Measurements of line pitch are often best measured using the side-to-side faces of the tip, which exhibits symmetry.. Because of the approximate 17° half angle of the tip, the line or sp
Trang 1Cantilever Preparation
Tip Shape of Etched Silicon Probes continued
Measurements of line pitch are often best measured using the side-to-side faces of the tip, which exhibits symmetry Because of the approximate 17° half angle of the tip, the line or space measurement is best done at the top of the line for simplification of the measurement artifacts (See Figure 6.2e)
Figure 6.2e Common Silicon Probe Profile (Resultant Scan Artifact)
Figure 6.2e depicts the resultant effect of the angled back ridge on the step angle measurement for a deeper trench depth This is tip and topography dependent
In addition to microscopic scale shape characteristics (See Figure 6.2b
-Figure 6.2e), another factor which can affect the wall angle over shorter (nominal 100 nm) step height measurements is the shaped cusp at the end of the tip The shaped cusp at the end of the tip is formed to increase the sharpness of the tip point to a length of 100 nm from the end of the tip It is formed in such a manner that the radius of curvature of a silicon tip can be in the range of 5–10 nm (on a very good tip)
Scan Line Profile
10°
1 µm - 2 µm Deep Trench
Note: Any wall angle on the left wall that is > 55 deg.
will be shown as 55 deg in the image.
Any wall angle on the right wall that is >70-80 deg.
will be shown as 70 -> 80 deg in the image.
Subsequent scan line produced
using the realistic tip shape
Trang 2Cantilever Preparation
Tip Shape of Etched Silicon Probes continued
Measurements of line pitch are often best measured using the side-to-side faces of the tip, which exhibits symmetry Because of the approximate 17° half angle of the tip, the line or space measurement is best done at the top of the line for simplification of the measurement artifacts (See Figure 6.2e)
Figure 6.2e Common Silicon Probe Profile (Resultant Scan Artifact)
Figure 6.2e depicts the resultant effect of the angled back ridge on the step angle measurement for a deeper trench depth This is tip and topography dependent
In addition to microscopic scale shape characteristics (See Figure 6.2b
-Figure 6.2e), another factor which can affect the wall angle over shorter (nominal 100 nm) step height measurements is the shaped cusp at the end of the tip The shaped cusp at the end of the tip is formed to increase the sharpness of the tip point to a length of 100 nm from the end of the tip It is formed in such a manner that the radius of curvature of a silicon tip can be in the range of 5–10 nm (on a very good tip)
Scan Line Profile
10°
1 µm - 2 µm Deep Trench
Note: Any wall angle on the left wall that is > 55 deg.
will be shown as 55 deg in the image.
Any wall angle on the right wall that is >70-80 deg.
will be shown as 70 -> 80 deg in the image.
Subsequent scan line produced
using the realistic tip shape