# Investigating the effects of changing the length and width of transistor channel

1. Nov 9, 2011

### SMOF

Hello,

I posted this here because it is for a bit of course work, but I am just looking to confirm if I am using the right equation. I hope this is ok! If not, sorry! I just didn't think since I was asking a specific assignment question, I would post here.

I need to investiage how changing the width and length of a transistor channel effects the threshold voltage. I need to do this in a simulation package and in theory. The simulation is grand, so now I just need to back it up.

I have been given a few parameters, such as a starting threshold voltage, figure for mobability, thickness of oxide. So, would I be correct in using, and rearranging the following equation to see how the Vt changes?

Id = β ((Vg-Vt)Vd - Vd2/2)

Where β = ($\mu$0 W Cox/L)

I have some issues rearrenging equations, but if I know I am on the right path, I can work on it.

Seán

2. Nov 10, 2011

### SMOF

Opps, guess I did post in the wrong place.

Sorry!

Seán