| abstract |
PURPOSE: To uniformize the distribution of the electromagnetic field intensity of a microwave in a plasma generating chamber and to contrive the improvement of the uniformity of a plasma treatment by a method wherein part of the microwave forming an uneven part of a plasma density in the plasma generating chamber is removed. n CONSTITUTION: An absorber 13 provided with a quartz ring 14, on which a tin oxide film 15 is formed, is arranged on the upper part of a discharge tube 2. Part of a microwave 11 propagated in a waveguide 3, part of plasma produced in the tube 2 or part of the microwave 11 reflected by a sample stand 7 are absorbed in the absorber 13. When the microwave, which is absorbed in the absorber 13, enters or reenters in the region of the plasma 12, it is a microwave which generates a high plasma density and the remaining microwave enters or reenters the region of the plasma 12 and contributes to the generation of the plasma. Thereby, a plasma treatment can be uniformized. A reflective member, a resistive film or the like may be used in addition to the absorber 13. n COPYRIGHT: (C)1991,JPO&Japio |