Wednesday, September 25, 2019, 18:06
Target boat with a layer of niobium foil on the bottom is used to heat up Nb samples to 1400 C for 4 hrs.
The niobium samples are wrapped in a Nb foil.
Boat is wrapped with 2 layers of Ta foil, careful to avoid touching samples.
Thursday, September 26, 2019, 18:10
The target assembly was exchange to a clean one e-log 459 and the Nb arrangement was loaded into evap2.
Friday, September 27, 2019, 18:13
HS water valves opened, no leaks detected.
Tapped up manually to 40 A.
IGP1 = 9.54e-7 Torr
Setting auto-ramp rate at 0.2 A/min to max setpoint of 100 A.
Vacuum stable.
Setting auto-ramp at 1 A/min to 300 A lead to ~1200 C.
Autoramping at 1 A/min to 400 A will stop at 1400 C.
Temperature reading is 1400 C at:
TGHT = 5.61 V, 345.656 A
The temperature reading went to 1408 C on Omega and 1417 C on Micron so the current was dropped to 342.537 A and 5.56 V
The temperature went to 1418 C on Omega and the current was dropped to 339.281 A
After 4 hours at 1400 C, the Nb was cooled down
The final pressure was 3.07e-7 Torr
The EVAP2 was vented with air and the Nb was removed. |