Abstract
This paper presents a novel multi-channel type RF source module with solid-state power amplifiers for plasma generators. The proposed module is consisted of a DC control part, RF source generation part, and power amplification part. A 2-stage power amplifier (PA) is combined with a gallium arsenide hetero bipolar transistor (GaAs HBT) as a drive PA and a gallium nitride high electron mobility transistor (GaN HEMT) as a main PA, respectively. By employing 8 channels, the proposed module secures better area coverage on the wafer during semiconductor processes such as chemical vapor deposition (CVD), etching and so on. Additionally, each channel can be maintained at a constant output power because they have a gain factor tunable by a variable gain amplifier (VGA). For that reason, it is possible to have uniform plasma density on the wafer. The operating sequence is controllable by an external DC control port. Moreover, copper–tungsten (CuW) heat spreaders were applied to prevent RF performance degradation from heat generated by the high power amplifier (HPA), and a water jacket was implemented at the bottom of the power amplification part for liquid cooling. Drawing upon the measurement results, the output power at each channel was over 43 dBm (20 W) and the drain efficiency was more than 50% at 2.4 GHz.
Highlights
The plasma generator is a device that supplies high-frequency output to the chamber to generate plasma in semiconductor process such as chemical vapor deposition (CVD), etching and so on [1,2].The conventional power amplifiers for the plasma generator mainly used a magnetron in the sub-GHz band [3,4,5]
The RF source generation part consists of a voltage controlled oscillator (VCO) to generate a 2.4 GHz RF signal and variable gain amplifier (VGA) to provide sufficient gain for the power amplification part, and the 8-way divider combined of 3 stages of
A novel 20 W 8-channel power amplifier module has been proposed for plasma generators
Summary
The plasma generator is a device that supplies high-frequency output to the chamber to generate plasma in semiconductor process such as chemical vapor deposition (CVD), etching and so on [1,2]. The GaN device has various characteristics such as high breakdown voltage, high electron mobility, high thermal conductivity, high efficiency characteristics and so on [7] It is very advantageous in terms of its small-form factor because it is possible to design it to be highly integrated with a semiconductor fabrication process in the high frequency band. In order to satisfy these criteria, the output of the power amplifier module termination should be constant and should be able to cover wide areas on wafers. The uniform plasma density, output poweroutput at eachpower channel has of 4 cm and can be tuned fromgain a variable gain(VGA). 2 describes what kind of components considered and how to design considered howIntoSection design the implemented proposed module.
Sign-in/Register to view highlights & summary Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
