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*Manual #1019 Titel

1. counterclockwise while holding the adjusting ring Fig 6a in its position Pull out the broken filament from the socket with a tweezers Carefully insert the new filament with the tweezers The filament has to be inserted tightly and has to be pressed closely to the teflon seating Fig 6b Fig 6 Carefully screw the Wehnelt cylinder clockwise over its base until it softly con tacts the adjusting ring Primarily this ring should not be moved Correct position of the Wehnelt is achieved when the tip of the filament can just be seen within the aperture of the Wehnelt cylinder at a viewing angle of about 45 Fig 6c A necessity to readjust the height of the Wehnelt may be indicated by lack of adjustability Wehnelt voltage when turning the Wehnelt knob 3 2d or poor CL emission together with low current voltage Poor emission and weak current voltage are indicative of a too high situated Wehnelt cylinder whereas lack of adjustability occurs when the tip of the fila ment reaches too high that means the Wehnelt is situated too low Readjustment of Wehnelt height to its correct position see Fig 6c is done by turning the adjusting ring to the respective direction and bringing the Wehnelt again into soft contact to it until the position of the filament is right Take care that the tip of the filament is situated right in the centre of the aperture of the Wehnelt cylinder to obtain maximal homogeneity of the electron bea
2. Maximum speed of the turbo pump is reached at 58 Krom digital indication at the pump stand Wait until the vacuum pumps will have reached working vacuum within the sample chamber is reached from ca 5x104 mBar and the color of the small number 1 in the vacuum meter has shifted from red to green indicating that the vacuum is close to ready and the high voltage can be activated presets of the vacuum meter must not be changed Note If the device is started after an out of operation period you should con tinue evacuating for at least 30 minutes before going on enhances quality of vacuum and enables function of measuring tube Manual 4 A6 Turn on main switch 3 1a of the casing for the power supplies HC5SLM SG lt groundcable to stand of microscope gt lt A8 red switch lights up Power Supply Rack HC5 LM rig 3 KK HC5 LM SG 3 1a Vac only 0 O O O Deflection Focus Beam 3 1b 3 1C 3 1d KK HC5 LM EQN N E r Filament Wehnelt 3 2c 3 2d Filament current 3 2b Never operate without connected groundcable o Filament On Heinzinger LNC 20000 3neg nee 0 1 0 1 4 0 0 R p a 9 3D 7 3 3e A MA Current KV o o A O max 14 kV O 3 3d Voltage HV Output 1019 Be sure that the toggle switch Ext Int at the digital outlet of the high voltage power supply 3 3 is set to Int prefi
3. are cotton swaps cosmetic tips small wooden pins and cloths Scratching or grinding tools like screw or knife must not be used at all After polishing the cylinder has to undergo ultrasonic cleaning with acetone for about 10 minutes to remove the remaining fat and wax Ultrasonic cleaning should be once repeated with fresh acetone The large O ring seal of the vacuum chamber should be cleaned occasionally and thinly coated with vacuum grease From time to time the leaded glass in the cover of the sample chamber should be cleaned with a soft paper soaked with acetone Leaded glass is distinctly softer than normal glass so do not use any scraping tools After longer time of running a layer of dirt may have deposited on the brass parts of the sample stage and the aperture compare Fig 4 To remove this coating the sample holder can be taken off and ultrasonically cleaned with acetone for about 10 minutes The sample holder stage has not to be dismantled clean it with cotton swaps soaked in acetone If the aperture in the bottom of the sample chamber is strongly polluted which will occur after very long time of running only it can be dismantled with the delivered special tool To reach the aperture first remove the sample stage After taking off the sample holder turn the right grub screw as far as possible out of Manual 10 the sample holder stage the stage moves towards the left Screw off the long guide way and take off
4. Cathodoluminescence Microscope HC5S LM User and Service Manual October 2009 Ne 1019 lumic www lumic de lumioc special microscopes Dr Maria Simon Neuser Plasshofstrasse 11 44795 Bochum Germany Manual 1 Contents MOOOC HOU 5 eccnyasynotondadanncetnanaveaspesunssycoud E EA 2 A Sher UG he SY CC as pco ees eesteseatiac nE EEA NEE EE EEE EERE RES 3 D eI CIA OS e a E E O ene eco deceasaodsdeseaes dectecce ses 5 C Adjustment of the electron beam 2 0 ec cccceecceeccc sees eeeeeeeeeeceeeeaeeeseeseeeeaeesaeeeas 6 D CANIS Or TNA ICING ee atconcaemrecemnnangaunncs cenewanedenc te E E 7 E SS INC ING ON eerie a E 9 F Maintenance and care cccccccccceccscceeeceeceeceeeceeseceesseecgesseeaeeceeteeeeeeseeseeseeeeees 9 G Hints for taking CL DPiICIUTES vos ccdccceccciwnndantcanddanidsacenadeereottaauescbacsdenasietsdannedeseseheecs 10 H Consumption material and sources of supply cccecceeeeeeeceeeeeeteeeeeeeneeeaeees 11 tellan lens Du lt q basis microscope gt L analyzer f lt _ sample chamber _ __ _ _ _ _ gt deflection coils prechamber with flanges to turbo pump E N focussing coil i 2s E polarizer electron gun LED lamp house gro
