etching depth of 500um

[Chris Kenney]

You can use the focus knob on a microscope to measure the
depth with a few microns accuracy. Use as high a magnification
as you can for smaller errors.

It's nice to calibrate the focus know with an object of know height.

With channels this wide and with a low aspect ration you should
be able to focus on the channel bottoms.

Chris


On Fri, 9 Apr 2004, Fu-Min Wang wrote:

> Dear labmembers,
>
> I am looking for the feasibility of etching a 500 um wide channel down to 500 um deep and I will look for some thicker wafer about 600-700 um. Two issues here: (1) how do you accurately control the etch depth of 500 um ? (2) How do you precisely measure the depth of 500 um range? Your suggestions are highly appreciated.
>
> Fumin
>