Enhancement of Adhesion and Triboluminescent Properties of SrAl[sub 2]O[sub 4]:Eu[sup 2+] Films Fabricated by RF Magnetron Sputtering and Postannealing Techniques

Strongly adherent Sr Al 2 O 4 : Eu films were fabricated on the rough surface of an alumina substrate by a combination of the radio frequency (rf) magnetron sputtering technique and a post-thermal treatment. A crystalline Sr Al 2 O 4 : Eu 2 + film was obtained after annealing at 1000 ° C in a reduced atmosphere and it exhibited an intensely green photolumninscence (PL) and triboluminescence (Tribo-L), while an as-deposition film showed an amorphous state and a weakly red PL. It was found that the fabricated films possessed a strong durability of friction and exhibited no peeling, cracking, and breaking after Tribo-L measurements. The Tribo-L mechanism is discussed on the basis of the alternative carrier trap model presented by Clabau et al. [ Chem. Mater. , 17 , 3904 (2006) ].