3DP is a non-contact optical metrology technique which provides measurement of the physical characteristics of a material including :-

• Microtopography
  
• Form and texture surface analysis
  
• Roughness
  
• Dimensional metrology
  
• Layer thickness measurement.

3DP can provide quantification of surface topography and accurate measurement of dimensions.

The Technique

The 3DP technique combines white light illumination of the sample with spatial filtering in a confocal microscope system to provide measurement of the height of the sample (z-axis) as it is moved across the detection plane using an XY translation stage. The resolution of the measurements are <1µm in X and Y axes and <10nm in the z-axis. Hence microfeatures and large scale topographic variations can be monitored in detail. Sample sizes from a few mm² to 100mm x 100mm can be measured with a height variation over the sample of up to ~25mm.

Resolution

xy resolution <1micron
z-axis resolution <10nm

Data Formats

Pseudo-colour height maps of the surface where the height scale (z-axis) is colour-coded. This allows 3D graphical representation of surface topography. 3D images providing variable angle viewing and rotation of the 3D representation of the surface. Pseudo-colour map from a polymer sheet sample showing the presence of anti-block agent, appearing as intense circular features of size ~1-10µm diameter.

• Amplitude parameters - allowing classification of various aspects of topography - some typical parameters are:
  Sa - arithmetic mean of the deviations from the mean, i.e. "surface roughness" parameter;
  Sp - highest peak of the surface;
  Sv - deepest valley;
  St - total height between highest peak and deepest valley;
  Ssk – relative amount of peaks to valleys (+ve values indicate more peaks than valleys, negative values more valleys than peaks);
  Sz - mean of distance between the five highest peaks and five deepest valleys.

• Profilometry - allowing multiple line scans across any user-defined XY plane of the sample.
  

  

  Line scan across contact pads of the PCB sample as shown in the image on the right.

• Examples of 3DP profiling of Silicon Carbide



• Examples of 3DP profiling of a Cam Shaft



• Examples of 3DP profiling of an Integrated Circuit Board