Operation of SOI CMOS devices at liquid-nitrogen temperature

Liquid-nitrogen-temperature (LNT) operation of silicon-on-insulator (SOI) CMOS devices has been investigated experimentally. The maximum carrier mobilities in these devices increase by factors from 1.25 to 4.5 between room temperature and LNT. At LNT, the increase in depletion-layer width and the resulting threshold-voltage increase are limited by the silicon film thickness. For SOI devices with a body contact, the series resistance between channel and body contact increases at lower temperature, resulting in a current kink in saturation I-V characteristics.<
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