An In Situ End-Point Detection System Using Motor Power Signal for Chemical Mechanical Planarization Process

Accurate determination of a chemical mechanical planarization (CMP) process reaching the end point is an important problem in the CMP process. In present work, the variation of the motor power signal of the polishing platen in the CMP process has been investigated, and the moving average method with 121-points moving window was used to smooth the original signal curve. Experiment results showed that the processed signal could facilitate the extraction of end-point feature for the in-situ end-point detection (EPD) system and it was relatively steady before and after the layer transition stage, which made it more reliable to detect the end point in situ. Comparing with other EPD methods, the system was less complicated, and it was easier to code for algorithm development. Finally, further analysis was performed and series of experiments provided a planarized via-revealed surface with low via dishing.

[1]  Xinchun Lu,et al.  A reliable control system for measurement on film thickness in copper chemical mechanical planarization system. , 2013, The Review of scientific instruments.

[2]  Oliver Huang,et al.  Application of Real-Time Cu Thickness Profile Control in Cu CMP , 2012 .

[3]  T. Fujita,et al.  Development of Original End Point Detection System Utilizing Eddy Current Variation Due to Skin Effect in Chemical Mechanical Polishing , 2011 .

[4]  Tadahiro Ohmi,et al.  End-Point Detection of Ta/TaN Chemical Mechanical Planarization via Forces Analysis , 2010 .

[5]  H. Hocheng,et al.  In Situ Endpoint Detection by Acoustic Emissions in Chemical–Mechanical Polishing of Metal Overlay , 2007, IEEE Transactions on Semiconductor Manufacturing.

[6]  A. Sikder,et al.  Online end point detection in CMP using SPRT of wavelet decomposed sensor data , 2005, IEEE Transactions on Semiconductor Manufacturing.

[7]  Arun K. Sikder,et al.  Chemical mechanical planarization for microelectronics applications , 2004 .

[8]  Hong Hocheng,et al.  In situ endpoint detection by pad temperature in chemical-mechanical polishing of copper overlay , 2004 .

[9]  Woo-Sun Lee,et al.  Motor-Current-Based Real-Time End Point Detection of Shallow-Trench-Isolation Chemical Mechanical Polishing Process Using High-Selectivity Slurry , 2003 .

[10]  Shen-Zhang Hong,et al.  Technological study of the hydraulic extrusion–bulge forming of a three-way tube , 2003 .

[11]  Yong-Jin Seo,et al.  Signal analysis of the end point detection method based on motor current , 2003 .

[12]  Stephen Shaw,et al.  Improved metal CMP endpoint control by monitoring carrier speed controller output or pad temperature , 1999, Advanced Lithography.

[13]  K. Drescher,et al.  Endpoint detection method for CMP of copper , 1999 .

[14]  M. Krishnan,et al.  Chemical mechanical planarization: slurry chemistry, materials, and mechanisms. , 2010, Chemical reviews.

[15]  Hong Hocheng,et al.  In situ endpoint detection by pad temperature in chemical-mechanical polishing of copper overlay , 2004, IEEE Transactions on Semiconductor Manufacturing.

[16]  H. Hocheng,et al.  A comprehensive review of endpoint detection in chemical mechanical planarisation for deep-submicron integrated circuits manufacturing , 2003 .