Double-layer megawave cleaning system

Abstract

The invention relates to a double-layer megawave cleaning system which comprises a base, an ultrasonic signal generating device, a bath and a cleaning tank used for wafer cleaning, the ultrasonic signal generating device is installed on the base, the base is a movable base, and the base moves to change the direction of sound waves emitted by the ultrasonic signal generating device relative to the cleaning tank; the bath is mounted at the upper end of the ultrasonic signal generating device, and a sound wave conduction medium is contained in the bath; the cleaning tank is installed above the bath tank, the bottom of the cleaning tank is immersed in the sound wave conduction medium in the bath tank, and cleaning liquid is contained in the cleaning tank. The sound wave direction of the ultrasonic signal generating device is changed through movement of the base, the projection area of the wafer in the sound wave direction is changed, then the cleaning effect and efficiency are improved, meanwhile, pressure difference is generated at the bottom of the cleaning tank through change of the sound wave direction, bubbles gathered at the bottom of the cleaning tank are eliminated, energy loss of ultrasonic waves is reduced, and the cleaning effect is improved. The cleaning effect is improved.

Description

technical field [0001] The invention relates to the field of semiconductor process equipment, in particular to a double-layer megawave cleaning system and a cleaning method. Background technique [0002] Traditional ultrasonic cleaning equipment has been used in the cleaning of semiconductor crystal wafers for a long time. As the process line width becomes smaller and smaller, the cleaning requirements are getting higher and higher, and the frequency of ultrasonic waves is also increasing, from kilohertz to megahertz. . However, as the frequency of the sound wave increases, the directional characteristics and energy attenuation of the sound wave become more obvious. Most of the traditional cleaning methods place the wafer vertically above the ultrasonic signal generator. The projection area of ​​the wafer to the ultrasonic wave is small, and the cleaning effect of the middle and top of the wafer is weaker than that of the bottom. [0003] Existing cleaning equipment genera...

AI Technical Summary

Problems solved by technology

[0006] Under the condition of the same power, the existing technology increases the utilization rate of ultrasonic waves, but the contact area between the ultrasonic wave transmission direction and the wafer surface does not change, and the projected area of ​​the wafer within the ultrasonic wave transmission range does not change.

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