METHOD AND DEVICE FOR PLASMA ETCHING

PROBLEM TO BE SOLVED: To prevent the production of exfoliation and foreign matters by reducing the thickness of an unnecessary deposited film as much as possible by providing a mechanism which supplies electromagnetic waves having such a wavelength that is not absorbed by a member from the backside of the member, but by the unnecessary deposited film, at a constant intensity. SOLUTION: A substrate electrode 2 for placing a wafer 1 is provided with a power applying mechanism 4 connected to a power source 3 and a wafer temperature control mechanism 6 connected to a cooler (or heater) 5. An insulator layer 7 is formed around the mechanism 4 for preventing the leakage of electric power and the layer 7 is surrounded with a grounded earth plate 8. In addition, a lamp 9 which mainly emits light having a specific wavelength is buried in the layer 7. When the wafer is irradiated with the light emitted from the lamp 9, foreign matter producing spots can be removed and the cleaning frequency of the wafer 1 can be reduced remarkably. In addition, the number of persons required for the cleaning work of the wafer 1 can be reduced. Furthermore, the temperature of the wafer 1 can be raised easily, because the thin film has a small heat capacity is heated.