5. he right or left side Voltage of the coils is tuned by potenti ometer 3 1b of the power supply for the coils common values are about 8 Homogenization of the electron beam This can be obtained by changing the voltage of the Wehnelt aperture Tuning is done with the potentiometer 3 2d of the power supply EQN for the electron gun standard position is about 300 on the scale of the potentiometer Turn the knob 3 2d until the beam spot is homogeneous at maximum intensity The scale of knob 3 2d should be at values between 200 600 then These settings have to be re adjusted with increasing age of the filament and also at every filament change Focusing of the electron beam Varying the voltage of the focussing coil Fig 1 results in contracting and ex panding of the beam Standard value is about 12 V it is tuned with the potenti ometer of the power supply for the focusing coil 3 1C Caution Too strong contracting of the electron beam may cause partial overheating of the sample and could result in a damage of the thin sec tion At worst case the vacuum window of the sample chamber cover might break D1 D2 D3 Change of filament The filament hot cathode is subject to wear and break dependent on the quality of the vacuum and cleanness of the samples Typically it burns out after 10 to 30 hours of running and has to be replaced A fused filament can be recognized by both lack of luminescence and indication of 0 A a
6. m If the tip of the filament is strongly out of center it might be use ful to put it into its socket the other way round Put the electron gun back to its casing and close the bayonet joint Evacuate and engage the device according to the instructions of A4 A9 Wait at least 15 minutes before turning on the electron beam HC5 LM Manual 9 E Switching off E1 According to the paragraph of sample change take out the sample and close the sample chamber B1 to B4 Evacuate the device switch 2a at the turbo rack If the CL is in daily use you should keep it under vacuum permanently over the weekends too The pumps are made for sustained continuous operation Only if the device is not operated for a longer period of time pumps can be switched off E2 Turn off main switch 3 1a light is off E3 Switch off the external plug board F Maintenance and care Cleaning of the vacuum chamber The internal parts of the cathode device which work with high vacuum conditions sample chamber electron gun etc must not be touched with fingers Use non fuzzing cotton gloves Fouling at the internal surface may contaminate the vacuum system completely and thus worsen the vacuum and support the consumption of filaments The Wehnelt cylinder within the electron gun compare Fig 5 should be cleaned to shining with chrome polish WENOL or similar at about each tenth change of fila ment For dismantling see chapter D Tools for cleaning
7. ment current i e the temperature of the filament with the potentiometer 3 2c The beam current limit value is preset to 0 45 mA This is revisable by pressing the button Preset 3 3b to the left of the display usually there is no need to change If the max beam current is increased to values much higher than 0 45 mA the thin section may be damaged by overheating You may recognize the response of the current limitation by the just lighting up of its yellow indicator LED diode left to the potentiometer 3 3c Current threshold must not response during standard operation as in that case the accelerating voltage does not reach its rated value High voltage is pre adjusted to 14 kV and normally should not be changed If temporarily another only lower accelerating potential is required it may be ad justed by the voltage potentiometer 3 3d of the high voltage power supply The high voltage value during standard operation is 14 kV Higher accel eration potentials must not be used as this may damage the unit and would not be an advantage in observation anyway Additionally at bad vacuum flash overs inside the electron gun could occur To optimize the luminescing spot on the sample following tunings should be done while regarding carefully both the sample and the measuring devices Moving the luminescing spot to the right or left By changing the voltage of the two deflection coils Fig 1 the electron beam can be moved to t
