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Functional robustness is one of the primary challenges for embedded memories as voltage levels are scaled below 1 V. A low-power high-speed tunneling SRAM (TSRAM) memory array including sense amplifiers and pre-charge circuit blocks operating at 0.5 V is designed and simulated using available MOSIS CMOS 90 nm product design kit coupled with VerilogA models developed from this group's Si/SiGe resonant interband tunnel diode experimental data. 1 T and 3 T- 2 tunnel diode memory cell configurations were evaluated. The memory array assigns 0.5 V as a logic “1” and 0 V as a logic “0”. Dual supply voltages of 1 and 0.5 V and dual threshold voltage design are used to ensure high sensing speed concurrently with low operating and standby power. Read access time of 1 ns and write access time of 2 ns is achieved for the 3 T memory cell. Write access time can be reduced to 0.5 ns for 32 bit write operations not requiring a preceding read operation. Standby power dissipation of 6\times 10^-5\ \ mW per cell and dynamic power dissipation of 1.8\times 10^-7\ \ mW/MHz per cell is obtained from the TSRAM memory array. This is the first report of TSRAM performance at the array level. [ABSTRACT FROM PUBLISHER]

In recent years, many advances have been made in the development of molecular scale electronics which have inspired interest in using the devices thereof for memory and logic. This paper describes the design of a logic architecture using a particular class of molecular devices. Specifically, it is shown that the feature of hysteretic switching common to many molecular devices can be utilized to build programmable arrays. Also utilized in the designs presented here are molecular devices which exhibit negative differential resistance (NDR), a property useful for providing signal restoration at the nanoscale. This work begins by describing the potential for both programmability and NDR in molecular scale electronics. These ideas are then brought together in the design of a programmable logic array based on majority logic. [ABSTRACT FROM AUTHOR]