FEI Sirion XL30 SEM Standard Operating Procedure v.0814 1 XL30 Operating Procedure Table of Contents 1. 2. 3. 4. 5. 6. 7. 8. 9. 10. 11. 12. 13. 14. Enable SEM Load Sample (2) SEM Imaging Parameters SEM Detectors Stage Map Start High Tension Calibrate Stage Height Raise Stage to +10mm Recalibrate Stage Height Lens Alignment Correct Astigmatism Acquire Micrograph Export Micrographs Acquire Extra-High Definition 15. Filters 16. Shutdown 17. Default Settings 2 Enable SEM • Use the support PC and login to the NTUF Coral Server. “Enable” the SEM. This will remove the Clear Lock password screen and allow you use the SEM. • XL Microscope Control program should be running on the right monitor. • Scandium image analysis software should be running on the left monitor. WARNING: Never touch the main power buttons on the front panel of the Sirion table. 3 Load Sample Sample Mounting: The maximum mounted-sample size is 50x50x20mm (LxWxH). Clean any organic residues from the sample with alcohol, remove lose debris with compressed air, and handle samples with tweezers and gloves to keep them clean. 1. Select “Vent” in the Vacuum menu. 2. Insert sample stub and tighten using set screw (finger tight). 3. Set the Height Marker on the stage base and check that there is at least 5mm of clearance between the sample and probe lens. 4. The stage switch should be set to “A” for imaging or EDS. 5. Watch the clearance on the CCD monitor as you close the chamber door. 6. Hold the door closed and select “Pump” in the Vacuum menu. 4 Load Sample If ‘Microscope Problem: Sample Touch Alarm’ appears while loading samples, it is generally a false alarm. 1. Check the clearance on the CCD to verify there is no contact with the roof of the chamber. 2. If it is clear that there is no contact with the sample, click “OK” and continue. 3. If there could be contact, do not attempt to move or remove your sample – get staff assistance. 5 SEM Imaging Parameters Z Position Beam tab SEM imaging should be done between +5 and +10mm of absolute clearance. Beam Accelerating Voltage 5 kV is the default and works for the widest variety of samples. Lower voltage gives better surface sensitivity to images. Higher voltages can penetrate passivation layers to reach conductive layers below. Spot Size Correlates to beam current (scale 1-7, where 1 is the smallest current). Spot 3 is the default and generally gives good signal/noise ratio. Nonconductive samples will charge less at Spot 2. Image brightness will improve with higher currents, but resolution is lower. 6 SEM Detectors Detector The default (search) mode uses an Everhart-Thornley detector to collect secondary electrons (SEs). The through-lens detector (TLD) is most effective in either UltraHigh Resolution (UHR) mode or in Backscatter mode. UHR Mode UHR mode is not safe for magnetic samples and must not be used with the EDS detector inserted • The exact magnification required will depend on your current forward working distance. • When Mag and WD conditions are met, the UHR icon (at right) will no longer be grayed-out. • Many detector options are available on the TLD. Access them through the Detector Tab -> Change. 7 Stage Map Minimize/Maximize Stage menu 1. Locate the stage reference map in the maximized “Stage” menu. 2. Double click the map to move sample(s) into position for viewing. The beam location is marked with an “x”. 3. Wait for vacuum status message to read “Vacuum OK.” 8 Start High Tension 1. Start the High Tension (HT) from “Beam” menu by clicking the ‘kV’ button. “Microscope Confirm Focus” will appear DO NOT CLOSE THIS BOX 2. Auto adjust brightness and contrast (F9). 9 Calibrate Stage Height 1. Move to the tallest part of the sample using a stage movement tool. Get Mode – left double-click Track Mode – left click and hold between rings 2. Use ‘+’ and ‘ –’ buttons on number pad to increase/decrease magnification respectively. 3. Click and hold the right mouse button then focus side-to-side on the tallest part of the sample. 4. With magnification ≥ 2000X and sample in focus click “OK.” • Working Distance (WD) will update the Stage Height (Z). 10 Raise Stage to +10mm While stage is moving up or down: cover the Cancel button in the Stage Movement window (upper left corner of the Microscope Control program.) 1. In the “Stage” menu select Z = 10 mm and click “Goto.” 2. Watch the CCD monitor and “Cancel” the stage move if the sample gets too close to the probe lens. Probe Lens 3. Refocus the sample at this new stage height with magnification ≥ 2000X. 4. Click Z<=>FWD in the “Stage” menu to reopen the Microscope Confirm Focus box. 11 Recalibrate Stage Height 1. With the sample in focus click “OK” to update the stage height. 