Leica S430 Scanning Electron Microscope

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Leica S430 Scanning Electron Microscope
SEM.jpg
Owner/Loaner PS:One
Serial Number 430-02-01
Make/Model Leica Stereoscan 430
Arrival Date 3/23/2013
Usability yes
Contact Ryan Pierce
Where Near shop entrance
Certification Needed yes
Hackable NO
Estimated Value $100,000.00

Leica S430 Scanning Electron Microscope https://wiki.pumpingstationone.org/Leica_S430_Scanning_Electron_Microscope


Configuration

  • Secondary electron detector (functional)
  • 4 quadrant silicon backscatter detector (non-functional, troubleshooting in progress)
  • Oxford Isis EDX detector (working, requires liquid nitrogen to operate)
  • High Resolution Recording Unit (HRRU) (not currently connected, Polaroid film no longer produced)
  • Ethernet. Scripts set up to FTP image files for each user to ftp://semsrv.pumpingstationone.org which is accessible only inside PS:One's network.

Certification

This is probably the most complex piece of equipment we own. As such, certification will be broken into different levels which qualify a user to perform only certain specific tasks. Unlike other PS:One equipment where anyone certified can, in turn, certify anyone else, at present the only person who may certify others is Ryan Pierce. We anticipate we will have additional trainers in the future.

Scanning Electron Microscope User

This level enables the user to observe samples already prepared and placed in the chamber. Users at this certification level may:

  • Observe samples already left in the chamber.
  • Use the Secondary Electron detector.
  • Observe their own samples if prepared and placed in the chamber by someone with Sample Preparer certification.
  • Adjust standard software settings.
  • Align the aperture, and change between apertures.
  • Vent the chamber and restart the vacuum pumps. (only if necessary)

Users possessing this certification may not:

  • Use the Backscatter or EDX detectors.
  • Open the chamber and manipulate samples.
  • Adjust gun alignment.
  • Open the gun assembly, change filaments, anodes, etc.
  • Replace apertures.
Qualified Member Trained By
Ryan Pierce Ryan Pierce
Steve Finkelman Ryan Pierce
Tucker Tomlinson Ryan Pierce
David Fell Ryan Pierce
Tony Coleman Ryan Pierce
Lisa Coleman Ryan Pierce
Patrick Schless Ryan Pierce
Everett Wilson Ryan Pierce
Elizabeth Koprucki Ryan Pierce
Andreas Dahl-Hansen Ryan Pierce
Justin Conroy Ryan Pierce
Dmitry Baycharov Ryan Pierce
Jerry Lebedowych Ryan Pierce
W J Perry Ryan Pierce
Jay Hopkins Ryan Pierce
Hef Ryan Pierce
Aaron Carlock Ryan Pierce
Andrew Kos Ryan Pierce
Todd Allen Ryan Pierce
Skittles Ryan Pierce
John Rudnick Ryan Pierce
Cameron Rudnick Ryan Pierce
Mike Warot Ryan Pierce

Backscatter Detector User

Users possessing this certification may:

  • Move the four quadrant backscatter detector in and out of the beam path.
  • Image samples with the 4QBSD.

As the 4QBSD is currently undergoing maintenance, this certification is currently on hold. It will be rolled into the Microscope User certification and made part of that curriculum at a future date.

EDX Detector User

Users possessing this certification may:

  • Operate the EDX detector.
  • Fill the EDX detector with liquid nitrogen.

As PS:One does not have a readily accessible method for transporting liquid nitrogen, this certification is currently on hold. Donation of a large Dewar (10 liter or greater) would be of immense help to make this happen.

Sample Preparer

Users possessing this certification may:

  • Mount samples on stubs.
  • Use the Technics Hummer V Sputter Coater to sputter coat sample stubs.
  • Vent the SEM chamber.
  • Load and unload samples from the chamber.
  • Pump down the SEM chamber.

This certification is currently on hold pending repair of the sputter coater and acquisition of an argon tank for the sputter coater.

