Bismuth surfactant mediated growth of InAs quantum dots by molecular beam epitaxy

Novel Dilute Bismide, Epitaxy, Physical Properties and Device Application

“…They therefore contributed the increased QD height to that Bi surfactant effect increases In adatoms surface diffusion length. Fan et al [112] hold the same view that In adatoms diffusion length is enhanced by Bi surfactant effect.…”

“…Because of the large atomic size, Bi would increase the surface tension [111] and enhance the adatom diffusion [112,113], making itself a good surfactant for III-V alloy growth. Acting as a surfactant, Bi atoms can smoothen surface and interface of GaAs and its heterostructures during growth.…”

“…Several works have utilized the surfactant effect of Bi to reduce defects and to enhance PL intensity [112,113,244]. In dilute bismides, the Bi induced PL intensity change is a hot topic at present.…”

“…So far there have only been a few studies about Bi's influence on InAs quantum dots (QDs) as summarized in Table 7 [112,114,[251][252][253] while Bi incorporation in nanowires (NWs) has just been reported recently [254]. Owing to δ-like density of states and excellent carrier confinement in QDs, InAs QD lasers possess a number of favorable device performance such as low threshold current density, high temperature stability and large differential gain, making them attractive for high-speed telecom laser applications.…”

Increased InAs quantum dot size and density using bismuth as a surfactant

“…22 For previous MBE-grown InAs QDs, introducing Bi simultaneously with InAs during QD growth resulted in improved QD uniformities, but lowered QD densities. 23 Thus, although the Bi surfactant has been found to consistently improve QD uniformity, the effects of Bi on QD densities and sizes have not been consistent.…”