Hi Ben!Great post, as always. I especially appreciated your discussion of the things that don't work as well as your successes. For us spectators it is easy to forget that science and invention requires a LOT of trial and error and perseverance. One of my favorite quotes on the subject is from Edison "Invention is 1% inspiration and 99% perspiration". My other favorite, I'm not sure of the origins: "In science, never say oops. Only, 'Ah...interesting'". Good luck, I'm sure you'll figure it out soon!
I wrote out a nice big long post and then I lost it in the log on rigmarole. They might check your ability to post before presenting you with a dialog to enter a new comment, he said shaking his head disapprovingly.I ran you down on my pedigree– what a bigshot I am. Here's what I said: try charging the substrate with electricity – see if you can coax the vapor to deposit like the morning dew. |I am Addison Phillips on YouTube.
A little acceleration can't hurt. Also, which you probably know since you're using the better method already, some of the evaporated molecules are ionized and with a little bias voltage can result in a measurable current representing the material flow (deposition rate). This may require UHV.Thanks for sharing, btw, interesting projects well executed..
Are all 6MHz xtals sufficiently similar in geometry that deposition mass (to change the frequency) corresponds directly to a certain change in thickness? Or do you somehow calibrate for the geometry parameters of the canned xtals?
beambot, it's a good question. I would likely need to calibrate the TTL oscillator crystals, since their outer diameter is different than the typical 6MHz crystals used for thickness monitoring. Luckily, someone gave me a Inficon sensor head, so I'll be using the correct crystals when I get everything mounted.