Preparation of silicon nanocrystallites by pulsed laser ablation

Abstract

We studied the formation process of silicon nanocrystallites prepared by laser ablation in hydrogen gas atmosphere. The silicon nanocrystallites are found to be covered with hydrogen atoms that terminate the dangling bonds on the surface of the nanocrystallites. It is shown that the reaction of hydrogen atoms with silicon atoms begins to take place about 100 ns after the start of laser irradiation, which is suggested to be the reason why the hydrogen atoms exist only on the nanocrystallite surface. The aggregation of the stable nanocrystallites produces a new class of coupled quantum dot systems, which are expected to show interesting phenomena.