Analysis And Research Of Solid State RF Generator System

With the improvement of production process automation, high-power RF power generator controlled by computer and used in microelectronics devices such as etching machine, sputtering equipment and PECVD should be provided with small volume, stable frequency, power tuning automation, impedance automatic matching, real-time display RF power, real-time display equipment temperature, overheating protection system, automatic detection working state, fault alarm function, telemetry control through communication interface, production parameters stored and controlled by computer and precision closed-loop control. These are the development trend of RF generator in the future.However, most power amplifiers used in domestic RF generator are electron tubes. The RF generator using electron tube has large volume, low conversion efficiency, short useful life. Solid-state RF generator will replace RF generator using electron tube because of its high efficiency, small volume and long useful life.The most advanced Class-E power amplifier is used in this dissertation. The principle of Class-E and matching network are analyzed and parameters of matching network are derived. The whole RF system is simulated through MULTISIM of NI Company and the S parameters are simulated by ADS. The driver stage circuit board and power amplifier stage circuit are tested and debugged respectively. RF power of stability and power output are influenced greatly by the heat dissipation of drive stage circuit board and power amplifier stage circuit. Theoretical derivation and simulation parameters are different from the parameters of the actual circuit. The reason of difference is that theoretical derivation and simulation parameters are obtained in ideal state. For example, RF power amplifier was assumed to work on the switch mode (Class-E). The switch is no loss. However, in reality, power amplifier cannot strictly work in Class-E, because of itself encapsulation and parasitic capacitance inductance. Switching loss is inevitable. Most simulation model cannot simulate the parameters of actual circuit completely; especially the distributed parameters exist because of high frequency. The great differences of theoretical derivation and simulation parameters and parameters of actual circuit exist. Although the great differences exist, The theoretical derivation and simulation are necessary because of the guidance to make actual circuit.The ultimate test results indicate that this solid state RF generator compared to the solid RF generator of AE has the superior performance such as frequency stability, power stability, and biggest reflection power. This solid state RF generator reach the final goal that we will develop solid-state RF generator with independent intellectual property rights. Its main parameters reach or pass the technical level of the same products abroad and finally we put it into industrialization and commercialization.