Architectures for molecular electronic computers: 3. Design for a memory cell built from molecular electronic devices

This paper proposes and explains a design for a digital electronic memory cell that is built solely from molecular electronic devices. The molecular-scale memory cell is modeled after the much larger, micron-scale cell in solidstate nanoelectronic tunneling static random access memory (TSRAM), which has been demonstrated recently. The underlying elements concerning both molecular-scale electronic devices and microelectronic memory architecture are reviewed en route to their synthesis in the design of the molecular electronic TSRAM (i.e., METSRAM) cell. Quantitative theoretical analysis is performed on the proposed ME-TSRAM memory cell, which is a simple planar aromatic molecule measuring only 8 nm by 5 nm. Specifically, ab initio quantum mechanical calculations are performed to estimate the capacitances of the various components of the proposed memory cell. On that basis, it is concluded that if it were fabricated, the ME-TSRAM cell would be likely to function as desired. Finally, various fundamental molecular memory cell design issues and architectural challenges are enumerated and discussed. In making and analyzing these specific design proposals for molecular-scale electronic memory, this work attempts to explore the ultimate limits of electronic memory circuit miniaturization.