Pulling the plug on the current drain [threshold switching]

Power management is one of the main challenges to continued development of large-scale integrated circuits. In particular, the offstate, or standby leakage, is becoming a significant fraction of total power consumption as gate dimensions continue to shrink. A review of the literature identified many possible solutions in the application of threshold-switching devices. This data has apparently never been summarized in one place, suggesting a need for this article. This article discusses the capabilities of classical amorphous semiconductor switches, and more recent advances in silicon, III-V materials, and organic semiconductors that all exhibit threshold-switching properties. Applications and future prospects for the development of more energy-efficient devices are discussed. The long-term vision is that conductors themselves can be engineered to dynamically sense and adapt their conductivity to active or passive states as required.