Dear MEMS community,

one of my customers is looking at patterning a resistor film
on top of an Aluminum based conductor (AlSi1Cu0.5)
Both of these are going to be UHV sputtered films.

Semi-final choices for the resistor material (TCR is not
really an issue) are TiN (preferred for process
flexibility), Ta2N, TiW(N) or TaAl.

Can anybody suggest a wet etch chemistry that would
selectively etch the resistor vs. the Al based
conductor ? Mainly for TiN and/or Ta2N on Al ?

I'm a bit out of my depth here, but if you have any
suggestions we'll be able to pick it up form there.

thx.
klaus
(TEEL) Tokyo Electron Europe Limited
European PVD Process Support
Klaus Beschorner                Tel +49-7033-45683
Drosselweg 6                    Fax +49-7033-45631
71120 Grafenau, Germany         Mobile +49-174 315 7754