the Tecnai F20 User Manual - LE
Contents
1. 14 C2 astigmatism Tune condenser multifunction medium C2 intensity gt turn off condenser astigmatism and gun shift affect each other 15 Follow the Direct alignment Gun tilt Only for experienced users Not always needed at low mag make the bright spot at the center of the crossover using MF knobs X Gun shift Focus the beam and check the position of the bright spot in the halo Bring it to the center using multifunction MP knobs as shown below Py Beam tilt X and Y Make two points to one point suing MF knobs Beam shift If the beam disappears from the screen then go to low mag till you see it on the screen Use MF to move the beam to the screen center Rotation center Defocus the beam identify a feature on your sample and stop its lateral movement using MF knobs OG kS 250kx high mag It is easier to do it in the TV but you must be in EFTEM mode to use TV Focus outer big knob TV camera EFTEM Focus step innter small knob Camera for software Camera High magnification spread the beam low magnification beam shrink Check TV connection 1 cable input 2 power by Panasonic DVD Defocus the condenser and adjust the beam intensity by focusing C2 on TV monitor not on the screen to avoid damaging the CCD camera If something is wrong with the software or TEM just logoff and login again asul asul Never restart the computer 16 EFTEM EFTEM lift up the scree2. 0 100 Status Extractor time to go 111 sec 4 turbo pump 10 outlet sample pressure Meter 5 turbo pump 10 inlet gas pressure before sample 2 column vacuum sample pressure above and below sample 1 Change from TEM mode 1 to E TEM mode 2 2 Push V5 gas in and V8 by pass valve to manually open them 14 3 Close all inlets to the gas manifold open inlet from the gas to be used and let it pump out any residual gasses form the line 4 Close the gas inlet to the manifold 5 Open gas main valve regulator on the tank open second valve black valve to the manifold Fill it up to approximately 300 torr pressure and close the inlet valve and main valve regulator 6 Connect the cooling water to heating holder if required 7 Connect the holder to the hot stage power supply turn the current knob to zero counter clockwise push power and heater test it check the wire is not broken 8 Make sure gas inlet valve to the microscope column needle valve and V3 are closed clockwise 9 To let the gas in the column open V3 first and then slowly open the needle valve gauge 5 and 4 will rise adjust needle valve slowly to make gauge 5 to desired pressure Make sure that the reading of gauge 4 and 2 is not higher than 10 torr Gauge 2 should be better be 104 torr 10 Input your UIC and open the gun check FEG IGP not higher than 0 5uA V5 and V8 is the most important valve during purg
3. e System On Off Buttons Off button is lit red e Vacuum Enable Button Vac is lit white e High tension Enable Button HT is lit white On Off Oo Instructions to use the Tecnai F20 in TEM Mode High Vacuum mode CHECK 1 Check on the box hanging below the control boxes that microscope is in TEM mode i e a green light glowing by TEM sign 2 Valve 4 is closed valve 5 and 8 are open High Vacuum Mode Valve Status VO open V2 open V3 closed V4 closed V5 closed V6 closed V8 closed V9 open or closed V10 open or closed Never restart the computer just logoff asul if necessary Log in if needed TECNAI F20 log name asul password asul Use the Launcher on the desktop to start all software needed to run the microscope Startup 1 Fill the cold trap with liquid nitrogen Move the computer monitor and avoid to spraying the screen 2 Make sure HT enable is on and the high tension is on at the required high tension value If HT is down such as forget input UIC before open the gun valve push the HT button first and then high tension and operate Load your sample in the holder you want to use 4 Reset the holder and insert the specimen holder into the microscope column A Turbo pump on amp yellow light Inserting Specimen Holders e Column Valve is closed High Tension and Filament are on e Reset Holder Stage Control Reset hold
