Vacuum Chamber

This was the first project I was assigned as of joining Dr. Jaesung Lee’s laboratory. As we do a lot of MEMS work, vacuum chambers are par the course. However commercial options are expensive and don’t offer the slew of features or modularity we require.

So I started on a design. I have a background in CNC machining so the chamber was approached with CNC Mills in mind. No sharp internal corners, bit length considered, keep the number of tools down, as few operations as possible, etc…

• The chamber is 6.75″ wide by 3″ deep, and 2.5″ tall, and boasts an internal volume of approximately 22 cubic inches.

• It supports 12 coaxial inputs fed through 5/16″ through holes
• Air is controlled via two KF 1/4″ NPT vacuum quick connects
• There are two windows
  • The primary and upper window is for microscopy, and features a 2mm thick optical window which when installed has a viewing diameter of 1.5″. The mounting allows the sample to get as close to the optical window as possible without impacting microscopy.
  • The secondary and laterally mounted window is for viewing. Having a good viewing window is key to allowing quick testing and verification of setup.
• Finally the chamber is modular, the default setup features a optical breadboard bottom module, and viewing window top module, however there is no reason other modules couldn’t be stacked. Future plans include a water cooling module to allow Peltier thermal control systems.

Total system cost (helped by university subsidized machining) came out to ~$2,350.

A full pricing breakdown

Name of Item	Order Quantity	Cost per Item	Total Cost	Notes
Window (50mm dia & 2mm thickness)	2	$262.50	$525.00
Window Gasket	1	$9.84	$9.84	Comes in packs of 25, actual required: 2
Coaxial Feedthrough	12	$55.99	$671.88
Vac/Air Feedthrough	2	$79.86	$159.72
Main Gasket	1	$13.24	$13.24	Comes in pack of 10, actual required 2