8. o the CL shining may bother HV is turned off using key 3 3a at the HV Power supply and turned on again when returning to CL mode HC5 LM Manual 3 A _ Starting the device A1 Switch on the external plug board switch lights up WARNING Before turning on the plug board it is absolutely necessary to check the earth connection especially the cable between the microscope stand and the contact at the power supply rack 3 2a A2 For inserting the thin section raise the microscope head completely and care fully take off the cover of the sample chamber The cover is sucked at vacuum and loose when vented Take care that the lead glass window does not touch the objectives and avoid any dirtying of the sample chambers rubber seal and seat A3 Insert the thin section with its upper side down the span springs must not be strained see Fig 4 Put on the sample chamber cover A4 Check the on off switch of the rotary pump DS 302 2b should always be on Now turn on the vacuum system 2a The rotary and the turbo pump start and the fan of the turbo pump runs to sample chamber Fig 2 turbo pump amp rotary pump exhaust o VARIAN VARIAN DS 302 Turbo V 301 AG o oj o A5 The vacuum meter in the power supply rack 3 1d indicates growing vacuum by changing to lower pressures
9. pot by the electron beam is inhomogeneous the beam has to be ad justed additionally see chapter C Sample change Turn off the electron beam First switch off the high voltage by pressing the but ton HV On Off 3 3e the red HV LED light dies Then turn down the filament current potentiometer 3 2c to its leftmost position and switch off the power supply for the electron gun switch 3 2e Turn off the vacuum pumps 2a The pumps stop and the device is completely vented after about 2 minutes Raise the microscope head completely and carefully take off the cover of the sample chamber If it cannot be removed it will take more time to wait until the chamber is vented and the cover is loosely When removing the sample cham bers cover do not let the lead glass window touch the objectives and avoid any dirtying of the sample chambers rubber seal and seat Carefully remove the old and insert the new thin section upside down with the Sample Chamber Fig 4 Sample holder with holder stage below Span springs sample side towards the electron beam coming from below without straining the span springs Put on the cover of the sample chamber Start the vacuum pumps 2a and proceed as described in Ad A9 N HC5 LM Manual 6 C1 C2 C3 Adjustment of the electron beam A proper adjustment of the beam current is between 0 1 and 0 4 mA meter 3 3c of the high voltage power supply It can be changed by varying the fila
10. seeeseeeseeeeeeseeeeeeeeeess 3 Fig 3 Casing for low and high voltage supplies with sub racks 4 3 1 Vacuum control and power supplies for coils top rack 3 2 Power supply for the electron gun central rack 3 3 High voltage power supply base rack Fig 4 Internal view of the Sample chamber cccceeceseeeceeeeeeeceeeeeeeeaeeees 5 Fig 5 Internal view of the electron gun ssnnnnnnnnnennnnnennrnnnnnrnrsnrrnrrnrrnrrsrrennne T FO CNE aen ee E 8 Figures 2 and 3 show numerical markings referred to in the text In the schematics of the casing for the power supplies the controllers and measuring devices of each sub rack are marked with the figure number and additional characters in the respective drawings e g 3 1a for the main switch of the casing This combination of figure number and character will be used throughout the manual to designate the specific devices Hint Sample movement in the chamber is done with the brass knurls at the backside of the chamber Observation of the thin section sample in the vacuum chamber can be done using transmitted light crossed polarizers and CL Take care that at CL observation the analyzer is extracted absorbs too much light The power supply of the lamp house has a quick off switch on the right front for a fast change between CL and transmitted light with going CL Only at bright CL emissions you may wish to switch off the CL in transmitted light to
11. t the meter for the filament current 3 2b see Fig 2 for the construction of the electron gun Tools used for the change of filament are hexagon hole Allen wrench 1 5 mm tweezers not fluffing cotton glove all contained in provided small box Turn off the electron beam At first turn off the high voltage by pressing the but ton HV On Off 3 3e The red HV LED light dies Then turn down the filament current potentiometer 3 2c to the left to stroke For safety reasons be sure to turn off the main power supply switch 3 1a the light of the switch is extinct Stop the vacuum pumps 2a and wait for about 2 minutes until the system is in air Keep hold of the upper part of the electron gun and remove the lower part by a short turn to the left of the bayonet joint see Fig 5 Pull out the lower part without touching the upper part with the Wehnelt cylinder If the change of fila ment takes place during a working session the hot gun has to cool down a bit Fig 5 Electron Gun t7 internal thread Payonet joint a to microscope filament adjusting ring anode zi ess a wehnelt cylinder filament socket Important The internal parts of the electron gun must not be touched with your fin gers Always use the not fluffing cotton gloves supplied Soiling the gun results in problems with the vacuum and increasing wear of the filaments D6 D7 D8 D9 SA HC5 LM Manual 8 Unscrew the Wehnelt cylinder
