Mechanisms for implantation induced interdiffusion at In0.53Ga0.47As/In0.52Al0.48As heterointerfaces

Si, Al, B, Ga and Zn ions are implanted into 5.9 nm thick In0.53Ga0.47As/In0.52Al0.48 As quantum wells, and the interdiffusion of the constituent column III atoms (In, Ga and Al) due to subsequent annealing is studied by monitoring a shift in the peak energy of the photoluminescence from the well. Blue (AlGa) and red (InGa) shifts are observed, depending on the implant ion species, doses, energies or the depth of the well. These shifts occur almost in the initial stage (almost within 15 s) for the isothermal annealing and then level off for longer annealing times except in the case of Si ion implantation. This enhanced interdiffusion is due to the implantation induced defects (formation of column III interstitials and vacancies) and is explained in terms of the deposited energy of the implant ions at the well. As for Si, the interdiffusion does not stop but continues for longer annealing times and is explained in terms of impurity effects.