Wafer Type Ion Energy Monitoring Sensor for Plasma Diagnosis

Abstract

We propose a wafer-type ion energy monitoring sensor (IEMS) that can measure the spatially resolved distribution of ion energy over the 150 mm plasma chamber for the in situ monitoring of the semiconductor fabrication process. The IEMS can directly be applied to the semiconductor chip production equipment without further modification of the automated wafer handling system. Thus, it can be adopted as an in situ data acquisition platform for plasma characterization inside the process chamber. To achieve ion energy measurement on the wafer-type sensor, the injected ion flux energy from the plasma sheath was converted into the induced currents on each electrode over the wafer-type sensor, and the generated currents from the ion injection were compared along the position of electrodes. The IEMS operates without problems in the plasma environment and has the same trends as the result predicted through the equation.

Development of Wafer-Type Plasma Monitoring Sensor with Automated Robot Arm Transfer Capability for Two-Dimensional In Situ Processing Plasma Diagnosis

“…Also, it is not suitable for automated semiconductor processing because its system thickness exceeds 1.6 mm (i.e., the maximum height of the integrated circuits (ICs) utilized in the sensor exceeds 1.6 mm), which is beyond the height limit in typical semiconductor equipment during the automated robot arm transfer. Similarly, Han et al [ 18 ] implemented a wafer-type ion energy monitoring apparatus for in situ monitoring of the semiconductor process; likewise, it can only provide plasma information over a 6-inch processing chamber. Meanwhile, Kim et al [ 19 ] fabricated a wireless wafer-type plasma probing system that can be useful for a 12-inch processing chamber; however, its system thickness is still too thick (i.e., 12 mm) to be used for industrial applications, and the aluminum-based materials are not compatible for semiconductor processing.…”