Electron-beam fabrication of 80-Å metal structures

Metal structures 100 Å high with sharply defined linewidths of 80 Å have been produced using an electron-beam fabrication process. A contamination resist pattern is written with a 5-Å 45-keV scanning electron beam in a 100-Å-thick Au-Pd film supported by a 100-Å carbon foil. The unprotected Au-Pd is removed by dc ion etching with 1-keV Ar ions. Unlike most electron-beam microfabrication processes, the resolution of the resulting structure is not limited by electron scattering, but by the grain size of the metal films. These structures should have direct application in a large number of device fabrication problems in electron and x-ray beam technology and they should provide masks for other microfabrication processes such as x-ray lithography.