Hi Hee Taek

Citric acid does etch the GaAs with etch rates 1.2
micron/min, However it depends that which direction you
want to etch if you want to etch it in <110> direction then
it is not possible becuase the <111> planes inhibits the
etch. If, you want to etch the structure in <100> direction
in that case it might be possible to etch with your desreid
 anisotropic etch.

We have etch about 40 micron deep etch of GaAs in <100>
direction with 2 -3 micron of lateral etch of GaAS.

I hope this information can help you to find out your
solution.

Kumar
Maryland MEMS Lab
University of Maryland
College Park, Maryland
MD-20742
--- HeeTaek Yi  wrote:
> Help me...
>
>     would you give me a information?
>
>      Actually I want to etch about 150 um etching only
> by wet ething the anisotrophy rate less than 0.1(150um
> : 15um).
>
>                     From taeggy
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