A Study of Minimum ISO-Dense Etching CD Bias Loading Performance on Advanced Logic Trench Process

Iso-dense loading including critical dimension (CD), depth and profile etc. is becoming a challenge for both Logic front-end-of-line (FEoL) and back-end-of-line (BEoL) patterning due to the need to scale the pitch [1] - [2]. In this paper, trench process iso and dense CD performance had been evaluated for both devise and reliability uniformity window. By using AppliedPRO<sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">™</sup> [3], a systemic investigation was performed to find the tuning knobs of iso to dense etching CD bias loading. Based on DOE and tuning knob window split, our results indicate that iso to dense CD bias loading can be tuned. This study demonstrates efficient way to find the tuning knob and develop relative etching recipe.