Core facility – low-temperature, high magnetic scanning probe microscopy

The Scanning Probe Microscope Laboratory is one of the cardinal facilities in RCAS. In order to enhance the coopration with NCTU, the SPM laboratory was built in Tin Ka Ping Photonics Center of NCTU. There are two members, an assistant research technical staff and an research assistant in the laboratory. Welcome all the colleagues of RCAS and all of the NCTU professors and studentsto visit and use our laboratory.

Shih-Hsin Chang

(Assistant Research Technical Staff)Experience：

*2007-2009 Scientific staff, Institute of Applied Physics, University of Hamburg, Germany

*2003-2007 Postdoctoral Fellowship, Institute of Physic Academia Sinica, Taiwan

An-Chun Liu

Research Assistant

Experience：

* Chung Hua University Mechanical Engineering

* 2007-2009 Industrial TechnologyResearchInstitute Materrial and Chemical Research Laboratories

          

Core facility – low-temperature, high magnetic scanning probe microscopy

After its birth in 1982 by G. Binnig and H. Rohrer (Nobel prize in physics, 1986 [1]), scanning probe microscopy (SPM), especially scanning tunneling microscopy/spectroscopy (STM/STS) is among the most important experimental tools in the study of surfaces at the nanoscale. SPM can not only image geometric structures but also unveil electronic structures of atoms, molecules, and nanostructures on surfaces with an atomic resolution [2]. With the help of lateral atom and molecule manipulation by the scan tip, artificial nanostructures can be formed and investigated [3].

In order to strengthen our research competitiveness, Research Center for Applied Sciences (RCAS) purchased a SPM system from attocube (http://www.attocube.com/) in autumn of 2009. Now the system is located on 101 Tien’s photonic building in National Chiao Tung University (our Hsinchu branch) and ready to serve. The system includes an insert, a cryostat, and controllers (Fig. 1), and has three scan modes: STM, atomic force microscope (AFM, both contact and noncontact modes), and tuning fork AFM. Samples from metals (AFM/STM), semiconductors (AFM/STM), to insulators (AFM) can be investigated.

Figure 2 shows the details of the insert. Samples can be moved in x (± 2.5 mm), y (± 2.5 mm), and z (~ 5 mm) directions with three independent positioners. Above these positioners is the scanner (x, y, and z) where we mount sample holders. With liquid helium (LHe) or liquid nitrogen (LN2), samples can be cooled from room temperature down to about 4 K (or 78 K) and an out-of-plane magnetic field up to 9 Tesla generated by a superconducting magnet can be applied if needed. Temperature-dependent measurements (4 K-RT) can also be carried out. In addition, the system has an additional fiber inside the insert. With a proper mounting of the fiber and analyzers, shining light on samples or collecting light eliminated from nanostructures is achievable.

In summary, this is a state-of-the-art system and, most importantly, it remains flexibility for other measurements and applications. Let’s the system help you to discover the frontiers of nanosciences.

References:

[1] G. Binnig, H. Rohrer, Ch. Gerber, and E. Weibel, Phys. Rev. Lett. 49, 57 (1982); Phys. Rev. Lett. 50, 120 (1983).

[2] W.B. Su, S.H. Chang, W.B. Jian, C.S. Chang, L.J. Chen, and T.T. Tsong, Phys. Rev. Lett. 86, 5116 (2001); S.H. Chang, W.B. Su, W.B. Jian, C.S. Chang, L.J. Chen, and T.T. Tsong, Phys. Rev. B 65, 245401 (2002); I.-S. Hwang, S.-H. Chang, C.-K. Fang, L.-J. Chen, and T.T. Tsong, Phys. Rev. Lett. 93, 106101 (2004); Phys. Rev. Lett. 94, 045505 (2005); S.-H. Chang, I.-S. Hwang, C.-K. Fang, and T.T. Tsong, Phys. Rev. B 77, 155421 (2008); A. Scarfato, S.-H. Chang, S. Kuck, J. Brede, G. Hoffmann, and R. Wiesendanger, Surf. Sci. 602, 677 (2008); S.-H. Chang, S. Kuck, J. Brede, L. Lichtenstein, G. Hoffmann, and R. Wiesendanger, Phys. Rev. B 78, 233409 (2008); J. Brede, M. Linares, S. Kuck, J. Schwöbel, A. Scarfato, S.-H. Chang, G. Hoffmann, R. Wiesendanger, R. Lensen, P.H.J. Kouwer, J. Hoogboom, A.E. Rowan, M. Bröring, M. Funk, S. Stafström, F. Zerbetto, and R. Lazzaroni, Nanotechnology, 20, 275602 (2009); S. Kuck, S.-H. Chang, J.-P. Klöckner, M.H. Prosenc, G. Hoffmann, R. Wiesendanger, ChemPhysChem, 10, 2008 (2009).

[3] J.A. Stroscio and D.M. Eigler, Science 254 1319 (1991); S.-W. Hla, K.-F. Braun, B. Wassermann, K.-H. Rieder, Phys. Rev. Lett. 93, 208302 (2004); V. Iancu, A. Deshpande, and S.-W. Hla, Phys. Rev. Lett. 97, 266603 (2006).

Figure caption:

Fig. 1: An attocube low-temperature, high-magnetic scanning probe microscope system.

Fig. 2: A close-up picture of the insert.