[mems-talk] Seeking help on problem depositing a-Si on fused quartz

[huang]

Hi guys,

I was wondering if anyone has had similar problem before and has come up
with a solution.  I've had a lot of trouble trying to deposit and pattern a
100nm thick a-Si layer onto fused quartz substrate.

I tried liftoff and have been struggling trying to either it to stick to
the substrate.  I tried piranha clean, RCA clean, HF dip, as well as having
a thin (200nm) CVD SiO2 first before Si deposition.  Each time the film
washed away with 1165.  For the lithography step, I've been using an
established bi-layer process with PMGI SF11 under AZ4110 and made certain
that no resist remained in open areas by overexposing/overdeveloping/over-O2 descuming. For the a-Si deposition,  I've attempted both a high density plasma, SiH4-based 50C process and e-beam evaporation. I'm going to try etching next.


Any input will be greatly appreciated. 

Trent