Measuring Wafer Curvature, Bow and Tilt

Wafers are very thin slices of semiconductor material used in the production of integrated circuits and photovoltaic cells. They are made through the deposition of silicon crystals. During production, various parameters such as wafer bow, curvature and stress need to be monitored in real time.

k-Space Associates supplies several in situ and ex situ tools for measuring wafer curvature, bow, and tilt. For example, the kSA MOS UltraScan is an ex situ tool for measuring thin-film stress and strain as well as wafer curvature, bow, and tilt that are induced by thin films or thermal processes on a wafer.

The kSA MOS Ultra-Scan uses a two-dimensional laser array to measure these parameters. It also uses software with high-quality 2D and 3D graphics for data display. With the increasing demand for LED and solar cells, such in-line production monitoring tools are crucial for producing quality wafers in extremely high volumes.