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2D Holographic Array Standards

Precision, holographic pattern providing accurate calibration in the horizontal plane for very high resolution, nanometer-scale measurements with 144nm and 300nm pitch.

 
Model 2D/144nm Pitch   Model 2D/144nm Pitch

144nm Very High Resolution 2D Calibration Standard for AFM, STM, Auger, FIB, and SEM

Period: 144nm pitch, two-dimensional array. Accurate to ±1nm.
Refer to calibration certificate for actual pitch.
Surface: Aluminum bumps on Silicon, 4x3mm die.
Bump height (about 90nm) and width (about 75nm) are not calibrated.
Usability: The calibrated pattern covers the entire chip.
There is sufficient usable area to make tens of thousands of measurements without reusing any areas altered or contaminated by previous scans.
AFM: Use in contact, intermittent contact (TappingMode™ ) and other modes with image sizes from 250nm to 10µm.
Available unmounted or mounted on 12mm steel disks.
SEM: This specimen works well at all accelerating voltages.
Normally supplied unmounted. Can be mounted on a stub of your choice of SEM Mount Selection A-R.
Model 2D: This Calibration Reference specimen comes with a non-traceable, manufacturer’s certificate.
This states the average period, based on batch measurements. See Sample Certificate
Model 2DUTC: This Traceable, Certified Standard is a select grade. Each standard is individually measured in comparison with a similar specimen calibrated at PTB. (PTB, Physikalisch-Technischen Bundesanstalt, is the German counterpart of NIST.)
The uncertainty of single pitch values is typically ±1.4nm (95% confidence interval). Multi-pitch measurements provide the usual square-root of N improvement in precision.

Model 2DUTC Sample Certificate

Easy to use

The 2D holographic Array with 144nm is recommended because of the unique characteristics that make it especially easy to use.
The pattern is durable and allows for scanning in contact mode, which means that calibration and measurements are faster.
This is the only high resolution 2D calibration standard we know of that has all of the following characteristics that are needed for ease of use:

  • 2-dimensional array for simultaneous calibration of X and Y axes
  • pitch << 500nm
  • array of bumps means the image contrast is high even when the probe tip is slightly dull high contrast in contact mode scans pattern
  • covers the entire die, no need to hunt for the scan area.
SEM Image   Tapping Mode 3µm AFM scan   Contact Mode 5µm AFM scan

The above image (inset) was captured with a magnification setting of 100 kX and accelerating voltage 10 kV. Outside Image 20 kV.

At 5 kX, the individual bumps were still well-resolved. Large fields of view show how few defects are present. The most common defects are single missing bumps or a single extra bump inserted between lattice positions. Two vacancies are present in the image shown here.

    
During scanning in contact mode using a 0.5 N/m SiN cantilever, we did not notice any surface or tip wear affecting the image.

 

Click images for dimensions