Lab Tour, part 1 - Metrology Bench

Several people, upon seeing some of the photos taken during my work, have asked for more information about my lab setup. I've been posting so many photos taken through my microscopes lately that I seem to have forgotten to post any of them!

This is the first post in a series of several. My lab is divided up into a series of distinct work areas and I'll be doing a post or two about each.

First off, an overview of the space:

Overview of metrology bench

The 19-inch rack at the right of the bench holds the image capture workstation (a 2U server recently removed from my GPU cluster), a Cisco 2950 switch, and a 24-port patch panel.

Moving to the left, the next notable piece of equipment is the Wentworth Labs probing station.

Probing station

The probe station is equipped with a 4-inch vacuum chuck, but I have to tape samples down at the moment due to lack of a vacuum distribution system. (This is on my longer term projects list).

The microscope is a B&L Stereozoom 4, with magnifications adjustable from 7x to 120x in full stereo. Although the images are not quite as sharp as most of my other scopes at high magnification, the addition of depth perception is extremely useful for probing and other manipulative tasks. It lacks an epi-illuminator so a fiber optic lamp is positioned to the right side of it.

I currently have three Micromanipulator 110/210 micropositioners. They're the same except one is meant to go on the left side of the chuck and one goes on the right. They're intended for large targets (20μm range, I think) such as bond pads, and are not suitable for smaller structures.

For probes, I use pieces of tungsten wire electrochemically etched to fine points. I'm still working on optimizing this process and will likely do a post on it once I get something working better.

Left side of metrology bench

The left-hand instrument in this view is an AmScope metallurgical microscope equipped with 4, 10, 40, and 100x (oil) objectives. It was my first high-power microscope and was OK but not great; the stage flexes when panning and the focuser seems to drift slightly. Some chromatic aberration is visible at higher magnifications.

The AmScope has been my main lithography tool so far; I will probably be removing it from service once my 2-inch contact aligner is finished.

The right-hand tool is an Olympus metallurgical microscope equipped with 5, 10, 20, and 40x objectives and is capable of both brightfield and darkfield illumination. It's a mix of BH and BH2 series parts scavenged from ebay.

The Olympus is my primary imaging system, its one notable deficiency is that at the moment it does not have a 100x objective. I purchased a used NeoSPlan 100x objective recently but this is infinity corrected (unlike the Neo objectives currently on the turret) so some modifications to the scope will be necessary to use it.

Off to the left side of the bench are various slides, coverslips, and sample preparation supplies.

I have several other measuring instruments that are portable and go wherever in the lab they're needed, but decided to cover them here in keeping with the general theme of metrology:

Scales and calipers

The left-hand scale has a capacity of 200g and is graduated in tens of mg; the right hand one has a capacity of 20g and is graduated in mg.

The digital caliper in the upper left is graduated in 0.001 inch increments but has a fairly large range of measurement and can do both inside and outside dimensions.

The final instrument is the Mitutoyo digital micrometer in the upper right. It only has a range of 0-1 inch but is graduated in μm. In one test I was able to easily measure the thickness of the photoresist film on top of a printed circuit board.