Figure 7
From: Lens-free reflective topography for high-resolution wafer inspection
High-resolution topography for measuring the scratch depth. (a) Scratch model on the wafer surface. This is a model of the scratch defect generated during the wafer manufacturing process, particularly the chemical-mechanical polishing (CMP). (b) Reconstructed amplitude image of the position pointed by the arrow in (a). (c) High-resolution topography of the scratched area indicated by the red box in (b). (d) Line plot graph of scratch depths corresponding to each position in (c). The red and blue lines are with and without the diffuser, respectively. The black line is the reference value of the scratch depth. (e) Graph of scratch depth quantification with position. A comparison of reference values reveals that the presence of speckle illumination improved the accuracy of scratch depth measurement from 69.3 to 98.1% compared to its absence.
