High selective ratio and high and uniform plasma processing method and system

Abstract

A plasma processing method and a plasma processing system provide advantages of a high degree of selectivity, a large area processing capability and an enhanced precision level. A plasma processing method according to the invention is so designed that a pulse modulation power is supplied alternately to the plasma generating power supply and the substrate bias power supply by referring to the time taken by gas to diffuse from the center of electric discharge to the substrate. In a plasma processing system according to the invention, the plasma generating power supply and the substrate bias power supply are provided with modulation means for supplying a pulse modulation power alternately to the plasma generating section and the substrate electrode by referring to the time taken by gas to diffuse from the center of electric discharge to the substrate.

1 . A system for uniformly plasma-processing a substrate on a substrate electrode at a high selectivity ratio and over a large area by applying a spatially even or uneven and temporally constant or modulated magnetic field to the plasma generating section of a vacuum container, generating a magnetic neutral line discharge plasma by means of a radio frequency antenna circuit and a plasma generating power supply connected to the radio frequency antenna circuit and supplying modulated substrate bias power to the substrate electrode in the vacuum container from a substrate bias power supply, wherein 
 the plasma generating power supply and the substrate bias power supply are provided with modulation means for supplying a pulse modulation power alternately to the plasma generating section and the substrate electrode by referring to the time taken by gas to diffuse from the center of the generated plasma to the substrate,    the plasma generating radio frequency antenna circuit comprising parallel coils for independently regulating the inter-gap distance in the azimuth direction.    
     
     
         2 . A system according to  claim 1 , wherein 
 the plasma processing comprises plasma etching using an etchant, and the modulation means provided at the plasma generating power supply and the substrate bias power supply are so arranged as to carry out the pulse modulation according to both the power supplied to the radio frequency antenna circuit and the substrate bias power supplied to the substrate electrode by referring to the etchant diffusion time or the etchant service life.    
     
     
         3 . A system according to  claim 1 , wherein the parallel coils are arranged in such a way they provide positional coordination of the magnetic fields adapted to generate the magnetic neutral line discharge plasma in the plasma generating section of the vacuum container.