Due to the huge power consumption and expensive fabrication methods required, down scaling silicon devices to sub-100 nm dimensions is becoming very unattractive. On the other hand, it is easier to build electronic circuits using molecules since they are small and their properties can be tuned. In this review, we first discuss the building blocks of molecular electronics. We then describe how these building blocks can be used to build single molecule based digital logic such as AND, OR and XOR gates. The distinction of these molecular electronic building blocks is that for first time, (i) the Tour wires are used as the conductive backbone for the rectifying junctions, (ii) donor/acceptor principles are implemented in the molecular wire itself and (iii) the logic gates are realized using molecular rectifying diodes embedded in the molecular conducting wire itself.
Molecular electronics, molecular diode, molecular RTD, digital logic, AND, XOR
Department of Electrical Engineering, Indian Institute of Technology, New Delhi 110 016, India.