Reentrant behavior of the density vs temperature of indium islands on GaAs(111)A

TL;DR

This study reveals a complex, non-monotonic relationship between indium island density and temperature on GaAs(111)A, influenced by phase transitions and island interactions, with implications for nanoscale material growth.

Contribution

It uncovers the reentrant density behavior of indium islands on GaAs(111)A and links it to phase transitions and island interactions, providing new insights into epitaxial growth processes.

Findings

Density increases with decreasing temperature down to 160°C

Density decreases below 160°C and increases again below 80°C

Indium islands have face-centered cubic structure below 160°C

Abstract

We show that the density of indium islands on GaAs(111)A substrates have a non-monotonic, reentrant behavior as a function of the indium deposition temperature. The expected increase in the density with decreasing temperature, indeed, is observed only down to 160 {\deg}C, where the indium islands undertake the expected liquid-to-solid phase transition. Further decreasing the temperature causes a sizeable reduction of the island density. An additional, reentrant increasing behavior is observed below 80 {\deg}C. We attribute the above complex behavior to the liquid-solid phase transition and to the complex island-island interaction which takes place between crystalline islands in the presence of strain. Indium solid islands grown at temperatures below 160 {\deg}C have a face-centered cubic crystal structure.