Dear Steven,

Personally I have sputtered Pd (which is chemically similar to Pt)
directly on virgin prima Si (with native oxide). The deposited coat
(which was ~20nm in my case) was stable against common organic and
inorganic solvents (ethanol, acetone, water, toluene). I do not know if
it will be stable in piranha, but it is possible (Pt is normally
dissolved in aqua regia). When my Pd layer was exposed to air plasma
(i.e. a mild oxygen plasma), the Pd was initially stable (also in
solvents), but would start to flake when exposed to a reducing agent. I
hope this information helps.

Kind regards,

Dirk Renckens
PhD student - TU Delft

-----Original Message-----
From: Steven Yang [mailto:steven030505@gmail.com]
Sent: 16 February 2008 10:47
To: mems-talk
Subject: [mems-talk] Is it possible to deposit Pt directly on
Si/SiO2(PECVD) substrate?

Hi, all

Not sure the Pt (sputtering) will stick firmly on the substrate or
not? as normally Ti/Pt is used for the electrode deposit. But I am
going to try Pt directly on Si substrate with PECVD SiO2 (1 or 2 um)
due to machine limitation.


and if possible, will the Pt electrode firm enought to go through some
processes like Piranha, O2 plasma?

Thank you very much!

Steven