Eric A. Pape

A New Etch Planarization Technology to Correct Non-Uniformity Post Chemical Mechanical Polishing

The introduction of 3-D structures and new materials for advanced logic devices at extremely fine feature size presents challenges for within-wafer and wafer-to-wafer thickness uniformity control that is critical for yield and performance. For conventional chemical mechanical polishing technology, the typical thin film uniformity across the whole wafer may not meet the desired variation target of 2-3 nm 3σ at some critical levels. Furthermore, wafer-to-wafer uniformity variation requires a wafer by wafer approach to uniformity correction. In this paper, a novel etch planarization technology is presented that combines a conventional production-proven etch process that is temperature sensitive with an inductively coupled plasma reactor equipped with a novel electrostatic chuck that provides die level thermal control. Improved process control enables cost effective uniformity improvements in excess of 85%.

Etch planarization - A new approach to correct non-uniformity post chemical mechanical polishing

The introduction of 3D devices and new materials at sub 28 nm nodes presents challenges for within-wafer and wafer-to-wafer CMP thickness uniformity control that are critical for device yield and performance. Upon CMP the typical thin film uniformity across the whole wafer is unable to meet the target of less than 2 nm 3σ variation. Furthermore, wafer-to-wafer uniformity variation requires a wafer by wafer approach to uniformity correction. In this work, a novel etch planarization approach is presented that combines a conventional production-proven etch process that is temperature sensitive on an inductively coupled plasma reactor with die level thermal controlled electrostatic chuck (ESC). Improved process control enables cost effective uniformity improvements in excess of 85%. In addition, the approach provides wafer-to-wafer tuning capabilities.