Dear Ning,

here at our lab at ETH Zurich we used the commercially available tool
from AMMT (www.ammt.de) in Germany since April this year. We perform
release of mechanical structures from SOI wafers (thermal oxide) as
well as sacrificial-layer removal on fully processed CMOS substrates
(LPCVD oxide). The AMMT tool provides an option for sealing and
protection of the wafer backside during etching, which is important
for our CMOS compatibility. We use the 100-mm version and had the
process under control after a few days. In terms of safety (important
when working with HF), the tool is well designed and the operator does
not need to touch any HF contaminated parts of the system.

Best regards,

Jan

*******************************

Dr. Jan Lichtenberg
Team Leader Biosensor and Microfluidics Group

Physical Electronics Laboratory
ETH Zurich
Hoenggerberg, HPT H4.2
CH-8093 Zurich, Switzerland

WWW:    www.iqe.ethz.ch/pel

*******************************


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Wednesday, December 8, 2004, 1:43:19 AM, you wrote:

> Dear colleagues,

> Vapor HF etching of the sacrificial layer has been widely used in MEMS
> fabrication. Does anyone have any good experience with a Vapor HF tools
> (i.e. FSI, Semitool, AMMT, etc) that is suitable for both R&D and
> production. This requires good uniformity across the 6'' or larger wafers,
> good wafer to wafer consistency, minimal stiction problems, and predictable
> etch rates. any information would be greatly appreciated.


> thanks!


> Ning Chen
> MEMS Processing Engineer