Ultrathin, sputter-deposited, amorphous alloy films of ruthenium and molybdenum

TL;DR

This study investigates ultrathin amorphous alloy films of ruthenium and molybdenum created via sputter deposition, revealing their amorphous structure and reduced surface roughness compared to pure element films.

Contribution

It provides detailed microscopy and diffraction analysis of sputter-deposited Ru-Mo alloy films, highlighting their amorphous nature and smoother surfaces at near-equal compositions.

Findings

Films are amorphous near 50:50 composition.

Amorphous films have lower roughness than pure element films.

Absence of grain structure explains reduced roughness.

Abstract

Microscopy and diffraction measurements are presented of ultrathin binary alloy films of ruthenium and molybdenum that are obtained by standard sputter deposition. For compositions close to Ru50Mo50, we find the films to be amorphous. The amorphicity of the films is accompanied by a significant reduction of the roughness with respect to the roughness of equally thick films of either ruthenium or molybdenum. We ascribe this to the absence of the grain structure that is characteristic of the polycrystalline films of the separate elements.