Effects of Mg-ion implantation in α-Al2O3 and α-Al2O3:Mg crystals: Electrical conductivity and electronic structure changes

被引:4
作者
Tardio, M. [1 ]
Colera, I. [1 ]
Ramirez, R. [1 ]
Alves, E. [2 ]
机构
[1] Univ Carlos III Madrid, Dept Fis, Madrid 28911, Spain
[2] Inst Tecnol & Nucl, Dept Fis, P-2866953 Sacavem, Portugal
关键词
Electrical conductivity; Ion implantation; Defects; Al2O3; X-ray photoemission spectroscopy; SINGLE-CRYSTALS; LATTICE LOCATION; THIN-FILMS; MAGNESIUM; MECHANISM; CENTERS; AL2O3; TIO2;
D O I
10.1016/j.nimb.2010.03.022
中图分类号
TH7 [仪器、仪表];
学科分类号
0804 ; 080401 ; 081102 ;
摘要
Undoped and Mg-doped alpha-Al2O3 single crystals were implanted with Mg ions, with an energy of 90 keV and a fluence of 10(17) ions/cm(2). DC electrical measurements using the four-point probe method, between 295 and 428 K, were used to characterize the electrical conductivity of the implanted area. Measurements in this temperature range indicate that the electrical conductivity after implantation is thermally activated with an activation energy of about 0.03 eV both in undoped and in reduced Mg-doped alpha-Al2O3 crystals, whereas the activation energy in oxidized Mg-doped alpha-Al2O3 crystals remains close to that before implantation. The I-V characteristics of the latter samples reveal a blocking behavior of the electrical contacts on the implanted area in contrast to the ohmic contacts observed in alpha-Al2O3 single crystals with the c-axis perpendicular to the broad face, where the Mg ions were implanted. We conclude that the enhancement in conductivity observed in the implanted regions is related to the intrinsic defects created by the implantation, rather than to the implanted Mg ions. The relationship between the oxygen vacancy concentrations at different stages of etching and the changes in the electronic structure, the chemical bonding, and the Al3+(2p)/O2-(1s) and Mg2+(1s)/O2-(1s) relative intensities was studied by X-ray Photoemission Spectroscopy. (C) 2010 Elsevier B.V. All rights reserved.
引用
收藏
页码:2874 / 2877
页数:4
相关论文
共 21 条
[1]  
BRIGGS D, PRACTICAL SURFACE AN, V1, P599
[2]   Characterization of MgO thin films grown by rf-sputtering [J].
Cáceres, D ;
Colera, I ;
Vergara, I ;
González, R ;
Román, E .
VACUUM, 2002, 67 (3-4) :577-581
[3]   Conductivity behaviour of Cr implanted TiO2 [J].
da Silva, RC ;
Alves, E ;
Cruz, MM .
NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION B-BEAM INTERACTIONS WITH MATERIALS AND ATOMS, 2002, 191 :158-162
[4]   Lattice location and electrical conductivity in ion implanted TiO2 single crystals [J].
Fromknecht, R ;
Auer, R ;
Khubeis, I ;
Meyer, O .
NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION B-BEAM INTERACTIONS WITH MATERIALS AND ATOMS, 1996, 120 (1-4) :252-256
[5]   Photoluminescence study of swift heavy ion (SHI) induced defect centers in sapphire [J].
Jheeta, K. S. ;
Jain, D. C. ;
Kumar, Ravi ;
Singh, Fouran ;
Garg, K. B. .
JOURNAL OF NUCLEAR MATERIALS, 2006, 353 (03) :190-192
[6]   Lattice location and electrical conductivity in Sb-implanted rutile [J].
Khubeis, I ;
Fromknecht, R ;
Meyer, O .
PHYSICAL REVIEW B, 1997, 55 (01) :136-141
[7]  
LEE KH, 1978, APPL PHYS LETT, V33, P274
[8]   Etching of amorphous Al2O3 produced by ion implantation [J].
McHargue, CJ ;
Hunn, JD ;
Joslin, DL ;
Alves, E ;
daSilva, MF ;
Soares, JC .
NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION B-BEAM INTERACTIONS WITH MATERIALS AND ATOMS, 1997, 127 :596-598
[9]   On the mechanism for dose rate dependence of stationary luminescence of F and F+ centres excited by electron beam in α-Al2O3 [J].
Meshakin, VI ;
Tanabe, T .
JOURNAL OF NUCLEAR MATERIALS, 2001, 297 (02) :149-152
[10]   Study of the surface electronic structure of MgO bulk crystals and thin films [J].
Ochs, D ;
MausFriedrichs, W ;
Brause, M ;
Gunster, J ;
Kempter, V ;
Puchin, V ;
Shluger, A ;
Kantorovich, L .
SURFACE SCIENCE, 1996, 365 (02) :557-571