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Scanning Magnetic 

Microscope 

Model SMM-770

 

 

Operating Guide 

TRISTAN TECHNOLOGIES, Inc 

San Diego, California 

USA 

 

 

www.tristantech.com

 

Summary of Contents for SMM-770

Page 1: ...Scanning Magnetic Microscope Model SMM 770 Operating Guide TRISTAN TECHNOLOGIES Inc San Diego California USA www tristantech com...

Page 2: ...croscope System TRISTAN TECHNOLOGIES Page 2 Operating Guide for Single channel HTS SQUID microscope Model SMM 770 Option 77P 77V 77T 77B 77HR MS 770 TRISTAN TECHNOLOGIES Inc San Diego California USA C...

Page 3: ...any means electronic mechanical photocopying recording or otherwise without prior written permission of TRISTAN TECHNOLOGIES Inc TRISTAN TECHNOLOGIES Inc reserves the right to change the functions fe...

Page 4: ...original warranty plus the time between receipt of the instrument at TRISTAN TECHNOLOGIES and its return to the owner This warranty is limited to TRISTAN TECHNOLOGIES products that are purchased direc...

Page 5: ...TALLATION AND OPERATION 17 2 3 SAFETY PRECAUTIONS FOR HANDLING CRYOGENIC LIQUIDS 17 2 4 GENERAL INFORMATION 19 3 SENSORS AND CONTROL ELECTRONICS 20 3 1 WIRING DIAGRAM 20 3 2 SENSOR INITIAL PERFORMANCE...

Page 6: ...TY 59 6 6 OPTION MS 770 TWO LAYER MU METAL MAGNETIC SHIELD 59 7 APPENDICES 62 7 1 THERMOMETRY AND COOLDOWN 62 7 2 CALCULATING B FIELDS 63 7 3 WIRING AND HARDWARE CONFIGURATION 66 7 4 BACKGROUND SUBTRA...

Page 7: ...4 2 Main panel after system start 32 Figure 4 3 Track parameters 33 Figure 4 4 Preview of track to be used for discrete scanning 34 Figure 4 5 Preview of QuikScan continuous track 35 Figure 4 6 Manua...

Page 8: ...em with 5 5 Gauss external applied field Gain x100 58 Figure 6 7 Noise spectra of SMM 770 system with 5 5 Gauss external applied field Gain x20 59 Figure 6 8 MS770 mu metal shield engineering drawings...

Page 9: ...es that Whereas equipment subject to a pressure of not more than 0 5 bar does not pose a significant hazard due to pressure whereas there should not therefore be any obstacle to its free movement with...

Page 10: ...Scanning stage X y tilt stage Vibration Isolation table iMAG SQUID control electronics1 motion control hardware and software data acquisition hardware and software and a computer system note some opt...

Page 11: ...CROSCOPE SCANNING STATION Z AXIS MANUAL Z AXIS DIGITAL READOUT X Y MICRO TILT STAGE SPACER PLATE OPTIONAL SQUID WINDOW VIBRATION ISOLATION AIR TABLE ACTIVE DAMPING 3 UNITS VIBRATION TABLE TOP X Y AXIS...

Page 12: ...with a tag on it identifying yourself as the owner Please enclose a letter describing the problem in as much detail as possible 1 2 REPACKING FOR RETURN SHIPMENT If it is necessary to return the syst...

Page 13: ...r drive model MID 7602 s n E006A6 Motion Controller cable Computer control and data acquisition system and software Dell Precision PWS370 with dual Pentium 4 2 8 GHz CPUs and 1 00 GB RAM model WHM s n...

Page 14: ...00124 o Y motorized stage 12 5 micron step Parker Daedel model 106008BTMSD4L3C2M1E1 s n 052316401A Parker Daedel model ZETA57 51 MO s n 05033000125 Manual room temperature Z stage 1 micron step Newpor...

Page 15: ...ide Parker Optical L H Switch Cable Pigtail Ended Cable drawing 2 Parker Quality Assurance Data Sheet 2 Newport Isostation vibration isolated workstation Newport Active vibration Damping system DC950...

Page 16: ...ope System TRISTAN TECHNOLOGIES Page 16 2 CRYOGENIC SYSTEM The cryogenic system includes a fiberglass liquid nitrogen dewar Figure 2 1 The sensor window gap is pre set at the factory and does not need...

