Hi folks -

I'm playing around with a new process and planning to try a copper wet etch.  I
know nothing whatsoever about available options short of the data in Williams
et. al "Etch Rates for Micromachining Processing, part 2".

Here are a couple questions I'm going to look into - but perhaps someone out
there can save me some time.

1 - Anyone know of an copper etchant with very slow relative etch rate for Al
(sputtered 2% Si), Ti, and Au?  It also needs to be patternable with standard
photoresist, and harmless to silicon nitride.

At the moment I'm planning to try Transene APS 100.  Williams gives a very low
etch rate for Al, and the company claims one can use titanium heaters in the
bath.  No data on gold, though.

2 - Has anyone had experience slowing down a copper wet etch?  (By changing the
temperature, dilution, etc.)  Any recipes known to work well?   I'm planning to
etch very thin films, and slowing down the rates would make timing a lot easier.


Thanks,
Erik


--
Erik Shirokoff
shiro@uclink4.berkeley.edu