An Experimentally Verified Temperature Dependent Drain Current Fluctuation Model for Low Temperature Applications

Abstract

In this work, an accurate temperature-dependent drain current $I_{\mathrm { D}}$ fluctuation model valid from 10 to 300 K was proposed for 18 nm ultra-thin body and buried oxide (UTBB) n-channel field effect transistors (n-FETs). The temperature dependence of $I_{\mathrm { D}}$ fluctuation was characterized and investigated from 300 K down to 10 K. In moderate inversion mode, $I_{\mathrm { D}}$ fluctuation is more severe at sub-100 K while in the strong inversion mode, it still can be overshadowed by the charge screening effect. Cryogenic virtual source (CVS) device model was used to extract and analyze the carrier density and mobility which are used in the current fluctuation model. The current fluctuation model was experimentally verified under different inversion conditions, showing it can be used to analyze and optimize the flicker noise in the low temperature (LT) circuit applications.

Keywords

• Drain current fluctuation
• low temperature
• UTBB n-FET
• scattering mechanism
• virtual-source model