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This paper presents that advanced actively body-bias controlled (Advanced ABC) technology contributes to enhancing operation margins of static random access memory (SRAM). For the first time, significant enhancement of static noise margin (SNM) is successfully realized by using a body bias of load, access, and driver transistors while suppressing threshold-voltage variations. In this technology, well taps control the body potential of the load transistor and word lines also control the body potential of the access and driver transistors. It is demonstrated that the write and read margins of 65-nm-node silicon-on-insulator (SOI) SRAMs are improved by the Advanced ABC technology. Furthermore, it is found that the SNM is enhanced by 27% for 32 nm and 49% for 22 nm node. It is summarized that this technology is one of countermeasures for emerging generations.

Dynamic force spectroscopy (DFS) based on atomic force microscopy, which enables us to obtain information on the interaction potential between molecules such as antigen–antibody complexes at the single-molecule level, is a key technique for advancing molecular science and technology. However, to ensure the reliability of DFS measurement, its basic mechanism must be well understood. We examined the effect of the molecular linker used to fix the target molecule to the atomic force microscope cantilever, i.e., the force direction during measurement, for the first time, which has not been discussed until now despite its importance. The effect on the lifetime and barrier position, which can be obtained by DFS, was found to be ∼10 and ∼50%, respectively, confirming the high potential of DFS.

Reliability against radiation is an important issue in silicon on insulator metal oxide semiconductor field effect transistors (SOI MOSFETs) used in satellites and nuclear power plants and so forth which are severely exposed to radiation. Radiation-caused characteristic change related to the isolation-edge in an irradiated environment was analyzed on SOI MOSFETs. Moreover short channel effects for an irradiated environment were investigated by simulations. It was revealed that the leakage current which was observed in local oxidation of silicon (LOCOS) isolated SOI MOSFETs was successfully suppressed by using field shield isolation. Simulated potential indicated that the potential rise at the LOCOS edge can not be seen in the case of field shield isolation edge which does not have physical isolation. Also it was found that the threshold voltage shift caused by radiation in short channel regime is severer than that in long channel regime. In transistors with a channel length of 0.18 µm, a potential rise of the body region by radiation-induced trapped holes can be seen in comparison with that of 1.0 µm. As a result, we must consider these effects for designing deep submicron devices used in an irradiated environment.