Veeco MPS-3000 CE, Technical Manual

Page: 31 / 96

27
c. Increase the gas flow to the ion beam source by about 1sccm and
repeat Step 10.
•
If necessary, repeat Steps a. and b. until either a flow rate of
10sccm or a chamber pressure of 6.7 x 10
-2
Pa (5 x 10
-4
Torr)
is reached.
• If the discharge still will not start, refer to the “Troubleshooting/
Error Code Definitions” on page 69 and to the ion source
technical manual.
11. Select the beam voltage. For initial start-up purposes, use a value of
1000V.
a. Select the Beam power supply with the MODULE switch. Voltage
will automatically be selected in the Manual mode. The words
BEAM and VOLTAGE appear above the appropriate switches.
b. Enter the chosen voltage by turning the Adjust knob. The changing
values appear on the Beam Voltage display.
c. As the Adjust knob is turned, the beam voltage is entered automat-
ically into the selected memory.
12. Set the A/B Ratio.
The recommended and factory-set A/B Ratio is 10% for all sources.
a. Select the Accelerator power supply with the MODULE switch. The
letters ACCEL appear above the switch.
b. Select the A/B Ratio with the FUNCTION switch. The letters A/B
appear above the switch.
c. With the Adjust knob, select the accelerator-current-to-beam-cur-
rent ratio. The A/B Ratio appears on the Accelerator Voltage dis-
play.
d. The final selected ratio is stored automatically in the memory, as
indicated above the MEMORY switch.
13. Select the accelerator voltage. For initial start-up purposes, use a value
of 250V.
a. Select the Accelerator power supply with the MODULE switch and
Voltage with the FUNCTION switch. The words ACCEL and VOLT-
AGE appear above the appropriate switches.
b. Enter the voltage by turning the Adjust knob. The changing value
will appear on the Accelerator Voltage display.
c. As the Adjust knob is turned, the accelerator voltage is entered
automatically into the selected memory.
14. Start the ion beam.
To avoid electrical shock, keep clear of “live” circuits.
NOTE
WARNING