Monday, June 15, 2020, 13:30
Container coated with TaC and wrapped with 3 Ta heat shields.
Desired temperature= 1900 C, Omega Slope set = 0.990, Auto TGHT at 0.2A/min to reach 400A, TGHT will be tapped up accordingly to reach desired Temp.
TBHT will be set fixed at 230 A max).
Good vac at 3.00e -5 Torr
Bad vac at 5.00e-5 Torr
Chamber pump down
Tuesday, June 16, 2020, 08:55
IGP1= 4.2e-7 Torr
Starting ramp to 50A at 0.2A/min for both TGHT and TBHT. Observing pressure behaviour.
Tuesday, June 16, 2020, 14:14
IGP1 = 9.0e-7 Torr
TGHT = 50.3 A, 0.6 V
TBHT = 49.4 A, 0.54 V
Set TGHT to 400A and TBHT to 230A
Tuesday, June 16, 2020, 16:58
IGP1 = 7.32e-7 Torr
TGHT = 82.3A, 1.0 V
TBHT = 81.8 A, 0.96V
Will try to increase ramp rate to 2 A/min for both TGHT and TBHT
Tuesday, June 16, 2020, 17:30
Pressure spike.
IGP1 = 2.5e-5Torr
TGHT = 44.1 A, 0.57 V
TBHT = 43.0 A, 0.49 V
Will return to 0.2A/ min ramp rate for both heaters
Thursday, June 18, 2020, 20:26
Autoramped to 720A , 11.6V on TGHT at 0.2A/min
OMEGA = 1850C
Manually ramped to 740 A , on TGHT while TBHT remains at 230A
OMEGA= 1885 C
IGP1=4.6e-06 Torr trending down
Will remain at this temperature for next 4 hours
NOTE* Current on TGHT very unstable (oscillates)
Friday, June 19, 2020, 11:31
Last night at 00:15 am started cooling TGHT at -2A/min and TBHT at -0.2 A/min
(The elog entry was not submitted and computer restarted overnight so notes were lost).
at 6:30 am Friday June 19, 2020
Increased TBHT cooling to -2A/min and decreased THGT cooling to -1A/min
Monday, June 22, 2020, 13:54
IGP1= 8.1e-8 Torr
Evaporator vented and container pulled out. There is slight peeling near one end of the container. This area should be on the outside of the end-caps so the container should be usable.
Files to be uploaded later.
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