X-ray diffraction imaging (XRDI, also known as X-ray topography) is used to image crystalline defects in otherwise perfect (or near perfect) substrates. In SiC monitoring it detects crystalline defects through the wafer body. The Sensus-CS has been developed to be able to measure SiC substrates at ~5µm resolution at production compatible throughputs and provide automated defect maps of common defect types, including Threading screw dislocation (TSD), Threading edge dislocation (TED), Basal plane dislocation (BPD) and micro-pipes (MP). The analysis was developed even for cases where defects overlap in wafers with relatively high defect density.
The fully automated nature of the Sensus-CS tool allows the densities for each defect type can be extracted and automatically reported via SECS/GEM for instantaneous feedback to production.
For large grains and single crystals, micro-XRF technique allows a quick mapping of crystalites by visualizing the appearance and disappearance of Bragg peak in the according spectral ranges. Such Laue map reveals the different crystallites domains. In sufficiently large single crystals, certain types of defects and orientation changes can be visualized.