Impedance matching system and impedance matching method

Abstract

The invention discloses an impedance matching system and an impedance matching method. The system comprises a sweep frequency power supply, a matching device, a sensor, and a controller respectively connected with the sweep frequency power supply, the sensor and the matching device. The controller judges whether the output impedance of the sweep frequency power supply matches the impedance of a reaction chamber. When the output impedance of the sweep frequency power supply mismatches the impedance of the reaction chamber, the controller judges whether the input impedance of the matching device is within the range of impedance which can be matched by the sweep frequency power supply. The controller keeps the impedance of the matching device unchanged and adjusts the output frequency of the sweep frequency power supply to enable the output impedance of the sweep frequency power supply to match the impedance of the reaction chamber if the input impedance of the matching device is within the range of impedance which can be matched by the sweep frequency power supply, or the controller keeps the output frequency of the sweep frequency power supply unchanged and adjusts the impedance of the matching device to enable the input impedance of the matching device to be within the range of impedance which can be matched by the sweep frequency power supply, and then adjusts the output frequency of the sweep frequency power supply to enable the output impedance of the sweep frequency power supply to match the impedance of the reaction chamber.

Description

technical field [0001] The invention relates to the technical field of semiconductors, in particular to an impedance matching system and an impedance matching method. Background technique [0002] Plasma technology is widely used in the fields of semiconductor, flat panel display, solar energy and industry. How to efficiently and rapidly excite plasma has become the key to plasma technology. RF plasma generation as figure 1 As shown, the RF power supply 1' transmits the RF energy to the reaction chamber 3' through the matching device 2', and the RF energy in the reaction chamber 3' excites gases with a certain pressure, such as helium, argon, etc., into plasma Perform etching, cleaning, coating, etc. However, since the output impedance of the RF power supply 1' is a certain resistance value (generally 50Ω), and the impedance of the reaction chamber 3' is not equal to the output impedance of the RF power supply 1', all the RF power cannot be transmitted to the reaction cha...

AI Technical Summary

Problems solved by technology

[0003] The existing matcher 2' uses mechanical adjustment to achieve matching, which has the disadvantages of slow matching speed and insufficient precision

There are also some frequency sweeping power supplies to achieve matching by adjusting the frequency, but because the variable frequency range of the sweeping frequency source is relatively narrow, its process window is relatively narrow

Moreover, it cannot complete the matching independently and needs to cooperate with the fixed matcher 2' to achieve matching. In different process windows, the fixed matcher 2' needs to be replaced, so it is only suitable for fixed processes

It is more troublesome to implement under the multi-process window

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