Abstract
A MBE-prepared Gallium (Ga)-droplet surface on GaAs (001) substrate is in situ irradiated by a single shot of UV pulsed laser. It demonstrates that laser shooting can facilely re-adjust the size of Ga-droplet and a special Ga-droplet of extremely broad size-distribution with width from 16 to 230 nm and height from 1 to 42 nm are successfully obtained. Due to the energetic inhomogeneity across the laser spot, the modification of droplet as a function of irradiation intensity (IRIT) can be straightly investigated on one sample and the correlated mechanisms are clarified. Systematically, the laser resizing can be perceived as: for low irradiation level, laser heating only expands droplets to make mergences among them, so in this stage, the droplet size distribution is solely shifted to the large side; for high irradiation level, laser irradiation not only causes thermal expansion but also thermal evaporation of Ga atom which makes the size-shift move to both sides. All of these size-shifts on Ga-droplets can be strongly controlled by applying different laser IRIT that enables a more designable droplet epitaxy in the future.
Highlights
With the increasing development of both fundamental physics and practical application, it is of great demands for people to achieve various devices
While in IR2 (Fig. 1c) and IR3 (Fig. 1d), the droplet size begins to be modified by the laser shooting
In conclusion, we have conducted a research on MBE in situ shooting on the Ga-droplets at 180 °C by pulsed laser and demonstrated that the laser-shooting can facilely and high-efficiently adjust the size distribution of droplets
Summary
With the increasing development of both fundamental physics and practical application, it is of great demands for people to achieve various devices. Increasing temperature will intensify the droplet etching into substrate drastically [26–29]. By this kind of nano-drill, the elements of droplets will be consumed before the subsequent crystallization and a parasitic structure of nano-hole will develop beneath the droplet which may pollute the target quantum structure. To raise temperature may destroy the droplets, but to push them growing bigger makes people has to do so, its an irreconcilable contradiction in the traditional droplet epitaxy. It makes great significances to find a technology, with temperature-independence, to modify the droplet size
Sign-in/Register to view highlights & summary Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
