Infineon Technologies Dresden

1. 4 polish heads Infineon Technologies Dresden Control goal R2R control of CMP PSG process by adjusted zone pressures and polish time Sebastian Wehring, Frank Reinhold, Jan Zimpel , Thomas Igel In process steps following the CMP PSG step (e.g. Litho, Etch) the Gate contacts have to be established throughout the whole wafer. This requires a control scheme which ensures a constant remaining PSG layer thickness throughout the whole wafer. Process sequence Target Control scheme This goal can be achieved by a R2R controller combining the thickness control by polish time and the uniformity control by pressure. CVD PSG Deposition equipment • Logistic information • Layer thickness • Layer distributions Feedforward 6 deposition chambers Pre layer Target R2R Control predict filter update Recommend wafer fine time & pressure settings zone pressures & time PSG polish calculated quantity • layer thickness • layer distribution • used pressures • used time Results to date Feedback Estimated benefit of about 20% in reducing RMSE DoE I - Removal on Time Dependency • Benefit Analysis • Controller Design & Parameterization Methodic • Controller Software Development • Controller Integration • Zone Classification • Removal on Time Dependency Analysis (DoE I) • Zone Pressures Interactions Analysis (DoE II) • Inline Data Collection – ongoing • Control Parameter fine tuning – ongoing Removal Polish Time DoE II - interaction between head zones  Matrix M (characterizes pressure action) Removal/Pressure Radius 8th European Advanced Equipment Control / Advanced Process Control (AEC/APC) Conference Dresden - Germany, April 18 - 20, 2007