Specific Process Knowledge/Characterization/Sample imaging
Sample imaging
A Danchip a number of instruments are available for sample imaging, including a several optical microscopes, an optical profiler, three SEMs (scanning electron micrscopes), an AFM (atomic force microscope) and two stylus profilers (Dektak). These instruments cover wide range of applications.
Optical micrscope... The optical microscopes provide fast and easy information about most samples without any sample preparation. But the resolution is limited by the objectives and the wavelenght of the light. Also the depth of focus is limited, especially at high magnifications.
Optical profiler... The main purpose of the optical profiler is 3D imaging of sample surfaces, step height measurements, roughness measurement.
The optical profiler provides standard microscope imaging, confocal imaging, confocal profiling, PSI (Phase Shift Interferometry), VSI (Vertical Scanning Interferometry) and high resolution thin film thickness measurement on a single instrument. The main purpose is 3D topographic imaging of surfaces, step height measurements in smaller trenches/holes than can be obtained with standard stylus method, roughness measurements with larger FOV than the AFM, but less horisontal resolution.
SEM...
AFM...
The AFM is used to study samples with nanoscale structures. The field of view and is very limited, and the scan speed is slow, so it only possible to get information a small part of the sample at a time. The resolution is limited by the tip (width ~ 5 um, angle ~ 45 degrees for the standard tips), but it is possible to buy special tips for inspection of high aspect ratio structures. Futhermore, wi
Dektak... The Dektak is a slylus profiler where a stylus scans across a surface to perform very fast step height measurement. The vertical resolution is very high, but the horizontal resolution and the aspect ratio you measure are limited by tip (width ~ 5 um, angle ~ 45 degrees). Stress measurements can also be sone with the Dektak.