Initial Establishment Of A Multi-beam Ion Irradiation Facility And Investigation On The Magnetic Properties Of Si-based Diluted Magnetic Semiconductor

This work is supported by Accelerator Laboratory at Wuhan University. A multi-beam ion irradiation facility has been established initially and an appropriate device used for sample heating and insulating has been designed. On the other hand, by investigating the magnetic and structural changes of dilute magnetic semiconductors under treatment of different annealing temperature, possible origin of ferromagnetism is discussed.(1) Multi-beam ion irradiation facilities around the world have been described, as a reference to the establishment of multi-beam ion irradiation facility at Wuhan University. The facility consists of a1.7MV tandem accelerator, a200kV ion implanter and a50kV low-energy gas ion source. The ion beams from the tandem accelerator and the ion implanter beam have been introduced into the target chamber successfully, with an angle of45°.(2) The penning ion source of ion implanter has been improved. The beam intensity has been enhanced, and the iron ion beam has been gotten.(3) A device of sample heating and insulating applied in the multi-beam ion irradiation facility is designed. The maximum temperature of sample in target chamber has reached900?. The sample wouldn't be polluted during the heating process.(4) The magnetron sputtering and ion implantation technologies have been used in Mn-doped Si-based diluted magnetic semiconductor. The influence of different annealing conditions on the diluted magnetic semiconductor has been investigated. Using XRD, HRTEM and XAFS characterization methods, the local environment of the internal Mn atoms has been studied. Possible origin of ferromagnetism is discussed.