AVS 51st International Symposium
    Plasma Science and Technology Tuesday Sessions
       Session PS2-TuM

Paper PS2-TuM9
Process Diagnostics and Optimization in Plasma Etch Chambers Using In-Situ Temperature Metrology

Tuesday, November 16, 2004, 11:00 am, Room 213B

Session: New Gate Conductor Etching
Presenter: P. MacDonald, OnWafer Technologies, Inc.
Authors: P. MacDonald, OnWafer Technologies, Inc.
B. Hatcher, Applied Materials, Inc.
J.P. Holland, Applied Materials, Inc.
M. Welch, OnWafer Technologies, Inc.
M. Kruger, OnWafer Technologies, Inc.
Correspondent: Click to Email
Performance metrics in plasma etching are strongly affected by various interacting mechanisms including direct chemical reaction, reactive etching, deposition, and mask erosion. Some of these basic etch mechanisms are extremely sensitive to temperature. As a result, across-wafer temperature variations are a first order indicator of etching performance in advanced plasma etch reactors. This temperature variation is a combination of effects ranging from reactor design to individual recipe parameters. With wafer-level thermal data available, any of these factors can be modified to improve process performance. This paper establishes concrete methodologies for in-situ process optimization using a wireless sensor system. The sensor system provides the precision necessary to break the ITRS "brick-wall" of "measurement precision of wafer surface temperature,"@super1@ by combining in-situ plasma SensorWafers and an advanced diagnostic data processing suite. This paper offers multiple examples on advanced polysilicon processes that illustrate rapid, effective process optimization and ESC diagnostics. In the process optimization section, state-of-the-art polysilicon etch chambers are evaluated for critical process characteristics. The effectiveness of temporal/spatial temperature signatures as indicators of process performance is demonstrated. Wafer-level thermal data is correlated to actual device results to verify performance of the optimized process. In the ESC characterization segment, multiple leading-edge ESC designs are evaluated to ensure process transferability and performance. The effectiveness of temporal/spatial temperature signatures to quickly and easily evaluate ESC design iterations is demonstrated. These diagnostics save considerable time and effort over the current methods established for ESC fingerprinting. @FootnoteText@ @footnote 1@ ITRS: 2003, Table 6, Key Sensor Technology Requirements.