Page 17: ...mainly from the following properties WARNING 1 THE LIQUID IS EXTREMELY COLD 2 THE ULTRA LOW TEMPERATURE OF LIQUID NITROGEN CAN CONDENSE AND SOLIDIFY AIR 3 VERY SMALL AMOUNTS OF LIQUID NITROGEN ARE CO...

Page 18: ...be of adequate capacity to release nitrogen vapor resulting from such heat inputs and thus prevent hazard due to excessive pressure This system has been designed to safely vent the evolving nitrogen g...

Page 19: ...ERAL INFORMATION Use caution when handling delicate fiber optic cables Do not bend smaller than a 10 cm radius Do not fill with liquid nitrogen unless dewar vacuum is 50 microns Transfer nitrogen with...

Page 20: ...Z Optical Readout Omron Pressure Gauge Pressure Sensor Manual Level X Y stage motion and Z manual CPU and Monitors Fiber Lite Light source Motor Drivers IMag control Active Vibration Control F O F O G...

Page 21: ...Model SMM 770 Scanning Magnetic Microscope System TRISTAN TECHNOLOGIES Page 21 Figure 3 2 SMM770 detailed wiring diagram...

Page 22: ...flux transfer function nT o and noise pT Hz was determined The test results of the supplied SQUID sensors are shown in Figure 3 3 as a function of frequency and are listed along with sensitivity infor...

Page 23: ...ystem Parameters IFL 301 H S N 2020 SQUID Mi10803 Channel 1 Gain X100 Slew Normal Heat Time 1k R 2 sec Cool Time 99 sec Triangle Amplitude 1 65 Vp p Bias 35 Bias 35 Mod 12 Skew 18 Table 3 2 SQUID perf...

Page 24: ...SMM 770 Scanning Magnetic Microscope System TRISTAN TECHNOLOGIES Page 24 Figure 3 4 SQUID noise spectrum at 0 200Hz 81 8 Kelvin gain x100 Figure 3 5 SQUID noise spectrum at 0 3 2 kHz 81 8 Kelvin gain...

Page 25: ...s Table 3 3 Calibration Parameters for SMM 770 Close Wire Spacing Wide Wire Spacing SQUID to Wire Lift off 0 003 76 m 0 009 229 m 0 0016 400 m 3 4 1 Lift off SQUID to Source spacing Determination SQUI...

Page 26: ...ce This result is verified by successive horizontal scans at increasing liftoffs and a pair of vertical scans of two sets of parallel wires The vertical scan plots illustrate the position of the SQUID...

Page 27: ...8 mm 0 9 mm Scan Data Theoretical Window SQUID Figure 3 10 Vertical scan of parallel wires 0 003 apart 3 4 2 Spatial resolution Resolution is defined as the smallest detectable change in position of...

Page 28: ...two central data points Therefore the system spatial resolution is better than 50 microns 76 micron wire separation meander peak 6 00E 06 T 6 20E 06 T 6 40E 06 T 6 60E 06 T 6 80E 06 T 7 00E 06 T 7 20E...

Page 29: ...The first plot is the entire subject a US Dollar bill The outputs are at resolution of 10 micron step size of the middle three letters in the word STATES on the front above the bust of Washington Figu...

Page 30: ...Model SMM 770 Scanning Magnetic Microscope System TRISTAN TECHNOLOGIES Page 30 Figure 3 14 The following output of data is a 3D post processing of the image shown in Figure 3 13...

Page 31: ...stan recommends caution when doing so Tristan strongly recommends that the user do not edit the Default ini file but rather make copies of it and edit those All ini files are presented in the dialog b...

Page 32: ...Figure 4 2 Main panel after system start In the upper right corner a text box shows system messages These messages are automatically logged to a text file under c MagScan System_Log YYYYMMM date _ tim...

Page 33: ...this SMM 770 delivery Assorted controls related to excitation such as phase shift and its real and imaginary components are disabled throughout the user interface 4 3 TRACK CONSTRUCTION The Track tab...

Page 34: ...ontinuous track can be displayed by pressing the button on the right from SloScan to QuikScan Because of the nature of the hardware the full set of coordinates over which to continuously move the stag...

Page 35: ...oscope System TRISTAN TECHNOLOGIES Page 35 Figure 4 5 Preview of QuikScan continuous track 4 4 MOVE MANUALLY The Move tab manually controls the stage This is useful for moving the stage to a position...

