Inductive coupling plasma processing system and processing method

Abstract

The present invention provides an inductive coupling plasma processing system. The inductive coupling plasma processing system comprises a radio-frequency power supply system consisting of a source radio-frequency power supply system and an offset radio-frequency power supply system; the source radio-frequency power supply system includes a radio-frequency power supply and a source matching network; and the offset radio-frequency power supply system includes an offset radio-frequency power supply and an offset matching network, wherein the source matching network is a fixed matching network with wide broadband work, and the offset matching network is an automatic matching network. The source matching network can allow the impedance of the source radio-frequency power source to rapidly match the impedance of the plasma, and the offset matching network can obtain very low reflection power at the time in the low-offset radio-frequency power. Therefore, the processing system can realize the rapid and accurate regulation of the impedance between the radio-frequency power supply and the plasma. Besides, the present invention further provides the processing method of the plasma such as inductive coupling and the like.

Description

technical field [0001] The invention relates to the field of semiconductor processing equipment, in particular to an inductively coupled plasma processing system and processing method. Background technique [0002] Inductively coupled plasma processing systems include radio frequency power systems. Wherein, the RF power system includes a source RF power system and a bias RF power system. Among them, both the source RF power system and the bias RF power system include two parts: the RF power supply and the matching network. Among them, the matching network is between the radio frequency power supply and the load of the inductively coupled plasma processing equipment, and is used to quickly adjust the corresponding parameters according to the change of the load impedance, so that the radio frequency power supply and the changing load are always in an impedance matching state. In inductively coupled plasma processing equipment, the load is the plasma in the reaction chamber. ...

AI Technical Summary

Problems solved by technology

However, when the source RF power system and the bias RF power system work in the same frequency band, this frequency band needs to be further subdivided into two smaller frequency bands, and the smaller working frequency band will lead to the matching impedance of the matching network The scope becomes smaller and may not meet the requirements of the actual process

[0005] In addition, when the process is long, the resistance part of the plasma impedance of the inductively coupled plasma processing equipment sometimes changes to a certain extent, but because the resistance part of the matching impedance of the fixed matching network is basically fixed throughout the process, Therefore, the fixed matching network for the automatic frequency modulation RF power supply cannot match the change of the resistance part of the plasma impedance well, so that the impedance matching between the bias RF power supply and the load cannot be adjusted well, and then there will be certain reflected power

For some processes that require a small value of bias power, such as the Bosch etching process, such reflected power will seriously affect the morphology of the via hole formed by etching

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