[labnetwork] Query regarding ICPRIE system-IIT Bombay_India

[Robert M. Hamilton]

Satyavalli Palur

You should have a pressure regulator in the BCl3 gas 
cabinet. It should be set for ~2 psig delivery pressure in 
order to avoid the possibility of condensation (phase 
change) in the delivery line. A setpoint of 2 psig will 
provide you some head-room as the pressure of BCl3 pressure 
in the cylinder, at room temp, is ~ 4.4 psig. There are a 
number of good, low and sub-atmospheric pressure regulators 
available for such gases so make sure the regulator is 
designed for low pressure delivery.

We recently had an issue with a SiCl3 line that was routed 
under an supply air intake. Periodically, the inlet 
temperature was low enough to condense the SiCl4. We 
compensated by dialing down the delivery pressure while 
making sure we still had enough pressure for maximum recipe 
flows at the tool.

If you do have issues with meeting BCl3 demand at a reduced 
pressure you may want to check the setup of the BCl3 mass 
flow controller. Typical "generic" mfc's are setup for use 
at 18-22 psi delivery pressure. An mfc calibrated for BCl3 
will likely be set correctly.

Bob Hamilton

Bob Hamilton
Marvel NanoLab
University of CA at Berkeley
Rm 520 Sutardja Dai Hall
Berkeley, CA 94720-1754
bob at eecs.berkeley.edu
(e-mail preferred)
510-809-8600
510-325-7557 (mobile - emergencies)

On 3/26/2013 4:07 AM, Satyavalli Paluri wrote:
> Thank you very much for the very good suggestions and feedbacks we have
> received from you all. This information shall be passed on to our students
> and staff who work on the instrument. We will discuss and revert back to
> you if we have any further queries.
>
> Thanks once again!
>
> Valli