Replacement power supply ....
shott at stanford.edu
Thu Feb 26 12:53:48 PST 2009
We are in the process of replacing the problematic Drytek RF power
supply with a more supportable ENI supply. At the moment, this supply
is sitting adjacent to the Drytek on the floor but we hope to have it
more or less in place of the normal power supply by the end of this
There are two or three minor changes in the way that the system will
1. When the instructions say to turn on and off the circuit breaker on
the Drytek RF supply .... you should turn on and off the circuit breaker
on the ENI supply.
2. The LED readout of forward and reverse RF power will now read zero
(unless it is reporting an error condition). There is now a little
remote readout box that has both forward and reverse readouts and,
unlike the old Drytek, this will now read both forward and reverse power
with a resolution of 1 W instead of 25 W.
3. If reverse RF power exceeds about 50 W, you will see a yellow LED
light up. If this happens, the forward power will also be reduced to
protect the supply. As a result, it is important that you run a dummy
run in advance of running real wafers to make sure that you are very
close to the match point.
Note: although it will soon be "buttoned up" there is currently an open
interface box sitting on top of the ENI supply. While you should not
disturb this, there are no lethal voltages in that box .... nothing more
than 15 VDC, in fact.
Note: we've compared the readout on the analog power meter with the Bird
meter and with the digital readout. They all agree within a few watts,
so I believe that previous readings of 500 W (which, of course, have not
been achievable for some time ....) on the Drytek readout should closely
match the power observed on the ENI when it reads 500 W.
Let me know if you have any problems, questions, or concerns.
More information about the drytek2