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Timothy Groves
Dr. Timothy Groves
Associate Head of the Nanoengineering Constellation; Empire Innovation Professor of Nanoscale Science; Director, Center for Nanolithography Development

Listen to Professor Groves discuss the future of lithography on the Semiconductor International Movers and Shakers Podcast

Watch Professor Groves' "Inside CNSE" video interview on the Center for NanoScale Lithography.

Read Professor Groves' Nanotechnology Now article: CNSE Creates the Center for NanoScale Lithography in partnership with Vistec Lithography
Degrees:
  • Ph.D., Physics, University of Chicago, 1975
  • M.S., Physics, University of Chicago, 1970
  • B.S., Physics, Stanford University, 1968
Areas of research:
  • Electron beam physics
  • Particle beam optics
  • Nanoscale electron beam lithography
Previous experience:
  • Consulting Professor of Electrical Engineering, Stanford University, 1998-present
  • Director of Technology, Vistec Lithography (former Leica Microsystems Lithography), Cambridge, UK, 2000-2006
  • Senior Engineering Manager, E-beam Systems, IBM Semiconductor Research & Development Center, East Fishkill, NY, 1992-2000
  • Development Engineering Manager, IBM East Fishkill, 1987-1992
  • Advisory Engineer, e-beam system development, General Technology Division, IBM East Fishkill, 1983-1987
  • Technical Staff, Hewlett Packard Research Laboratory, Palo Alto, CA, 1978-1983
Description of research:

Professor Groves's research interests include the use of distributed, parallel, multiple electron beams for high throughput electron beam lithography; nanoscale electron beam lithography applications in physics, electron devices, and biology; particle beam optics; high brightness electron sources; and the development of high resolution, high throughput electron beam lithography systems. In 1998, while at IBM, he patented a concept for a distributed, parallel, multiple electron beam system. This concept has the potential of increasing the throughput of electron beam lithography by up to two orders of magnitude over existing technology, and is currently a topic of ongoing research. He also has developed a comprehensive course on particle beam optics, which includes both elementary and advanced levels. His courses on electron beam lithography and the optics of particle beams are available to audiences worldwide.

At Vistec Lithography, Professor Groves oversaw the development of the VB6 UHR EWF and the EBPG5000 Gaussian beam systems, and the SB351 and SB3050 variable shaped beam systems, which are used in a variety of applications including fine-line lithography for device research and development, low-volume manufacturing of devices for GMR magnetic data storage read heads, optoelectronics, photonics, compound semiconductors, telecommunications, security patterning, prototype device and process development for mainstream VLSI manufacturing, and manufacturing of 4X reticles for optical lithography and 1X templates for nanoimprint lithography.

At IBM, Professor Groves oversaw the development of the EL3 variable shaped beam system for 0.5 µm and 0.25 µm device technologies. During this period IBM used the EL3 system in its research, development, and manufacturing facilities worldwide. In particular, this system was used to manufacture the personalization wiring and via levels for the bipolar gate array logic chips, which formed the central processing unit in IBM's mainframe computers. The EL3 system was instrumental in enabling the success of IBM's high-end computers during this period.

He also oversaw the system development of IBM's EL4 variable shaped beam writer. This system incorporated the variable axis immersion lens, which enabled approximately a 5X throughput improvement over conventional projection lenses. The prototype EL4 system was installed in IBM's Advanced Mask Facility in Burlington, VT. It became the workhorse tool for patterning 1X x-ray masks, under the U.S. alliance for x-ray lithography development, funded by DARPA. The EL4 e-beam writer, together with the x-ray mask process developed in Burlington, successfully demonstrated full 130 nm groundrule devices in 1995, representing industry state-of-the-art performance.

Subsequent to the EL4 development, Dr. Groves oversaw the early development of the EL5 system. He also managed the systems group, which developed the PREVAIL e-beam projection tool. This tool was designed, built, integrated, and demonstrated under a development alliance with IBM and Nikon as partners.

Selected Publications:

T.R. Groves, The optics of charged particle beams, 285 pp., to be published.

