Tip Shape Issues
Rev. F
Scanning Probe Microscope Training Notebook
55
The ability to image steep sidewalls on a sample surface is determined by the sidewall angles of the
tip.
The tip is not able to profile sides of surfaces steeper than the sidewall angle of the tip.
•
When scanning across features which are steeper than the sidewall angle of the tip, the
sidewall angle in the images will reflect the sidewall angle of the tip.
The following examples show the resulting angles and image profiles of silicon nitride and silicon
tips scanned over trenches with 90° sidewall angles.
The tip is mounted in the cantilever at ~10°, so the angles measured with the front and back sides of
the tip will be skewed by ~10°.
Figure 19.0c
Sidewall Angle Measurements of Trench with Vertical Sidewalls Acquired with Silicon Nitride
Probe
Figure 19.0d
Sidewall Angle Measurements of Trench with Vertical Sidewalls Acquired with Silicon Probe
Scanning Angle From Front to Back
(Scan Angle = 0°)
Scanning Angle From Side to Side
(Scan Angle = 90°)
Scanning Angle From Front to Back
(Scan Angle = 0°)
Scanning Angle From Side to Side
(Scan Angle = 90°)