| If we incorporate a small amount of magnetic atoms into nonmagnetic semiconductor, the properties of the nonmagnetic semiconductor will change and the nonmagnetic semiconductor will exhibit magnetism, consequently diluted magnetic semiconductor will form. We also call it Semimagnetic Semiconductor (DMS). The magnetic atoms doped are called magnetic impurities and the nonmagnetic semiconductor is called the based material. The material studied in this paper is a novel kind of semiconductor material which is fabricated by incorporating magnetic transition metal ion Mn+ into IH-V semiconductor compound GaAs. Owing to the exchange and interaction between electrons of based semiconductor GaAs and magnetic impurity Mn, this kind of material combines the functionality of semiconductors with that of magnetic compounds, which shows particular structural, electrical and magnetic properties. So this material is promising in the application.In this paper, we used different doping means to prepare the Mn-doped GaAs material. Firstly, we incorporated Mn of different dose into GaAs by ion implantation, including the couple-ion implantation with Mn+ and C, then performed rapid thermal annealing in different temperature. Furthermore, we incorporated Mn into GaAs using different Mn sources (pure Mn and MnAs) by diffusion. Finally, we performed structural, electrical and magnetic measurements on these samples.At first, we investigated the photoluminescence characterization of theion-implanted samples by spectroanalysis, found that the ion implantation would damage the crystal lattice structure and affect the optical radiation of characteristic. Moreover, the crystal lattice structure will be restored after annealing, which can be determined by the change of fluorescence peak intensity and blue migration of wavelength.Secondly, we measured the electrical properties of the ion-implanted samples by Hall method (square carrier concentration, square resistance and carrier mobility). After comparing and analyzing, we can know that the electrical properties were affected by the difference of Mn dose, the implantation of C and the annealing temperature. Experimental results revealed that the carrier mobility increased with increasing of the annealing temperature, in the range of the annealing temperature from 650癈 to 850癈, which implied that the crystal lattice structure was damaged by ion implantation and restored after annealing. Furthermore, the square carrier concentration decreased, and the square resistance of the samples implanted by Mn+ and C increased with the raising of annealing temperature. These results indicated that the second phase such as MnGa, MnAs ferromagnets was formed by more Mn+ ions with increasing of the(GaAs)annealing temperature, so the Mn+ ions which can provide carriers decreased.And then, we measured X-ray diffractive spectrum of samples and investigated the crystal lattice structure of samples treated under different annealing temperature and different implantation condition comparing the diffraction peaks.Moreover, we observed the concentration profiles of the ion-implanted samples and the diffused samples by C-V method, and discovered that the carrier concentration decreased with increasing of the diffusion depth. Whereas, the peak concentration of the ion-implanted samples located at 0.248151 u m beneath the surface and the peak concentration of the diffused samples located at the surface. Furthermore, the carrier concentration of MnAs source diffused sample as high as 102%m3can be obtained, and the surface was much smoother compared with that of the pure Mn source diffused sample.At last, we observed the surface morphology and magnetism of the samples by Atomic force microscopy (AFM) and Magnetic force microscopy (MFM), the formation of MnGa and MnAs magnetic precipitates was discovered and the precipitates were affected by the conditions of implantation and annealing.
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