Direct White Noise Characterization of Short-Channel MOSFETs (original) (raw)

Improved analysis and modeling of low-frequency noise in nanoscale MOSFETs

Solid-State Electronics, 2012

Extensive investigation of the low-frequency noise in n-channel and p-channel MOSFETs, with high-k gate stack and channel length varying from 1.8 lm down to 26.4 nm, has been carried out. The results demonstrate that the carrier number fluctuation with correlated mobility fluctuations describes accurately and continuously the 1/f noise for all operation regions, i.e. from weak to strong inversion and from linear to saturation. It has been found that the product of the Coulomb scattering coefficient and the effective carrier mobility a sc l eff is constant over a wide range of the drain current due to the interplay of the Coulomb scattering coefficient a sc and the effective carrier mobility l eff variations. In addition, a non-linear increase in the square root of the input gate voltage noise with the gate voltage overdrive was observed explained by the surface roughness scattering. The overall results lead to an analytical expression for the 1/f noise model, enabling to predict the noise level of a transistor with any channel dimensions using its transfer characteristic. This finding makes the noise model suitable for circuit simulation tools.

Thermal noise modeling for short-channel MOSFETs

IEEE Transactions on Electron Devices, 1996

Abshzc&-An analytical formulation of the thermal noise in shiort-channel MOSFET's, working in the saturation region, is presented. For the noise calculation, we took into account effects like the field dependent noise temperature and mobility, thle device geometry and the channel length modulation, the back gate effect and the velocity saturation. The derived data from the model are in good agreement with reported thermal noise measurements, regarding the noise bias dependence, for transistors with channel lengths shorter than 1 pm. Since the present thermal noise models of MOS transistors are valid for channel lengths well above 1 pm, the proposed model can be easily incorporated in circuit simulators like SPICE, providing an extension to the analytical thermal noise modeling suitable for submicron MOSFET's.

High-frequency noise measurements on MOSFETs with channel-lengths in sub-100 nm regime

2009 2nd International Workshop on Electron Devices and Semiconductor Technology, 2009

High-Frequency signal and noise measurements on 40 nm , 80 nm , and 110 nm , gate-length MOS transistors are performed. On-wafer measurements of S-parameters up to 18 GHz yield an accurate small-signal RF device model with m g in excess of 1000 mS/mm. Noise contributions due to gate resistance, substrate resistance, source and drain resistances, substrate current and induced-gate noise are found to be small in comparison with total observed noise. The noise parameter γ is bias dependent and increases as channel-length decreases. The observed values are well above the ideal value of 2/3 consistent with previously published results. Index Terms-HF excess channel noise, nanoscale MOSFET, NF 50 , RF CMOS.

Extraction of the channel thermal noise in MOSFETs

ICMTS 2000. Proceedings of the 2000 International Conference on Microelectronic Test Structures (Cat. No.00CH37095)

An extraction method to obtain the channcl thcrmal noise in MOSFETs directly from DC, scattering paramctcr and RF noise nieasurements is presentcd, In this extraction mcthod, the transconductance (g,,J, output resistancc (RDs), and source and drain resistances (Rs and RD) are obtained from DC measuremcnts. The gate resistancc (RG) is extracted from s c~t t c i. i n~-p~r~m e t~r mcasurcmcnts, and thc cquivalcnt noise resistance (RJ is obtained from RF noise measuremcnts. This mediad has bccn verified by using the measured data of a 0.36 pin n-typc MOSFET up to 18 GHz. INTHODUCTION With the very high unity-gain frequencics (f~) of deep sub-micron MOSFETs of more than 100 GHz, many highspeed or radio-frcqucncy (HI?) integratcd circuits (ICs) which were fabricntcd cxclusively in IILV or bipolar technologics are likely to bc implcmcnted in CMOS tcchnology becausc of its low cost and high levcls of integration [I ,2]. However, when working at high frequencics with sub-micron dcviccs, the noise gcncrated within the dcvicc itself will play an increasingly important mol e in the ovcrall noise pei-formancc of analog circuits. Thcrcfore, an accuratc noisc model for die channel thermal noisc in MOSFETs is crucial for the design and simulation nf RF CMOS circuits.

Thermal Noise in MOSFETs: A Two or a Three-Parameter Noise Model

IEEE Transactions on Electron Devices, 2010

In this brief, it is clearly demonstrated that a twoparameter noise model is sufficient to accurately extract the MOSFET high-frequency noise performance, as long as channel uniformity is ensured (which corresponds to mainstream CMOS technology). Nevertheless, in the case of asymmetric channelbased MOSFETs, it is shown that a three-parameter noise model is required.

Semi-classical noise investigation for sub-40nm metal-oxide-semiconductor field-effect transistors

AIP Advances, 2015

Device white noise levels in short channel Metal-Oxide-Semiconductor Field-Effect Transistors (MOSFETs) dictate the performance and reliability of high-frequency circuits ranging from high-speed microprocessors to Low-Noise Amplifiers (LNAs) and microwave circuits. Recent experimental noise measurements with very short devices demonstrate the existence of suppressed shot noise, contrary to the predictions of classical channel thermal noise models. In this work we show that, as the dimensions continue to shrink, shot noise has to be considered when the channel resistance becomes comparable to the barrier resistance at the source-channel junction. By adopting a semi-classical approach and taking retrospectively into account transport, short-channel and quantum effects, we investigate the partitioning between shot and thermal noise, and formulate a predictive model that describes the noise characteristics of modern devices.

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

IEEE Transactions on Electron Devices, 2006

Compact modeling of the most important highfrequency (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.

A microscopic interpretation of the RF noise performance of fabricated FDSOI MOSFETs

IEEE Transactions on Electron Devices, 2006

In this paper, a detailed research of the high-frequency noise sources and figures of merit (FOMs) of fabricated deep-submicrometer n-channel fully depleted silicon-on-insulator MOSFETs is carried out. Special care is given to reproduce the main topology parameters, together with the most relevant parasitic elements of real devices in order to accomplish an accurate and reliable simulation. The information provided by the Monte Carlo (MC) tool allows getting a physical insight of the relationship between internal quantities and the main noise sources inside the device; moreover, the spectral density of velocity fluctuations has been analyzed spatially in order to determine the local current noise source in the gradual channel and velocity overshoot sections of the effective channel. Together with the calculation of intrinsic noise sources, the MC simulator is able to reproduce the measurements for the main noise FOMs in the RF and microwave frequency ranges. Moreover, the whole simulation framework allows addressing the importance of parasitic elements in the final value of these FOMs.

Physical origin of the excess thermal noise in short channel MOSFETs

IEEE Electron Device Letters, 2000

The physical origin of the excess thermal noise in short channel MOSFETs is explained based on numerical noise simulation. The impedance field representation and extraction method demonstrate that the drain current noise is dominated by source side contributions. Analysis identifies local ac channel resistance variations as the primary controlling factor. The nonlocal nature of velocity results in a smaller derivative of the velocity with respect to the field which in turn causes a higher local ac resistance near the source junction.