Study On Laser-assisted Induced Ga Migration Behavior

The compound semiconductor materials represented by GaAs have a larger band gap and a faster electron mobility.Therefore,GaAs-based semiconductor lasers,quantum dot infrared detectors,high efficiency infrared light-emitting diodes and solar cells have shown a wide range of applications.At present,one of the main techniques for the preparation of nanometer semiconductor structures is molecular beam epitaxy with the advantage of precisely material controlling at atomic level in the ultra-high vacuum environment.However,the quantum structure grown on the basis of the traditional Stranski-Krastanov mode(SK mode)is difficult to control thenucleation position many limitations in practical application.Therefore,in the past two decades,droplet epitaxy(DE),because of its wider range of material growth,easy-control of material density and facile fabrication of novel material structure,has been extensively studied,such as: droplet epitaxial growth technology,surface plasmids,droplet autocatalytic growth nanowires and droplet etching preparation templates and so on.However currently,most of the DE-related research have focused on the growth kinetic behavior of the required nanostructures from the droplet rather than the dynamics of the droplets themselves.Therefore,in this paper,we used in situ pulse-laser to radiate Ga-droplet surface on GaAs(001)prepared by MBE and then the dependence of droplet growth,migration and fusion on laser density and growth temperature was researched.It was proved that pulsed-laser could be used to in-situ modify the density and size of the droplets thus providing a new technology for the artificial controlled DE in the future.Artificially controlled growth of droplet epitaxy technology to prepare.