2. Select the final Z ( 5 mm) and click “Goto,” raising your sample up to the final WD. 3. Move to the area of interest using the stage movement tool. Final Z-Height Micro-scale Features Z  7.5 mm Tilted Samples Z = 7.5 mm E-Beam Lithography = 6.5 mm Nano-scale Features Z = 5 mm X-ray Analysis Z = 5 mm 12 Lens Alignment (optional) 1. Change Scan rate to ‘TV.’ 2. Increase magnification to ≥ 10,000X. 3. From “Beam” menu activate the “Lens Modulator” by checking the box. 4. In the “Lens Align.” window, left-click and hold to start the adjustment. 5. Move left-right to correct for X image wobble or up-down to correct Y. • Final image should appear stationary under the white crosshairs. The image will only oscillate in/out of focus. 6. Uncheck Lens Modulator when done. 13 Correct Astigmatism 1. Obtain the best possible focus on image. (See examples below) • Image should not exhibit streaking or distortion before adjusting stigmation. 2. Hold down “Shift” key and right mouse button to start the adjustment. 3. Drag green cross in X & Y until image resolution is well defined. 4. Refocus image using right mouse button. Incorrect focus and astigmatism. Correct focus before stigmation adjustment. 14 Acquire Micrograph Standard Definition F2 Capture (single frame: 720 x 968 pixels ~ 300 kb) 1. Push “F2” key to grab an image and wait for the scan to finish. 2. Do not proceed until the snowflake icon turns yellow. 3. Select your folder in the Scandium database. 4. Click camera icon to transfer image to Database ‘Scandium.’ 5. Unfreeze image with ‘snowflake’ button to return to live imaging. 15 Export Micrographs to Coral 1. Highlight the thumbnails to transfer in Scandium. 2. Click to export images as TIFs. 3. Browse “My Computer” and select Coral drive (M:) or (Q:) as the destination. Browse 4. Click “OK” to transfer images. • Files will be saved for 2 weeks on the M: drive and then automatically deleted. Remember: Download all of your files from M: before the 2 week deadline. 16 Acquire Extra-High Definition Extra-High Definition F5 Capture (single frame: 968 x 1404 pixels ~ 1.2 Mb) 1. From “Image” menu in Scandium, select “Configure Input.” 2. Select “Input” tab to define Acquisition mode. Standard High Definition = F2 Extra High Definition = F5 3. In Microscope Control XL push the “F5” key to grab an image. 4. The file is saved as LAST.TIF on the C: drive. 5. Drag-and-drop to M: and rename each image as you collect it. Always reset Input to Standard/High Definition when you are done. 17 Filters If the single scan electron image looks flat or shows other signs of charging, you may be able to eliminate these artifacts by Integrating TV scans. 1. From the Filter Tab choose “Integrate XX Frames.” • The image will start black and build as frames are added. 2. Wait for the Snowflake icon to light. 3. Click camera icon to transfer image to Database ‘Scandium.’ 4. Unfreeze image with ‘snowflake’ button to return to live imaging. • You can change the number of frames integrated from the Filter Tab > Setup 18 Shutdown 1. In Beam Submenu click “kV” to close the column valve and ramp down HT. 2. In the Stage submenu type in Z=30 mm and click “Goto.” 3. Message ‘Exceeds stage range.’ Click “Yes” to move stage to lowest possible position. 4. Wait for the stage to lower completely, then select “Vent” in Vacuum menu. 5. Reset Beam to 5kV, spot 2 or 3. 6. Reset any other changes you made to default settings (next page). 7. Wait for specimen chamber to reach atmospheric pressure (approximately 2 minute). 8. Open the chamber, loosen set screw, and remove samples. 9. Close the chamber door and select “Pump” in Vacuum menu. 19 Default Settings SOFTWARE Scandium Microscope Control • Magn > Reference (Videoprint) • Beam > 5kV Spot Size 2 • Scan > Full frame • Scan Presets > Slow 1: 1.7ms, 484 lines Slow 2: 6.7ms, 484 lines Slow 3: 16.5 ms, 484 lines Slow 4: 33.2ms, 484 lines Single: 33.2ms, 968 lines XHD: 66.4ms, 1420 lines • Filter (TV) > Average 8 frames & Standard def. • Filter (Slow Scans) > Live, Standard def. • Stage >  Stage Current  Auto beam shift zero Setup > Image > Configure Input >  Standard High Def. HARDWARE • Stage Switch: “A” (Alarm) • External Beam Blanker: Off • A/B Switch Box: A (EDS) • Belkin KVM Switch: EDS • CCD Camera Toggle: On • External (CCD) Monitor: On • EDS detector: Retracted 20