Plasma processing device and method of uniform etching substrate

Abstract

The invention discloses a plasma processing device and method of a uniform etching substrate. The plasma processing device comprises a plasma processing cavity, wherein a base is arranged in the plasma processing cavity and is used for supporting the substrate, a focusing ring encircles the substrate, at least two automatic bias voltages which can be superimposed are generated on a surface of the focusing ring by applying a radio frequency signal, and when the thickness of the focusing ring is corroded and thinned with plasma bombarding, the phase of a certain automatic bias voltage is adjusted so that phase difference exists between the two automatic bias voltages. and therefore the sum of the automatic bias voltages after being superimposed is changed, and the regulation of plasma distribution of an edge region of the substrate is achieved.

Description

technical field [0001] The invention relates to the technical field of semiconductor processing, in particular to a technical field capable of uniformly adjusting plasma distribution in the edge region of a substrate. Background technique [0002] In a plasma processing device, in order to ensure uniform distribution of electric field lines in the center and edge regions of the substrate, it is usually necessary to set a focus ring around the substrate, which can extend the distribution edge of the plasma above the substrate to the focus The outer edge of the ring widens the density profile of the plasma on the substrate surface. The density distribution of the plasma in the edge area on the surface of the substrate tends to be gentle, and the plasma distribution in the central area and the edge area of ​​the substrate is more uniform, thereby realizing the uniformity of substrate etching. [0003] The focus ring is a component that has a significant impact on the edge etch...

AI Technical Summary

Problems solved by technology

The existing technology uses silicon or silicon carbide as the base material to make the focus ring. With the extension of the etching process time, the surface of the focus ring will also be consumed by plasma etching.

The surface height of the focus ring decreases, the plasma sheath above it moves down, and the etching process in the edge area of ​​the substrate changes, resulting in uneven etching rates in the center area and edge area of ​​the substrate

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