This is the journal. See the Edwards AUTO 306 Coating System project page for an overview.

Further work on the e-beam. Successfully evaporated Al (~140nm, multiple runs) on Cr (~1nm) on glass. Good adhesion.

Al is very slow to evaporate for some reason.

Successfully evaporated Al on Si.

Successfully evaporated SiO2 on Al on Si.

The cooling capacity from the chiller is a bit on the low side, especially when evaporating Al. It seems beneficial to go 'fast and hard' and let the system accumulate heat just for a short period of time rather than slowly depositing very little material but causing the temperature of the cooling water to increase past 35 degrees.

Rewired the thermal evaporator for 3 phase supply and installed infrastructure for it. It runs from a 16A circuit now, and has a separate 4mm² potential bonding connection.

A separate socket on the same 16A circuit will follow for the sputter coater. This means you shouldn't run them both at the same time.

E beam supply has been tested and working. We had to manually enable the water flow sensor interlock input on the control cabinet (purple jumper wire).

Getting the e-beam to run was annoying - turns out the system needs to be in 'process' mode.

First attempt at starting the sputter system. Hotwired just the Edwards supply skipping Wedel's interlock and pumped down. 3.4E-5 mbar ultimate pressure. Examined the plasma high voltage box - in current configuration it looks like it's just a rectifier + series resistance.

Added a manual vent valve to one of the flanges on the back. Replaced the blocked up sintered KF ring on the vent path with a plain ring. Plasma works, with some arcing around the electrodes - possibly breakdown of the built up film?

Plasma experiments. Chamber is really filthy and nonconductive, that might be an issue in building a nice plasma across the whole chamber.

Roughly cleaning the chamber with scotchbrite, blue towels, kimwipes soakes in isoprop as a proof of concept to see if surface becomes conductive and a better plasma can form.

Played with some coating tests, see Lab Notes for FAFO Semiconductor Processes (2026-04-25).

Vent valve was not stuck - a sintered KF filter ring in front of it was. Removed filter ring, replaced with normal ring. Chamber now vents aggressively, added a flow restrictor outside that also acts as a very coarse filter.

Film thickness monitor worked for a while, but now seemingly detects a broken crystal. Need to read more into the manual.

Successfully coated Al on glass. Glass slide was held with Aluminium foil. Need better substrate holder for small/experimental pieces - to be designed.

Evaporator:

Powered main cooling valve from external 230V. Checked main cooling loop for leaks. Seems ok. Marked valves for the two loops.

Chiller unit couldn't deal with restricted flow form main cooling loop (in series: turbo pump, baffle, quartz microbalance). Put microbalance in parallel with turbo pump and baffle using press-fit T couplings.

Rewired control box (in rack) to work off a single phase. Three phase is only needed for E-Beam power supply. Moved phase for 24V supply onto phase 1 too.

Interlock form control box didn't seem to enable turbo controller (lines 13/14 on I/O connector). Bypassed for now, cable marked.

Vent valve didn't seem to be actuated from the control box. Manually enabled for now.

System went down to vacuum but not without a fight (timeouts, etc. - needs a good pumpdown for a few hours). Cleaned main seal. Managed to strike a plasma via HT. Managed to blow out thermal evap boat via LT.

Turbo is very loud. Probably worth checking if we can recondition it.

Shutter operates but slowly. Probably needs regreasing of its o-rings. We might have a replacement rotary feedthrough.

Target rotation works as operated from the panel.

Source change works as operated with the right knob.

Needle valve operates. Butterfly valve in front of needle valve seems to leek - needle valve must be closed on each use.

Brought the two coating systems and the control cabinet into our lab.