4. Click on EFTEM to bring microscope in TEM mode Go to Search gt Stage Reset Holder Click on Col Valve Close to close V4 and 7 Unload the sample and sign in the logbook Ww te kS Removing Specimen Holder e Close the column valves e Make sure the specimen holder is in a safe position set all axes to 0 by Reset Holder The red CompuStage light should be off e Pull the holder as far out of the CompuStage as it will go then rotate it clockwise as far as it will go about 120 degrees e Use one thumb hold the blue cover plate and the silver ring on the CompuStage Carefully extract the holder from the airlock you have to pull against the vacuum remaining in the airlock EELS General Setup for PEELS Energy shift depends upon the element to be analyzed generally over 100eV Dispersion 0ev channel Entrance aperture 2 mm Condenser aperture 3 spot size 6 camera length 1 75M Number 5 in the small keyboard whole EELS spectrum Acquire alt set up parameter for acquire mode Exposure 1 second bin CAUTION Do not lift the screen and start collecting EELS spectra unless you are sure that beam intensity is very low You can easily burn the CCD a ee Align ZLP and also tune GIF if you not already done so in image mode see instructions for TEM operation In EFTEM mode select spectrum imaging TIA control will ask you to defocus the beam Keep the scr
5. Tecnai F20 Operation Instruction Specifications Imaging Modes TEM STEM Accel Voltage 200K V Cs 1 2mm PTP Resolution 0 24nm Information Limit 0 14nm Source Field Emission Tilt Range 30 normal holder Tilt Range 70 special holder Ancillary Equipment CCD Camera Video Camera Gatan Imaging Filter Environmental Cell Single Tilt Heating Stage Double Tilt Heating Stage 800 C Techniques Energy Filtered Imaging Environmental Cell Microscopy EELS HRTEM Z contrast Imaging The FEI Tecnai F20 is equipped with a differentially pumped environmental cell for in situ studies of gas solid reaction kinetics and mechanisms This system can handle gas pressures up to 10 torr 1 torr 133 322368 Pascal has both heating 800 C and cooling liquid nitrogen 173_ Centigrade holders for controlled temperature studies and is equipped with a post column Gatan Imaging Filter GIF for electron energy loss spectroscopy and energy filtered diffraction and imaging 4 turbo pump 10 Meters 5 turbo pump 10 2 column vacuum 1 TEM Mode in the back of TEM 2 ETEM Tel Karl wise 5 3831 Dr Sharma 5 4541 Dr Crozier 5 2934 Tecnai F20 Operation Guides On line help is available by press F1 or click the toolbar Help in Tecnai user Interface TUD For Emegency Instructions see here Initial check Following buttons indicate the microscope is on
6. a flood 150W and 120V heating lamp to clean the grid and sample for 1 hour before the experiment 2 Cleaning of TEM column and plumbing a Check the recent users for E TEM b Bake the plumbing the day before experiment day c Purge the plumbing and e cell separately with H2 and N3 first 50 Torr Hz and then 200 No d If Karl can bake the TEM column have it done Preparation the day before the experiment day 1 Make sure the gasses you want to use are connected to the gas manifold 2 Check gas cylinder pressure 3 Check the status of various heating holders from their logbooks and choose a holder you want to use 4 For heating experiments above 500C set water cooling system See the section about Heating holders 5 Make sure cooling is water flowing through the sample rod and there are no bubbles 6 Make sure current is set to 0 on hot stage power supply CCW to zero 7 Make sure to use proper washers and hex ring The day before the experiment day baking the plumbing always and check who used the machined recently and check if there is water or carbon contamination Baking temperature about 125 C v8 is open 11 mee Read only donl off Baking the plumbing V5 and V8 is open needle valve and N gt valve open not main valve for baking the N2 plumbing line Control Box Control panel Valve Control Box Operation The five position rotary switch is used to select the desired operating mode M
7. bj astigmatism defocus to see the rings For correcting obj astigmatism set integrate time 0 25 s with binning 4 or search mode Before lift the screen make sure that the beam intensity is very weak direction to avoid burning the CCD camera 9 Underfocus counter clockwise D 10 Center of entrance to TV image Beam 10 clocks 7 T oeren 11 Quickly take the image preview change some setup N SAS E o 17
8. de diff shift to obtain the highest intensity of EELS spectrum Theoretically the diff pattern is from the same area 1 Diffraction mode defocus the shadow image Beam size Shadow image Select the eV range of interest by changing the energy shift value and collect the spectra Good luck E TEM mode operation Outlet C0 al Inlet O Needle valve to close clockwise V4 Outlet 0 Obj aperture Status and functioning of various valves Gas Purging 1 Open V5 to let gas in 2 Close V5 and open V4 and V10 may have to ramp down the turbo pump 3 Close V4 and VO and open V3 In Situ Mode 1 Open V8 2 Close V2 and open V6 3 Open V5 to let in gas 10 Back To High Vacuum Mode 1 Close V5 and V3 manual valve 2 Wait till pressure drops in AP1 and AP3 then AM2 and AM4 3 When AM2 and AM4 10 Torr open V2 and VO to allow IGP4 and IGPO start pumping column 4 If IGPs are low and not rising close V6 and V8 5 Shut down turbo and MDP Cleaning issues for a successful E TEM experiment 1 Cleaning of hex ring washers and grids a Put them in the glass beaker filled with propanol isopropanol or isopropyl alcohol semi conductor grade 99 999 Ultrasonic cleaning for half hour put under heat lamb for 60 minutes b Put them in glass container not in plastic container c Plasma cleaning the holder for half hour just before loading sample d Heat sample rod before loading Use light Sylvani
