A PROPOSAL OF NANOSCALE DEVICES BASED ON ATOM MOLECULE SWITCHING

This paper proposes a very small switching device, called an atom relay, which would supersede present metal-oxide-semiconductor devices for the next decade. The basic configuration of an atom relay consists of an atom wire, a switching atom, and a switching gate, with total dimensions below 10 nm, and an operation speed at more than terahertz level. The operation principle of the atom relay is that a switching atom is displaced from the atom wire by the electric field supplied from the switching gate, and the atom relay exhibits an ''off'' state. The switching characteristics of the atom relay are demonstrated by simulation, and it is shown that the electron propagation is successfully cut if a gap of about 0.4 nm is formed in the atom wire by the displacement of the switching atom. A self-relay structure, in which the switching atom is displaced by the electric field from the atom wire itself, enables a dynamic memory cell, and the functions are ascertained by simulation. Fundamental logic circuits as NAND and NOR gate constitutions are also proposed. These logic and memory circuits can integrate a supercomputer in a 200-mum-square of area, with 10(7) gates of logic circuit and 10(9) bits of memory, and operate at more than 10(12) Hz. The atom relay is evaluated on the basis of the characteristics necessary for integrated circuit devices, together with several nanoscale devices, and is found to be the most promising candidate device for future integrated circuits.