The intermixing of double-barrier quantum wells by 50keV Ga+ implantation was studied experimentally and theoretically. It was found that, even at low doses (less than 1012/cm2), a considerably broadened emission peak with an appreciable luminescence blue-shift could be obtained. At medium doses (about 1013/cm2), very large blue-shifts of the order of 0.2eV were observed which retained a reasonable emission intensity. At high doses (above 3 x 1014/cm2), total intermixing occurred and no photoluminescence could be recovered. The photoluminescence blue-shifts after low-dose implantation were not affected by the annealing temperature, whereas the blue-shift at high doses depended greatly upon the annealing conditions. The data indicated heterogeneously enhanced interdiffusion that was based upon a defect cluster model. It was noted that close control of the annealing ambient and sample surface was important.

R.K.Kupka, Y.Chen: Journal of Applied Physics, 1995, 78[4], 2355-61