OSU Microscopy Center

The OSU Electron Microscopy Facility located in Linus Pauling Science Center

Tate group contact is Bethany Matthews Chris Reidy.

• FEI NOVA NanoSEM 230 - High resolution SEM with in lens detector
• FEI Quanta 3D SEM/FIB
• FEI Quanta 600F FE SEM
• Philips CM12 STEM
• Leica DM 5000 Optical Microscope
• Sample Preparations
• Simulation Software

Quanta SEM Manual

Helios SEM Manual

• Primer on TEM from ETH, Zurich
• TEM Workshop by Shah, UIUC

Recently we have had both spectacular nano particle images come from the Titan and other images that are not so high quality. Much of the issue is sample prep and grid selection. For example, using too much solution (water or ethanol) and or not making the grid hydrophillic with glow discharge prior to pipetting solution to the grid. Please see the attached word file (below) and ask us if you have any questions at all.

Nano Particle Grid Preparation Pete Eschbach and Teresa Sawyer Electron Microscope Facility, OSU

1. First step is to select the grid for the job. We have a handout in the lab in the grey inboxes on the South side of conference room. Please ask us if you have questions, we are here to help. An ounce of preparation saves a pound of grief later! Ultrathin carbon or holey carbon is the best suited for fine nanoparticles. If beam stability becomes an issue, you will need to up the thickness of carbon. If I were to by one grid it would be a Ted Pella 08142 or 08142G(gold), this is a 300 mesh grid with a ultrathin carbon support film for high resolution imaging. It is more fragile than a traditional carbon coated Formvar but offers high resolution TEM imaging in the holes!

A new alternative is Quantafoil from EMS, EMS numbers such as Q225-CR2. Quantafoil makes low dose techniques work as the hole pattern is regular and the beam can be shifted a preset amount every time. 2. Plasma treat your grids to make them hydrophilic (attract water). We do this with the home built glow discharge in the EM Facility sample preparation room. But, we just ordered an EasiGlow system from Ted Pella to make it easy for students. 3. Now get 3 tweezers with O ring to lock the jaws of the tweezer. Pick up a grid in each tweezer and lock it in with an O Ring. There is a handout in the lab of supplies that will make grid handling easier. 4. Now dispense 2-3 uL of your nanoparticle suspension on the grid. 5. Wick off excess after 1 -2 minutes. 6. Let it dry overnight in a clean dry nitrogen cabinet or a desiccated cabinet. 7. Release your grid into a grid box by moving the O Ring off the tweezer. 8. Lab staff will be happy to show the fine points for grid preparation.

Dear Colleagues,

More updates in EM Facility below:

Nova NanoSEM 230 high-resolution SEM has been installed and signed-off, and will be ready for use from the beginning of next week. Functions are summarized below:

1. 1 nm Resolution at 15 kV, less than 1.6 nm at 1 kV;
2. High vacuum mode (conductive sample) and low vacuum mode (non-conductive samples);
3. X-Ray EDS chemical analysis (EDAX, Inc);
4. Electron decelerating to several hundred volts, reduce the landing velocity of electrons on samples – to reduce beam damage, and charge effect for non-conductive samples;
5. Everhart-Thornley detector (ETD) for SE and BSE signal detection from outside of column, suitable for working distance > 5mm;
6. Through-Lens Detector (TLD) inside the column (immersion mode), for detection of SE and BSE signals, suitable for working distance < 5mm and high resolution imaging;
7. Low vacuum high contrast detector (vCD) for low kV image, especially when electron decelerating function is used;

In order to make training smoothly, we will start training to users who have already authorized to use either Quanta 3D, or Quant 600F.

The installation of Titan 80-200 high resolution TEM will be started next week or the following week. Philips CM12 STEM will be decommissioned by the end of February, no later than end of March, depending the progress of the installation of new TEM.

More are coming!

Best Regards, Yi

Yi Liu, Ph.D, Director Electron Microscopy Facility 145 Linus Pauling Science Center 2900 SW Campus Way Oregon State University Corvallis, OR 97331