Microscope Maintainer

Maintainers perform all maintenance on the microscope, including:

  • Changing filaments
  • Aligning the gun
  • Replacing the anode
  • Cleaning the gun assembly
  • Replacing apertures
  • Adjusting software configuration
  • Anything involving disassembly of the microscope
Qualified Member Trained By
Ryan Pierce Ryan Pierce

Suppliers

  • SPI Supplies[1]
  • Ladd Research[2]
  • Ted Pella, Inc[3]
  • Tring Enterprises[4]

Supplies

  • Front panel light bulbs: These use #85 28V miniature bulbs.[5] The scope came with many of these.
  • Edwards EMF20 oil mist and odor filters: [6] has the best price I could find. These are two separate elements, and one may need to be replaced while the other may be fine.

Documentation

Network Config

SEMSRV is the FTP server. The SEM and the EDX are Windows 3.x era machines, and are currently configured via BOOTP. The current Mikrotic router does not send DNS server information with its BOOTP responses.

Machine MAC Address
SEMSRV (virtual Linux FTP server) 1E:0B:6B:E6:2D:9C 10.100.0.16
SEM 00:00:C0:37:A1:A3 10.100.0.40
EDX 08:00:09:51:95:28 10.100.0.41

Troubleshooting

Final Vacuum

Final vacuum doesn't want to drop beyond 1.8e-5 torr. However, after leaving the scope on, the vacuum increases to around 1.3e-4 torr. Venting and pumping the chamber always fixes the problem. Also, when pumping down, the pressure bounces around a bit initially, and then suddenly drops from 1.0e-4 to 6e-5 torr within a second, which is likely a physical impossibility. Possibilities:

  • The Penning vacuum gauge can become plated with ions. This is a very common failure mode and can cause false readings. Lightly sanding the anode and cathode, and washing everything in acetone, is the manufacturer's recommended cleaning procedure. This probably hasn't been done in a very long time and is a good first step before further troubleshooting. For all we know, we don't have a problem. Lending support to this is an absence of image degradation between the 1.3e-4 "bad" state and the 3e-5 "good" state after venting and pumping.
  • The vent solenoid has been known to leak on other SEM users' scopes.
  • Chamber and gun gaskets should be greased with a suitable high vacuum grease, e.g. Apiezon M.
  • Rotation speed on the turbomolecular pump can be checked, which correlates to chamber pressure.

Image Processor board loses communications

We have observed after moving the scope to its new location that the vacuum spontaneously shuts off. Error messages pop up on the console several seconds later concerning timeouts to the Stage and Vacuum board.

Communications between boards happens via RS232 over fiber optic cables. The Opto 10 and 11 connectors handle communication to the Stage and Vacuum board, and unfortunately it appears tension was applied to the fiber, causing damage to the connector on the image processor board. The cable isn't locking in place properly.

On a single occasion, communication to the EHT board was lost. This corresponds to Opto 8 and 9.

A dual cable plugs into a single port, Opto 1, for the HRRU pixel data. The fiber plug connector on the cable end has snapped. This is not critical as we are not using the HRRU.

Repair is possible. The connector in question is a "hp 9534 R-2521" with a T-2521 next to it. These appear commonly available, but soldering to the image processor board should be considered a last resort.

