Thin tantalum films on crystalline silicon – a metallic glass

Thin amorphous tantalum films are prepared on Si(111) substrates in a metallic glassy state. The amorphous monoatomic state of the film is characterized by X‐ray diffraction studies. The glassy state leads to a negative t emperature c oefficient of the r esistivity (TCR) for low sample temperatures <200 K which is attributed to incipient localization. Above 200 K a positive TCR is observed as expected for a normal Boltzmann transport regime. Upon heating the Si substrate to 1200 K TaSi₂ is formed out of the amorphous tantalum film and the silicon substrate. The TaSi₂ layer is crystalline as evident from X‐ray diffraction data.