Hi,

You have to use in this BOSCH process gases like

SF6+O2 in the etch phase and C4F8 in the passivation phase.

The oxygen used helps in sidewall passivation and also control the excessive
lateral etch rate. A  balance between SF6 and O2 provides the desired etch rate
.

 by increasing  RF power and pressure  you cant achieve a high etch rate like
3.5 ¦Ìmmin

recipe :

Etch cycle:  (25¨C30 mTorr), 130 sccm SF6, 13 sccm O2,
600 W Coil/23 W  RF
Passivation cycle (15¨C20 mTorr), 120 sccm C4F8,
600 W coil,
Total process time: 60 min

Regards to all .

Naitbouda Abdelyamine
Process Engineer in the Dry etch area
of the Clean Room of the CDTA.
Centre de Developpement des Technologies Avanc¨¦es
Cite du 20 Aout 1956 Baba Hassen,Alger,Algerie
anaitbouda@cdta.dz