MINT Seminar Page

MINT seminars (EE 8192), Spring 1999

Title: SPIN DEPENDENT TUNNELING MATERIALS AND THEIR APPLICATIONS
Presenter: Dr. Mark Tondra, Non-Volatile Electronics, Eden Prairie, MN
Date: May 14, 1999, Friday
Time: 1:25 P.M.
Room: 102 Mech. Eng.

Abstract

Spin Dependent Tunneling (SDT) materials are the latest in the line of ferromagnetic magnetoresistive materials which includes Anisotropic Magnetoresistance (AMR) and Giant Magnetoresistance (GMR). As such, they have potential applications in a wide range of sensing and electronics applications including magnetic field sensors, Magneto- resistive Random Access Memory (MRAM), programmable logic arrays, hard drive read heads, and magnetoresistive isolation devices. NVE has a focused effort in applying SDT materials the ultra-low magnetic field sensor application. This talk will address some specific features of these sensors including the biasing mode and micromagnetic design of the SDT elements, the use of integrated biasing coils and flux concentrators, and the spectral noise density and its effect on the ultimate achievable sensitivity. A noise floor of 1 x 10^-8 Oe / rt. Hz is achievable, particularly at higher frequencies. The applicability of SDT materials to the other applications will also be addressed in this talk.

BIOGRAPHY

Dr. Tondra has been actively involved in the development of low magnetic field sensors and magnetoresistive materials at Nonvolatile Electronics (NVE) since he joined the company in 1996. He is currently managing programs for the development of Spin Dependent Tunneling magnetic field sensors and Spin Transistors. Work in connection with these programs include device design, planning experiments, and the testing and charact- erization of magnetoresistive materials. He also coordinates the efforts of projects having low field sensing applications. He received a Ph.D. degree in 1996 from the University of Minnesota in solid state physics under the guidance of Prof. E. Dan Dahlberg. His research there focused on the magnetotransport properties of thin films, including AMR, GMR, and the extraordinary hall effect. He received a B.S. in physics and mathematics, with honors, from the University of Wisconsin-Madison in 1989. He lives in Minneapolis with his wife Katharine and 16 month old son Daniel.

For more information on the seminars, please call Jack Judy at 612/625-7381 or email at judy@ece.umn.edu