Sphere defects prevention on shallow trench isolation etch

This paper presents our study on the cause of sphere defects in shallow trench isolation etching and preventive measures put in place. Sphere defects are generated as a result of microarcing due to deterioration of ESC chuck condition. To detect sphere defects, ESC leakage current is a good gauge to determine the sign of ESC breakdown. Solution to prevent sphere defects and monitor ESC chuck lifetime was discussed in this paper.