HIGH-CONDUCTIVITY AMORPHOUS TISI SUBSTRATES FOR LOW-TEMPERATURE ELECTRON-MICROSCOPY

To avoid problems with electrostatic charging, electrically conductive specimen support films or coatings must be used when observing non-conductive organic specimens by electron microscopy. At room temperature, microscopists typically use either carbon films or carbon-coated plastic films as specimen substrates. Such films have also been adopted for low-temperature microscopy. Recent measurements have shown that conventional carbon films have high electrical resistivity at low temperature. Thin titanium films have been used to provide improved electrical conductivity, but the structure of titanium films is excessively granular for high-resolution electron microscopy. With the hope of solving both problems, thin films of Ti88Si12 have been produced using a standard evaporation system. The deposited films are amorphous, as shown by electron microscopy, electron diffraction and differential scanning calorimetry. The electrical conductivity of the binary alloy films is nearly as high as that of pure titanium films. Therefore, these films appear to be appropriate substrates for low-temperature electron microscopy.