Vol 18 No 4, April 2009 1674-1056/2009/18(04)/1637-06
Chinese Physics B
c 2009 Chin. Phys. Soc. and IOP Publishing Ltd
Raman scattering studies on manganese ion-implanted GaN
Xu Da-Qing( ) , Zhang Yi-Men( ), Zhang Yu-Ming( Li Pei-Xian( ), and Wang Chao( ) ),
Key Laboratory of Ministry of Education for Wide Band-Gap Semiconductor Materials and Devices, School of Microelectronics, Xidian University, Xi'an 710071, China (Received 7 October 2008; revised manuscript received 5 November 2008) This paper reports that the Raman spectra have been recorded on the metal-organic chemical vapour deposition epitaxially grown GaN before and after the Mn ions implanted. Several Raman defect modes have emerged from the implanted samples. The structures around 182 cm1 modes are attributed to the disorder-activated Raman scattering, whereas the 361 cm1 and 660 cm1 peaks are assigned to nitrogen vacancy-related defect scattering. One additional peak at 280 cm1 is attributed to the vibrational mode of gallium vacancy-related defects and/or to disorder activated Raman scattering. A Raman-scattering study of lattice recovery is also presented by rapid thermal annealing at dierent temperatures between 700 C and 1050 C on Mn implanted GaN epilayers. The behaviour of peak-shape change and H full width at half maximum (FWHM) of the A1 (LO) (733 cm1 ) and E2 (566 cm1 ) Raman modes are explained on the basis of implantation-induced lattice damage in GaN epilayers.
Keywords: diluted magnetic semiconductors, gallium nitride, implantation, Raman spectroscopy PACC: 7550P, 7280E, 6170T, 7830
1. Introduction
Diluted magnetic semiconductors (DMSs) have attracted great interest in exploiting the spin of charge carriers in semiconductors because of their potential application to new devices based on spin polarized transport or integration of magnetic, optical, and electronic functions on a single chip. Mn-doped GaN materials are good materials for obtaining a Curie temperature (Tc ) higher than room temperature according to the theoretical calculation.[1] Mn ions are usually introduced into GaN either during growth or by ion implantation. A major obstacle to form DMSs material GaN:Mn has been the low solubility of manganese elements in GaN. Advantages of ion implantation are the selective doping of certain areas on the sample, the precise control of dopant concentration and depth distribution, and the introduction of a large number of elements without any limitation of solubility. Despite the fact that GaN is a host of very robust semiconductor, damage of the crystal lattice is induced by the implantation which must be removed by subsequent thermal annealing. Although some experimental studies on the GaN-based DMS have been reported, most

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