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5. Three Terminal MOS VG Control and VCB Control

# 6. Four Terminal MOS¶

## 6.1. Notes¶

2. Read the python quick tutorial for a couple of hours to get a feel of the language. Read code samples from what you have been using. I will address issues as they come up.

## 6.2. Mid-term Project:¶

1. (2/26) Write a program that calculates Ids and internal distribution of potential and charges for a given MOSFET structure and a set of biases.

Use the simplified equations in the book.

First, set your bias above flat band to avoid the numerical issue with taking difference of two close numbers.

You can use either Matlab or Python.

You should use the QC (QS) expression in our text, which is also in our notes - it says which equation is the simplified expression in our text.

It is much easier to solve.

In fact, you have already solved for ps0 and psL before, when you did VCB sweep. ps0 and psL are simply the ps at VCB=VSB and VDB. So you can always test your code against those curves.

You can start by modifying the codes in equisemi.py, then try to reduce the codes to do only what you need to do. For instance I had lots of functions (methods) in Nmos class designed for other purposes.

You will also learn from the process how to do object oriented programming.

By all means, feel free to do it in Matlab.

2. (2/28) Once you function is working for a single bias point, generated Id-Vd curves for different VGS, and ID-VG curves for different VDS.

Use both linear and log scales for IDS. They are both meaningful in their own right.