| 摘要 |
PURPOSE:To stabilize an analysis by providing a feedback system which detects the internal resistance of a glow discharge tube using a sample as a cathode and maintains the internal resistance of the glow discharge tube at approximately a constant level and maintaining a sputtering rate automatically at a constant value. CONSTITUTION:Gaseous argon is admitted through an inflow port 5 into the glow discharge tube G and is discharged from outflow ports 6 and 7. A flow rate control valve V is otherwise inserted into, for example, a gaseous argon supply pipe and the voltage drop generated across a resistor (r) connected in series to the discharge tube G is detected by a current detector D to control a valve driving device P via a comparator C, thereby opening and closing the valve V. The internal resistance of the discharge tube G increases and the tube current increases when the sputtering rate of the sample is low. The valve V is then opened to increase the gaseous argon pressure, by which the internal resistance is decreased and the sputtering rate is maintained constant. The stable analysis is thereby executed.
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