| 摘要 |
PURPOSE:To uniform the physical characteristics of semiconductor wafer at the holding place and obtain the uniform etching characteristic by disposing the coolant path not only to the circumferencial side of lower electrode but also at the center side thereof. CONSTITUTION:A coolant path 23 is guided to the area near the circumference of electrode 21 along the circumference of semiconductor wafer holding place 221 from the coolant path entrance 23a provided at the center of lower electrode 21 and it is thereafter disposed along the external half circumference of the wafer holding positions 221-226. Moreover, the path 23 is folded to the inside along the circumference of the holding position 226 and then extended along the internal half circumference of the holding positions 226-221. Thereafter, it is disposed so that it is fed back to the coolant path exit 23b provided at the center of electrode 21. Since the path 23 is almost symmetrically disposed respectively to the holding places 221-226, the physical characteristics are uniformed within the range of respectively holding positions 221-226 and uniformly of etching rate can be improved. |
