hi!
i wanna know the depth of layers.
i have 4 multi layer(silicon dioxide, silicon nitride, poly-silicon,
silicon nitride) wafer. but i don't know the way to measure the depth
of each layer during etching.
but i can't make a step.
because right now i can't use dry etch.
so i wanna use an ellipsometer.
if you have info about it let me know.
thanks in advance.