9. een down and hit return Select 1 eV channel dispersion 2 mm entrance aperture energy shift of 200 300 eV Lift the screen and click on search Focus the spectra using elemental peaks if possible If no sharp elemental peaks are present in your spectra bring the screen down reduce the beam intensity by defocusing C2 to fill entire screen and change energy shift to 0 Use Fx Fy etc in the filter control window make the zero loss peak intensity highest peak form Gaussian and with smallest FWHM Focus using zero loss peak Make sure to reset energy shift to 100 300 eV after focusing Collecting spectra 1 Select a different area from the area you want to get EELS spectrum In the diffraction mode center it to make the intensity highest 0 6mm entrance aperture search mode by moving the diff shift multifunction Use the whole EELS spectrum to see the intensity change Use entrance aperture 0 6mm to center the spectrum in the entrance aperture maximize the intensity and use 2mm more intensity to acquire You can use 3mm for more signal if 0 6mm is centered you don t need to center other apertures Find area of interest put the area at the 9 or 10 clock on the small ring on the screen so you can see the image in the TV easily Beam 10 clocks p 2 M oSer Select Object window in DM image display stop Auto high In image mode Use beam shift to obtain the highest intensity of EELS spectrum In diffraction mo
10. er e Hold the specimen holder with the airlock pin parallel to the small slit in the CompuStage front plate Close position at roughly four o clock Carefully insert the end of the specimen holder into the airlock cylinder and slide the holder in until a stop is reached At this point the pre pumping of the airlock will start as indicated by the red light on CompuStage which will be illuminated Make sure that the airlock pin falls properly into its groove Check on Vacuum Overview that the valve to column is closed and valve between airlock and turbo pump is open e The Tecnai user interface will display a message asking for identification of the specimen holder Select the type of holder from the list and press the Enter button ST Holder for FEI Single Tilt Holder ST Cryo Holder for Gatan Single Tilt Cryo Holder Caution As long as the red light on CompuStage is illuminated it is unsafe to insert the specimen holder further into the microscope The airlock pumping time starts counting when the TMP has reached the ready status again the initial opening of the airlock causes it to lose speed and so drop out of the ready status If the LED doesn t switch off after the airlock pumping time plus some seconds for the TMP to reach ready status there very likely is a leak In that case remove the holder and wait until the system has returned to ready status and try again after inspecting the holder for possible sourc
11. es of the leak reason of condenser astigmatism e When the red CompuStage light has been switched off rotate the specimen about 120 degrees counter clockwise as far as it will then allow it to slide in further into the microscope Caution Maintain a firm grip on the holder while it is sliding in it is being sucked in by the column vacuum to safeguard against any possible damage to CompuStage or holder Once the holder is fully in carefully tap a few times with a finger against the cap of the holder to help it settle into position and thereby improve stability Turn off the turbo pump manually by clicking the sign Turbo Pump Switch the filament on to the required setting Do not change the setting Check the vacuum Tecnai G Vacuum Overview If IGP 1 lt 15 input your UIC and open column valve yellow close gray open The beam should be now visible IAM If you have not logged off the previous user then make sure microscope is not in EFTEM mode Do the alignment in TEM mode not in the EFTEM mode Deselect EFTEM mode b clicking on EFTEM sign Tune Direct Alignment 1 Reset Defocus L2 ScreenDim L3 Spotsize 1 Screen lift R2 Toggle up np R3 Spotsize FX image shift X FY image shift Y Search gt MF knob Rotation center 250 kx Coma free Alignment x Coma free Alignment y Coma free pivot point x Coma free pivot point y Off axis shift TV Direct Alignments Find t
