About Us > Faculty & Staff > Faculty > Bradley Thiel Professor of Nanoscience

Watch Professor Thiel's "Inside CNSE" video interview on the dual beam microscope and its applications

Read Professor Thiel's Nanotechnology Now article: Critical Dimension Environmental Scanning Electron Microscopy

Degrees:

• Ph.D. (Materials Science), University of Washington, Seattle, 1995
• M.S. (Materials Science), University of Washington, Seattle, 1990
• B.S. (Physics; Metallurgical Engineering), University of Washington, Seattle, 1987

Professional Experience:

• Professor of Nanoscience, College of Nanoscale Science and Engineering, University at Albany (2009 - )
• Director, Metrology Division, SEMATECH, Inc. (2007 - )
• Associate Professor of Nanoscience, College of Nanoscale Science and Engineering, University at Albany (2004 - 2009)
• Assistant Director of Research, Cavendish Laboratory, University of Cambridge, UK (1999 - 2004)
• Postdoctoral Research Associate, Cavendish Laboratory, University of Cambridge, UK (1995 - 1999)
  

Research Topics:

• Advanced metrology for semiconductor manufacturing
• Low vacuum scanning electron microscopy
• Electron/ion beam induced chemistry
• Ion-solid interactions

Research description:

Professor Thiel's research is concerned with the development of new characterization tools and methodologies appropriate for nanotechnology. Very often, physical properties are limited by structural, chemical, and electronic inhomogeneities on the nanometer scale. As devices and processes become smaller, it therefore becomes more and more critical to understand and measure structure - property relationships on atomic dimensions. Accordingly, the major thrust of Thiel's research is in developing electron, ion, and photon based tools and techniques.

Professor Thiel is also the Director of the Metrology Division of SEMATECH, one of the College's most important strategic partners. SEMATECH is the world's leading consortium of semiconductor manufacturers. It is the mission of the Metrology Division to deliver metrology solutions to the semiconductor industry to enable high yield production. The division works closely with the CNSE faculty and the National Institute of Standard and Technology (NIST) to develop new metrology tools and methodologies based on electron, ion, photon, and scanning probe techniques.

Low Vacuum Scanning Electron Microscopy
Electron microscopy is well established as one of the most powerful tools for the study of microstructure. Low vacuum instruments represent the latest evolution of scanning electron microscopes, and can offer a much richer variety of information on specimen characteristics. These tools allow routine examination of dielectric and insulating materials while avoiding complications due to charging effects. However, the processes that give rise to secondary electron emissions are complex, and not well understood for these materials. Furthermore, the presence of a low pressure gas in these instruments allows for a wide variety of electron-gas interactions that potentially also can be used to gain new insights into the nature of specimen.

Electron and Ion Beam Induced Chemistry
Charged particle beams can be used to initiate chemical reactions in precursor gases adsorbed onto substrates. Metallorganic precursors, for example, can be used to deposit metals. Other molecules can be used to etch and remove material. This approach therefore offers the possibility of direct-write fabrication of nanometer-scale structures. However, currently very little is understood about the physics of the electron-gas interactions, nor are the kinetics of the processes well known. Our group examines the effects of deposition conditions on the structure, composition, and physical properties of the deposit, as well as considering the role of different precursor chemistries.

Ion-Solid Interactions
Ion beam techniques are also emerging as key technologies for nanotechnology. Properly controlled, they can be used to both characterize and manipulate matter on the nanometer lengthscale. On the one hand, ion beams can be used to probe structure and chemistry in many of the same ways as electron beams. However, ion beams can also be used to deposit or remove material selectively. Underlying all of this is the need to understand ion-solid interactions, or how the kinetic and potential energies of an ion are imparted into a target material, and how this gives rise to the emission of electrons, photons, and secondary ions.

Selected Publications:

J. Li, M. Toth, K.A. Dunn, and B.L. Thiel,
Interfacial Mixing and Internal Structure of Pt-Containing Nanocomposites Grown by Room Temperature Electron Beam Induced Deposition
Journal of Applied Physics 107, xxx-xxx (2010). (in press)

A. Botman, C.W. Hagen, J. Li, B.L. Thiel, K.A. Dunn, J.J.L Mulders, S. Randolph, and M. Toth
Electron Postgrowth Irradiation of Platinum-Containing Nanostructures Grown by Electron-Beam-Induced Deposition from Pt(PF3)4
Journal of Vacuum Science & Technology B 27, 2759-2763 (2009).

V. Tileli, W.R. Knowles, M. Toth and B.L. Thiel
Noise Characteristics of Gas Cascade Amplification in Low Vacuum SEM
Journal of Applied Physics 106, 014904 - 014911 (2009).

J. Li, M. Toth, V. Tileli, K.A. Dunn, C.J. Lobo, and B.L. Thiel
Evolution of the Nanostructure of Deposits Grown by Electron Beam Induced Deposition
Applied Physics Letters 93, 023130-023133 (2008).

C.J. Lobo, M. Toth, R. Wagoner, B.L. Thiel, and M. Lysaght
High Resolution Radially Symmetric Nanostructures from Simultaneous Electron Beam Etching and Deposition
Nanotechnology 19, 025303-025309 (2008).

S.O. Kucheyev, M. Toth, T.F. Baumann, A.V. Hamza, J. Ilavsky, W.R. Knowles, C.K. Saw, B.L. Thiel, V. Tileli, T. van Buuren, Y.M. Wang, and T.M. Willey
Structure of Low-density Nanoporous Dielectrics Revealed by Low Vacuum Electron Microscopy and Small Angle X-ray Scattering
Langmuir 23, 353-356 (2007).

M. Toth, W.R. Knowles and B.L. Thiel
Secondary Electron Imaging of Non-Conductors with Nanometer Resolution
Applied Physics Letters 88, 23105-23107 (2006).

B.L. Thiel, M. Toth, R. Schroemges, J.J.S. Scholtz, G. van Veen and W.R. Knowles,
A Two Stage Gas Amplifier for Ultra-High Resolution Low Vacuum Scanning Electron Microscopy
Review of Scientific Instruments 77, 0337051-0337057 (2006).

B.L. Thiel and M. Toth
Secondary Electron Contrast Mechanisms in Environmental SEM: Characterization of Dielectric Substances
Journal of Applied Physics 97, 051101-051118 (2005). [Invited Focused Review]

B.L. Thiel
Imaging and Analysis of Dielectric Materials by Low Vacuum Scanning Electron Microscopy
Institute of Materials Reviews, Vol. 49, 109-122 (2004).

B.L. Thiel
Master Curves for Gas Amplification in Low Vacuum and Environmental Scanning Electron Microscopy
Ultramicroscopy, Vol. 99, 35-47 (2004).

A.M. Donald and B.L. Thiel
ESEM Contrast and Applications to Wet Organic Materials, in Impact of Electron and Scanning Probe Microscopy on Materials Research
NATO ASI series, D.G. Rickerby (ed.), Kluwer, 415-444 (1999). [Invited]

J.J. Scholtz, W.R. Knowles, B.L. Thiel, G. vanVeen, and R.P.M. Schroemges
Particle-Optical Device and Detection Means

US patent #6,972,412 B2 (ultra-high resolution secondary electron detector for low vacuum scanning electron microscopes) December 6, 2005.

Awards:

Sir Isaac Newton Trust Research Fellow, Cambridge University (1999 - 2004)