This is the second part of an article on molecular electronics. The first part, published in the August 2004 issue of EDFA , discussed the development of molecular devices including nanowires, rectifiers, switches, and transistors. Here, the author describes nontraditional molecular computing architectures based on crosspoint arrays, randomized nanocells, and cellular automata. Challenges associated with interconnect demand, lithography alternatives, and defect tolerance are also discussed.

This article reviews recent developments in the area of molecular-scale computing. It describes the construction and operating characteristics of molecular wires, rectifiers, switches, and transistors. It also discusses the concept of molecular gain. Molecular computing architectures based on crosspoint arrays, randomized nanocells, and cellular automata will be discussed in Part II of this article in the November 2004 issue of EDFA .