Radant MEMS President discusses RF switches
MEMS based switches for RF applications are the basic block for more complex RF MEMS architectures. We recently spoke with Dr. Jean-Claude Sureau, President of Radant MEMS.
MEMS Investor Journal: Your main products are RF MEMS switches. Could you please describe how RF MEMS switching works in general?
Dr. Jean-Claude Sureau: RF MEMS switches are electrostatically-actuated mechanical switches with dimensions of the order of 100 microns. They are contained in hermetically-sealed packages resulting in discrete devices or higher level assemblies of the order of less than 2mm in size. They use either a cantilever beam or a membrane and the contact is metal to metal or capacitive. RMI’s technology involves cantilever beams and metal-to-metal contact.
MEMS Investor Journal: What are the alternative approaches that are currently used for switching in electronics?
Dr. Jean-Claude Sureau: Many microwave control components currently use FET or PIN diodes and, to a lesser extent, ferrite materials. These technologies introduce either a significant RF loss or require high control energy or both.
MEMS Investor Journal: For which applications is RF MEMS approach most advantageous? For which applications is RF MEMS switching not desirable?
Dr. Jean-Claude Sureau: The use of RF MEMS switches is particularly attractive for applications in which energy savings, (either RF or DC control) and small footprint are at a premium. Compared to some of the alternatives, they are intrinsically more limited in terms of their high power handling capability although we are working on mitigating this problem.
MEMS Investor Journal: Is RF MEMS switching used in any commercialized products today? Which products?
Dr. Jean-Claude Sureau: We are not aware of any significant use of RF MEMS switches in commercialized products.
MEMS Investor Journal: Which applications are likely to adopt RF MEMS switching technology in the near future?
Dr. Jean-Claude Sureau: Military applications, across their full range, because they tend to be particularly performance sensitive, are likely to be an avenue for incorporation into products. At the other end of the spectrum, there appears to be a lot of interest for cell phone applications.
MEMS Investor Journal: What have been the main challenges in developing your RF MEMS switching products?
Dr. Jean-Claude Sureau: The main challenges have been two-fold but related. On one hand, improving the device reliability has been the focus of our development and RMI has been able to demonstrate, as independently validated by several DoD laboratories, several hundred billion cycles of operating life. On the other hand, we have had to undo the damage done in the eyes of potential customers as a result of previous failures of other organizations.
MEMS Investor Journal: Companies have been developing other RF MEMS components. Besides switches, what RF MEMS component do you think is currently closest to mass deployment?
Dr. Jean-Claude Sureau: Elemental switches will remain the basic building block. If one talks about “mass deployment”, then cell phones is the first likely such application. However, the DoD market in the form of higher level assemblies such as phase shifters , tunable filters, frequency control, i.e. the traditional components found in military applications is likely to be the first significant, albeit not “mass deployment” outlet for this technology. At least that is the market on which RMI is focusing.
***********************
Dr. Sureau is the President and CEO of Radant MEMS, Inc. Under his leadership Radant MEMS was founded. He has more than 43 years of experience in technology and defense industries.
In addition, Dr. Sureau has been CEO and president of Radant Technologies Inc. since 1981, during which time Radant Technologies has become a leading manufacturer of advanced Radomes and related electromagnetic devices. Prior to that, Dr. Sureau held leading senior scientific positions at a number of companies including MIT Lincoln Laboratory, Grumman Aerospace, and Wheeler Laboratories/Bell Telephone
Dr. Sureau is the author of the chapter on "Microwave beacon Antennas" in the second edition of the Antenna Engineering Handbook, (R.C. Johnson, Editor) and contributed to "Significant Phased Array Papers" (R. C. Hansen, Editor) and "Phased Array Antennas" (Oliner and Knittel, Editors).
Dr. Sureau received his formal education at the Polytechnic Institute of Brooklyn from which he holds a BS, MS, and Ph.D. in Electromagnetics.

Please Dr. Jean-Claude Sureau , i need your help for RF MEMS Switch , i`m working in Master degree in RF MEMS applications and need some data about MEMS switch, Values of capacitors on and off, and how can i bye it from internet , and some about MEMS and varactor.
Thanks Alot
Posted by: A.Fawzy Daw | October 08, 2007 at 04:14 PM