12. the stage Loosen the clamp of the long thread and the milled screw and put the long threat slightly towards the outer side Now the aperture is accessible and can be dismounted and cleaned as described above Maintenance of the vacuum pumps The rotary pump always must be filled with oil according to the manufacturers in structions Regular change of oil is important For details see the manuals of the manufacturer Varian in the document folder If the pumping device does not reach its final vacuum this may be due to a leak Check at first the seals of the sample chamber and of the electron gun Even indis cernible fouling or injury of the o ring seals may drastically reduce the quality of the vacuum G Hints for taking CL pictures Take off the monocular tube by loosening the brass screw and mount the CCD camera with the already attached C mount adapter Switch on the PC and wait for about one minute until the IP addresses are fixed Start the Kappa Camera Control KCC from the notebook s or the PC s desktop and proceed as described in the Kappa manual White balance has to be done at transmitted light mode color temperature of the LED is suitably for CL too HC5 LM Manual 11 Consumption materials and sources of supply Filaments Agar A 054 for CAMBRIDGE LEICA PLANO W Plannet Tel 49 0 6441 97650 Ernst Befort Str 12 Fax 49 0 6441 976565 35578 Wetzlar eMail plano plano em de Germany Vacuum system Rotar
13. unding cable We cannot exclude any error and change in this manual Manual 2 Introduction The cathodoluminescence microscope HC5 LM enables excitation of luminescence on the surface of a polished thin section by electron bombardment This lumines cence is dependent on the material characteristics of the excited solid chemistry crystal structure lattice defects and others To avoid electrical charging of the sam ples they must be coated with a conductive layer This may be either a gold or car bon coating The geometry of this microscope implies that the luminescing surface is observed from backside through the sample holder and the whole thickness of the thin section This means that especially with fine grained samples the quality of the observed image can be improved by lowering the thickness of the thin section lt 25 um The quality of the observed and taken image can be largely increased by polishing both sides of the thin sections i e the backside is polished before fitted to the glass As the device works in part with dangerous high voltages it has to be operated with extreme care by skilled personnel Maintenance and care of the device should be accomplished likewise very conscientiously This manual includes the following schematic drawings Fig 1 Basic components of the CL MICrOSCODPE ceceececeeeeeeeeeeeeeeneeeaeess 1 Fig 2 Vacuum pumping system cccc cece eeeceeeeeeceeeseeeeee
14. xed For further information see Heinzinger manual At a vacuum value of ca 5x104 mBar vacuum is ready number 1 at the vac uum measuring device glows green the power supplies for the cathode 3 2 and the high voltage 3 3 are automatically activated Now the Power LED at 3 3a of the Heinzinger power supply rack 3 3 glows orange Switch on the high voltage by first pressing the key On Off 3 3a Power LED changes to green and then HV On Off 3 3e red LED lights up The cathode now is at high voltage 14 kV max potentiometer 3 3d Now the filament current may be adjusted For starting the Wehnelt knob 3 2d should be at values around 300 fine adjustment may be done later see chapter C2 Turn on the filament power supply 3 2e Now while watching the sample through the microscope tube with 5x objective slowly turn potentiometer 3 2c A9 B1 B2 B3 B4 B5 Manual 5 to the right until the desired intensity of luminescence is achieved The left meter of the high voltage power supply 3 3c should indicate a starting value of up to 0 2 mA and depending on the sample s CL can be decreased or in creased pre adjusted max current of 0 45 mA should not be exceeded The meter for the filament current 3 2b then should indicate a value of lt 1 6 to 2 7 A this value decreases with increasing age of the filament Too high filament currents may overheat the sample and break it If the s
15. y pump Rotary vane fluid GP type 11 No 9499390 Oil mist eliminator DS No 9499395 Oil filter replacement cartridge No 9499394 Ordering address for vacuum components and support Varian Inc via F lli Varian 54 10040 Leini Torino Italy Tel 39 011 997 9 111 Toll Free 00 800 234 234 00 Fax 39 011 997 9 350 Hours 08 00 to 18 00 Central European time vtt customer service varianinc com vtt technical support varianinc com Measuring coil and switching device MKS Denmark ApS Ndr Strandvej 119G DK3150 Hellebaek Phone 45 44 92 92 99 mksdenmark mksinst com

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