On the 1/f noise of triple-gate field-effect transistors with high-k gate dielectric

Abstract

The low-frequency noise of triple-gate fin field-effect transistors (finFETs) fabricated on silicon-on-insulator (SOI) substrates, with HfO2 or HfSiON gate stacks has been studied. In most cases, 1/fγ noise has been observed with γ<1 for low frequencies f. It is shown that this type of noise can be ascribed to number fluctuations and scales with the effective device area. Based on a simple tunneling model, the noise spectral density has been converted to an oxide trap density profile, exhibiting a decay in Not for larger distances from the Si–SiO2 interface. This stands in contrast with planar bulk devices with a similar high-k gate stack and seems to be typical for the fin processing used, irrespective of further process details, like the use of selective epitaxial growth, strained SOI or strain-inducing cap layers.