Noise Performance Of MOSFETs Research Articles

High-Frequency Noise of Modern MOSFETs: Compact Modeling and Measurement Issues

Compact modeling of the most important high-frequency (HF) noise sources of the MOSFET is presented in this paper, along with challenges in noise measurement and deembedding of future CMOS technologies. Several channel thermal noise models are reviewed and their ability to predict the channel noise of extremely small devices is discussed. The impact of technology scaling on noise performance of MOSFETs is also investigated by means of analytical expressions. It is shown that the gate tunneling current has a significant impact on MOSFETs noise parameters, especially at lower frequencies. Limitations of some commonly used noise models in predicting the HF noise parameters of modern MOSFETs are addressed and methods to alleviate some of the limitations are discussed

1/ f noise performance of MOSFETs with HfO 2 and metal gate on Ge-on-insulator substrates

The low frequency (1/ f) noise performance of n- and p-MOSFETs with HfO 2 and TiN–TaN metal gate on GeOI substrates has been investigated. The LF noise spectra are of the 1/ f γ type, with γ>1. The current noise spectral density is typically one decade higher than for silicon counterparts. The behavior of the noise characteristics points to carrier trapping as the prevailing 1/ f noise mechanism. Using a tunneling coefficient α=6.5×10 7 cm −1 for the Ge/HfO 2 system, the extracted volume and surface trap densities are in the range of 1×10 20/cm 3 eV and a few 10 12/cm 2 , respectively. This is of the same order as the interface trap densities, obtained from charge pumping. It is believed that the Ge/interfacial layer (IL) quality could be responsible for the significantly higher trap densities and noise, compared with Si/HfO 2/ TiN–TaN MOSFETs.

Effect of coplanar probe pad design on noise figuresof 0.35µm MOSFETs

The effects of different coplanar ground-signal-ground (GSG) probe pads on the noise figure characteristics of submicron MOSFETs are presented. Devices with top-level metal as probe pads shielded by grounded bottom-level metal possess the most appropriate probe pad structure for characterising the noise performance of MOSFETs. Equivalent circuits of the probe pads are used to explain the different noise behaviours.

An accurate and efficient high frequency noise simulation technique for deep submicron MOSFETs

Based on an active transmission line concept and two-dimensional (2-D) device simulations, an accurate and computationally efficient simulation technique for high frequency noise performance of MOSFETs is demonstrated. Using a Langevin stochastic source term model and small-signal equivalent circuit of the MOSFET, three intrinsic noise parameters (/spl gamma/, /spl delta/, and c) for the drain noise and induced gate noise are calculated. Validity and error analysis for the simulation are discussed by comparing the simulation results with theoretical results as well as measured data.