Nano Structures On Si(111)induced By Irradiation Of KeV Ar~+ And Energy Loss Of KeV Ar~+ In Graphene

Nano technology has significant influence on many aspects such as microelectronics,computer,aerospace,energy,environment,bioengineering and so on.Self-organized nano structures,with regular morphology,controllable size and ordered arrangement,can be formed using the method of ion irradiation,which could make great progress in the fields of electronics,communications and computers.The study of energy loss on some special materials can not only improve the theory of energy loss,but also be applied to material analysis,material surface modification and semiconductor device.Thus in this work,I have performed the study of nano structures of Si?111?induced by the irradiation of keV Ar⁺ and the energy loss of keV Ar⁺ scattering on graphene.?1?The experiment has been performed using 1 keV Ar⁺,with beam density of 1.3?A/cm²,irradiating the single crystal Si?111?surface at the incidence angle of 20°.Then the nano structure has been characterized by the method of atomic force microscopy?AFM?.The evolution process of surface nano morphology has been found to change with the deposition dose of Ar⁺ projectiles.The shape and ordered nanodot pattern appeared when the deposition dose was 5×1016/cm².While the pattern disappeared when the deposition dose was larger than 5×10¹⁶/cm².One of the possible reason is that Bradley-Harper Model can govern the pattern when the deposition dose is smaller than 5×10¹⁶/cm².The beam density is so small that it cannot make the surface temperature come to the recrystallized point of silicon,which prevents the growth of surface nanodots.?2?The energy loss of keV Ar⁺ scattering on copper supported graphene was measured as a function of incident velocity by the method of time of flight?TOF?.The keV Ar would transmit through graphene and scatter on the copper surface.The energy loss of Ar almost linearly increases with the increase of incident velocity.The stopping power derived from the data of energy loss is similar to the electronic stopping power calculated by SRIM,but far away from the nuclear stopping power.It may indicate that the collision of Ar with graphene is the electronic process.The further analysis is in progress.