T.R. Groves, Electron beam lithography, the first fifty years, and prospects for the future, invited presentation at the International Conference on Electron, Ion, and Photon Beam Technology and Nanofabrication, Anchorage, June 2, 2010.

H.J. Choi, T.R. Groves, Analysis of surface electromagnetic wave resonant structures for potential application in an array of compact photoelectron sources, J. Vacuum Sci. Technol. B 28(6), Nov. 2010, in press.

P.A. Sturrock, T.R. Groves, More variations on Aharonov-Bohm, Physics Today Letters, Volume 63, Number 4, p. 8, April 2010.

D.S. Pickard, C. Kenney, S. Tanimoto, T. Crane, T. Groves, R.F.W. Pease, A Monolithic Multi-Channel Secondary Electron Detector for Distributed Axis Electron Beam Lithography and Inspection, J. Vacuum Sci. Technol. B 25(6), Nov 2007

W.J. Daukscher, D. Mancini, K. Nordquist, D.J. Resnick, P. Hudek, D. Beyer, T.R. Groves, O. Fortagne, Fabrication of Step-and-flash Imprint Lithography Templates using a Variable Shaped Beam Exposure Tool, Microelectronics Engineering, Vol. 75, No. 4, p. 345-351, Nov 2004

J.G. Hartley, T.R. Groves, H.I. Smith, M.K. Mondol, J.G. Goodberlet, M.L. Schattenburg, J. Ferrera, A. Bernshteyn, Spatial-phase locking with shaped beam lithography, Rev. Sci. Instruments 74 (3), 1377-1379 (2003)

T.R. Groves, D. Pickard, B. Rafferty, N. Crosland, D. Adam, G. Schubert, Maskless electron beam lithography: prospects, progress, and challenges, Microelectronic Engineering, Elsevier (2002)

B. Rafferty, T.R. Groves, Wave optical calculation of electron probes, J. Vacuum Sci. Technol. B 19(6), 2607 (2001)

H.C. Pfeiffer, R.S. Dhaliwal, S.D. Golladay, S.K. Doran, M.S. Gordon, T.R. Groves, et. al., Projection reduction exposure with variable axis immersion lenses: Next generation lithography, J. Vacuum Sci. Technol. B 17(6), 2840 (1999)

T.R. Groves, Theory of Coulomb scattering in particle beams using Markov's method, J. Vacuum Sci. Technol. B 17(6), 2808 (1999)

J.G. Hartley, T.R. Groves, Chrome on glass mask writing at 75 KV with the IBM EL4+ system, J. Vacuum Sci. Technol. B 17(6), 2932 (1999)

T.R. Groves, R.A. Kendall, A Distributed, Multiple, Variable Shaped Beam Column for High Throughput Maskless Lithography, J. Vacuum Sci. Technol. B 16(6), (1998)

M.A. Sturans, T.R. Groves, et. al., EL5: one tool for advanced x-ray and chrome on glass mask making, J. Vacuum Sci. Technol. B 16(6), 3164 (1998)

J.G. Skinner, T.R. Groves, A. Novembre, H.C. Pfeiffer, R. Singh, Photomask Fabrication Procedures and Limitations in Handbook of Microlithography, Micromachining, and Microfabrication, Vol. 1, Microlithography, P. Rai-Choudhury (ed.), SPIE Optical Engineering Press, Bellingham, WA, Chap. 5, 377 (1997)

T.R. Groves, Theory of Beam Induced Substrate Heating, J. Vacuum Sci. Technol. B 14(6), 3839 (1996)

J.D. Rockrohr, R. Butsch, W. Enichen, M.S. Gordon, T.R. Groves, J.G. Hartley, H.C. Pfeiffer, Performance of IBM' s EL-4 E-beam Lithography System, Proc. SPIE, Vol. 2437, 160 (1995)

R. Butsch, W.A. Enichen, M.S. Gordon, T.R. Groves, J.G. Hartley, J.W. Pavick, H.C. Pfeiffer, R.J. Quickle, J.D. Rockrohr, W. Stickel, Performance Enhancements on IBM's EL-4 Electron Beam Lithography System, J. Vacuum Sci. Technol. B 13(6), 2478 (1995)

