Deposition of MAX phase containing thin films from a (Ti,Zr)2AlC compound target

TL;DR

This study demonstrates the sputter deposition of MAX phases from a (Ti,Zr)2AlC target, revealing the formation of solid solution MAX phases and elucidating the growth mechanism of these thin films at high temperatures.

Contribution

It introduces a method for depositing MAX phases from a compound target and details the growth process and phase formation at various temperatures.

Findings

MAX phases successfully deposited from a compound target.

Formation of (Ti,Zr)2AlC and (Ti,Zr)3AlC2 phases confirmed.

Growth mechanism involves initial carbide formation followed by aluminide nucleation.

Abstract

This work reports on sputter depositions carried out from a compound (Ti,Zr)2AlC target, whereupon Al-containing (Ti,Zr)C thin films (30-40 nm in thickness) were deposited on MgO(111) and Al2O3(0001) substrates at temperatures ranging between 500 and 900 {\deg}C. The presence of Al within the carbide structure was evidenced by lattice parameter variations. Furthermore, chemical analyses showed that the Al distribution throughout the film thickness was fairly homogeneous. Thicker films (80-90 nm) deposited from the same compound target consisted of the pseudo-binary (Ti,Zr)C and intermetallic compounds in the Ti-Zr-Al system up to 800 {\deg}C, as well as solid solution MAX phases with different Ti:Zr ratios at 900 {\deg}C. X-ray diffraction and transmission electron microscopy showed that both (Ti,Zr)2AlC and (Ti,Zr)3AlC2 solid solution MAX phases were formed. Moreover, this work discusses the growth mechanism of the thicker films, which started with the formation of the mixed (Ti,Zr)C carbide, followed by the nucleation and growth of aluminides, eventually leading to the formation of the MAX phases, which was the primary objective of the sputter depositions.