HALL OF FAME / inventor profile

Robert Bower
Born Jun 12 1936

Field-Effect Device with Insulated Gate; Self Aligned Gate MOSFET
Patent Number(s) 3,472,712

Inducted 1997


Robert Bower invented the Field-effect Device with Insulated Gate known as the Self-Aligned Gate MOSFET, which has created the fast, design-stable device that is the foundation of all modern integrated circuits.

Invention Impact

The MOSFET has become the basic element of all silicon integrated circuits. The basic device was conceived by Lilienfeld in the 1920’s, but he had no platform on which to build the device. The silicon planar process conceived in the late 1950’s by McCaldin and Hornoi and the Integrated circuit conceived by Kilby and Noyce was that platform that was needed to allow Lilienfeld’s device to be realized in the modern era. Hofstein and Heiman in 1963 described the nature of the MOSFET on the silicon planar process platform. However, the key to the beauty, power and simplicity of the MOSFET had yet to be found. The Self-Aligned Gate Ion Implanted MOSFET or SAGFET conceived by Bower in 1965 was the key that allowed the power of the MOSFET to be unlocked. Prior to the SAGFET the MOSFET was a relatively useless novelty compared to the Bipolar Junction Transistor (BJT) conceived by Bardeen, Schockley and Brattain. The pre self aligned gate MOSFET was very difficult to use in integrated circuit design because of the uncertainty of the placement of the gate with respect to the source and drain, and slow because of the relative size of the gate. Bower solved both of these problems by using the gate structure itself as the mask or template to define the placement of the source and drain with respect to the gate. This simple, but profound step eliminated the uncertainty of the placement of the gate which solved the integrated circuit design problem and allowed the theoretically smallest possible gate to be used in the formation of the device. Thus, the SAGFET then surpassed the BJT in the early 1970’s and has to this date, 40 years later become the device of choice used by the tens of millions in all modern integrated circuits. Indeed, the SAFGET is the most replicated man made structure in the history of mankind.



Inventor Bio

Born in Santa Monica, California, Bower joined the Air Force in 1954. He attended UC Berkeley after his service, and in 1962 earned an A.B. in Physics while working at the Lawrence Radiation Laboratory.

His work led to a Hughes Fellowship and entry to the California Institute of Technology, where in 1963 he earned an M.S. in Electrical Engineering. In 1965 he joined Hughes Research, where he conceived ways of using ion engine technology in the semiconductor field. While at Hughes, he developed the concept of the Self-Aligned Gate Transistor using ion implantation to form the Source and Drain with the gate element as the self-aligned mask.

He returned to Cal Tech to work on his Ph.D. in Applied Physics in 1973. He was a founder of Mnemonics, a company developing his invention of high density CCDs (Charge Coupled Devices) for memory applications in 1975. In 1979 he joined Advanced Micro Devices as a senior scientist and in 1986, he became an IEEE Fellow. Recently, he has pioneered work on three-dimensional microelectronics.

© 2002 National Inventors Hall of Fame