Northrop Grumman Microsystems Seminar: Robert Howell, "SLCFET and RF Switch Device Technology"
Thursday, October 12, 2017
1146 AV Williams Building
Super-Lattice Castellated Field Effect Transistors (SLCFET) and the State of the Art in RF Switch Device Technology
Enterprise Technologist for RF Components
Mission Systems Sector
Northrop Grumman Corp.
Within most RF systems, a chain of semiconductor devices is used to amplify and condition or steer the RF energy within those systems. But while significant progress has been made over the past several decades in building higher performance semiconductor based amplifiers, little corresponding improvement has been made over that time to the basic element of the RF chain that conditions and steers the RF energy around RF MMICs and circuits, the RF switch. Yet the performance of the RF switch in future RF systems is growing in importance with the advent of higher frequency, broadband and multifunction systems, where the defects of the lower performance state of practice semiconductor switches begin to dominate the resulting system performance. Technologies such as RF MEMS and PiN diodes have long been suggested as options for use as high performance RF switches, but reliability, switching speed, ease of design and integration, power handing and power dissipation issues have severely limited the utility of those technologies. The ‘holy grail’ of RF switch technologies has been to create an RF switch that performs as well as RF MEMS or PiN diodes from a loss, frequency and isolation perspective, but with all the positive aspects of a semiconductor field effect transistor as well, such as high speed switching, low power dissipation and an ease in integration into a larger MMIC. This seminar covers the underlying mechanisms that dictate the performance of RF switches, and describes the novel, three dimensional semiconductor device topology developed at NGMS, the Super-Lattice Castellated Field Effect Transistor (SLCFET), which provides a solution to this 30+ year old problem within the field of semiconductor device research and development.
Robert Howell graduated with a B.S. in engineering and a B.A. in history from Swarthmore College in 1995, and completed his Ph.D. in Electrical Engineering at Lehigh University in 2000. He has worked at Northrop Grumman for the past 16 years outside of Baltimore Maryland, currently as part of the Mission Systems Sector. He has been performing and leading research and development activities into semiconductor devices and processes in a wide variety of material systems, including SiC, GaN, GaAs, Si and GeTe, and device types, such as DMOSFETs, SITs, HBTs, HEMTs, and most recently the SLCFET. He is an NG Fellow, and is currently the Senior Technologist for RF Systems in the Advanced Concepts and Technology Division within Mission Systems. He has co-authored over 50 publications, and holds 14 patents.