Beam on FC6 drifted overnight. Touch up a few things, notably the EE. 25pA on FC6 presently. I also increased microwave power for effect.
Later... about 25pA on FC6. Somewhat noisy, but also stable. I left microwave at 700W. Beam handed over to ICR at ~13:15.
A note about mass flow controller. The new Hastings controllers do indeed shut off completely at zero setting. It should be noted that control in the sub-1sccm region is challenging. Move in 0.01 steps. I found that everything was fine down to 0.15sccm. The next step after that, i.e. to 0.14, closed the flow entirely. Not a crisis in this situation. |