It looks like only the PECVD machine has the gas pipe that He runs
through. I haven't checked if I can run this pipe through RIE. What
would be the recipe if I can run He through RIE machine. On RIE CF4
looks like doesn't come with O2, but there is O2 gas pipe running
through RIE. So I don't quite get CF4+O2 at 6% means. Does that mean I
can run CF4 and O2 gases run in the chamber together?
Alim Polat
Linkoping University
Sweden

On Feb 5, 2008 3:24 PM, Bob Henderson  wrote:
> Alim:
>
> Do you have the ability to run Helium through one of your mass flow
> controllers? If not you could purchase a bottle of CF4 + O2 at 6% which
> might make the etch of SiO2 easier. Conditions of 40 sccm of CF4O2 a
> pressure of around 1 torr power of 3-400 watts rf should yield a good
> baseline for your etch process. If you use SF6 + He then 20 sccm SF6 + 100
> sccm He,  pressure around 1 torr, power of around 300 watts should yield a
> faster etch. Any standard positive photoresist at around 1.5 microns should
> hold  up to either etch process with a selectivity of around 3-5:1. Good
> luck. Bob Henderson
>