wet etch release should be very easy. Just make 2micro*2micro holes
everywhere on your device layer. And 2 or 3 micro between adjacent holes
would garantee the release.  We used HF 49% for 3mins or more (depends on
how much area was exposed).

Jie

On Wed, Nov 26, 2008 at 10:31 PM, Yan Xin  wrote:

> Hi everyone,
>
> For the inertial sensors, we usually need to perforate the suspended
> structure to release the structure with wet etching process.
> -But how to know if the holes are big or dense enough to release the
> structure
> completely?
>
> For example, in the SOIMUMPs process, the oxide layer is 1 microm, the
> structure layer is about 25 micron, undercut is 1.8 micron per side by  HF
> vapor etching,
> -Does this mean that  the distance between edges of  two adjacent etched
> holes must be less the 1.8*2 micron if i need  to release the structure
> completely?

*  Zou Jie (Jay)
*  Department of Physics
*  University of Florida
*  Tel: +1-352-846-8018
*  Email: zoujiepku@gmail.com
*  Homepage: http://plaza.ufl.edu/zoujie/