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An actively body-bias controlled (ABC) silicon-on-insulator (SOI) static random access memory (SRAM) connecting the bodies of the access and the driver transistors with the word line is proposed to realize high-speed and low-voltage operation. We developed the direct body contact to apply forward biases to the bodies without increases in the area penalty and the parasitic gate capacitance. An increase of the standby current does not occur because the body biases are not applied when the word-line voltage is low level. It is demonstrated that a significant speed improvement and a reduction of performance variations for the SRAM are achieved by applying the body bias. Neutron-accelerated soft-error tests reveal that the ABC structure suppresses soft-error events due to the body-tied SOI structure. In summary, the ABC SOI technology is one of the countermeasures for emerging generations.

This paper presents that advanced actively body-bias controlled (Advanced ABC) technology contributes to enhancing operation margins of SRAMs. Significant enhancement of static noise margin (SNM) is successfully realized by using a body bias of load transistors while suppressing threshold-voltage variations for the first time. It is demonstrated that the write and read margins of 65nm-node SOI SRAMs are improved by the advanced ABC technology. Furthermore, it is found that the SNM is enhanced by 27% for 32nm and 49% for 22nm node. It is summarized that this technology is one of countermeasures for emerging generations.

As the LSI process technology advances, increase of power consumption for the LSIs becomes major issue because of number of transistors and clock frequencies increase. For a reduction of the power consumption of the LSI, lowering supply voltage technology is one of the effective ways such as applying a dynamic threshold voltage (DT) structure as stated in J. P. Colinge (1987). However, a DT SOI MOSFET with T-shape or H-shape gates has disadvantages of area penalties and a gate parasitic capacitance increase. In this paper we describe actively body-bias controlled (ABC) SOI MOSFET technology with hybrid trench isolation (HTI) based in Y. Hirano et al. (2000). This structure doesn't need the T or H gates and realizes low-voltage and high-speed operation with controlling a body potential.