Specifics of MOCVD Formation of In[sub x]Ga[sub 1 – ][sub x]N Inclusions in a GaN Matrix.

MOCVD-grown heterostructures with one or several In[sub x]Ga[sub 1-x]N layers in a GaN matrix have been studied by transmission electron microscopy. In heterostructures with thick InGaN layers, a noncoherent system of domains with lateral dimensions (∼50 nm) on the order of the layer thickness (∼40 nm) is formed. In the case of ultrathin InGaN inclusions, nanodomains coherent with the GaN matrix are formed. The content of indium in nanodomains, determined by the DALI method, is as high as x ≈ 0.6 or more, substantially exceeding the average In concentration. The density of the nanodomains formed in the structures studied is n ≈ (2-5) x 10[sup 11] cm[sup -2]. In the structures with ultrathin InGaN inclusions, two characteristic nanodomain sizes are observed (3-6 and 8-15 nm). [ABSTRACT FROM AUTHOR]