Dynamic Biasing for Improved On-Orbit Total-Dose Lifetimes of Commercial
Electronic Devices
Abstract
The survivability of microelectronic devices in ionizing radiation
environments drives spacecraft design, capability, mission scope, and
cost. This work exploits the periodic nature of many space radiation
environments to extend device lifetimes without additional shielding or
modifications to the semiconductor architecture. We propose a technique
for improving component lifetimes through reduced total-dose
accumulation by modulating device bias during periods of intense
irradiation. Simulation of this “dynamic biasing” technique applied to
single-transistor devices in a typical low-Earth orbit results in an
increase of component life from 114 days to 477 days (318% improvement)
at the expense of 5% down time (95% duty cycle). The biasing technique
is also experimentally demonstrated using gamma radiation to study three
commercial devices spanning a range of integrated circuit complexity in
109 rad/min and 256 rad/min dose rate conditions. The demonstrated
improvements in device lifetimes using the proposed dynamic biasing
technique lays a foundation for more effective use of modern
microelectronics for space applications. Analogous to the role real-time
temperature monitoring plays in maximizing modern processor performance,
the proposed dynamic biasing technique is a means of intelligently
responding to the radiation environment and capable of becoming an
integral tool in optimizing component lifetimes in space.