Reliability aspects of the low-frequency noise behaviour of submicron CMOS technologies

Abstract

This overview concentrates on reliability aspects of low-frequency (LF) noise in present-day CMOS technologies and transistors. It focuses on how different degradation mechanisms affect the LF noise behaviour and discusses the impact of technological modifications intended to enhance the lifetime of components and circuits. Whenever possible, the physical background will be highlighted, although for a detailed treatment dedicated reviews have to be consulted. The paper consists of two main parts. One covers the degradation mechanisms on a transistor level, including the impact of homogeneous and hot-carrier degradation and the effect of back-end processing steps and, more specifically, plasma damage on the LF noise. In the second part, the noise aspects of the metal interconnect lines related to the occurrence of electromigration are summarized. Because of the downscaling of technologies this aspect gains more and more weight and is, at the same time, a vital part of modern CMOS technology. Throughout the presentation, the possibilities of using noise as a lifetime-predictive tool are discussed and illustrated.

Different mechanism to explain the 1∕f noise in n- and p-SOI-MOS transistors fabricated on (110) and (100) silicon-oriented wafers

“…12,13 As a consequence, the quality of processes involved in the fabrication of the gate insulator can be characterized by the evaluation of the low frequency noise. [14][15][16] Some are explaining the 1 / f noise through a bulk phenomenon induced by the fluctuation of mobility in the lattice, 17 first introduced during the 1970s by Hooge and generally noted ⌬, while others are attributing it to a fluctuation in the number of carriers caused by interface traps, 18,19 this model is the McWhorter one, generally abbreviated ⌬N. The latter, a third theory, first suggested by Mikoshiba 20 and abbreviated ⌬N-⌬, has been developed by several authors and involves the correlation between the number and mobility fluctuations.…”

Effect of gate leakage current on noise properties of AlGaN/GaN field effect transistors

“…One of the possible reasons for this phenomenon is a nonstationary behavior of the gate current, demonstrated for Si metal-oxide-semiconductor field effect transistors. 11 Hence, we conclude that in these HFETs, the fluctuations of the gate leakage current do significantly contribute to the output noise.…”

Noise and reliability in simulated thin metal films

“…Electromigration poses many challenges to materials science and technology, as many aspects remain unclear and hence reliability estimations are often made on the basis of a phenomenological approach. The physics of electromigration has been extensively studied, from the atom transport mechanism, to interface and grain boundary aspects, to the mechanical aspects of passivated structures [1][2][3][4].…”

“…Another group of studies has focused on the statistical properties of the typical 1/f 2 noise [2,3,11,12] associated to electromigration. Since this type of noise is generated during the onset of the damage and of the subsequent current path changes, it is reasonable to conjecture that it could provide useful information even in the early stages of electromigration.…”