12. he beam Center the beam by the Beam Trackball ERERER LP 9 Eucentric focus Specimen height Z height e Set Mag to 10k x spot 3 or 4 shift specimen into the field of view e Press Eucentrical Focus button RP e Stage Control Alpha Wobbler 15 minimize the side way motion of the image with Z Axis Height control RP e Click on Alpha Wobbler again to quit 10 Rotation Center e Set Mag to 30k x shift an image mark to the center of screen e Goto workset Tune gt Click on Condenser click on one of the three channels Center the beam by Beam Trackball LP and spread the beam by Intensity LP e Minimise the image shift by adjusting Multifunction X Y knobs LP and RP e Click on Done in Workset to quit the rotation centre correction 11 Focus Low mag Find a recognizable feature from your sample Start specimen wobbler search wobbler reset stage Change the Z height to stop the lateral movement of the feature High mag 125k focus the condenser change the Z height in positive or negative direction until diffraction ring disappears or change Z height tab not push continuously to obtain minimum contrast 12 Spot size 1 C1 its function is to create a de magnified image of the gun crossover and control the minimum spot size obtainable in the rest of the condenser system the largest and brightest spot size is 1 For HREM images spot size 3 is a good compromise 13 Center the condenser aperture CW and CCW
13. ing Increase temperature repeat gas filling adjust temperature until balance a purge plumbing First with H2 and then with N gt easier one Close V3 black valve and metal needle valve Fill mixture gas tank less than 660 torr Slowly open metal needle valve and observe the Meter 4 and 5 V3 close V5 and V8 open for purging plumbing Meter 4 plumbing line front part 7 5x 10 limit if higher it can t tell Meter 5 plumbing line back part 1 07x10 limit for N2 b purge TEM e cell V3 and V5 open and V8 close 1 Close V3 E TEM mode V5 and V8 open 2 Fill the gas manifold with N2 and or H2 up to 660 Torr 3 Close needle valve and V8 open V3 and slowly open the needle valve until all the gas from manifold is pumped out close needle valve 4 Repeat steps 1 3 twice Setup is over Good luck Some tips 1 Hp is the most difficult gas to vacuum so normally use H2 N2 mixture 15 In ETEM mode before open gun valve the check the reading of gauge 5 is 8 Always keep an eye on the FEG IGP current when in ETEM mode Keep carefull records of time temperature and pressure during entire experiment Make sure the cooling water is flowing through using the heating holder rod all the time When increase the temperature decrease the magnification to 52000x to avoid loosing the sample area due to drift 7 Record the tank pressure and gauge 5 readout all the time DUN E TEM Shut down 1 Close V5 V8 c
14. ion for oxidation check the connection envision and inspection gt Hexaring inconel 7 Washer inconel Heater 0 7 C D Sample Pt j xov Washer inconel Thermocouple 34 G03 holder single tilt holder after the experiment record in two logbooks current temperature Load sample single tilt holder special tool big ring to avoid twisting the metal wires reduce the stress sandwich sample to avoid melt and contamination 13 Hot stage control plug for the power of holder Gatan hot stage power supply connect the stage to hot stage power supply Cooling water use gallon bottle to fill the upper barrel and connect with hot stage Put the stage cover on It is advisable to obtain the gas pressure in the E cell before staring heating in order to avoid cooling of the sample and drift due to gas flow Pay attention to FEG IGP current lt 0 5uA when gun valve is open this is very important Check gun IGP current When the gun valve is open especially there is gas flowing and higher temperature check the gun IGP current and IGP2 vacuum if the current is higher than 0 5uA immediately close the gun valve Gun runs normally above 10 torr FEG Control Expert Options Operate Gun lens 3 ower Cold Star Yarmi Start Extr voltage 3000 a Extraction 3150 V z 7 Extractor limit FS 4500 a 3000 4000 FEG Emission 31 uA FEG IGP Current e nr a R E TE a A Output
15. lose is ok pump all of gas out of the e cell 4 and 2 at 5 10 torr 2 Remove specimen holder Close V3 change E TEM to TEM open V5 and V8 pump all of gas out of the plumbing and mixing tank 3 Purge the plumbing and the column with nitrogen gas 4 Sign the two logbook general and hot stage logbooks Login You need a Tecnai 12 account and a password Logoff When you finish your session you must logoff the PC Do not select Shut down because that will effectively shut down the microscope preview Cameras search turbo _ continious acquires sin gle 16 Hot stage Two wires for heating two wires for thermocouple alumina furnace Gy Securing Plate O rings i C gt hexaring Windowed TEM Grid CD washer Coa sample Caa washer NOY Amorphous carbon film Two inner wires for heating Two outer wires for thermocouple E Condenser astigmatism Some tips for TEM operation 1 Ifthe column vacuum is down when you change sample wait for IGP1 lt 15 then add HT and operate FEG current Plasma cleaning put the holder in vacuum power on clean and set the time turn off and take the holder out If you turn on high tension need waiting about 5 minutes then click on operate FEG register set the saved setup to load good alignment it works only logoff and save it Focus eucentric focus Z height to vanish the diffraction ring TV to focus Before correcting for o
