| Advantages |
1) Excellent depth resolution of 5nm. Very good Lateral Resolution down to 1.1micron.
2) Works on high aspect ratio surfaces and angular surfaces. This allows to test all types of materials including paper, textile, sand paper.
3) Works on materials of any colors and reflectivity.
4) Quick, up to 4000points per second.
5) Wide range from nm to 24mm combine with good lateral resolution allows both metrology and surface roughness to be measured. |
1) Excellent depth resolution 0.1nm. Very good Lateral resolution down to 0.3microns
2) Use CCD camera to take roughness measurement in a few seconds.
3) Stitching technique allows to cover large surfaces
4) Ideal for many microelectronic applications
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1) Good for metrology work
2) Somewhat faster than Chromatic Aberration Techniques
3) Lower price technique compare with chromatic aberration because of its limits.
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1) Lowest price Technique for standard systems.
2) Depending on design can test steep angular surfaces. |
1) Best lateral resolutions for detail imaging
2) Can reveal surface structure in details |
| Disadvantages |
1) Higher resolution in Z direction might be needed. Phase shift technology goes down to 0.1nm.
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1) Difficulty on high angular surfaces or surface where line of interference pattern are difficult to see. Chromatic Aberration Technique works better on these surfaces.
2) More limited than White light chromatic aberration in the Z direction. Stitching allows a few mm. |
1) Because of shadow effects caused by incident light not being perpendicular to the surface, it is impossible to measure high aspect ratio surfaces.
2) Lateral resolution limited to 30microns in most systems and sometime down to 10microns. This with also a limited Z resolution makes it difficult to accurately measure roughness.
3) With standard wavelength it is impossible to measure dark blue surfaces or black surfaces. |
1) Tip size often larger than 10microns but can be down to 1microns in higher priced system.
2) Depending on size of probe and load applied, deformation may occur on softer materials such as polymers or plastics.
3) Normally 2D instruments.
4) Slow especially if 3D imaging is performed. |
1) Slow compare to white light systems
2) Requires more knowledge for use.
3 Relatively small surfaces can be tested (100microns by 100microns) |
infoca@microphotonics.com