用于低功耗、混合信号及高频领域的CMOS技术的缩比进展，表明其最佳的高频性能已从低中反区转移至弱反区。高频噪声模型是射频与毫米波电路设计的先决条件，是纳米级金属氧化物半导体场效应晶体管(MOSFET)噪声分析的重要基础。本文基于40 nm MOSFET的器件物理结构，并结合漂移-扩散方程和电荷守恒定律，提出了基于物理的高频感应栅极电流噪声模型及其与漏极电流噪声的互相关噪声模型，以此来统一表征噪声从弱反区到强反区的频率与偏置依赖性。本文通过将有效栅极过载引入高频噪声模型中，使得统一模型具有良好的准确性、连续性和平滑性。最后，通过所建模型的仿真结果与实验结果的数据比较，验证了本文所建模型的准确性及其对长沟道器件在强反区的适用性。%With the development of down-scaling of CMOS technology for low power, mixed-signal, and high frequency ap-plications, the optimal high frequency performance is shown to be shifted from lower moderate inversion toward weak inversion regimes. High-frequency noise model is a prerequisite for designing the radio frequency and millimeter-wave circuits, and is essential for the noise analysis of nanoscale metal-oxide-semiconductor field-effect transistors (MOSFETs). In this paper, based on the physical structure of 40 nm MOSFET and by considering the drift-diffusion equation and charge conservation law, accurate physics-based unified high-frequency noise model is developed for induced gatecurrent noise and its cross-correlation with drain-current noise under different bias conditions, which is used to describe the fre-quency and bias dependence of 40 nm MOSFET from weak inversion to strong inversion regime. Especially, the effective gate overdrive is explicitly included in unified noise model to offer excellent accuracy, continuity and smoothness, and this makes the proposed analytical models convenient to directly reflect the relationship between the noise model and bias condition. Besides, new analytical model is derived for the induced-gate current noise and its cross-correlation term of weakly inverted MOSFET. These simple expressions not only serve as the asymptotic limit for the validation of the proposed physics-based unified model, but also provide a clearer insight into and better understanding of the gate noise behavior and their cross-correlation in the weak-inversion region. Moreover, in terms of the proposed subthreshold noise model, the charge of weak inversion rather than the normal effective channel thickness approximation is involved. In this way, the model accuracy can be improved. Furthermore, a detailed derivation and discussion are presented by analyzing the physics-based noise generation mechanism of transistor including the channel thermal noise and the shot noise based on the small-signal equivalent circuit of the 40 nm MOSFET device. Using these expressions it is possible to extract the values of all the noise model parameters directly from measurement. The proposed model is demonstrated by using noise data from both measurement and the noise simulation. Excellent agreement between simulated and measured noise data shows that the proposed model can be used for predicting the noise behavior of 40 nm MOSFET under different dimensions and operating conditions. The applicability of reported model for drain-current noise is also verified. As far as small-signal (i.e., linear) bias-dependent operation is concerned, it is shown how most of the findings of this work can also be used to predict the data of long channel devices in the strong-inversion regimes.
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