Dependence of hot carrier reliability and low frequency noise on channel stress in nanoscale n-channel metal-oxide-semiconductor field-effect transistors

Abstract

In this paper, the dependence of low-frequency (LF) noise, such as 1/f noise and random telegraph signal (RTS) noise, and the hot carrier reliability in n-channel metal-oxide-semiconductor field-effect transistors (NMOSFETs) on channel stress has been studied. The normalized noise power spectral density (S/D//D2) and RTS amplitude of NMOSFETs with compressive channel stress are greater than those with tensile channel stress because the active traps contributing to RTS noise with compressive stress are distributed closer to the Si/SiO2 interface. LF noise characteristics, as well as device performance are enhanced by introducing tensile channel stress to nanoscale NMOSFETs. However, it is shown that device degradation caused by tensile channel stress is greater than that caused by compressive channel stress under channel hot carrier (CHC) and drain avalanche hot carrier (DAHC) stress conditions. Therefore, concurrent consideration of reliability and LF noise characteristics as well as dc device performance is necessary in channel strain engineering for next generation complementary metal-oxide-semiconductor fieldeffect transistors (CMOSFETs) especially for analog or mixed signal integrated circuit applications. © 2011 The Japan Society of Applied Physics.