The incorporation of Zn into material which had been grown by means of ambient-pressure metalorganic vapor-phase epitaxy was studied as a function of the Zn-source flow rate, substrate orientation, and growth temperature. Under the growth conditions for device-quality layers, the level of Zn saturation varied with the substrate orientation. The kinetics of incorporation were analyzed by using a surface adsorption-trapping model. It was demonstrated that the Langmuir state of the adsorption-desorption process was not established during growth, due to interruption of the surface processes by layer growth. The existence of a saturation level under given growth conditions indicated that the Zn atoms were incorporated at defect sites instead of at the usual growth sites for In. Two parameters were used to characterize properties of the surface defect, such as the capture cross-section and the desorption time for Zn atoms.

R.A.Logan, S.N.G.Chu, M.Geva, N.T.Ha, C.D.Thurmond: Journal of Applied Physics, 1996, 79[3], 1371-7