Jongwook Jeon

Temporal Noise Analysis and Reduction Method in CMOS Image Sensor Readout Circuit

Temporal noise such as thermal and low-frequency noise (LF noise) in the CMOS imager readout circuit has been analyzed. In addition, the effect of correlated double sampling operation on the noise was included. We have derived an analytical noise equation for the specified readout circuit, and confirmed its validity by comparing it with the simulation result. Thermal noise model which is accurate in short-channel devices operating in saturation region was used. Since the in-pixel devices (source follower and selection transistor) of the readout circuit are relatively small in size, and thus exhibits random telegraph signal (RTS) noise, both 1/f and RTS noise were considered for their LF noise. Based on the analyzed noise components, we presented the noise reduction method by adjusting the transistors sizes in the readout circuit.

Analytical Noise Parameter Model of Short-Channel RF MOSFETs

In this paper, a simple and improved noise parameter model of RF MOSFETs is developed and verified. Based on the analytical model of channel thermal noise, closed form expressions for four noise parameters are developed from proposed equivalent small signal circuit. The modeling results show a excellent agreement with the measured data of 0.13㎛ CMOS devices.

A New Noise Parameter Model of Short-Channel MOSFETs

In this paper, a closed form expression for noise parameters of MOSFETs are derived from a more accurate small-signal equivalent circuit. The modeling results show a good agreement with the measured data. Based on the analysis of the noise coming from channel thermal noise and parasitic resistances, the noise contribution from each component is analyzed.

Analytical thermal noise model suitable for circuit design using short-channel MOSFETs

The paper proposes a new analytical noise model for short-channel MOSFETs which covers both the linear and the saturation regions. Both the channel thermal noise model and the gate-induced model are presented. The analytical equations for the noise parameters are also derived. Modeling results show an excellent agreement with measured noise parameter data.

On the Characteristics and Spatial Dependence of Channel Thermal Noise in Nanoscale Metal–Oixde–Semiconductor Field Effect Transistors

The physical origin of the channel thermal noise in nanoscale RF metal–oxide–semiconductor field effect transistors (MOSFETs) is characterized based on an analytical noise model, which takes into account velocity saturation, channel length modulation, and carrier heating effect. These short channel effects increase the channel thermal noise compared with predicted noise from long-channel theory. Among the three effects, the channel length modulation is found to be the most important short channel effect on the channel thermal noise modeling. In addition, spatial distribution of the channel thermal noise is analyzed by using impedance field method. From this analysis, it is identified that the channel thermal noise is dominated by source side noise contributions.

Deembedding Accuracy for Device Scale and Interconnection Line Parasitics

In this letter, we investigate the deembedding accuracy of open-short (OS) and pad-open-short (POS) deembedding for transistor measurement and modeling. It is found that all of the transistor intrinsic element values except for the gate-resistance, Rg , are independent of the deembedding procedure. Furthermore, the difference in Rg is dependent on the device size. To analyze the origin of the deembedding difference, the equivalent circuits of the PADs and interconnection lines are constructed from the measured data by varying the values of parasitic parameters.

White noise characteristics of nanoscale MOSFETs in all operating regions

In this paper, the white noise characteristics of nanoscale MOSFETs are presented in all operation regions. The measured drain current noise data are compared with power spectral density of shot-like and thermal noise models. The experimental results show that drain current noise is shot-like in weak inversion region and thermal noise in strong inversion region even at 36 nm gate length.

Noise in nano-scale MOSFETs and flash cells

In this paper, we present a compact channel thermal noise model for short-channel MOSFETs which takes into account various short channel effects. Then, we compared measured data with shot-like noise level and thermal noise model in sub-40 nm CMOS devices. Also we characterized four level RTN (Random Telegraph Noise) and extracted the characteristics of two independent traps in MOSFETs and flash cells. Their vertical, lateral locations in the oxide as well as the trap energy (ET) were obtained by using accurate equations.