RF power supply with digitally adjustable RF signal phase

Abstract

The invention discloses a radiofrequency power source with a digital adjustable radiofrequency signal phase. The radiofrequency power source comprises a radiofrequency signal generator, a radiofrequency power amplification circuit, a power supply line and a radiofrequency power detector. The radiofrequency signal generator comprises a phase adjustment circuit. The phase adjustment circuit is used for adjusting the phase of an external input radiofrequency signal. Since the phase adjustment circuit is embedded into the radiofrequency signal generator, the phase of a synchronously accessed radiofrequency signal can be accurately adjusted, the signal phase difference between the radiofrequency power source and a radiofrequency power source which provides the radiofrequency signal can be eliminated, crosstalk is avoided, and the process stability is improved; at the same time, the phase adjustment circuit employs digital control adjustment so that the precision is high.

Description

technical field [0001] The invention relates to a radio frequency power supply, in particular to a radio frequency power supply whose phase of a radio frequency signal can be digitally adjusted. Background technique [0002] RF power supply is a device used to generate radio frequency power signals, which is the core component of semiconductor process equipment. All equipment that generates plasma for material processing requires RF power supply to provide energy. Process manufacturing equipment for integrated circuits, solar cells and LEDs (Light Emitting Diodes, light emitting diodes), such as etching machines, PVD (Physical Vapor Deposition, physical vapor deposition), PECVD (Plasma Enhanced Chemical Vapor Deposition, plasma enhanced chemical vapor deposition), ALD (Atomic Layer Deposition, atomic Layer deposition) and other equipment are equipped with RF power supplies of different power specifications. [0003] The RF power supply is generally composed of an RF signal ...

AI Technical Summary

Problems solved by technology

Usually, the phase synchronization between two RF power supplies in semiconductor process equipment is to use a coaxial cable to connect the RF signal synchronization output end of one RF power supply with the RF signal synchronization input end of another RF power supply, thereby The two RF power supplies use the same RF signal, and it is expected to eliminate the phase difference and avoid crosstalk; however, even if the two RF power supplies are in the same cabinet (or machine), the length of the coaxial cable connecting the two RF power supplies is also limited. at least tens of centimeters

Since the radio frequency frequency commonly used in semiconductor process equipment is 13.56MHz, that is to say, the wavelength in vacuum is only 22.12 meters, while the wavelength in coaxial cables is shorter, generally only about 16 meters, divided into 360 degrees, that is, 4.4 cm The difference is only 1 degree, so the coaxial cable of tens of centimeters will also cause a large phase difference. In some cases, this phase difference is likely to cause plasma oscillation, the glow is unstable, and the process cannot be carried out normally. eventually lead to processing failure

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