Abstract
The stability of semiconductor epitaxial systems is discussed within a framework that clarifies connections between high pressure observations and 1 atm. growth conditions. Pressure-Raman results on interface mechanical stability in ZnSe/GaAs epilayers, and on phase stability in AlAs/GaAs superlattices are presented. In both cases the interface energetics play an important role. A theoretical analysis within a disordered interface picture offers insights into the occurence and prediction of metastable 1 atm. heterostructures.