The use of strain compensation layers in the growth of stacked quantum dot structures

Stacked quantum dot structures with a large number of layers are difficult to fabricate due to the large amount of strain in the dot layers. Dislocations can form from the large degree of strain, also a large amount of interdiffusion occurs during annealing. By inserting thin layers of GaP in the barriers of stacked dot structures the overall strain in the layers is reduced. These structures have an increased photoluminescence intensity. There is also a small blueshift in the photoluminescence of these structures, and a large narrowing of the luminescence linewidth. The structures with GaP strain compensation are shown to be more thermally stable.