Raman scattering study on diluted magnetic semiconductor Ga/sub 1-x/Mn/sub x/As prepared by Mn-ion implantation

Abstract

Raman scattering measurements have been performed in diluted magnetic semiconductor Ga 1-x Mn x As prepared by Mn-ion implantation, deposition, and post-annealing technique. It is found that the Raman spectrum measured from the implanted surface of the sample shows some new weak modes in addition to the GaAs-like modes which are observed from the unimplanted surface. The new vibrational modes observed are assigned to MnAs-like modes. The coupled LO-phonon plasmon mode, and Mn and As related vibrational modes caused by Mn-ion implantation, deposition, and post-annealing are also observed. Furthermore, the GaAs-like modes are found to be shifted by approximately 4 cm -1 in the lower frequency side, compared with those observed from the unimplanted surface.

Vibrational modes in Ga<inf>x</inf>Mn<inf>1&#x2212;x</inf>Sb studied by Raman spectroscopy

“…The phonon dispersion may experience disorder due to the implantation of Mn atoms in GaSb matrix resulting in the appearance of disorder activated mode. The existence of disorder phonon mode was also found in the Raman spectra measured from GaN layers implanted with Mn, Ar, P, C, Mg, and Ca ions [8][9][10]. Similar broad structure was found at 440 cm -1 in a previous study [13] performed in GaSb epilayer doped with dimethylzinc and assign to as second order combinational mode.…”

“…It is found in Fig. 1 that the spectra measured from the position a before and after etching the sample show phonon modes only at 235.6 and 226 cm -1 , which are identified as GaSb-like LO and TO modes, respectively [9,13]. Besides the GaSb-like LO and TO modes, some additional modes are observed at about 115 and 152 cm -1 in the spectra measured from the positions b and c before etching the sample.…”

“…This is because the Mn composition of the samples was very low. Although few Raman scattering studies have been performed in GaN prepared by ionimplantation technique [8][9][10], to the best of our knowledge, no body has made Raman scattering study on the vibrational modes in Ga 1-x Mn x Sb grown by Mn ions implantation and deposition, which is more useful in fabricating various devices. This article presents Raman scattering study on the vibrational properties of Ga 1-x Mn x Sb single crystals.…”

Raman spectroscopic determination of hole density in diluted magnetic semiconductor Ga<inf>x</inf>Mn<inf>1&#x2212;x</inf>Sb

“…However, coupled mode was not appeared in the spectra which may be due to the lower Mn concentration in the samples. The Mn compositiondependent shift in optical phonons was also found [10,19] in Ga 1-x Mn x As prepared by molecular beam epitaxy and Mn ions implantation, deposition and post annealing. In the present study, we did not find remarkable shift in optical phonons as a function of probing position.…”