Silicon Wafer Processing

This chapter reviews the Si wafer-processing technology, including ingot heat treatment, cutting, slicing, lapping, polishing, wafer cleaning, and packaging. The ingot heat treatment is used to eliminate thermal donors or repair neutron irradiation damage. After the crystal orientation of Si ingot is measured by X-ray diffraction method, the wafer-making processes start. Nowadays, the blade cutting is gradually replaced by the more efficient wire sawing technology. Then, the lapping is used to remove the damage layer caused by slicing process. The most important step is the wafer polishing, for achieving “mirror like” surface with excellent geometric accuracy for device fabrication. Wafer cleaning is needed to eliminate the contamination during the former processes, followed by the wafer packaging.