Hi Lee,

Welcome to the field. A good place to start for information on wet
chemical etch rates follows:

Muller and Williams
"Etch Rates for Micromachine Processing"
Journal of Microelectromechanical Systems (JMEMS)
Vo. 5, No. 4, Dec. 1996.

In this paper, you will find that a 25:1 solution of DI:HF will etch dry
oxide at 95 angstroms/min.

Good luck!

-Craig McGray
 Dartmouth College


[email protected] wrote:

> Message: 9
> Date: Wed, 19 Mar 2003 10:47:35 +0900
> From: "Sungjun Lee" 
> Subject: [mems-talk] Etch dry oxide
>
> Dear all:
>
> I'm a beginner of MEMS field.
>
> After e-beam lithography with 100nm PMMA,
> I would like to etch silicon DRY oxide less than 80nm height.
> The size of the pattern of e-beam lithography is 200~300nm.
> I also hope the slop of the echted wall is NEGATIVE.
>
> Could you recommend any CONTROLLABLE chemical(wet) methods for this
work?
> I heard the normal HF have a fast etch rate.
> Any comments are welcomed.
>
> Thanks in advance.
>
> S. Lee / Graduate Student