| On the base of reading many literatures and investigation, several different sputtering technologies were compared. Aimed at the specialties of Pulse Magnetron Sputtering (PMS) Technology and the choke point of Power Supply Technology, the requirements of the power supply parameters were proposed. The detail parameters are that the frequency is up to 300kHz, the negative voltage can be varied between 0V and -500V, the negative peak current can be reached 2 Amperes, the plus voltage can be varied between 0V and 100V, the plus peak current can be reached 1 Ampere, the negative Duty Ratio can be varied between 10% and 60%.In order to implement the requirements of the power supply parameters, the difficulties of the power supply which would be designed was analyzed: As a result of limitation of power electronics component, the component that the voltage value, current value and the frequency response meet the requirements is hardly found and expensive. Therefore, starting from topology, the whole solution for the power supply was proposed. The whole solution was that the power supply was composed of two independent DC/DC converters (used for regulating plus voltage and negative voltage, respectively), one chopper (used for forming plus pulse), and an invert frequency-doubled system (used for forming negative pulse). The core is the matching of invert frequency doubling system and the chopper. The problems of power electronics component was solved to some extent, thereby it made achieving power supply parameter index possible.According to the overall solution, a detailed discussion of choosing topology for main circuit, choice of power device, design of magnetic device, choice of snubber circuit, design of control circuit and design of driving circuit. After comparing the merit and the disadvantage of all kinds of topologies, as power supply parameters index required, the full-bridge topology and the forward topology was chosen used for negative and plus voltage regulation, respectively. The full-bridge topology was also chosen used for invert frequency doubling system, but the second windings current would be rectified by diode and Power MOSFET, which can block short circuit when the plus pulse was turned on. Owing to the circuit works in high frequency, the Power MOSFET was chosen as power switch. The influence of Miller effect to driving signal and the solution were described. The function of the snubber circuit and the choice of its parameters were also discussed.The problems and the detailed process of solving these problems in debugging the power supply were described on engineering experience. Real-time waveforms were tested by oscilloscope, and the influence of Miller Effect was verified. By means of detecting the load voltage and current waveform, the design indexes of power supply were achieved functionally, and the power supply can be used for do some experiment on magnetron sputtering in laboratory.Applied in Magnetron Sputtering experiment and compared with RF and DC Magnetron Sputtering, the A2K Power Supply'practicality and the advantage of PMS were verified. Therefore, this Power Supply can be used in Magnetron Sputtering experiment in laboratory. |
