
The precise determination of wafer geometry is essential for many processes and applications. Whether in chemical-mechanical polishing or wet chemical structuring, accurate and meaningful measurements increase process stability and also serve quality assurance purposes. Depending on the application and processing step, wafer geometry is defined using various parameters:
- Wafer/substrate thickness, thickness variation (TTV), bow, warp
- Roughness according to DIN ISO standards
- Flatness, coplanarity
- Membrane thicknesses
- Layer and layer stack thicknesses
There are two main methods for assessing these parameters: optical and tactile. The choice of method depends on the sample type and the parameters to be measured, and is made in consultation with the client.