In situ scanning tunneling microscopy observation of surface morphology of GaAs(001) grown by molecular beam epitaxy

Abstract

The surface morphology of molecular-beam-epitaxy-grown GaAs(001) has been investigated using in situ scanning tunneling microscopy and reflection high-energy electron diffraction. Films grown on nominally flat substrates at very slow growth rates display a multilevel system of terraces elongated along [11̄0], suggesting an edge energy anisotropy of the order of 10:1 and a preference for sticking at B-type steps.

Arsenic-rich GaAs(0 0 1) surface structure

“…Numerous other in situ STM and diffraction studies appeared that all confirmed the presence of structures consistent with the missing-dimer models [61,[123][124][125][126][127]54,[128][129][130][131][132][133][134][135]. However, there was discrepancy in the reports for which of the four missing-dimer models was actually observed.…”

Distribution of self-assembled InAs dots on patterned GaAs (100) substrates

“…Consequently, a large build up of material occurs at the intersection between the (1 0 0) top plane and the (3 1 1)B facet and this region will contain a high density of B-type step edges. Since B-type step edges have a higher sticking probability for adatoms than A-type step edges [16] the profile of the (1 0 0) top plane is more peaked at the facet/(1 0 0) top plane intersection on these mesas than on mesas in the ½0 11 direction. A large dot density, (1.370.2) Â 10 11 cm À2 is seen in this peaked region (Fig.…”

Interface-related in-plane optical anisotropy inGaAs/AlxChen1, Ye2, Wang3 et al. 2002Phys. Rev. B360452View full textAdd to dashboardCite

“…18 -22 It is found that atomic segregation always leads to wider alloy regions at AlAs-onGaAs interfaces as compared to GaAs-on-AlAs interfaces, and the AlAs-on-GaAs interfaces also exhibit anisotropic inplane structures or anisotropic interface defects elongated along ͓1 គ 10͔, 19,20 which are probably related to step energy anisotropy on the reconstructed GaAs surface. 23,24 We believe that both effects can occur in the GaAs/Al x Ga 1Ϫx As system and contribute to the observed optical anisotropy.…”