Plasma generation method and device, and semiconductor processing equipment

Abstract

The invention provides a plasma generation method and device, and semiconductor processing equipment. The plasma generation method comprises the following steps that an upper radio frequency source outputs a main pulse signal so as to motivate a technology gas in a reaction chamber to form a plasma; and in the closing phase of the main pulse signal, the upper radio frequency source outputs one ormore auxiliary pulse signals, and the auxiliary pulse signals can maintain the plasma in the reaction chamber to be in a starting state during the closing phase of the main pulse signal. By using theplasma generation method, the auxiliary pulse signals are used to maintain the plasma in the reaction chamber to be in the starting state during the closing phase of the main pulse signal, and the plasma in the reaction chamber can be prevented from being quenched during the closing phase of the main pulse signal due to insufficient loaded main pulse power so that the stable generation of the plasma in the reaction chamber and the enlargement of a technology window are realized, and a plasma technology can be performed stably.

Description

technical field [0001] The invention relates to the technical field of magnetron sputtering, in particular to a plasma generation method and device and semiconductor processing equipment. Background technique [0002] In semiconductor equipment, the plasma equipment used for silicon etching process usually adopts the principle of inductively coupled plasma (ICP), and the radio frequency energy is provided by the radio frequency power supply to ionize the special gas (such as argon Ar, helium, etc.) in the high vacuum state in the chamber. Gas He, Nitrogen N 2 , hydrogen H 2 etc.), generate a plasma containing a large number of active particles such as electrons, ions, excited atoms, molecules and free radicals, and complex interactions between these active particles and the wafer placed in the cavity and exposed to the plasma environment The interaction causes various physical and chemical reactions to occur on the surface of the wafer material, thereby changing the surfac...

AI Technical Summary

Problems solved by technology

[0007] In prior art 1, when the upper electrode system and the lower electrode system are simultaneously loaded with a pulse signal and started, due to the short power loading time in the pulse mode, it is difficult for the plasma to achieve ignition, so the hardware window of the equipment is small

Especially when the duty cycle is small, due to the short power loading time, it is easy to cause the plasma to fail to ignite or to be unable to maintain and then extinguish after igniting.

like Figure 4 As shown, when the pulse synchronization signal has a low duty cycle, matching is difficult, and multiple pulse cycles are required to achieve ignition and matching. Figure 4 In the middle, the ignition is realized at the time point Ti, and the stable matching impedance Z and the stable plasma density ni are achieved at this time, but it will soon be extinguished due to insufficient energy to maintain the ignition (for example, the extinction at the time point Tj), and it is impossible to maintain the temperature of the plasma

In prior art 1, the initiation of chamber plasma in pulse mode is unstable, resulting in poor process repeatability

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