Thermal roughening of GaAs surface by unwinding dislocation-induced spiral atomic steps during sublimation

被引：4

作者：

Kazantsev, D. M. ^{[1
,2
]}

Akhundov, I. O. ^{[1
]}

Rudaya, N. S. ^{[1
]}

Kozhukhov, A. S. ^{[1
]}

Alperovich, V. L. ^{[1
,2
]}

Latyshev, A., V ^{[1
,2
]}

机构：

[1] Rzhanov Inst Semicond Phys, Novosibirsk 630090, Russia

[2] Novosibirsk State Univ, Novosibirsk 630090, Russia

来源：

APPLIED SURFACE SCIENCE | 2020年 / 529卷

基金：

俄罗斯科学基金会;

关键词：

GaAs; Surface roughening; Screw dislocations; Spiral atomic steps; Surface diffusion length; MONTE-CARLO-SIMULATION; GAAS(001) SURFACE; HOMOEPITAXIAL GROWTH; SI(111) SURFACE; EQUILIBRIUM; DROPLETS; PERMEABILITY; EVAPORATION; DENSITY; MOTION;

D O I：

10.1016/j.apsusc.2020.147090

中图分类号：

O64 [物理化学（理论化学）、化学物理学];

学科分类号：

070304 ; 081704 ;

摘要：

Surface morphology evolution of flat GaAs epitaxial layers grown on mesa structured substrates is studied under annealing in the presence of a saturated Ga-As melt. At high temperatures T 700 degrees C, when the annealing conditions are shifted from the equilibrium towards sublimation, the initially flat surface roughens by unwinding spiral monatomic steps, which are induced by screw dislocations. This process leads to the formation of "inverted pyramid" spiral pits. Along with the spiral pits, the roughening consists in multilayer island formation on terraces, at the surface spots where the sublimation is inhibited. The mechanism of island formation is reproduced in the Monte Carlo simulation. The obtained data allowed us to estimate the relative undersaturation of -0.015 and Ga adatom diffusion length of 15 nm at T = 750 degrees C. Annealing at higher temperature T = 775 degrees C resulted in a peculiar "vortex"-like surface morphology, which consists in deep spiral pits covering the major part of the surface area.

引用

页数：6

共 3 条

[1] Thermal roughening of GaAs surface by dislocation-induced step-flow sublimation
Akhundov, I. O.
Kazantsev, D. M.
Kozhuhov, A. S.
Alperovich, V. L.
3RD INTERNATIONAL SCHOOL AND CONFERENCE ON OPTOELECTRONICS, PHOTONICS, ENGINEERING AND NANOSTRUCTURES (SAINT PETERSBURG OPEN 2016), 2016, 741
[2] Formation and interaction of dislocation-induced and vicinal monatomic steps on a GaAs(001) surface under stress relaxation
Akhundov, I. O.
Kazantsev, D. M.
Alperovich, V. L.
Rudaya, N. S.
Rodyakina, E. E.
Latyshev, A. V.
SCRIPTA MATERIALIA, 2016, 114 : 125 - 128
[3] Local monitoring of atomic steps on GaAs(001) surface under oxidation, wet removal of oxides and thermal smoothing
Akhundov, I. O.
Kazantsev, D. M.
Alperovich, V. L.
Sheglov, D. V.
Kozhukhov, A. S.
Latyshev, A. V.
APPLIED SURFACE SCIENCE, 2017, 406 : 307 - 311

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