Lamellar-structured Ni-silicide film formed by eutectic solidification

Pt-doped NiSi-NiSi2 thin films in a uniform lamellar structure with a periodicity on the scale of a few tens of nanometers were formed on Si(001) substrates using a continuous laser scanning process. When the Pt-doped NiSi film was melted at high temperatures and was supercooled at high solidification rates (a high scanning speed of over 200 mm/s), a NiSi-NiSi2 lamellar structure evolved while interacting with the underlying Si substrate and following the classical eutectic solidification path. The lamellar spacing could be easily controlled by the laser scanning speed. In addition, the periodically formed, nearly single-crystalline NiSi and NiSi2 phases exhibited epitaxial relationships with each other and also with the Si(001) substrate. It is believed that this novel NiSi-NiSi2 lamellar structure can be used as a template for application areas requiring an electrode with a line/space pattern on the scale of a few tens of nanometers that can be prepared without using costly photolithographic processes. (C) 2018 Elsevier B.V. All rights reserved.