VLS-80
The VLS-80 is a new high vacuum scanning probe microscope developed by NanoScan in Switzerland.
The VLS-80 combines uniquely high vacuum SPM performance with high precision sample navigation.
The new SPM scanner provides a scan range of 80 x 80 µm2 with 20 bit scanner resolution and allows for SPM analysis down from the nanometer up to the millimeter range.
High resolution photo navigation in combination with the new high precision sample stage provides unique possibilities for sample navigation.
The instrument can be operated under normal atmosphere condition or in high vacuum for maximum sensitivity in all dynamic SPM modes.
The NanoScan controller system supports all standard SPM modes and also supports unique features such as tip protection and long-distance surface profiling.
VLS-80 Key Specifications
1. Closed-loop metrology scanner ranging X&Y: 80 microns, Z: 10 microns
2. 20-bit digital control of the scanner stage exhibiting sub-nm bit resolution
3. High precision sample stage with 100 x 100 x 15 mm3 travel range
4. Real-time sample observation for fast and easy manual sample positioning
5. 4-quadrant beam deflection detection system compatible with all commercial cantilevers
6. Comprehensive controller and software solution with up to 2 independent PLLs
7. Perpendicular and in-plane field option, for variable magnetic fields up to
± 550 mT perpendicular and ± 200 mT in-plane to the sample surface
8. Triple-level passive vibration system
Featured Operation Modes of the VLS-80
1. Contact mode
2. Non- contact mode
3. Double pass mode
4. Lateral force mode
5. Tapping mode
6. Phase imaging mode
7. Magnetic force mode
8. Electrostatic force mode
9. Kelvin probe mode
10. Amplitude and phase modulation
11. Force-distance mode & General scan
12. Multi- frequency mode
13. Surface profiler mode
Dual-PLL Magnetic Force Microscopy
High-resolution MFM requires high-aspect-ratio tips with a thin magnetic coating. These tips can easily be damaged if they get in contact with the surface during the measurement.
On flat surfaces it is straight forward to control the tip-sample distance. However, many real-world samples are not entirely flat. The Dual-PLL MFM mode uses two fully independent phase lock loops (PLL) to control the tip-sample distance and measure local magnetic fields simultaneously. Precisely controlling the tip-sample distance prevents damaging of the tip.
1. Non contact tip-sample distance control
2. High vacuum for improved Q-factor and sensitivity
3. Dual-PLL for multi frequency cantilever excitation
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Dual-PLL MFM image of bit patterned media. Image size is 2x2µm2 |
Dual-PLL AFM image of bit
patterned media taken
simultaneously with the
MFM image. |
| The example shows the analysis of a bit-patterned media sample. Out-of-plane magnetic domains and topographic features can nicely be resolved. |
Due to the Dual-PLL MFM mode, the topographic and magnetic information can be acquired in one scan simultaneously. |
In Situ Switching of the Tip Magnetisation
The NanoScan VLS-80 microscope can be equipped with permanent magnets which allow for in-situ switching of the tip magnetisation.
This is done without influencing the sample. The switching of the tip magnetisation is software-controlled and takes just seconds.
The tip returns to the imaging area automatically with an accuracy better than 1 µm.
The images show MFM data of bit-patterned media with a pitch of 200 nm. The two images show the magnetisation of the islands before and after switching the tip magnetisation. The contrast of all islands is inverted, proving that the signal is magnetic and topographic contributions can be ruled out.
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Tip magnetised up |
Tip magnetised down |
The Perfect Companion for the TOF.SIMS 5
SPM provides valuable information about the topography and other physical properties of surfaces. Especially the correlation of physical SPM data with chemical TOF-SIMS information can provide a deeper understanding of the analysed materials.
Finding the area of interest in SPM instruments can often be challenging an time consuming. The VLS-80 uses the same sample handling system and navigation software as the TOF.SIMS 5. Thus, making sample navigation in both system fully compatible. Finding and analysing TOF-SIMS acquisition areas or sputter craters is accomplished in a matter of minutes. This allows the correlation of TOF-SIMS and SPM information in a very precise and convenient manner.
1. Image of a TOF.SIMS 5 sample holder with samples, as displayed in the SurfaceLab Navigator software.
2. Optical zoom on a sample, showing TOF-SIMS acquisition areas.
3. Top-view image showing a sputter crater measured along the dotted line using the surface profiler mode below.
The Surface Profiler Mode
The VLS-80 allows for detailed analysis of large TOF-SIMS sputter craters. In the so-called surface profiler mode multiple SPM scans are stitched together to measure long SPM line scans. This unique SPM mode is extremely valuable to precisely determine the depth of sputter craters or to measure crater roughness on the nanometre scale.
The example shows a SPM surface profiler scan of a 1.2 µm deep sputter crater in silicon. The line scan consists of multiple individual SPM scans. The recording time for the entire scan was less than 3 minutes and revealed a surface roughness of 15.7 nm (RMS) inside the crater.
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Surface profile of the sputter crater shown in image 3 (The perfect companion for the TOF.SIMS 5) |
Contact AFM image measured at position A in the surface profile |
The VLS-80