Method and apparatus of diagnosing plasma in plasma space
AssigneesSamsung Electronics Co., Ltd., Industry-University Cooperation Foundation Hanyang University
InventorsKyung-Yub Jeon, Jeong-Yun Lee, Chin-Wook Chung
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Abstract
To diagnose plasma in a plasma space, a plurality of floating probes are installed at a plurality of points, respectively, in a plasma space. An electron density ratio at each of the points is calculated by measuring a first probe current of each of the floating probes, the probe current including a DC component. A point ion density and a point electron temperature at each of the points are calculated by measuring a second probe current of each of the floating probes before the electron density ratio is calculated, the second probe current excluding the DC component.
Claims19
An apparatus for diagnosing plasma in a plasma space, the apparatus comprising:
- a plurality of floating probes arranged at a plurality of points, respectively, in a plasma space, a height of the floating probes corresponding to a height of a wafer to be disposed in a wafer plasma process chamber defining the plasma space;
- a sensor circuit including a plurality of current sensing resistors;
- a DC select circuit including a plurality of DC switch circuits, each of the DC switch circuits being connected in series between each of the current sensing resistors and each of the floating probes;
- and
- a processor configured to calculate an electron density ratio at each of the points based on a first probe current of each of the floating probes, the first probe current including a DC component.
An apparatus for diagnosing plasma in a plasma space, the apparatus comprising:
- a plurality of floating probes arranged at a plurality of points, respectively, in a plasma space:
- a sensor plate on which the floating probes are uniformly arranged;
- a signal generator configured to generate an AC signal;
- a sensor circuit including a plurality of current sensing resistors connected to the signal generator;
- a DC select circuit including a plurality of DC switch circuits, each of the DC switch circuits being connected in series between each of the current sensing resistors and each of the floating probes, each of the DC switch circuits being configured to control an electrical connection between each of the current sensing resistors and each of the floating probes in response a control signal;
- and
- a processor unit configured to,
- generate the control signal to control the DC select circuit,
- measure a potential difference across each of the current sensing resistors,
- and calculate plasma parameters based on the measured potential differences.
An apparatus for diagnosing plasma in a plasma space, the apparatus comprising:
- a plurality of probes, each of the probes being configured to generate an associated probe current caused by the plasma, the probes being arranged in a two-dimensional plane at a substantially same height in the plasma space, the two-dimensional plane having a shape substantially identical to a shape of a wafer;
- a processor configured to generate a control signal;
- and
- a selection circuit configured to output one of first and second output currents based on the control signal, the first output current including a DC component of an associated probe current, the second output current excluding a DC component of an associated probe current.
Dependencies are inferred from the claim text.