Finding the current in the drain of a MOSFET

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To find the drain current (ID) of a MOSFET, the gate oxide capacitance per unit area (Cox) is essential, which requires the oxide permittivity (εox) and oxide thickness (tox). The equations for ID in both the triode and saturation regions are provided, but without εox, calculating Cox is impossible. It is suggested to assume silicon dioxide as the gate dielectric, allowing εox to be looked up for further calculations. Once εox is determined, Cox can be calculated, enabling the use of the provided equations to find ID. This approach clarifies the dependency of ID on accurate values for Cox and εox.
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Homework Statement


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The equations provided require the oxide permittivity (εox)as well as the oxide thickness (tox) to determine the gate oxide capacitance per unit squared (Cox). How to solve this?

Homework Equations


In triode region: ID = μn * Cox * W/L * ((VGS-Vth)* VDS - VDS2/2

In saturation = μn * Cox * 1/2 * W/L * (VGS-Vth)2 * (1 + λ*VDS)

Cox = εox / tox

The Attempt at a Solution


Without εox, I can't get Cox; I can't start.
 
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tox is given. εox you should be able to look up. Assume the device uses silicon dioxide as the gate dielectric.
 

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