In this paper we report the development of a new and versatile ion implantation mask system which takes advantage of the
high precision offered by recent deposition methods. A stack of alternate layers of two different materials which can be
selectively etched is first deposited on the sample. Selective etching is then performed to remove a given number of layers
from the stack in the various region of the sample. Owing to a high etching selectivity between the two materials, the
thickness of the mask can be fixed very precisely in each region. During ion implantation, a different amount of ions will
pass through the mask to reach the sample, according to mask thickness over each region. This method therefore provides a
way to achieve a spatial control over the implantation dose, in a single implantation step. Thermal annealing can then be
performed to induce quantum well intermixing in the underlying heterostructure, which brings about a blueshift of the
emission wavelength. The results obtained with our method, which makes use of low energy ion implantation, for the
fabrication ofsingle step graded blueshifting of InP/InGaAs/InGaAsP integrated laser heterostructures are presented. We also
present a study of pairs of materials suitable for the mask fabrication, as well as the results of numerical simulations to
determine the appropriate thickness ofthe mask layers.
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