Stress evolution in GaAsN alloy films

We have investigated stress evolution in dilute nitride GaAs1−xNx alloy films grown by plasma-assisted molecular-beam epitaxy. For coherently strained films (x 2.5%, in situ wafer curvature measurements reveal a signature for stress relaxation. Atomic force microscopy and transmission electron microscopy measurements indicate that stress relaxation occurs by a combination of elastic relaxation via island formation and plastic relaxation associated with the formation of stacking faults.