PE2-1.1 MOS Device Physics & Modelling
You can derive the MOS drain current and threshold voltage, account for second order effects, draw the device layout and capacitances, and use the low-frequency small signal model including short channel behaviour.
Deriving the drain current once yourself is what separates using a transistor from understanding it, and the square-law result is the foundation every later stage builds on. The second order effects are where reality intrudes — channel length modulation, body effect, velocity saturation — and in short channel devices they stop being corrections and become the behaviour. Device capacitances matter because they set every frequency response in the rest of the course.
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MOS structure and basic device physics
The device this whole course is built from, at the level of what the physics is doing. Everything above it assumes this item, so it is worth the time even if it feels like revision.
MOS I/V characteristics; threshold voltage
The current-voltage behaviour, and the voltage at which the device turns on. Threshold is the parameter every later design equation contains.
Derivation of drain current
Working the current expression out rather than being handed it. Doing the derivation once is what makes the regions of operation stop being arbitrary.
Second order effects
The ways the simple model is wrong: channel length modulation, body effect and the rest. Analog design lives in these corrections rather than in the ideal equations.
MOS device layout
How the device is drawn for fabrication, which decides its parasitics. It is where the abstract width and length become a physical shape.
MOS device capacitances
The capacitances between terminals, which set the speed of everything. They are the reason the frequency response item at the end of the next topic exists.
MOS low frequency small signal models
The small signal model, which is how analog design actually proceeds. Committing the model to memory pays back immediately in the next topic.
Long channel versus short channel behaviour
How behaviour changes as devices shrink, which is the whole story of the industry. The short channel effects are why the simple equations stopped being enough.
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