Planar defects and double-domain epitaxy in epitaxial YSi2−x and ErSi2−x thin films on Si substrates
AbstractInterfacial reactions of Y and Er thin films on both (111)Si and (001)Si have been studied by transmission electron microscopy (TEM). Epitaxial rare-earth (RE) silicide films were grown on (111)Si. Planar defects, identified to be stacking faults on 
$$\left\{ {10\bar 10} \right\}$$
 planes with 1/6
$$\left\langle {\bar 12\bar 13} \right\rangle $$
 displacement vectors, were formed as a result of the coalescence of epitaxial silicide islands. Double-domain epitaxy was found to form in RE silicides on (001)Si samples resulting from a large lattice mismatch along one direction and symmetry conditions at the silicide/(001)Si interfaces. The orientation relationships are [0001]RESi2−x//
$$\left[ {1\bar 10} \right]$$
Si, 
$$(1\bar 100)$$
RESi2−x//(001)Si and [0001]RESi2−x/
$$[\bar 1\bar 10]$$
Si, 
$$(1\bar 100)$$
RESi2−x//(001)Si. The density of staking faults in (111) samples and the domain size in (001) samples were found to decrease and increase with annealing temperature, respectively.