16. n TV image Decrease the intensity Focus the sample carbon film in the TV image Find a large hole in your sample and center it on the screen Click on Align ZLP Zero loss in the hole Click on Tune GIF takes several minutes in the hole Move the sample in Click on CCD preview Camera to obtain image on CCD camera focus You can use multifunction for fine movement of the sample spread beam on the screen lift the screen focus the beam and sample on TV Gain reference in DM If needed In image mode perform ZLP and tune Gif alignments middle is green and use small keyboard enter Prepare gain reference Image mode 5mm hole in screen Center the hole in TV TV out lift screen and answer questions kS oe kS kS we e Me 17 Correct the objective lens astigmatism Camera Set camera for continuous exposure binning 4 0 25 sec exposure time for search binning 2 0 5 sec exposure time for Preview and single frame binning 1 1 sec exposure time for Aquire Select search or preview to obtain an image on CCD Select Process gt Live gt FFT in Digital Micrograph DM Tune Obj Stig using multifunction make it round use focus to adjust the size of circle Correct the objective lens astigmatism underfocus obj lens bright edge to get rings Correct the astigmatism by using MF knobs and make the rings round Co
17. ntinue the process after changing focus one step at a time until a single perfectly round ring is observed at Sherzer focus Objective lens CW overfocus black edge CCW underfocus bright edge FEG condenser lens overfocus objective lens underfocus Carbon film v m a To correct for the obj astigmatism first adjust the focus to obtain rings in FFT image and then make the rings round by adjust the obj astigmatism using MF knobs OSES Objective astigmatism using FFT Bad astigmatism showing a distorted FFT at a underfous b at focus c overfocus Good Astigmatism showing round FFT at d underfocus e at focus f overfocus since you can see a Slight shape difference between under and over focus FFT there is actually still a little astigmatism You can correct objective astigmatism using Digital Micrograph to view a live FFT of an amorphous area of your sample The area chosen to do a live FFT must be fairly uniform and all amorphous Adjust the objective stigmators to make the FFT round You can select a small portion of your image using the dotted square selector tool with the option or alt key held down Diffraction astigmatism correction Astigmatic No astigmatism For best results correct for objective astigmatism right before recording images as near the sample area of interest as possible Fine tuning will be required from time to time throughout the session Enjoy Shutdown Procedures
18. ode 1 TEM Mode 2 ETEM Mode 3 VENT Mode 4 PUMP OUT AFTER PURGE Mode 5 START SHUTDOWN 12 Once the desired mode has been selected the black button in the upper right corner MUST BE PRESSED in order to make the control box open close proper valves for the new mode The push button switches are for manual control of a specific valve If the green LED below a switch is illuminated manual control is allowed Pressing a button while the LED is illuminated will cause the valve to go to the opposite state The three red warning indicators flash when an emergency or over pressure is detected As of this writing they are not yet active After the baking the plumbing Day of the Experiment 1 Select appropriate holder load you sample and align the TEM EFTEM using instructions given above 2 Make sure all the inlet valves to the gas manifold are closed For all of the valves clockwise turn is to close the valve 3 Make sure any water precursor containers attached to the microscope gas inlet are closed 4 Select ETEM mode on the control system Open Valve 5 and 8 manually DONOT USE ANTICONTAMINATION DEVICE Liquid N2 trap in ETEM Mode Heating Holders There are four heating holders available and each holder is clearly marked Pay attention to the loading instructions washer and hexring material for the holder you choose for your experiments IDT is double tilt hot holder check thermocouple and heating wire connect
Download Pdf Manuals
Related Search