About Facility
The Scanning Probe Microscope (SPM) Facility is one of eight Central Facilities operated by the Nebraska Center for Materials and Nanoscience (NCMN). These Central Facilities are university recharge centers that are open to all UNL researchers as well as external users with well defined user fees. The SPM central facility is located in the basement of Ferguson Hall (Room. 16) at the University of Nebraska (see Contact Info).
The SPM Specialist, Dr. Lanping Yue is in charge of the SPM central facility to maintain equipment, teach and assist users in the use of this equipment, analysis techniques and data interpretation and presentation. Research collaborations are welcome from all university research groups as well as companies in Nebraska and elsewhere.
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1. DI EnviroScope Atomic Force Microscope
The new Digital Instruments EnviroScope Atomic Force Microscope (ESCOPE) combines AFM imaging with environmental controls and hermetically sealed sample chamber to perform contact, lateral force, and TappingMode atomic force microscopy in air, vacuum, or a purged gas, as well as a heating environment. With advanced environmental capabilities, users can observe sample reactions to a variety of complex environmental conditions while scanning. In addition, the new system supports STM in air or vacuum, capable of imaging atomic steps on HOPG in air, (but not compatible with the high-temperature Heating Stage).
The preliminary specifications:
NanoScope V SPM control station combines advanced analog and digital circuit designs with real-time software to provide superior multi-tasking control to provide speed, sensitivity, resolution and functionality enhancements.
Sample stage range: 6mm XY; 14mm Z sample movement range
Sample Size: 30mm X-Y, 12mm Z
Scan Size: horizontal imaging area of 90-micron X-Y nominal maximum and a vertical range of 5-micro nominal maximum.
Optics: Improved on-axis video optics with 0.5mm field of view
Vacuum: A Varian Turbo-V70 vacuum pump down time can be as quick as 10 minutes, depending on ESCOPE chamber cleanliness, with high vacuum capability to 10-5 Torr.
High Temperature Heating Stage with Lakeshore Model 331 temperature controller included in the ESCOPE system. Temperature range:
Room temperature (RT) to 185 °C in ambient environment
RT to approx. 300 °C nominal at the sample, ~ 275 °C in Vacuum.
2. DI Nanoscope IIIa Dimension 3100 SPM system
The Digital Instruments Nanoscope IIIa Dimension 3100 SPM system is a multifunction scanning probe microscope for materials imaging and characterization. DI 3100 SPM utilizes atomic force microscopy (AFM), magnetic force microscopy (MFM), lateral force microscopy (LFM), and scanning tunneling microscopy (STM) with the scanning tunneling spectroscopy (STS) techniques to measure surface characteristics for a large variety of materials, such as nanoparticles, polymers, DNA, semiconductor thin films, magnetic media, optics and other advanced nanostructures. SPM can provide a wealth of information from topography, surface morphology, to magnetic phase or friction analysis, including line width, grain size, pitch and depth, roughness measurements, sectioning of surfaces, power spectral density, particle analysis, surface defects, and pattern recognition, etc.
This facility contains the following equipments:
1) Dimension 3100 SPM Microscopy;
2) NanoScope III System Controller;
3) D3100 Microscope Electronics Box; and
4) Dual-monitor Computer System, for data analysis, data imaging, data manipulation, and data presentation.
Our MFM equipment can scan samples in applied external magnetic fields, which is useful for high resolution magnetic domain imaging under magnetic field. The available fields using permanent magnets are -0.24 T to 0.24 T perpendicular to the sample and -0.45 T to 0.45 T parallel to the sample. The resolution of our MFM tips modified by Focused-Ion-Beam (FIB) milling is around 15 nm, which is currently state-of-the-art capability.
Selected Applications
18. LanpingYue, Zhen Li, Roger Kirby, David Sellmyer, "MFM studies of interlayer exchange coupling in Co/Ru/Co films: Effect of Ru layer thickness", Ultramicroscopy 109 (2009) 1040-1043
Magnetic domain structures of as-deposited Co/Ru/Co trilayers with different thickness of Ru interlayer
17. Jun Zhang, R. Skomski, L. P. Yue, Y. F. Lu, and D. J. Sellmyer, "Structure and magnetism of V-doped SnO2 thin films: effect of the substrate", J. Phys.: Condens. Matter 19, 256204 (2007).
16. Haojing Lin, Jiashi Yang, Li Tan, et al. "Collective Buckling of Periodic Soft Nanostructures on Surfaces and Promotion for Nanolithography", J. Phys. Chem. C 111 (36), 13348 -13353 (2007).
