Deepa,
         Please try this ratio
CHF3:O2::30:7,pressure=300 and power =100.etch rate =200A per min.It will take
some 40 to 45 min for you to etch 8000A.
good luck
bye
jaibir

On Mon, 17 Sep 2007 deepa sree wrote :
>   Hello All:
>     I am having difficulty in etching a silicon oxide layer that I deposited
in a Plasma therm system with Silane and Nitrous oxide. Thickness is about 8000
A. It etches really fast (about 30 seconds) in 5:1 BOE, but doesn’t etch
at all in a dry etch system. I am using Oxygen and CHF3 for etching. I have
tried various gas ratios, power and pressure settings, but I am not able to etch
this layer. I need to use a dry etch for my application. Any suggestions about
etch or deposition is appreciated.
>      Thanks
>   Deepa
>
with regrads

Jaibir Sharma
Reasearch Scholar(PhD)
Electrical Department,
IIT Madras,
Chennai - 36
INDIA

Phone:044-22575444(off)
      09840396872(home)