T.R. Groves, Efficiency Enhancement of Monte Carlo Simulation of Particle Beam Interaction by Separation of Stochastic and Continuum Contributions, J. Vacuum Sci. Technol. B 12(6), 3483 (1994)

H.A. Khoury, T.R. Groves, C.H. Plougonven, Product Dimensional Metrology and Pattern Defect Inspection in Microelectronics Manufacturing Diagnostics Handbook, A.H. Landzberg (ed.), Chap.5, 95 (1993)

H.C. Pfeiffer, D.E. Davis, W.A. Enichen, M.S. Gordon, T.R. Groves, J.G. Hartley, R.J. Quickle, J.D. Rockrohr, W. Stickel, E.V. Weber, EL-4, a New Generation Electron Beam Lithography System, J. Vacuum Sci. Technol. B 11(6), 2332 (1993)

T.R. Groves, Efficiency of Electron Beam Proximity Effect Correction, J. Vacuum Sci. Technol. B 11(6), 2746 (1993)

T.R. Groves, J.G. Hartley, H.C. Pfeiffer, D. Puisto, D.K. Bailey, Electron Beam Lithography Tool for Manufacture of X-ray Masks, IBM J. Research 37 (3), 411 (1993)

H.C. Pfeiffer, T.R. Groves, Progress in E-beam Mask Making for Optical and X-ray Lithography, Microelectronic Engineering 13 1-4, 141 (1991)

J.G. Hartley, T.R. Groves, H.C. Pfeiffer, Performance of the EL-3+ Mask Maker, J. Vacuum Sci. Technol. B 9(6), 3015 (1991)

T.R. Groves, Statistics of Pattern Placement Errors in Lithography, J. Vacuum Sci. Technol. B 9(6), 3555 (1991)

V.D. Beck, M.S. Gordon, T.R. Groves, A Fast Monte Carlo Beam Simulator Using Exact Coulomb Scattering, J. Vacuum Sci. Technol. B 7(6), 1438 (1991)

Selected Patents:

J.H. Boyden, D.R. Bradbury, G.A. Garrettson, T.R. Groves, L.R. Hanlon, A.P. Neukermans, Electron Beam Driven Ink Jet Printer, U.S. Patent No. 4,455,561

T.R. Groves, M.A. Sturans, G.J. Giuffre, D.G. Cullum, W. Stickel, Conductive Coated Electrostatic Deflection Plates, U.S. Patent 4,737,644

T.R. Groves, M.A. Sturans, H.C. Pfeiffer, W. Stickel, Telecentric Subfield Deflection with VAIL, U.S. Patent 4,859,856

S.K. Doran, W.A. Enichen, T.R. Groves, R.A. Kendall, H.A. Khoury, R.D. Moore, P.F. Petric, J.D. Rockrohr, Electron Beam Nano-metrology System, U.S. Patent 5,585,629

T.R. Groves, J.R. Maldonado, High Accuracy Fabrication of X-ray Masks with Optical and E-beam Lithography, U.S. Patent 5,756,234

R. Butsch, T.R. Groves, J.G. Hartley, Emulation Methodology for Critical Dimension Control in E-beam Lithography, U.S. Patent 5,916,716

T.R. Groves, R.A. Kendall, Distributed Direct Write Lithography System Using Multiple Variable Shaped Electron Beams, U.S. Patent 5,981,962

T.R. Groves, R.A. Kendall, Method for Writing a Pattern Using Multiple Variable Shaped Electron Beams, U.S. Patent 6,175,122

T.R. Groves, R.A. Kendall, Multiple Variable Shaped Electron Beam System with Lithographic Structure, U.S. Patent 5,962,859

A. Javer, T.R. Groves, Pattern Writing Equipment with Lens Sets, US 2005/0035308, GB 2,404,782 B, JP 2005-57275

N. Crosland, K-D Adam, T. Groves, J. Kristoff, B. Rafferty, G. Schubert, Dual-Mode Electron Beam Lithography Machine, US 7,053,388 B2, US 2005/0045836, GB 2,404,783 B, JP 2005-57269, DE 10 2004 032524.