Hello,

Try using the Transene Type A etchant for wet Al etch.


Best Regards,

Evgenia Golda Fradkin
Process Engineer
MEMS Group
Rafael LTD


-----Original Message-----
From: mems-talk-bounces+evgeniaf=rafael.co.il@memsnet.org [mailto:mems-talk-
bounces+evgeniaf=rafael.co.il@memsnet.org] On Behalf Of Christian Engel
Sent: Tuesday, March 15, 2011 10:34 PM
To: mems-talk@memsnet.org
Subject: [mems-talk] PVD of thick Al-Layer

Hello everybody,

for a project I need an Al-layer >2,5µm thickness. We are able to do PVD for
this. First question is if anybody has some advices for wet etching? I
thought about using ANPE, but we don't have any eyperiences with such thick
layers. Second question is, if there are any known oxydation barriers I
could use? Perhaps a thin Au-layer could work? But I am concerned about the
high etch-rate of Al in aqua regia, which I would use for etching Au.

Any advice is highly appreciated.

Best regards, Chris