Decreasing device dimensions and increasing wafer diameter lead to a steady concern with respect to the impact of mechanical stresses in silicon technology. The move to 300 mm wafers without up scaling the wafer thickness leads to an increased importance of gravitational stresses which add to the thermal stresses thus leading to a revival of the warpage problem. Local isolation and silicidation are both struggling with stress problems often leading to dislocation generation or edge geometry problems. A model is discussed to predict dislocation nucleation and applied for patterned thin film structures. New developments of micro-Raman spectroscopy and transmission electron microscopy for the assessment of localised stress distributions are presented.
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