In order to measure the deposition in the remote area behind the divertor of a tokamak due to plasma wall interactions (PWI) and get a better understanding of PWI process in this remote area in real time, the first quartz crystal microbalance (QCM) deposition diagnostic system for the HL-2A divertor was developed. After the preliminary test, it was found that the average sampling rate is about 13~14s-1 and its frequency resolution is 0.01Hz. The resonant frequency shift of the crystal is proportional to the mass change deposited in the surface of the crystal, which coincides with conclusion from the famous Sauerbrey equation. The average deposition rate is about 2.0ng?s-1, which means it is capable to measure nanogram quality. These results show that this QCM deposition system is reliable and effective.%为了检测HL-2A偏滤器靶板的背后沉积层的沉积情况和深入了解其等离子体与第一壁的相互作用过程,国内首次研制了用于托卡马克装置的偏滤器沉积测量系统,其中包括石英晶体、测量探头、频率测量以及控制系统等.经过初步检测,该沉积系统平均采样速率为13~14s-1;测量的石英晶体共振频率分辨率为0.01Hz;石英晶体共振频率的变化正比于沉积在石英晶体表面的质量的变化,这与Sauerbrey方程的线性关系吻合;实验室检测过程中该沉积系统的平均沉积率约为2.0ng?s-1,显示该沉积系统具有纳克级质量检测能力,表明了该偏滤器沉积系统的测量性能和有效性.
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