical element. Possible application of the technique will be the study of insulating and fragile samples such as organic membrane or biological samples. For example, so far it is just possible to image mainly the core structure and innermost electron shell of proteins and viruses. The invention of new helium scattering microscopes should give us the opportunity to also gather more detailed information about the outermost electron shell structure of such samples.