Nondestructive defect characterization of saw-damage-etched multicrystalline silicon wafers using scanning electron acoustic microscopy

Defects in multicrystalline silicon wafers after saw-damage etch (SDE) for different etch durations are characterized nondestructively using scanning electron acoustic microcopy (SEAM). SEAM is shown to be able to detect both surface and subsurface defects, as well as crystallographic imperfections such as grain boundaries in mc-Si wafers. The capabilities of the SEAM imaging are further extended for investigations of the structural properties of the saw-damage-induced defects and optimization of the SDE process. It is established that SEAM could be effective in determining the optimal SDE etch duration required for the minimization or complete removal of the saw-damage layer. In addition, it also confirms that the SDE process itself does not create new line-like defects.