Maintenance Log

Date Maintainer Description
4/7/2014 Ryan Pierce Discovered that tension on the HRRU fiber cables snapped the HRRU fiber connector of one cable and damaged the locking mechanism on OPTO 11, which likely caused the loss of vacuum and loss of communication to the vacuum board. Removed the HRRU cables so they are no longer a hazard. Re-seated all fiber connections to the image processor board.
3/6/2014 Ryan Pierce Replaced vacuum mist and odor filter, D ring, and drain plug gasket. Replaced front panel standby light bulb.
3/2/2014 Ryan Pierce Changed CUTCP CONFIG.TEL file to use hard-coded DNS because the new router does not send DNS info with BOOTP responses.
1/7/2014 Ryan Pierce Noticed HDD controller error. This has happened in the past. Physically moving the IDE cable fixes it. Moved the cable this time, and the problem went away. Suspect bad cable. So I replaced the IDE cable.
12/24/2013 Ryan Pierce Changed all user scripts to point FTP to semsrv.pumpingstationone.org so that the old server, plank, can be retired. NOTE: While CUTCP does get DNS from BOOTP, the NCSA Telnet I'm using for FTP does not! I had to hard-code the IP address of the DNS (used 10.100.0.1) in the CONFIG.TEL file which is a nasty but necessary hack.
11/9/2013 Ryan Pierce Changed rotary vacuum pump with oil that came with the SEM. Noted that the oil mist filter was dry, but not working well as a lot of odor is passing through. Needs new filter elements.
10/17/2013 Ryan Pierce SEM claimed filament had blown when this was not true. Opened gun, put same filament back. Re-aligned. This was after 6.9 hours filament time.
9/26/2013 Ryan Pierce Filament blew after 49 hours run time. Replaced.
9/12/2013 Ryan Pierce Discovered that final apertures were set at 20, 50, and 100 micron. However, the spare parts that came with the SEM only had 20, 30, and 50 micron apertures. Reconfigured dialogue box to use these values and for the #2 aperture, the image become much clearer. So this appears to be a config error I corrected.
9/2/2013 Ryan Pierce Installed NCSA Telnet (in addition to CUTCP package I already installed) because NCSA FTP supports scripted input. Set up user scripts and icons to push files for each user to the FTP server, and to delete files.
8/31/2013 Ryan Pierce Installed network software in C:\NETWORK. Set up AUTOEXEC.BAT to launch DOS networking from startup. Used EZSETUP.EXE to configure Ethernet card for 0x280, IRQ 3, 0xCC00 as recommended in Leica manual. (Note: Memory address conflicts on factory setting. Use soft config jumper.) Set up DOS packet driver. Set up for BOOTP. Networking under DOS works, and the DHCP server will respond with the appropriate static IP. Installed WINPKT.COM which is necessary to allow apps under Windows to use the packet driver. Tested apps in a DOS box; work successfully. Moved unnecessary startup items to a new group so they do not launch on startup and consume RAM.
8/30/2013 Ryan Pierce Changed from backup hard drive to system hard drive. (Backup that Jay made works. Note that he must have taken the backup when the SEM was in a weird state; you will need to load one of the configs in the default user directory just to see beam and an image. The LUT may have the colors inverted too. Reminder: have Jay make another backup once we're good to go with networking.) Removed laser printer card. Installed SMC Elite 16 Ethernet card. Set up template user directory in C:\USER\TEMPLATE and set up C:\NEWUSER.BAT script to create new users. Put sensible default settings in the Template dir.
7/23/2013 Ryan Pierce Disabled SEM option for "windowless EDX" because it seems like we don't have it and it was inhibiting the chamber from venting. Changed resolution on EDX computer from 640x480x64k colors to 1024x768x256 colors. Now it is much less annoying with little loss of function.
7/21/2013 Ryan Pierce Did full detector calibration of EDX with copper target. Also changed SEM configuration to show multi-dot EDX present, which enabled EDX presence mapping, including support for multiple channels. (Tested 3.) Noted that Isis EDX PC floppy drive failed; need replacement.
7/20/2013 Ryan Pierce Added liquid nitrogen to dewar and reset liquid nitrogen temperature sensor calibration. Demonstrated that EDX is functional.
7/14/2013 Ryan Pierce Changed EDX power supply voltage from 240V to 120V. Computer now recognizes detector. Customer self-test passed.
4/14/2013 Ryan Pierce Ran up new filament. Filament Current 2.71A is now 1st peak. Vacuum 7.5E-5 Torr. Aligned gun and aperture. (Changed to Aperture #2.) Resolution with sputtered gold looks good.
4/14/2013 Ryan Pierce and Steve Finkelman Filament blew due to vacuum loss. Replaced filament. Adjusted to 0.6mm from face of grid aperture, which is standard for longer filament life.
4/7/2013 Ryan Pierce Installed new CPU fan. Finished replacing all panels except for the CPU.
4/?/2013 Ryan Pierce Hacked CMOS battery from battery holder and 4x AA batteries. Had to change jumper on motherboard, per manual, to use external battery as opposed to on board battery. Replaced two of the three front panel light bulbs.