stable film, metastable film
A film often thins gradually to a thickness at which it either ruptures or converts abruptly to an equilibrium. Rupture under these conditions characterizes unstable films, whereas transition to an equilibrium characterizes (meta)stable films.
PAC, 1972, 31, 577. 'Manual of Symbols and Terminology for Physicochemical Quantities and Units, Appendix II: Definitions, Terminology and Symbols in Colloid and Surface Chemistry' on page 614 (