| 摘要 |
<p>An asymmetric Langmuir probe is placed in the ionized gas plasma between the target and the collector. Its output is fed to an amplifier swept by a sawtooth waveform generator through the probe characteristic curve. After double differentiation, the amplified probe signal is fed to a bistable gate reset by the differentiated sawtooth. The bistable output is fed to an averaging amplitude detector whose second input is the sawtooth. A dc voltage measuring instrument is connected between the output of that amplitude detector and the collector. Automatic compensation for phase errors of the RF voltage in the shadow zones of the chamber increases accuracy of measurement.</p> |
