Statistical modeling method for radiofrequency variable capacitor

Abstract

The invention discloses a statistical modeling method for a radiofrequency variable capacitor. The statistical modeling method comprises the following steps: determining all model parameters needing to be extracted for device modeling; classifying the parameters; performing a scattering parameter test on a device, and establishing a reference model not including process fluctuation of the device; acquiring the fluctuation characteristic of the scattering parameter of the device on a whole wafer, and determining a fluctuation data part; constructing an index for performing statistical modeling on the device based on the scattering parameter of the fluctuation data part and a network parameter converted from the scattering parameter; calculating each element value in a sub-circuit model based on the index, performing sensitivity analysis and sequencing of the element values relative to an index value, and selecting an element with highest sensitivity; performing sensitivity analysis and sequencing of parameter values relative to the element values respectively specific to each type of parameter groups in an element extension formula; selecting a parameter with highest sensitivity, and fitting the statistical characteristic distribution of the device to obtain a statistical model of overall fluctuation distribution of the device. The modeling process is rapid and clear.

Description

technical field [0001] The invention relates to the technical field of semiconductor device modeling technology, in particular to a statistical modeling method for a radio frequency variable capacitor. Background technique [0002] Varactor (Varactor), as the main capacitance adjustment device, plays a very important role in the design of radio frequency integrated circuits. As the process node decreases, its performance fluctuation caused by the process on the entire wafer becomes more and more significant. At present, there is no public report on the modeling of the statistical characteristics of the radio frequency performance of the varactor. [0003] The radio frequency modeling method of the varactor has not formed a unified standard, which means that the model can adopt different sub-circuit structures, and the components in the circuit can also adopt different scalability (Scalable) formulas. Most of the formulas do not have strict physical meaning, but are based on...

AI Technical Summary

Problems solved by technology

Most of the formulas do not have strict physical meaning, but are based on mathematical fitting, resulting in model parameters that cannot accurately correspond to device manufacturing process parameters

This makes it difficult to select statistical model parameters for characterizing process fluctuations

[0004] For the processes of different foundries, the reasons for the process fluctuations are different, that is, different statistical distribution characteristics are shown in the test data, and it is difficult to select a unified and fixed standard index for statistical modeling of the varactor

Images