Fabrication of low-density self-assembled InAs quantum dots on InP(311)B substrate by molecular beam epitaxy

摘要

We developed a method of fabricating low-density InAs self-assembled quantum dots (QDs) on InP(311)B substrates by controlling the substrate temperature, and it was found that the lateral size and height of the InAs QDs increased with increasing substrate temperature. The density of the InAs QDs decreased to 1.28 ×10~(10)/cm~2, which corresponded to one QD per mesa structure, with a diameter of 100 nm. The photoluminescence (PL) property was also investigated, and it showed a clear spectrum even at room temperature at a 1.55 um fiber-optic communications system band. A blueshift of the PL peak wavelength was observed as the size of the InAs QDs increased. This unusual PL property can be explained by In segregation and In re-evaporation at relatively high growth temperature.