| 摘要 |
PROBLEM TO BE SOLVED: To provide a means for measuring the potential difference of plasma and current of plasma, generated on a wafer, which are important quantities in a semiconductor-surface processing apparatus using plasma, without modifying apparatus. SOLUTION: The light intensity of a light emitting diode 201 positioned on a wafer 105 was measured, thereby, the potential difference between terminals of the light emitting elements and the plasma current passing into the light emitting elements are obtained. Since the light intensity can be measured in non-contact by using a camera, the inlet terminals for conductor like a prior probe method become unnecessary. Additionally, an exchange of wafer can be carried out the same as etching because it is not necessary to attach a conductor to the wafer. |
