(In,Mn)As

(In,Mn)As Nanostructures

S. P. Guo, H. Ohno, A. Shen, F. Matsukura, and Y. Ohno, "Self-organized (In,Mn)As diluted magnetic semiconductor nanostructures on GaAs substrates," Applied Surface Science, vols. 130-132, pp. 797-802, 1998.

We have grown (In,Mn)As quantum dots QDs on GaAs (100), (211)B and (311)B substrates. The observation of reflection high energy electron diffraction pattern and atomic force microscopy measurement confirmed the formation of the (In,Mn)As QDs. The structure grown on GaAs (100) showed a broad range of dot sizes with irregular shape. For the structure grown on GaAs (311)B, (In,Mn)As QDs with bimodal size distribution were observed. The (In,Mn)As QDs grown on GaAs (211)B showed improved size uniformity compared to those grown on GaAs (100) and (311)B.

Fig. 1. RHEED patterns of (a) GaAs (100) buffer layer, (b) 2 ML of (In,Mn)As on GaAs (100) right after growth, (c) 8 ML of (In,Mn)As on GaAs (100) right after growth and (d) 8 ML of (In, Mn)As on GaAs (100) after 60 s growth interruption. All taken along [011] azimuth at 350^oC

Fig. 2. RHEED patterns of (a) GaAs (211)B buffer layer, (b) 6 ML₂₁₁ of (In,Mn)As on GaAs (211)B right after growth and (c) 6 ML₂₁₁ of (In, Mn)As on GaAs (211)B after 60 s growth interruption, (d) GaAs (311)B buffer layer, (e) 5 ML₃₁₁of (In,Mn)As on GaAs (311)B right after growth and (f) 5 ML₃₁₁ of (In, Mn)As on GaAs (311)B after 60 s growth interruption. All taken along [011] azmith at 350^oC.

Fig. 3. 1x1 µm² AFM images of (a) 8 ML of (In, Mn)As grown on GaAs (100), (b) 6 ML₂₁₁ of (In,Mn)As grown on GaAs (211)B, (c) 6 ML₂₁₁ of InAs and (d) 9 ML₂₁₁ of (In,Mn)As grown on GaAs (211)B. All grown at 350^oC.

Fig. 4. 1x1 µm² 3D AFM image of 9 ML₂₁₁ of (In,Mn)As grown on GaAs (211) Bat 350^oC.

Table 1
The average dot density, the average lateral size and the average height of (In,Mn)As (or InAs) QDs grown at 350^oC on various GaAs substrates.

Other Related References

S. P. Guo, A. Shen, H. Yasuda, Y. Ohno, F. Matsukura, and H. Ohno, "Surfactant effect of Mn on the formation of self-organized InAs Nanostructures," Journal of Crystal Growth, vol. 208, pp. 799-803, 2000.
S. P. Guo, A. Shen, F. Matsukura, Y. Ohno, and H. Ohno, "InAs and (In,Mn)As nanostructures Grown on GaAs (100), (211)B, and (311)B Substrates," Journal of Crystal Growth, vol. 201-202, pp. 684-688, 1999