What is a MOSFET but a plain old block of silicon with some terminals printed on it. I start here with the most basic of components. Here are the relevant points:
- I want to think about N channel MOSFET so I start with P type material doped at Na=10^16 cm^-3
- Area = A = 1cm x 1cm
- Length = 429cm I chose this because mobility of Boron doping @10^16 = 429cm^2 / V*S
Line of reasoning
- Apply 1 volt
- In 1 second the carriers travel 429cm and thus all the charge in the entire block is swept out and totally replaced.
- Calculate R=V/I
- Compare with value calculated from the page below
but this is the amount of charge swept out in 1 second from the silicon bar so
Remember 1 volt was applied to get the 429cm/second carrier velocity and thus
Which agrees with the calculated value from the first web link reference below.
Research Links
- Calculate Input doping, dopant type > compute resistivity
- Resistivity, Sheet Resistance and Mobility Overview – This is a straight forward treatment that I should have read sooner!
- Mobility, Resistivity and sheet resistance
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