Lower electrode device and related plasma system

Abstract

A lower electrode device applied to a plasma system. The plasma system has a lower electrode, a ring electrode disposed around the lower electrode, and a radio frequency source coupled to the lower electrode. The lower electrode device includes an electric field supply circuit, one end of the electric field supply circuit is coupled to the ring electrode, and the other end of the electric field supply circuit is selectively coupled to the radio frequency source or the ground terminal, when After the plasma is ignited, the electric field supply circuit is used to selectively couple the ring electrode to the ground terminal or the radio frequency source to adjust the electric field distribution above the edge of the workpiece, and then adjust The curvature of the plasma sheath at the edge of the work piece (such as a wafer) finally effectively solves the problem of the inclination of the process result at the edge of the work piece.

Description

technical field [0001] The present invention relates to a device, in detail, to a lower electrode device and a related plasma system. Background technique [0002] When a workpiece (eg, a wafer) is being processed by a plasma process, the process performance of the workpiece (eg, a wafer) depends primarily on the plasma composition over a specific area of ​​the chip. Due to electrical inhomogeneities over finite dimensions, the electric field distribution over the edge of the workpiece (e.g. wafer) is different from that over the center of the workpiece (e.g. wafer), resulting in the bending of the plasma sheath at the edge of the workpiece , which in turn makes the process result at the edge of the workpiece (such as a wafer) tilted. As a result of the inclined process, the performance of the workpiece (eg, wafer) may not be as expected in the design, which may seriously cause the edge area of ​​the workpiece (eg, wafer) to become unusable, increasing the manufacturing cos...

AI Technical Summary

Problems solved by technology

Due to the electrical inhomogeneity caused by the finite size, the electric field distribution above the edge of the workpiece (such as a wafer) is different from the electric field distribution above the center of the workpiece (such as a wafer), resulting in bending of the plasma sheath on the edge of the workpiece , which in turn makes the process result at the edge of the workpiece (such as a wafer) tilt

As a result of the inclined process, the performance of the workpiece (such as a wafer) will not be as good as it was designed, and it will seriously cause the edge area of ​​the workpiece (such as a wafer) to become unusable, increasing the manufacturing cost of the device.

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