Dear Andrew,

1. Process a full batch of several wafers. Some will be used for development
of your RIE step.

2. RIE step: adjust your process conditions with some of the wafers from
your batch. Keep in mind that you need the depth tolerance since, due to
chamber and plasma geometry, acceleretaing plates geometry... the depth will
be different at the centerand at the edges of your wafers.

3. Proceed with the rest of your process

Keep in mind that if you want your process to be reproducible, all of your
conditions must remain the same. In other words, if you are etching silicon,
don't forget that Si oxidation is time dependant, beware of the
contamination of your tools, etc.

Ed


On Thu, Sep 2, 2010 at 3:30 AM, 杜 彦召  wrote:

> Hi all:
>
> Does anyone know how to control the RIE etch depth given no etch stop
> layer?
>
>
> Andrew