Model of noncontact scanning force microscopy on ionic surfaces

被引:122
作者
Livshits, AI
Shluger, AL
Rohl, AL
Foster, AS
机构
[1] Univ London Univ Coll, Dept Phys & Astron, London WC1E 6BT, England
[2] Curtin Univ Technol, Sch Appl Chem, AJ Parker Cooperat Res Ctr Hydromet, Perth, WA 6845, Australia
来源
PHYSICAL REVIEW B | 1999年 / 59卷 / 03期
关键词
D O I
10.1103/PhysRevB.59.2436
中图分类号
T [工业技术];
学科分类号
08 ;
摘要
We analyze the mechanisms of contrast formation in noncontact SFM imaging of ionic surfaces and calculate constant frequency shift scanlines of the perfect surfaces of NaCl, MgO, and LiF. The noncontact scanning force microscopy (SFM) operation is modeled by a perturbed oscillator using atomistic static and molecular-dynamics techniques for the force-field calculations. The electrostatic potentials of silicon tips contaminated by various atoms and that of a MgO tip are calculated using a periodic density-functional theory (DFT) method. Their analysis demonstrates that the presence of polar groups or chemisorbed species, such as oxygen atoms, makes the electrostatic forces acting on the surface ions from the Si tip one of the most important contributions to the image contrast. The (MgO)(32) cube model of the nanotip was found to be representative of a wide class of polar tips and used in the image calculations. The results of these calculations demonstrate that the contrast in noncontact SFM imaging of ionic surfaces is based on an interplay of the electrostatic and van der Waals forces. The main contributions to the contrast formation result from the interaction of the tip with the alternating surface potential and with the surface polarization induced by the electric field of the tip. The results emphasize the importance of the tip-induced relaxation of the surface ions in the tip-surface interaction and in image contrast. The noncontact SFM image of the Mg2+-cation vacancy defect on the LiF surface is calculated using the same method. [S0163-1829(99)08803-7].
引用
收藏
页码:2436 / 2448
页数:13
相关论文
共 68 条
[1]   EFFECT OF TIP PROFILE ON ATOMIC-FORCE MICROSCOPE IMAGES - A MODEL STUDY [J].
ABRAHAM, FF ;
BATRA, IP ;
CIRACI, S .
PHYSICAL REVIEW LETTERS, 1988, 60 (13) :1314-1317
[2]   Scanning force microscope with atomic resolution in ultrahigh vacuum and at low temperatures [J].
Allers, W ;
Schwarz, A ;
Schwarz, UD ;
Wiesendanger, R .
REVIEW OF SCIENTIFIC INSTRUMENTS, 1998, 69 (01) :221-225
[3]   Parametric tip model and force-distance relation for Hamaker constant determination from atomic force microscopy [J].
Argento, C ;
French, RH .
JOURNAL OF APPLIED PHYSICS, 1996, 80 (11) :6081-6090
[4]   Dynamic SFM with true atomic resolution on alkali halide surfaces [J].
Bammerlin, M ;
Luthi, R ;
Meyer, E ;
Baratoff, A ;
Lu, J ;
Guggisberg, M ;
Loppacher, C ;
Gerber, C ;
Guntherodt, HJ .
APPLIED PHYSICS A-MATERIALS SCIENCE & PROCESSING, 1998, 66 (Suppl 1) :S293-S294
[5]  
BAMMERLIN M, 1997, PROBE MICROSCOPY, V1, P3
[6]   MOLECULAR-DYNAMICS WITH COUPLING TO AN EXTERNAL BATH [J].
BERENDSEN, HJC ;
POSTMA, JPM ;
VANGUNSTEREN, WF ;
DINOLA, A ;
HAAK, JR .
JOURNAL OF CHEMICAL PHYSICS, 1984, 81 (08) :3684-3690
[7]  
Binks D.J., 1994, COMPUTATIONAL MODELI
[8]   Interpretation of force curves in force microscopy [J].
Burnham, N.A. ;
Colton, R.J. ;
Pollock, H.M. .
1600, (04)
[9]   How does a tip tap? [J].
Burnham, NA ;
Behrend, OP ;
Oulevey, F ;
Gremaud, G ;
Gallo, PJ ;
Gourdon, D ;
Dupas, E ;
Kulik, AJ ;
Pollock, HM ;
Briggs, GAD .
NANOTECHNOLOGY, 1997, 8 (02) :67-75
[10]   UNIFIED APPROACH FOR MOLECULAR-DYNAMICS AND DENSITY-FUNCTIONAL THEORY [J].
CAR, R ;
PARRINELLO, M .
PHYSICAL REVIEW LETTERS, 1985, 55 (22) :2471-2474