The Inspection Solutions and Reduction of Extreme Tiny Poly Residue

As design rule shrinks, it is essential that the capability to detect smaller defects should be improved. In this paper, extreme tiny poly-residue defects are found after poly-etch process. In order to improve the signal to noise rate, poly-residue is detected and monitored by using KLA 29XX BBP inspection system post poly-etch process. Finally, the recipe is optimized by using NanoPoint to remove the noise of poly grain. The purpose of these studies is to capture defects more efficiently and also provides a new way to reduce noise. After defect detecting failure models of these defects were established and the effective defect reduction actions were carried out.