Page 36: ...t The HOME button will force the stage to home this is theoretically unnecessary but this utility is provided in the event of a hardware error 4 5 SQUID PARAMETERS The SQUID tab controls the iMAG sett...

Page 37: ...ations during an auto tune procedure 4 6 ACQUISITION PARAMETERS The Acquire tab controls the data acquisition parameters The Sample Rate can be adjusted from 10 Hz to 10 kHz The Settle Time defines th...

Page 38: ...age 38 Figure 4 8 Data acquisition parameters 4 7 FILTER PARAMETERS The Filter tab controls the software filtering of raw SQUID data This is not to be confused with the hardware filtering of raw SQUID...

Page 39: ...Filter parameters In general these filter settings are only useful for minimizing the Mains noise seen under the Raw Data tab They will not have much affect on the calculation of DC and AC components...

Page 40: ...10 Scan controls The Start Scan button will initiate discrete scanning using the track defined under the Track tab This scanning can be stopped by pressing the button again The progress of the scanni...

Page 41: ...rack count reaches zero Data at each track point is averaged If the track count is set to 1 the track is repeated endlessly Pressing the QuikScan button will perform a continuous scan of the sample ap...

Page 42: ...e palette controls The 3D graph can be rotated by control rightclick and dragging the mouse across the graph panned by shift rightclick and zoomed by alt rightclick The current location of the scan st...

Page 43: ...Model SMM 770 Scanning Magnetic Microscope System TRISTAN TECHNOLOGIES Page 43 Figure 4 13 Contour lines in the 3D plot...

Page 44: ...Model SMM 770 Scanning Magnetic Microscope System TRISTAN TECHNOLOGIES Page 44 Figure 4 14 Cursor usage in the 3D plot...

Page 45: ...n the 3D plot The X and Y values from the cursor can be exported to the track parameters under the Track tab by pressing the small round button next to the track parameters table This is useful for se...

Page 46: ...can be plotted by using the Sample vs Ref selection under the Surface tab However to do this the user must have data loaded as Sample and data loaded as Reference using the utilities provided under th...

Page 47: ...agScan Experiment_Data YYYYMMM date _ time _MagScan txt If the sample was scanned using the discrete SloScan the file extension will be txt if the sample was scanned using the continuous QuikScan the...

Page 48: ...40 000 0 000 1 10870E 7 0 00000E 0 10 000 40 000 0 000 1 11470E 7 0 00000E 0 0 000 40 000 0 000 1 14418E 7 0 00000E 0 10 000 40 000 0 000 1 16637E 7 0 00000E 0 20 000 40 000 0 000 1 16594E 7 0 00000E...

Page 49: ...Model SMM 770 Scanning Magnetic Microscope System TRISTAN TECHNOLOGIES Page 49 Figure 4 19 Deletion of data files...

Page 50: ...ion It is started by clicking on the Camera icon on the desktop This will open up a front panel on the right hand monitor that shows the live camera image The image can be panned and zoomed using the...

Page 51: ...the Dewar Use a throttle valve or a short pulsing motion on the Cryolab plug valve to keep the flow rate low especially in the beginning when the bulk of the air is being removed 5 2 2 Liquid nitrogen...

Page 52: ...When the Dewar has emptied itself and the danger of liquid nitrogen burns has passed the window must be sealed and the Dewar evacuated as soon as possible 2 To reduce the chance that the SQUID sensor...

Page 53: ...ology for service Keep alcohol and solvents off the Sensor window edges at ALL times IT WILL DISSOLVE the adhesive causing loss of vacuum 5 3 Gantry Maintenance Oil and grease the x y stages per Parke...

Page 54: ...t table with the Activator installed in a horizontal configuration Figure 6 2 Passive Newport table vs Newport table with activator and without activators and load of 500lbs 6 3 Option 77T Tilt Tip Fr...

Page 55: ...tilt Y tilt Full 360 deg turn of knob across 150 mm of stage surface yields back 17 mil front 5 mil which is 0 1165 deg of tilt A 1 deg turn of the tilt adjustment thus causes 150 mm tan 0 1165deg 36...

Page 56: ...st ring option 77B The field profile for the ring for an unshielded laboratory measurement utilizing a Hall probe is shown in Figure 6 4 and Figure 6 5 Field along Z axis 3 2 1 0 1 2 3 4 5 6 55 45 35...

