Technical ObjectiveSlide 2Leo 440i SEMLeo SEM: rear of columnEDS side of SEMSlide 6Administrative mattersNotes on the computerGetting started with the LeoSample MountingTo insert your sampleSlide 12Drop Down List Box and Tool Bar (nearly all SEM functions are mouse-controlled)‏Go!Decide on operating parametersSlide 16Slide 17Pictoral explanation of gun shiftSlide 19Adjust beam shift when OptiBeam is turned onVoila! An image!Optimize imageSaving an imageSlide 24Saving images, cont’dSlide 26LEOTechnical Objective•To train you to use the electron microscopes on lower campus•Start with the Leo 440i–We control it!–It’s currently running–Once you have learned the concepts on one microscope, in principle everything else is “knobololy” (Figuring out where the knobs are that control the feature you want to use.)–It’s not easy or expensive to break (please don’t prove me wrong!)LEOVac-ion PumpColumn“Upper Valve”Chamber10-3—10-7 TorrColumn ValveElectron gunTurbo-molecular pump10-6—10-8 Torr760—10-3 TorrStageSamplePenning gageOil FilterExhaustPumping system for Leo W-filament SEM (actually LaB6)Oil-sealed Rotary Mechanical PumpLEOLeo 440i SEMColumnElectron gunAperture adjustment micrometersChamber valveUpper valveTurbomolecular pump behind hereLEOLeo SEM: rear of columnVac-ion pumpEverhard-Thornley DetectorGunLEOEDS side of SEMLN2 tankBeam blankerLEOOil-sealed rotary mechanical pumpLEOAdministrative matters•Nothing in life is free•Log onto the SEM with the sheet on the desktop•Enter your name•Enter the name and contact information of whoever will be paying•Record how many times you coated samples•Click on “View/Status”. Enter the filament lifetime when you start.•Enter the time of day when you start.•Repeat the last two steps when you finish.LEONotes on the computer•The SEM is about 15 years old. It runs on a 66 MHz 486 under Windows 3.11.•Plan on having to reboot at least once per day.•In windows 3.11 you cycle among active applications with ALT TAB. (Hold down ALT; every time you hit TAB, it cycles one application.)LEOGetting started with the Leo•Typical conditions when you walk in:–Ion pump is running–Chamber is under vacuum–“Upper valve” (gun valve) is closed–Column valve is open–All pumps are runningLEOSample Mounting•Leo uses mounting stubs with 1/8” shafts•Carbon tape (double sticky) is simplest•Carbon dots have lower vapor pressure•Multiple samples can be mounted on turret•Make a drawing in your research notebook of the locations of your samples on the turret•Single mount is easiest for tilting•Vertical mount is also an option•Tighten gently with Allen wrench; ditto for sample holder on stageLEOTo insert your sample•Check vacuum–Stage/vac–Vacuum status•Chamber pressure should be 10-5 – 10-6 Torr•Column pressure should be few x 10-7 Torr•Close column valve•Vent (Stage/vac, Specimen change or right yellow arrow)•Insert sample. Remember where samples are!•Close and latch door. Do not overtighten!•Pump (Stage/vac, Specimen change or right yellow arrow)•After the pressure goes below 10-4 Torr you may open the column valve and turn on the beam.LEOLEODrop Down List Box and Tool Bar(nearly all SEM functions are mouse-controlled)Beam onBeam offStandbyPumpVentVacuum controlLeft mouse button Middle mouse buttonRoll mouse left to decrease valueRoll mouse right to increase valueAlternatively, double click on a box to enter data directlyLEOGo!•Turn on beam•Turn up brightness •Hopefully you will see something•Optimize beamLEODecide on operating parameters•40 kV for highest resolution•20 kV for EDX•Low voltage for optimum topography and least damage•100 pA for good resolution•300 pA for EDX for better signal-to-noise•25 mm WD for EDX•7 – 8 mm WD for maximum resolutionLEOCenter of Stage (Red square)Beam location(Blue square)Cursor!Stage will move in direction of arrow when left mouse button is depressedSpeed increases with distance cursor is from beamLEOUse when OptiBeam is offOptiBeam onLEOPictoral explanation of gun shiftFilimentGun tiltlenslenslensaperatureWith the gun shift centered, the electron beam heads straight down the column. The image is brighter and can also be focused better. Otherwise the image moves when you change focus.LEOCenter filament image with “Tilt” optionLEOAdjust beam shift when OptiBeam is turned onLEOVoila! An image!LEOOptimize image•Start with low magnification•Look for dirt or some feature•Move feature to center of screen•Go to reduced raster•Focus•Increase magnification•Focus•Iterate•Full screen imageLEOSaving an image•Get good quality image–2 minute scans over a few kX–Faster scans at lower magnification•Under “Image/Noise reduction”, click on “Freeze at end”LEOLEOSaving images, cont’d•Under “File/Export tiff”, choose e:\ as the destination. The E:\ drive is mapped to the support PC that is next to the machine. From this machine you can use a USB memory stick or transfer files through the internet-- web mail or file transfer.•Enter a filename: 6 characters (related to your sample) + 2-digit counter (00)•All students need to bring their own USB stick; files are approximately 1 MBLEOCheck “Export/Photo setup” to assure it is not set to