Re: Cr etchant: etching rate?

For the Cr etchant that we have in lab (Cr-14), the etch rate should be ~93nm/min from literature. Note that our Cr etchant is expired (since April 2009), so literature etch rates may not be reliable.

From experience, the etch seems to start only after ~30sec in solution, and the etch rate is quite fast. In about 1 min, I could etch 10nm Cr. It doesn't seem like the etch rate is linear in time and varies greatly (perhaps because it is expired), so it may undercut resist patterns significantly.

Best,

Dany

On Mon, Mar 29, 2010 at 10:27 AM, Kyunghoae Koo <koo1028@stanford.edu> wrote:

 

Dear Labmembers,

 

What is the etching rate of Cr etchant in snf? I need to etch 2nm buffer Cr layer. Lateral etching is not a big issue. How much time will be enough for that?

Thanks

 

Kyunghoae

 

 

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Kyung-Hoae Koo

PhD candidate

Stanford University

EE department