Semiconductor devices, such as field effect transistors (FET's), are familiar building blocks of integrated circuits formed in silicon substrates. A single silicon-based integrated circuit may feature many thousands to millions of FET's, along with other passive components such as resistors and capacitors. However, silicon based technologies face certain limitations. Limitations on silicon wafer size limit use in large area electronics. The high temperature processing required during silicon device processing prevents the use of low-cost substrates, such as plastics, and limits the application of advanced fabrication technologies, such as roll-to-roll processing. Silicon-based electronics are difficult to integrate seamlessly with chemical/biological components. A full extension to three-dimensional device structures is unlikely with silicon-based technologies. Silicon device structures are fundamentally planar and are therefore difficult, if not impossible, to adapt to non-planar surfaces.
Various nontraditional alternatives have been proposed to conventional silicon technologies. One alternative, quantum computing, has limited applications and has encountered manufacturing difficulties. Another alternative, DNA computing, is time consuming and suffers from imprecise operation. Yet another alternative, microfluidic computing, has found only limited applications. Still another alternative, organic electronics, offers limited performance, lifetime and reliability.
What is needed, therefore, is a switching scheme for device fabrication that does not suffer from the limitations of conventional silicon-based device technologies and the limitations of proposed alternatives to silicon-based device technologies.