Page 57: ...32 22 12 2 8 18 28 Distance mm Field G Field along X axis 0 10 20 30 40 50 32 22 12 2 8 18 28 Distance mm Field G Figure 6 5 Field profile along y and x axis of magnetic ring The system ran well with...

Page 58: ...Model SMM 770 Scanning Magnetic Microscope System TRISTAN TECHNOLOGIES Page 58 Figure 6 6 Noise spectra of SMM 770 system with 5 5 Gauss external applied field Gain x100...

Page 59: ...ciated digital micrometer provides up to 1 inch travel length with a 1 m repeatability A laser ranger and associate display allows for a relative position reading within a 10 m accuracy The factory se...

Page 60: ...ylinder should be avoided as much as much as possible to reduce risk of damage The door should be opened and closed slowly to avoid bending the hinges of damaging the twist lock fasteners One note abo...

Page 61: ...ing 16 from base inside dims hinges on right side at 4 00 o clock door is not centered This is the primary access for sample set up and change and has easy finger operation closing fasteners 2 top por...

Page 62: ...Liquid Nitrogen Sensor Installed Location 10 V A 293 883 77 46 0 005 19 79 0 005 Pt100 385 Wire Bundle base 10 V B 293 874 77 51 0 03 19 81 0 02 Pt100 385 Probe Tip 33 V A 77 406 0 001 19 773 0 002 Pt...

Page 63: ...Scanning Magnetic Microscope System TRISTAN TECHNOLOGIES Page 63 7 2 Calculating B fields This section is for assistance in calculating various magnetic fields for different geometries Units are cgs...

Page 64: ...Model SMM 770 Scanning Magnetic Microscope System TRISTAN TECHNOLOGIES Page 64 7 2 2 Field at center of loop 7 2 3 Field above straight wire...

Page 65: ...Meander Field Field in nT is given by 10 2 2 2 2 2 4 2 2 2 I x x d x h d x d x h d x Bm Where d Separation between wires 0 00762 cm x horizontal distance with respect to meander center cm h Vertical l...

Page 66: ...xis 1 X Axis left right Axis 2 Y axis forward back LIMIT SWITCHES Limit switch yellow wire CCW limit NO Pin 1 of Limits terminal block of MID 7602 Limit switch green wire home NO Pin 2 of Limits termi...

Page 67: ...elocity_ RPM 240 0 Stage motor velocity same for all three axes MotorAccel_ RPS s 20 0 Stage motor acceleration same for all three axes HomePosition_ mm 0 0 75 Offset of stage home position for the X...

Page 68: ...ation AO_Port Dev1 ao0 Specifies port to be used for output of an excitation signal The available ports are listed under NI MAX Channel 1 Specifies the channel number to assign to the excitation chann...

Page 69: ...ev1 ai0 9 NumChans 1 Specifies the number of channels specified under AI_Port For example if AI_Port Dev1 ai0 9 then NumChans 10 NumSQUIDs 1 Specifies the number of SQUID channels This number must be...

Page 70: ...AC amplitude and AC phase relative the the excitation sensing Settle_Time_ s 0 100 Duration to wait after a discrete SloScan stage movement and before acquisition of a block of data for analysis Samp...

Page 71: ...ult software filter IIR order Allowed range is 0 to 3 FIR_Taps 10 Default software filter FIR taps Allowed range is 0 to 100 Zero_Phase FALSE Default software filter zero phase enable disable Either T...

Page 72: ...ult Z axis trim enable disable Either TRUE or FALSE Illumination_Active FALSE Default 3D display illumination enable disble Eithe TRUE or FALSE Illumination_Color 16777215 Default 3D display illuminat...

Page 73: ...4 Background subtraction The following two figures show the capability of scan subtraction The first Figure shows a background scan in an unshielded environment The second Figure shows the result of...

Page 74: ...y 05 CGA Y axis Minimum travel distance 77 mm 13 May 05 CGA Maximum travel distance 77 mm 13 May 05 CGA Backlash 8 microns 27 May 05 CGA Movement resolution 10 micron 27 May 05 CGA Nominal 500 micron...

Page 75: ...SQUID room temperature connections when the SQUID is cold or disconnect the powered FLL amplifier at the dewar connector DO remove the fiber optic power cable from the FLL first and then the cryo cabl...

Page 76: ...in conjunction with a closed container This is especially important in humid or damp environments Typically desiccant Silica Gel appears blue when active and red or pink when saturated with moisture W...

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