Hi, Thierry :
    Thanks for this! But I don't know SD-2 glass is which company's
products? Is it from Coring too?
    Beside that, I had read your paper which uses anodically bonding Si as
etching mask, it's good! But we have poor resource here in Taiwan, we can't
do so deep dry etching ...
    I haven't read about why Cr/Au mask can't resist HF etching, I read this
in another paper too, but I haven't found why...
    The usally mentioned conventional Cr/Au mask's thickness? Since so many
paper mentioned it, it must be that no matter how thick it is, the mask
won't resist long in HF, right?
    Thanks for your suggestions, if I can find SD-2 in Taiwan, maybe it's a
very good solution!!
Sincerely,
____________________________________________
Jerry Lee
(Jia-Hong Lee)
Insitute of Applied Mechanics,
National Taiwan University
Taipei, Taiwan, ROC
e-mail:
iamjhlee@email.com
r6543023@gauss.iam.ntu.edu.tw
"Try then error is better than no try"
-----Original-----
±H¥óªÌ: Thierry Corman 
¦¬¥óªÌ: Jia-Hong Lee ; mems-cc@ISI.EDU

¤é´Á: 1999¦~2¤ë25¤é PM 06:34
¥D¦®: Re: Etching Mask for BSG(Corning 7740)?


>Hello Jerry,
>
>I suggest you to look at the following papers:
>
>Thierry Corman, Peter Enoksson and Göran Stemme, "Deep wet etching of
borosilicate glass using an anodically bonded silicon substrate as mask",
Journal of Micromechanics and Microengineering 8 (1998) 84-87.
>
>Shuichi Shoji, Hiroto Kikuchi and Hirotaka Torigoe, "Low-temperature anodic
bonding using lithium aluminosilicate-B-quartz glass ceramics", Sensors and
Actuators A 64 (1998) 95-100.
>
>As described in these two papers it is difficult to etch deep in pyrex
glass with a conventional Cr/Au mask. A practical solution is to use SD-2
glass instead of pyrex, which etches faster than pyrex with less
underetching: with a conventional Cr/Au/resist mask it is possible to etch
through the SD-2 glass (500 µm). As pyrex, SD-2 is suitable for anodic
bonding with silicon.
>
>Good luck!
>
>Thierry