Other

Seiichi Takasuga

Hideo Sugai

Naoki Toyoda

A plasma density information measuring method capable of easily measuring the plasma density information over the long term, a probe for measuring the plasma density information, and a plasma density information measuring apparatus are disclosed. A measuring probe is set such that a tip end of a glass tube of the measuring probe is brought into contact with plasma PM to be measured. High-frequency power sent through a coaxial cable is supplied to the plasma PM from a loop antenna through a wall of the tube, and reflection power of the high-frequency power is received by the loop antenna to obtain a counter frequency variation of reflection coefficient of the high-frequency power. In the obtained reflection coefficient, a portion thereof in which the reflection coefficient is largely reduced is a peak at which strong absorption of high-frequency power is caused due to the plasma density. The plasma density can be obtained from the plasma absorption frequency.

Plasma density information measuring method, probe used for measuring plasma density information, and plasma density information measuring apparatus

A plasma generating apparatus and a method for controlling plasma-generating high frequency power capable of appropriately and easily controlling plasma density over the long term are disclosed. Measuring high frequency power is supplied to plasma through a dielectric tube. Apart from a supply system of plasma-generating high frequency power, there is provided a plasma density information obtaining section having long lifetime no hot filament. The plasma density information obtaining section obtains the plasma density information by measuring a physical amount related to reflection or absorption of the high frequency power. An actually measured plasma density monitored by the plasma density information obtaining section from moment to moment and a target plasma density held in a plasma density setting section are compared. Based on this compared result, an impedance matching device is changed, and an impedance matching state between the electric source side and the plasma side, thereby appropriately controlling the generating high frequency power output from the high frequency electric source.

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Takarazuka, Japan

Seiichi Takasuga