J. Phys. Chem. C 111 (36), September 13, 2007 Cover
15. J. Williams, B. Reynolds, K. Keefe, and J. Anderson, "Fluorescent Structure DNA Nanoparticles Functionalized with Phosphate-Linked Nucleotide Triphosphates", Technical Proceedings Nanotech 2, 239 (2007).
DNA imaged on mica with AFM TappingMode in air, 1 mm scan size, height 2nm.
14. Nikolay I. Polushkin, Steven A. Michalski, Lanping Yue, and Roger D. Kirby, "Evidence of long-wavelength collective excitations in magnetic superlattices", Physical Review Letters 97, 256401 (2006).
13. Aliekber Aktag, S. Michalski, Lanping Yue, R. D. Kirby, and Sy-Hwang Liou, "Formation of an anisotropy lattice in Co/Pt multilayers by direct laser interference patterning", Journal of Applied Physics 99, 093901 (2006).
MFM images of CoPt film in remanent state (left) and in a perpendicular 180 Oe field (right), scan size 10 mm.
12. X. Rui, J. E. Shield, Z. Sun, L. Yue, Y. Xu, D. J. Sellmyer, Z. Liu, and D. J. Miller, "High energy product exchange-spring FePt/Fe cluster nanocomposite permanent magnets", J. Magn. Magn. Mater. 305, 76-82 (2006).
AFM image of sub-10nm Fe clusters
11. M. Bai, M. Poulsen, and S. Ducharme, "Effects of annealing conditions on ferroelectric nanomesa morphology and self-assembly", J. Physics: Condensed Matter 18, 7383-92 (2006).
AFM images of copolymer LB films with different annealing conditions
10. A. Brauth, D. Keavney, J. Burton, K. Janicka, E. Tsymbal, L. Yuan, S. Liou, and S. Adenwalla, "Origin of the interlayer exchange coupling in [Co/Pt]/Nio/[CoPt] mulitilayers studied with XAS, XMCD, and micromagnetic modeling”, Physical Review B 74, 054419 (2006).
9. A. Brauth, L. Yuan, J. Burton, K. Janicka, E. Tsymbal, S. Liou, and S. Adenwalla, "Domain overlap in antiferromagnetically coupled [Co/Pt]/NiO/[Co/Pt] multilayers", Applied Physics Letters 89, 202505 (2006).
MFM images of coupled Co/Pt multilayers with different thickness of NiO interlayers
8. Y. C. Sui, W. Liu, L. P. Yue, X. Z. Li, R. Skomski, and D. J. Sellmyer, "Template-mediated assembly of FePt L10 cluster under external magnetic field", Journal of Applied Physics 97, 10J304 (2005).
MFM image of a magnetic array of FePt dots generated by Template-Mediated Self-Assembly.
7. J. Li, Y. Luo, M. Bai, and S. Ducharme, "Nanomesa and Nanowell Formation in Langmuir-Blodgett Polyvinylidene Fluoride Trifluoroethylene Copolymer Films", Applied Physics Letters 87, 213116 (2005).
6. M. Bai and S. Ducharme, "Ferroelectric Nanomesa Formation from Polymer Langmuir-Blodgett Films", Applied Physics Letters 85, 3528-30 (2004).
5. Z.Y. Liu, Lanping Yue, D. J. Keavney, and S. Adenwalla, "Oscillations of interlayer exchange coupling in [Pt/Co]n/NiO/[CoPt]n multilayers with perpendicular anisotropy: dependence on NiO and Pt thicknesses", Physical Review B 70, 224423 (2004).
4. L. Gao, L. P. Yue, T. Yokota, R. Skomski, S. H. Liou, H. Takahoshi, H. Saito, and S. Ishio, "Focused Ion Beam Milled CoPt Magnetic Force Microscopy Tips for High Resolution Domain Images", IEEE Trans. Magn. 40(4), 2194-2196 (2004).
MFM images of high-density recording media taken with FIB milled CoPt tip.
3. K. Sorge, A. Kashyap, R. Skomski, L. Yue, L. Gao, R. Kirby, S. H. Liou, and D. J. Sellmyer, "Interaction and Switching Behavior of Anisotropic Magnetic Dots", Journal of Applied Physics 95(11), 7414-7416 (2004).
2. M. L. Yan, X. Z. Li, L. Gao, S. H. Liou, D. J. Sellmyer, R.J.M. van de Veeedonk, K. Wierman, "Fabrication of nonepitaxially grown double-layered FePt:C/FeCoNi thin films for perpendicular recording" Appl. Phys. Lett. 83, 3332 (2003).
1. Y. Sui, L. Yue, R. Skomski, X. Li, J. Zhou and D. J. Sellmyer, "CoPt Hard Magnetic Nanoparticles Film Synthesized by High Temperature Chemical Reduction", Journal of Applied Physics 93(10), 7571-7573 (2003).
