Analyzing substrate noise for an n-channel MOSFET (NMOS) substrate has been developed using various concepts such as virtual separation concept, p-contact to p-contact model and transistor switching noise model. A design is necessary for the substrate design development to minimize noise in FoMs (Figure Of Merits) and reduce threshold voltage developed noise. In the proposed model, a substrate-induced chip used for finding the noise in drain current has been improved with the increased doping density of an NMOS device. From a substrate noise coupling network with the proposed low signal equivalent circuit, the system measures noise at NMOS substrate using a hot carrier injection model. The proposed concept has been implemented in TCAD-SILVACO software, the design was made in ATHENA, and its corresponding electrical characteristics are simulated by the ATLAS software tool. This model extracts parameters such as overall noise in FoMs, drain current-gate current bias analysis, cross-correlation, and minimized threshold value. After capacitive coupling is achieved over different operation conditions and dimensions, excellent output is from simulated noise data. 

Substrate Noise Evaluation for Lightly Doped 45nm N-MOSFET Using Physical Simulation Models

Halo implanted MOSFETs exhibit anomalous behavior in drain current power spectral density ( S ID ) of flicker noise (1/f) with the variation in drain voltage, but this behavior cannot be captured by existing 1/f models. To identify the reasons for this abnormal behavior of 1/f noise, we have performed experimentally calibrated technology computer-aided design (TCAD) simulations. We find that this anomalous behavior comes from the drain-side halo region, and it has complex dependence on the bias and geometry. We propose a sub-circuit model for 1 / f noise that successfully captures the anomalous behavior of S ID with the drain bias. This model calculates the individual contributions and the impact of different device regions, such as the source side halo, channel, and drain side halo, on the overall noise of the device. The proposed model is in good agreement with the experimentally calibrated TCAD simulations for different geometries, biases, and temperatures. The proposed model is also validated with the measurement data.

Milos Skalsky

Papers

Analysis and modeling of anomalous flicker noise in long channel halo MOSFETs