NANOLITHOGRAPHIC PATTERNING OF METAL-FILMS WITH A SCANNING TUNNELING MICROSCOPE

We have developed a new technique, which allows to pattern thin evapor ated Au films at the nanometer scale with a scanning tunnelling micros cope (STM). The STM tip is used to expose a very thin layer of omega-t ricosenoic acid, which has been deposited on top of the Au films using the Langmuir-Blodgett technique and acts as an electron sensitive, ne gative resist. We have fabricated narrow Au lines with a width down to 15 nm and we have checked that our STM lithography does not degrade t he metallic properties of the Au films. The power of our lithographic patterning technique is nicely illustrated by the fact that we can att ach electrical gold contacts to a small bundle (total diameter of 50 n m) of carbon nanotubes (''Buckey tubes'') and measure the electrical r esistance of the bundle as a function of temperature and magnetic fiel d.