Impedance matcher, semiconductor equipment and impedance matching method

Abstract

The invention discloses an impedance matcher, semiconductor equipment and an impedance matching method. The impedance matcher comprises an impedance sensor, an impedance matching network, a computing control unit and an execution unit. The impedance sensor comprises a sampling module, a filter module and a signal processing module. The sampling module is used for detecting an input end of the impedance matching network and obtains impedance detecting signals. The filter module is used for filtering out interference signals with specific frequency in the impedance detecting signals. The signal processing module is used for carrying out computing processing on the impedance detecting signals after filter processing to generate input impedance relevant signals of the impedance matching network. The computing control unit is used for carrying out computing processing on the input impedance relevant signals to generate impedance adjusting data. The execution unit is used for adjusting the impedance matching network according to the impedance adjusting data so that input impedance of the adjusted impedance matching network and output impedance of a radio-frequency power supply are matched in a conjugate mode. The impedance matcher can accurately achieve impedance matching.

Description

technical field [0001] The invention relates to the technical field of microelectronics, in particular to an impedance matching device, a semiconductor device and an impedance matching method. Background technique [0002] Plasma is widely used in the production process of semiconductor devices. In plasma equipment, an RF power supply provides RF signal energy to a reaction chamber to generate plasma. Plasma contains a large number of active particles such as electrons, ions, excited atoms, molecules, and free radicals. These active particles interact with the wafer placed in the reaction chamber and exposed to the plasma environment, causing various occurrences on the wafer surface. Physical and chemical reactions, so that the surface properties of the wafer change, and the etching or other processes of the wafer are completed. [0003] In order to match the output impedance of the RF power supply with the impedance of the reaction chamber, an impedance matcher (Impedance...

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Problems solved by technology

[0005] However, the plasma equipment adopts the structure of dual radio frequency power supply, and the two radio frequency power supplies will produce a dual frequency interference effect, which makes it impossible for the impedance sensor to accurately measure the input impedance of the impedance matching device. For example, high frequency interference signals will interfere The impedance sensor in the second impedance matching device makes the impedance sensor unable to accurately measure the input impedance related signal of the second impedance matching device; the low-frequency interference signal will interfere with the impedance sensor in the first impedance matching device, so that the impedance sensor cannot Accurately measure the input impedance related signal of the first impedance matcher, which reduces the measurement accuracy of the impedance sensor, so that the impedance matcher cannot achieve impedance matching

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