Resonances in the reaction ¹⁹F (α, p) ²²Ne have been used to detect and depth profile ¹⁹F in solid targets. Incident alpha particles in the range 2100-2500 keV were used and protons were detected at θ = 135° with a large solid angle surface barrier detector covered to stop elastically scattered alpha particles. This technique is a simple, nuclide specific probe and is particularly useful in detecting ¹⁹F in the presence of heavy elements such as GaAs where conventional Rutherford backscattering is ineffective. Examples using this technique on epitaxially grown thin films containing LaF₃ layers will be presented.