PP-TOFMS is a fast and reliable technique for depth profiling of rare earth doped ZnO thin films. Tb and Eu profiles are obtained with high sensitivity and high depth resolution. This type of information is typically provided by SIMS, RBS or depth profiling XPS but not as rapidly and readily and at a higher cost. Such profiles turn out to be powerful complementary information to understand photoluminescence data. This example extends to similar materials for photonics (lighting, display, solar energy industries) applications such as other wide bandgap semiconductors (SiC, GaN...), nitrides and oxynitrides layers, silicon nano-objects, glasses... doped with Yb, Y, Sm, Er, Nd, Pr, and Tm...