AVS 47th International Symposium
    Plasma Science and Technology Wednesday Sessions
       Session PS1+MS-WeA

Paper PS1+MS-WeA4
Run-to-Run and Real Time Process Control of Plasma Processes using an Inductive Antenna with Microsecond Resolution

Wednesday, October 4, 2000, 3:00 pm, Room 310

Session: Sensors and Control in Plasma Processing
Presenter: J. Mathuni, Infineon Technologies AG, Germany
Authors: J. Mathuni, Infineon Technologies AG, Germany
F.H. Bell, Infineon Technologies AG, Germany
D. Knobloch, Infineon Technologies AG, Germany
Correspondent: Click to Email
Equipment and process stability during the fabrication process of integrated circuits is one of the main issues in current and future production lines. This is particularly mandatory for plasma processes. Intelligent run-to-run and real time control using plasma sensors help to prevent wafer scratches or misprocessing and to monitor chamber drifts, e.g. caused by damaged reactor walls or polymer coating on chamber walls during wet cleans. We have implemented the real time control of plasma processes using an in house developed antenna that measures the electric field of the plasma with microsecond resolution. Introduction of this sensor in our fabrication lines was challenged by two factors, namely, the development of robust and low cost hardware and easy to use software including process and equipment related control algorithm. The latter needs special attention, since the time resolution in the range of microseconds results in a very high amount of data making intelligent data reduction techniques mandatory. The measurement technique requires a dielectric material between plasma and sensor that can be easily realized using the quartz endpoint window of the plasma chamber. The benefit of this sensor is demonstrated for applications such as arcing detection, a phenomenon that may occur during microseconds and results in yield killing particle generation, and process parameter dependencies, such as B-field and power analysis. As a result, preventive maintenance is automatically triggered by sensor data. Since the sensor allows electric field measurements with nanosecond resolution, analysis of pulsed plasmas could be a further application.