Electron and hole separation in Ge nanocones formed on Si1−xGex solid solution by Nd:YAG laser radiation

Sphere-shaped SiGe micro/nanostructures with tunable Ge composition and size formed by laser irradiation*

“…The probable reason could be that the energy absorbed from the laser is transformed into heat energy and then transferred internally in the SiGe template, which will reshape the template into a more stable cluster. [26] Unlike the self-assembled SiGe islands with the shape of irregular islands or cones reported in previous researches, [13,18,24] this transformation process from SiGe template to regular spheres upon laser irradiation is very similar to the formation of metal self-organized nanoballs with thermal annealing, [27] and is mainly due to the loose precursors formed by deposition of Ge into the PSi. The main process is that the nonequilibrium state clusters reshape and attempt to obtain a local minimum energy state (regular spherical particle).…”

“…[15,16] It can thus induce various reactions in a highly selective and localized manner, and allow precise control of annealing in the desired region. This technology has been used to fabricate micro/nanostructures on substrate surfaces in several material systems [17][18][19] such as II-VI, [20] III-V [21] and IV compound semiconductors. [22] Laser irradiation has been used with SiGe materials to prepare micro/nanostructures with different aspect ratios and shapes, and these have been studied in depth.…”

“…[22] Laser irradiation has been used with SiGe materials to prepare micro/nanostructures with different aspect ratios and shapes, and these have been studied in depth. [13,18,23,24] However, most such structures are islands or other structures, and there are few reports on spherical structures formed by laser irradiation.…”